Abstracts for the Xth World Congress of Psychiatric

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Abstracts for the Xth World Congress of Psychiatric Genetics The Palais des Congre´s Brussels, Belgium October 9 –13, 2002 Sponsored by the International Society of Psychiatric Genetics

Program Committee Chairpersons: Christine Van Broeckhoven, Ph.D., D.Sc., and Julien Mendlewicz, M.D., Ph.D.

Abstracts Organized and Edited by: Gise`le Smeyers & Christine Van Broeckhoven, Julien Mendlewicz, Markus No¨then, Stephan Claes, Jurgen Del-Favero, and Daniel Souery, Members of the Local Organizing Committee

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Plenary Lectures L1 PSYCHIATRIC GENETICS IN ITS HISTORICAL CONTEXT Gottesman I Departments of Psychiatry and Psychology, University of Minnesota, Minneapolis, Minnesota We cannot escape the history of our field and are constantly guided today by the accumulation of facts with either positive or negative valences from our past. But when did the clock start—with the domestication of animals, with Galton’s musings and amoral passion for data collection about individual differences in behavior, or with the initially objective scientizing of Mendelism applied to schizophrenia but ending with a Nazi-tainted albatross around the neck of psychiatric genetics. In regard to the long quest for the distal and genetic (partial) causes of mental diseases, the conclusion that both genetic and environmental factors, none yet known in detail, provide the distal causes of mental disorders—that statement is too general to be of use to making further progress. What is needed is a confrontational approach based on evidence collected from competing ‘schools of thought’, and then reconciliation before some kind of omniscient and impartial Science Court. With each new tool that was developed, from pedigree-ing, to correlation, to path analysis, to segregation analysis, to electrophoresis, to liability-threshold modeling, to linkage and association, to SNPs, and to gene expression via microchip arrays, there has been a strong tendency to put our eggs into one near-sighted basket. Erik Stromgren, one of the Danish elders, cautioned us to avoid the ‘‘tyranny’’ of technology. Research into the etiologies of major mental diseases was facilitated by adopting the approach used for complex adaptive systems as pursued by those who study coronary artery disease and diabetes. But why did it take so long embrace the strategies of complex diseases, including epigenetic perspectives, and to abandon the fixation on single major locus hypotheses? Still, weights to indicate the relative importance of putative risk factors require an awareness of odds ratios and effect sizes. The challenge to our field is to join into cross-disciplinary collaborations as well as to adapt to blind alleys more rapidly with novel or borrowed strategies, thus informing therapies. L2 AUTONOMY AND GENETICS OF BEHAVIOR Mordini E Centre for Science, Society and Citizenship, Rome, Italy The advent of recombinant DNA technology has resulted in a number of new discoveries. More and more we can interfere with or diagnose diseases, detect presymptomatically genes for monogenic disorders, uncover (early in life) genetic predisposition to common disorders (including psychiatric disorders), anticipate normal phenotypic traits, and, in the near

future, even foresee behavioral traits, such as novelty seeking behaviors, antisocial behaviors, and sexual orientation. Character is the destiny—claimed Heraclitus, the ancient Greek philosopher—and the Nobel Prize, J. Watson stated: ‘‘We used to think our fate was in our stars. Now we know, in large measure, our fate is in our genes.’’ Similarly, another distinguished scholar, the French geneticist J. F. Mattei, expressed the same concept. ‘‘We are the fortune-tellers of modern times. Southern blots now replace the crystal ball.’’ Most people, scholars included, agree that the new genetics offer possibilities of great importance, even if some of the future scenarios may create anxiety and concern. Perhaps, the main reason for concern involves the predictive nature of genetics. To find out regularities and, consequently, to foresee future events, is one of the major tasks we have assigned science in Western culture, and also human biology searches for causal explanations for what we are and do. Humans have always been fascinated, although also frightened, by the idea of being able to foresee their future, and modern genetics promises to unveil some aspects of their ‘‘biologic future.’’ The ‘‘emotional value’’ of genetics is therefore fully comprehensible, and the contradictory set of fears and hopes that scientific research in this field has provoked. Determinism in the physical sciences does not pose major problems to the public, since people are used to considering ‘‘nature’’ as ruled by universal and necessary laws (of course philosophers and scientists may contest that this idea is unproblematic). Determinism creates a lot of problems when applied to humans because it challenges the concept of free will and moral autonomy. L3 TRACKING GENES OF NEUROPSYCHIATRIC DISEASES USING ISOLATED POPULATION Peltonen L Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland and Department of Human Genetics, UCLA, Los Angeles, California The high number of catalogued sequence variants facilitates genome-wide studies of genetic loci behind neuropsychiatric diseases. However, multiple uncertainties must be solved before the best possible strategy for the gene hunt can be designed. Which phenotypes to include, which study population (isolated or outbred) to choose, which type of markers (STRs or SNPs) to be employed, and how to select the variants to be genotyped? Rapidly increasing information of the structural or functional variability within the genome (long range rearrangements, patterns of gene expression) significantly affects the interpretation of data. LD and haplotype sharing have been very useful for mapping and positional cloning of rare disease genes in population isolates like Finland. The advantage of isolates for common disease genes has been challenged, and only few samples exist for diseaserelated haplotype signatures or associations in common

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disease alleles in any population. I will describe the features of the Finnish population and our efforts to search for disease loci for rare and common neuropsychiatric phenotypes to exemplify strategies to identify disease genes using Finnish data sets. LD intervals in common alleles and the prevalence of disease mutations are strikingly different in different regional subpopulations, emphasizing the importance of detailed information of the population history. Accurate genealogical information facilitating the construction of large pedigrees in regional subisolates has proven highly beneficial for our studies. Typically the initial genotyping has been carried out with maximally informative multiallelic markers to identify shared haplotypes among affected family members. Shared regions have been targets for dense SNP mapping and statistical analyses combining the power of linkage and association. This strategy has exposed well-defined critical chromosomal regions in common diseases like schizophrenia and multiple sclerosis. Even potential predisposing DNA-variants have been identified in phenotypes like lactose intolerance and familial combined hyperlipidemia. The general significance of these variants remains to be verified in large epidemiological cohorts and functional studies. L4 ANIMAL MODELS FOR PSYCHIATRIC DISEASES: A GENETIC ANALYSIS OF OPIOID AND TACHYKININ PEPTIDE FUNCTIONS Bilkei-Gorzo A, Ra`cz I, Miche K, Zimmer A, Zimmer A Klinik und Poliklinik fu¨r Psychiatrie und Psychotherapie, Molekulare Neurobiologie, Bonn, Germany Understanding the neurobiology of complex behaviors remains one of the most important and most difficult scientific challenges. Our laboratory has taken an integrative approach to study the neuronal mechanisms involved in nociception, drug addiction and emotional behaviors, which is based upon genetically modified mouse strains. One topic of special interest is the functional analysis of modulatory opioid and tachykinin neuropeptides. The neuropeptides play important, and often antagonistic roles, in various neuronal circuits. The analyses of mutant mouse strains have provided novel insights into the functional importance of these molecules, and suggested a possible role in the pathomechanisms and possibly the ethiology of neuropsychiatric disorders. L5 THE IMPACT OF GENOMICS ON ANTIDEPRESSANT DRUG DISCOVERY—FROM SERENDIPITY TO HYPOTHESIS AND BACK Holsboer F Max Planck Institute of Psychiatry, Munich, Germany The currently available antidepressants, anxiolytics and antipsychotics were serendipitously discovered in the fiftees and since then we are awaiting a major innovative breakthrough leading to better drugs. The uncertainty how our knowledge about pharmacological drug actions relates to their clinical

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effects is one reason for the lacking progress. The systematic identification and functional analysis of the human genome promises to build a new fundament for future drug discovery. Moreover, genotyping can ultimately cut down interindividual variability in drug response and risk for adverse drug reactions. To achieve the goal of individualized pharmacotherapy, refined phenotyping, beyond complementary traditional psychopathology ratings is indispensable. The Munich Antidepressant Response Signature (MARS)project can serve as an example how the opportunities provided by biotechnology can be transcended into innovative pharmacopsychiatry. In the MARS-project, patients with a depressive syndrome are functionally phenotyped according to neuropsychologcial neuroimaging and neuroendocrine measures. Also their clinical course under defined pharmacological regimen is monitored. A SNP analysis will be performed and polymorphisms will be tested for association with drug-specific outcomes. The genes to be analyzed are selected from cDNA-array experiments, where mouse brains were investigated according to antidepressant-elicited changes in gene activity. Hereby, several genes are already identified that code for potential drug targets. Along the same line we compared gene-activity in mouse brains where the corticotropin releasing hormone receptor type 1 (CRHR1) gene was deleted with those who had received a CRHR1antagonist and identified a number of commonly regulated genes. The extent of drug-induced changes, however, was determined by the genotype of the individual mice indicating a strong genotype-dependent drug response. These findings are just the beginning of a new research era ultimately contributing to individualized psychopharmacology. L6 LONGITUDINAL TWIN-FAMILY STUDY OF PERSONALITY AND PSYCHOPATHOLOGY IN THE NETHERLANDS Boomsma DI Dept. of Biological Psychology, Vrije Universiteit, Amsterdam, The Netherlands Between 1991 and 2000 a large sample of Dutch families participated in a longitudinal study of personality, psychopathology, lifestyle and health. Adolescent and young adult twins, their parents, siblings and in the 2000 survey also their partners participated between one and five times. A total of 10, 357 offspring, over 4000 parents and over 700 spouses of twins took part in the study. This presentation will review approaches for the analysis of such multivariate, longitudinal data collected in parents and offspring, twins and siblings and twins and spouses and summarize the main findings regarding the causes of variation in personality (several dimensions of sensation seeking, neuroticism, extraversion and type-A behavior) and psychopathology (depression, anxiety, somatic anxiety, aggression and attention problems). For nearly all traits we find a significant contribution of genetic influences

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to individual differences, little or no influence of a common environment shared by family members and a low correlation between spouses. The covariance/comorbidity of traits is explained for the largest part by a common set of genes, as is the stability of individual differences over time. L7 GENETICS OF PERSONALITY DISORDERS Torgersen S Department of Psychology, Oslo University, Norway A number of twin and adoption studies have demonstrated that the variation in most, if not all, personality dimensions and traits are partly due to genetic variation. The same is also true for variation in quality of life, so called ego-development, mental adjustment and mental disorders. Less is known about the role of genetic factors in the development of personality disorders. A number of studies have suggested that antisocial and criminal behavior are influenced by genes. A few studies have demonstrated the same for schizotypal personality disorder. Recently, a study of deviant personality features in the common population and a study of personality disorders among psychiatric patients have disclosed that all or almost all personality disorders are genetically influenced. The novel studies will be presented.

Special Plenary Lectures SL1 META-ANALYSIS OF GENOME SEARCHES: METHODS Lewis CM,1 Wise LH,1 and Levinson DF2 1 Division of Medical and Molecular Genetics, Guy’s, King’s & St Thomas’ School of Medicine, London, UK 2 Department of Psychiatry, University of Pennsylvania, Philadelphia Genome searches are widely used to localize susceptibility genes for complex diseases, but in general these studies have been disappointing, with low power to detect linkage and little replication of linked regions across studies. The Genome Search Meta-Analysis (GSMA) method was developed to allow pooling of results across genome scans. It uses standard output (scores or p-values) from linkage studies, without requiring investigators to re-analyze data. The GSMA can be applied to all genome-wide linkage studies regardless of the study design and analysis method used. GSMA divides the genome into 120 bins of approximately 30 cM length. For each scan, the most significant linkage score in each bin is selected, and the bins ranked (with the most significant bin given rank 120). For each bin, ranks are summed across studies. Under the null hypothesis of no susceptibility gene within a bin, ranks from each study will be randomly assigned from 1 to 120, and the null distribution of summed ranks can be obtained. A high-summed ranks indicates clustering of more positive linkage scores within that bin. Point-wise significance of each bin is obtained by

calculating the probability that a bin has a summed rank greater than its observed value. A genome wide analysis can also be performed: we simulate ranks for all studies, and note the distribution of the order statistics (120th summed rank, 119th summed rank, etc.) to compare this to observed summed ranks. A departure of observed values from those expected for high order statistics indicates the presence of susceptibility loci, and gives a genome-wide evaluation of significance. Studies can also be analyzed using a weighting function, based on the number of affecteds or pedigrees in a study. Study ranks are multiplied by the study weights prior to summing across studies, and significance assessed by simulations of weighted ranks. Results will be presented from a simulation study, based on the schizophrenia studies, We determined the power of the GSMA to detect linkage under heterogeneity, assuming 1–10 susceptibility genes, each having a sibling recurrence risk of 1.2–1.4. SL2 META-ANALYSIS OF GENOME SCANS FOR SCHIZOPHRENIA Levinson DF,1 Lewis CM,2 Wise LH,2 and 16 contributing groups 1 Department of Psychiatry, University of Pennsylvania, Philadelphia 2 Division of Medical and Molecular Genetics, Guy’s, King’s & St Thomas’ School of Medicine, London, UK Schizophrenia is a common and disabling disorder with a heritability of 0.70–0.85 and a tenfold increase in risk to siblings of probands, yet reports of significant evidence for genetic linkage have not been consistently replicated. One explanation would be that small genome scans often overestimate the genetic effects associated with the most positive regions. The true population-wide effects of schizophrenia susceptibility loci may be small and reliably detectable only in much larger samples. To assess evidence for linkage across studies, Genome Scan Meta-Analysis was applied to data from 20 genome scans carried out by 16 research groups, using a narrow diagnostic model (schizophrenia þ schizoaffective disorder), except where the only analysis performed had included small numbers of cases with other diagnoses. Simulations demonstrated a probability of less than 0.5% of observing eight summed ranks as large as were observed here, or 4.1% for the nine largest sums, on chromosomes 2p-q (101.6–154.5 cM on the Marshfield map, with the largest sum in the proximal region), 3p (32.4–63.1 cM), 11q (99.0– 123.0 cM), 5q (131.5–164.2 cM), 20p (21.2–47.5 cM), 8p (27.4–55.0 cM), 6p (0–32.6 cM) and 22q (0–33.8 cM). These results were significant regardless of whether scans were weighted equally or were weighted according to sample size (here, by the square root of the number of affected cases, but other weighting schemes performed similarly). There may be greater consistency of linkage results across studies than has been previously recognized. The results suggest that some or

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all of these regions contain schizophrenia susceptibility loci, although it is likely that this method would detect all such loci. SL3 META-ANALYSIS OF GENOME SCANS FOR BIPOLAR AFFECTIVE DISORDER Segurado R,1 Detera-Wadleigh SD,2 Gill M,1,3 Levinson DF,4 Lewis CL,5 and 18 contributing groups 1 Department of Genetics, Trinity College Dublin, Ireland 2 NIMH/NIH, Bethesda, Maryland 3Department of Psychiatry, Trinity Centre for Health Sciences, St. James’ Hospital, Dublin, Ireland 4 Department of Psychiatry, University of Pennsylvania, Philadelphia 5 Division of Medical and Molecular Genetics, Guy’s, King’s & St Thomas’ School of Medicine, London, UK Linkage studies in bipolar affective disorder have been notable for the lack of loci demonstrating consistent evidence for linkage. The persistence of discrepancies in the locations of maximum lod scores suggests extensive genetic heterogeneity, or lack of power to discover underlying loci of very small effect. Meta-analysis thus provides an avenue for increasing power, and determining the level of consistency across genome scans. The rank-based Genome Scan Meta-Analysis (GSMA) method was applied to completed genome scans in bipolar disorder, comprising all 22 known studies both published and unpublished. The analysis has been complicated by the diversity of phenotypic models used across studies and the large variation in sample sizes. The analysis has been completed for a narrow diagnostic model (bipolar I þ schizoaffective-bipolar disorder) for the 10 genome scans which were analyzed under this model. The 10 scans included 959 affected individuals from approximately 350 pedigrees. A nominal (by-bin) 5% level of significance was observed for six bins of 30 cM width under both the unweighted scheme, and when weighted by the number of affected individuals minus the number of pedigrees. These bins are located on chromosomes 1p (83–114 cM, Marshfield map), 9p (27–54 cM), 18q (63–97 cM), 17p-q (25–64 cM), 10q (62–91 cM), and 6q (99–131 cM). We note that most of these are not regions associated with the most significant p-values reported by individual studies. Analyses under broader phenotype models are underway and will be reported at the meeting.

Symposium 1: Post Genome Technology S1 GENOMICS: SCIENCE AND SOCIETY Van Ommen GJB Dept. of Human Genetics, Leiden University Medical Center, The Netherlands The Human Genome Project, the mapping of our 30.000– 50.000 genes and the sequencing of all of our DNA, will have

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major impact on biomedical research and the whole of therapeutic and preventive health care. The tracing of genetic diseases to their molecular causes is rapidly expanding diagnostic and preventive options. The increased insights into molecular pathways, gained from high throughput ‘functional genomics’, using DNA? and protein? chip approaches and specially? designed animal model systems, will open great perspective for pharmacological and genetic therapies. Powerful bioinformatics and biostatistics will further improve our pattern recognition and accelerate progress. A rapidly expanding area of high expectations is that of ‘pharmacogenomics’: The design of more effective drugs with lower toxicity, through tailoring of drug treatment to individual, genetically determined differences in drug metabolism. Not only will this reduce the cost of health care through decrease of adverse drug reactions, but a better stratification of populations will also provide more statistical power more upstream in drug trials. However, the optimal benefits from the current explosion of ‘data mining’ will only be realised when the basic data are made and kept publicly accessible, while at the same time safeguarding the protection of intellectual property arising from downstream inventions. This is one of the goals of HUGO, the international Human Genome Organisation, established 10 years ago to assist coordinating data acquisition and exchange and societal implementation of the genome project. Additional points of attention in this historic endeavour are the prevention of stigmatisation and discrimination and the safeguarding of a worldwide balance in the contribution by—and benefits to— different populations, while respecting the diversity in cultures and traditions. S2 GENOME-WIDE EXPRESSION PROFILING USING cDNA MICROARRAYS Van Hummelen P Flanders Institute for Biotechnology, MicroArray Facility, University of Leuven, Belgium With the finishing of the first draft sequence of the human genome, a very exciting era, the so-called Post-Genomic Era, has begun. Just looking at the new words that arose in the last couple of years, like Genome, Transcriptome, Proteome, Metabolome, Physiome, it is clear that research in life sciences is progressing exponentially. Over the past decade, large-scale systematic sequencing of cDNA libraries has provided an initial description of the transcriptome: the entire set of gene transcripts of man and several animal and plant organisms. As an example, in the UNIGENE-database there are currently 3, 3 million human sequences that can be clustered into 22,000 known genes and 76,000 candidate genes. With such large repositories of data and physical clones, large-scale gene searches and high throughput functional analyses are now possible. Still, identifying genes or their function remains a difficult task with current techniques.

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Recent advances in materials, optics, electronics, robotics, chemistry, genetic engineering and informatics have permitted the development of integrated platforms such as the MicroArray/DNA chip technology. Microarray analysis is a powerful way to study tens of thousands of transcripts in parallel, in a variety of normal and pathological conditions. Also VIB recently started a core facility to give researcher the opportunity to use microarrays and to participate in the current race for functional annotation of the genome. Currently, 22,000 mouse, 18,000 human and 6,000 arabidopsis clones are ready for analysis. In this presentation, examples of microarray applications and the data-analysis will be presented and discussed. S3 GEL-FREE PROTEOME ANALYSIS Gevaert K, Van Damme J, Thomas GR, Demol H, Staes A, Puype M, Martens L, Goethals M, and Vandekerckhove J Department of Medical Protein Research, Flanders Interuniversity Institute for Biotechnology, Ghent University, Belgium We have developed a new type of proteomics, which uses selected subsets of peptides for protein identification. A protein mixture is digested in solution with a highly specific protease. The generated peptide mixture is fractionated on a RP-HPLC column. The separation properties of a highly representative set of peptides in the collected fractions are chemically and/or enzymatically changed, such that they are isolated during a second separation step, which is identical or similar to the first one. The isolated peptides are then used to identify their precursors by mass spectrometry. Combining primary fractions during the secondary runs, decreases the analysis time and results in high-throughput proteomics. We have called this technique combined fractional diagonal chromatography (COFRADIC). Sets of peptides that are isolated by COFRADIC include Met-containing peptides, in vivo blocked and/or free protein amino termini. The latter increases the proteome coverage, since each protein is represented by only one peptide, thus decreasing the sample’s complexity for analysis. In one of the first studies, we analysed a protein preparation out of fifty million E. coli cells, isolated Met-containing peptides and used these for protein identification. A total of 767 different E. coli proteins were identified, which is ten times the number of proteins identified after ‘classical’ 2-D PAGE, using the same amount of material. For a second study, Met-containing peptides from a tryptic digest of total, unfractionated human plasma were isolated. Automated LC-MS/MS-analysis of these peptides identified, next to the highly abundant known plasma proteins, low abundant proteins of which it has not been shown before that they are present in plasma. In yet another example we used COFRADIC to specifically isolate amino terminal peptides from a tryptic digest of a cytosolic and membrane skeleton preparation of human platelets, and

demonstrated the high dynamic range of the technique by the identification of low abundant proteins (kinases and phosphatases), hydrophobic proteins (integral membrane proteins) next to high abundant ‘household’ and structural proteins. S4 COMPREHENSIVE DNA ANALYSIS USING PYROSEQUENCING TECHNOLOGY Ingemarsson B Pyrosequencing AB, Uppsala, Sweden PyrosequencingIM,is a fast and accurate technology for analysis of short to medium length DNA sequences. It is a non-electrophoretic sequencing method based on luminometric real-time detection of pyrophosphate released upon nucleotide incorporation by DNA polymerase. Samples are sequenced and analyzed in a standard microtiter plate format, without any need for labeled primers or nucleotides. The technique is well established for rapid genotyping of single nucleotide polymorphisms (SNPs). High accuracy is achived by polymerase-catalyzed incorporation of nucleotides at the polymorphic positions as well as adjacent nucleotides. The non-variant positions serve as internal controls and allow for automatic quality assessment of each analyzed sample. Single well multiplex genotyping on pooled simplex or multiplex PCR products can be accurately performed for SNPs and insertion/deletion polymorphisms. The close correlation between nucleotide incorporation/pyrophosphate release and light detection, makes Pyrosequencing technology suitable for quantitative applications such as, allele frequency determination, assessment of gene copy number, analysis of splice mutations and CpG methylation, genotyping in mixed cell populations or polyploidic genomes, as well as for determination of viral load. The technology can also be used for sequence identification/verification and de novo sequencing of 20–50 nucleotides in less than one hour. Hence, it can be used for a number of applications including, analysis of mutation hot spot areas, cDNA re-sequencing, virus and bacteria identification/typing, as well as resistance typing. Pyrosequencing AB has developed complete systems for low to high troughput demands, which include instrument, optimized reagent kits and dedicated software.

Symposium 2: The Genetics of Alcohol Dependence S5 PHENOTYPIC HETEROGENEITY AND LINKAGE MAPPING IN COGA Reich T and Hinrichs T Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri The Collaborative Study on the Genetics of Alcoholism is an eight center study sponsored by NIAAA to characterize genes that increase or decrease susceptibility to develop the

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disorder. To accomplish this goal a large family study and a genetic linkage study was conducted. Because alcohol dependence is extremely variable, a wide variety of phenotypes that are correlated with familial alcoholism were measured. These included putative endophenotypes such as the EEG and the ERP CNS signals. Our study includes 257 families with approximately 2400 subjects who were genotyped with a 10 cM genome screen. Quantitative and qualitative phenotypes were studied. Linkage analyses were remarkable in that different groups of phenotypes gave evidence for linkage at different chromosomal regions. On chromosome 1 the same region gave evidence for linkage with alcohol dependence, cocaine and marijuana dependence, a beta EEG signal, alcoholism and depression and subjective responses to ethanol (SRE). On chromosome 4 (2 regions). Evidence for linkage was found with many EEG measures, an ‘unaffected’ phenotype, maximum number of drinks in a day, and MAO B platelet activity. Other phenotypic clusters were found on chromosome 2, 7, and 15. In each case the distribution of phenotypes is different. Although the number of statistical tests is large, these data support the view that alcoholism and related phenotypes are genetically heterogeneous and that genotypic heterogeneity is reflected in the phenotypic complexity that is clinically observed. S6 GENETIC ANALYSIS OF CHROMOSOME 4 FOR ALCOHOL-RELATED PHENOTYPES Edenberg HJ, Dick DM, Xuei X, Foroud T, and COGA Collaborators Department of Biochemistry and Molecular Biology and Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana Studies from the COGA project point to two different regions of chromosome 4 that appear to contain genes affecting alcohol-related phenotypes; both regions contain attractive candidate genes. There is evidence for a gene or genes on chromosome 4q that influence (s) several phenotypes related to risk for alcoholism: a protective effect, a limitation on the maximum amount of alcohol consumed, and an interaction between risk and electrophysiology. This region of 4q contains the alcohol dehydrogenase gene cluster, which includes genes that have been shown to affect the risk for alcoholism. A region of 4p that contains a cluster of GABA (A) receptor genes has provided weak but consistent evidence for an effect upon the risk for alcoholism, as well as very strong evidence for an effect on brain oscillations. Genomic data are still fragmentary in the 4p region containing GABA (A) receptor genes. We have examined many single nucleotide polymorphisms (SNPs) in these regions for linkage and linkage disequilibrium, in an attempt to identify genes that affect the phenotypes. SNPs were identified either by DNA sequencing or from public databases, and were assayed by a modified single nucleotide extension and mass spectrometry. Multiple

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SNPs were assayed across each of the candidate genes. Linkage disequilibrium among the SNPs themselves provides information about structures of these genomic regions, and allows more powerful linkage disequilibrium mapping of these phenotypes using haplotypes. These analyses provide evidence for linkage disequilibrium between candidate genes in these regions and alcoholism-related phenotypes. In particular, there is strong evidence for a role of variations in the GABRA2 gene in modulating the risk for alcoholism. S7 A SUSCEPTIBILITY LOCUS FOR ALCOHOLISM AND RELATED PHENOTYPES ON CHROMOSOME 1: INTEGRATING GENETIC AND PHYSICAL MAPS TO REFINE LINKAGE AND CANDIDATE GENE ANALYSIS Kwon JM,1 Hinrichs AL,1 Wang J,1 Wu W,1 Meyers D,1 Stock H1 Li T-K,2 Hesselbrock V,3 Crowe R,4 Nurnberger J,2 Schuckit M,5 Begleiter H,6 Reich T,1 and Goate AM1 1 Departments of Neurology, Psychiatry and Genetics, Washington University School of Medicine, St. Louis, Missouri 2 Department of Psychiatry, Indiana University School of Medicine, Indianapolis, Indiana 3 Department of Psychiatry, University of Connecticut School of Medicine, Farmington, Connecticut 4 Department of Psychiatry, University of Iowa School of Medicine, Iowa City, Iowa 5 Department of Psychiatry, UCSD School of Medicine, La Jolla, California 6 Department of Psychiatry, SUNY Health Science Center at Brooklyn, Brooklyn, New York The Collaborative Study of the Genetics of Alcoholism (COGA) has reported a susceptibility locus for alcohol dependence on chromosome 1. In addition, cocaine and marijuana dependence, alcohol dependence or depression, low level of response to alcohol and amplitude of the EEG alpha wave map within the same 20 cM interval between D1S2613 and D1S1588. We have embarked on a systematic examination of single nucleotide polymorphisms (SNPs) in the genomic sequence within and flanking the candidate genes of interest in this region. One candidate gene, phosphodiesterase 4B (PDE4B), is the human homologue of the Drosophila gene dunce, a gene known to be involved in an ethanol responsive pathway in fruit flies. The longest transcript of PDE4B spans over 500 kb of genomic sequence. We identified nucleotide polymorphisms in PDE4B using the public databases and by sequencing the coding region in 10 individuals (5 cases and 5 controls). Nine SNPs were selected for further genotyping experiments in 142 affected-offspring/ parent trios derived from COGA families. While no single SNP was associated with alcohol dependence, haplotype analysis using TRANSMIT reveals that there are haplotypes associated with the development of alcoholism. This supports

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the hypothesis that PDE4B or a gene close by is a susceptibility gene for alcoholism. S8 BIOLOGICAL ENDOPHENOTYPES IN PSYCHIATRIC GENETICS Begleiter H and Porjesz B Department of Psychiatry and Neuroscience, State University of New York, Health Science Center, Brooklyn, New York The use of biological features provides intermediate phenotypes of fundamental utility in searching for genes involved in psychiatric disorders. We have focused on brain oscillations, such as the beta EEG frequency, which has been studied extensively in vitro as well as in vivo. The results in both cases are strikingly similar, and elucidate fundamental biological mechanisms, which can be of value in humans. Fast synaptic inhibition in the mammalian brain is mediated largely by activation of GABAA receptors. Although the recording of electrical oscillations from a neural population reflects the firing of multiple excitatory pyramidal cells, the mechanism underlying beta and gamma oscillations depends on the firing pattern of a network of inhibitory neurons. It will be demonstrated that an active network of inhibitory GABAA neurons provides the pacemaker for beta oscillations. Finally we will report a linkage disequilibrium between the beta frequency of the human EEG and a GABAA receptor gene locus.

Symposium 3: Neurodegenerative Brain Disorders S9 GENETIC EPIDEMIOLOGY OF ALZHEIMER DEMENTIA van Duijn CM Department of Epidemiology & Biostatistics, Erasmus University MC, Rotterdam, The Netherlands In recent years, considerable progress has been made in unravelling the genetic aetiology of Alzheimer’s disease (AD), the major cause of dementia. Three genes have been identified involved in the autosomal dominant forms of early-onset AD, the ß-amyloid precursor protein gene (APP) and two homologous genes presenilin 1 (PSEN1) and presenilin 2 (PSEN2). Mutations in each of these genes have been found to be rare, even in patients with an early onset of AD ( 7%) weight gain (P ¼ 0.002, relative risk 3.45). The protective effect of the 759Tallele was also apparent by six weeks in the subgroups of patients receiving risperidone (P < 0.02) and chlorpromazine (P < 0.01). Of the patients switched to clozapine, the increase in BMI over 6 weeks was also associated with genotype (P < 0.05); the effect was far stronger in males than in females. These findings identify an important genetic factor associated with the treatment-induced increase in weight in schizophrenia, and indicate the potential of pharmacogenetics in predicting patient susceptibility to this major side effect limiting antipsychotic drug use. S20 PHARMACOGENETICS IN MOOD DISORDERS: PREDICTORS OF ANTIDEPRESSANTS EFFICACY Serretti A, Zanardi R, Lattuada E, Cusin C, Lorenzi C, Lilli R, Rossini D, Catalano M and Smeraldi E. Department of Psychiatry, Vita-Salute University, San Raffaele Institute, Milan, Italy During the last few years we performed a series of pharmacogenetic studies in mood disorders. We investigated the possible influence of a set of candidate genes as possible

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genetic predictors of antidepressant response efficacy. Four hundred and sixty inpatients were treated with fluvoxamine 300 mg/day (n ¼ 328) or paroxetine 40 mg/day (n ¼ 132) and either placebo or pindolol in a double blind design for 6 weeks. The functional polymorphism in the upstream regulatory region of the serotonin transporter gene (5HTTLPR) (1-3), the A218C gene variant on the tryptophan hydroxylase gene (TPH) (4; 5) and the G-protein beta3subunit (Gbeta3) C825T gene variant (6) were independently associated with SSRIs antidepressant efficacy. The effects of 5-HTTLPR and TPH polymorphisms were more pronounced in subjects not taking pindolol, while this effect was not observed for Gbeta3. The inclusion in the model of baseline depressive scores, polarity, presence of psychotic features and fluvoxamine plasma levels did not influence the observed association. DRD2, DRD4, Mao-A and 5-HT2A gene variants were not associated with outcome. If confirmed, these results may shed light on the genetically determined component of the response to pharmacological treatments, thus helping the clinician to individualize each patient’s therapy according to the genetic pattern. 1) Smeraldi, E., et al., 1998. Mol Psychiatry 3, 508–511. 2) Zanardi, R., et al., 2000. J Clin Psychopharmacol 20, 105–107. 3) Zanardi, R., et al., 2001. Biol Psychiatry 50, 323–330. 4) Serretti, A., et al., 2001. Mol Psychiatry 6, 586–592. 5) Serretti, A., et al., 2001. Eur Neuropsychopharmacol 11, 375–380. 6) Serretti, A., et al., submitted.

Symposium 6: Contribution of Mouse Mutants as Models for Affective Disorders S21 USE OF MUTANT MOUSE MODELS IN HYPOTHALAMIC-PITUITARY-ADRENAL AXIS RESEARCH Reul JMHM. Section of Neuropsychopharmacology, Max Planck Institute of Psychiatry, Munich, Germany Disturbances in the regulation of the hypothalamic-pituitaryadrenal (HPA) axis are often seen in major depressive disorders. Mostly, this neuroendocrine system is hyperactive due to both an enhanced hypothalamic-pituitary drive and an impaired negative feedback efficacy of glucocorticoids. HPA axis normalization seems to be a prerequisite for a stable remission of the clinical symptomatology after antidepressant treatment. Thus, the HPA axis is of critical importance for major depression. In rats, antidepressants indeed attenuate HPA activity by upregulating hippocampal mineralocorticoid receptors (MRs). MR is one of the two corticosteroid receptor types, the other one is the glucocorticoid receptor [GR; Reul et al. 2000: Eur J Pharm 405:235]. Together, they mediate glucocorticoid action in the brain, MR mediating the hippocampal tonic inhibition of HPA activity and GR mediating the negative feedback action of

elevated glucocorticoid levels. This concept is based on pharmacological studies which were confirmed by studies on mice with functional MR and GR deletions. Corticotropinreleasing factor (CRF), its related peptide urocortin (Ucn) and the CRF receptors (CRF1 and CRF2) also play a pivotal role in HPA regulation. Recently, the CRF-CRF receptor system has expanded due to the discovery of two additional -CRF2-specific-ligands being Ucn II and Ucn III [For review: Reul and Holsboer 2002: Curr Opin Pharmacol 2:23]. Studies on mice with functional deletions of CRF1 or CRF2 suggest that overall these receptors act in an antagonistic manner: such that CRF1 activates and CRF2 attenuates the HPA response to stress. Recently, the complexity of HPA regulation was further boosted by the discovery that CRF directly interacts with MR at the hippocampal level with functional consequences for HPA regulation [Gesing et al., 2001: J Neurosci 21:4822]. Gene deletion models will be helpful to investigate the complex interactions between the CRF receptor and the corticosteroid receptor systems in the elucidation of the etiology of affective disorders. S22 IS THE 5-HT1A RECEPTOR KNOCKOUT MOUSE AN ANIMAL MODEL OF ANXIETY? Olivier B1,2 and Pattij T1 1 Department of Psychopharmacology, Utrecht Institute of Pharmaceutical Sciences, Utrecht University, The Netherlands. 2 Department of Psychiatry, Yale University School of Medicine, New Haven The 5-HT1A KO mouse has been made in three different genetic backgrounds and all three strains are reported more anxious than the corresponding Wildtypes. We studied the 5HT1A KO mouse in a 129Sv-background and could not replicate an anxious phenotype in various standard anxiety paradigms including open field, light-dark test, elevated plus maze and stress-induced hyperthermia. Moreover, 5-HT1A KO mice showed normal circadian rhythmicity in, and absolute levels of heart rate and body temperature under normal daily 12 h light-12 h dark conditions. However, under specific experimental conditions we found evidence that the 5-HT1A KO-mice showed an enhanced stress or anxiety response. When telemetrically measured, 5-HT1A KO mice showed an enhanced tachycardia and core body temperature response either when undergoing the stress of an intraperitoneal injection procedure or when placed in a novel cage. Behaviorally, KO mice also displayed ‘anxiogenic-like’ behavior in the latter situation. 5-HT1A KO mice also showed a differential anxiogenic-like response in a defensive burying paradigm compared to WT mice. 5-HT1A KO mice did not differ in their pharmacological response to various anxiolytics, including benzodiazepines and alcoholin various tests, including SIH, elevated plus maze and barbiturateinduced sleeping. Their HPA-axis response to a stressor also

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appeared normal. It is concluded that the 5-HT1A receptor knockout mouse, at least in a 129Sv background, is not constitutively more anxious. The enhanced anxiety ia only present under specific conditions and stressors. The 5-HT1A receptor seems to play a subtle role in the modulation of anxiety and fear processes. Its absence does not automatically lead to an overt anxious phenotype, but seems dependent on various factors including genetic background and nature of experimental condition and stressor. S23 THE CONTRIBUTION OF MUTANT MICE WITH ALTERED CRH FUNCTION TO UNDERSTANDING OF THE ROLE OF CRH IN AFFECTIVE DISORDERS: AN OVERVIEW AND RECENT FINDINGS Van Gaalen MM,1 and Steckler T2 1 Drug Abuse Program, Research Institute Neurosciences VU, Department of Medical Pharmacology, VUmc, Amsterdam, The Netherlands 2 Johnson & Johnson, Pharmaceutical Research and Development, Beerse, Belgium One of the most frequently observed neuroendocrine alteration seen in depression is an enhanced level of the stress hormone cortisol. It has been hypothesised that corticotropin-releasing hormone (CRH) hypersecretion is, at least in part, responsible for this alteration. Increased CRH levels in the CSF indicate that CRH overactivity is not limited to augmented release of CRH into the portal vein, but is also present in extrahypothalamic brain regions. Moreover, there is strong evidence from animal experiments, linking the CRH system to those types of behaviour also altered in depression, such as to the modulation of anxiety-and depression-related behaviour, and cognitive function. A number of genetically modified mice with mutations in the CRH system have been generated in order to investigate the role of CRH system in more detail. So far, neuroendocrinological and behavioural results have been reported with knockout mice lacking CRH, transgenic mice overproducing CRH, mice with altered activity of the CRH binding protein, and mice lacking the CRH receptor 1, the CRH receptor 2, or both. Findings obtained with such mutants will be discussed. S24 TRANSGENIC APPROACHES TO ANXIETY DISORDERS AND THEIR PHARMACOTHERAPY: FOCUS ON GABA (A) RECEPTORS Crestani F Institute of Pharmacology & Toxicology, University of Zu¨rich, Switzerland Anxiety disorders, particularly generalised anxiety and panic disorders, rank among the most prominent psychiatric conditions. The neurobiology of anxiety is poorly understood. The deletion of the gamma 2 subunit of GABA (A) receptors by gene targeting resulted in a partial receptor function

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impairment in mice heterozygous at the gamma 2 locus. The gamma 2 þ /0 mice displayed an anxiety-like behaviour evidenced by a heightened reactivity toward naturally aversive contextual stimuli and toward learned negative stimuli associations. These gamma 2 þ /0 mice provide a suitable model to analyse the neural circuits that mediate cognitive anxiety. The pharmacotherapy of anxiety disorders is mainly based on the treatment with benzodiazepines. Four diazepam-sensitive GABA (A) receptors containing the alpha 1, alpha 2, alpha 3, and/or alpha 5 subunit have been identified. These receptors can be rendered silent to diazepam by introducing a histidine-to-arginine point mutation at a conserved position in the a-subunit gene. Using a similar mutationinduced molecular switch approach in vivo, mice containing novel alpha 1 (H101R)- or alpha 2 (H101R)-receptors diazepam insensitive were generated. The analysis of the behavioural effects of diazepam in these knock in mice revealed the functional significance of the GABA (A) receptors. Notably the alpha 2-GABA (A) receptor has been identified as the selective molecular substrate that mediates the anxiolytic action of diazepam while the alpha 1-GABA (A) receptor play a major role in mediating its sedative and anticonvulsant properties. Thus, theses animal models provide insight into the mechanisms that may underlie the pathophysiology and pharmacotherapy of anxiety disorders.

Educational Workshop 1: Research Methods in Psychiatric Genetics E1 PATTERNS OF INHERITANCE IN BEHAVIOURAL DISORDERS AND GENE-ENVIRONMENT INTERPLAY McGuffin P Social Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King’s College London, UK Most common familial disorders do not show simple mendelian patterns of transmission. Furthermore there is strong evidence from twin studies that most major psychiatric disorders involve non-genetic as well as genetic factors. The fundamentals of quantitative genetic models will be explored starting with the general single locus model and going onto oligogenic and polygenic threshold models. The various types of gene-environment interplay, co-action, interaction and co-variation will be considered. E2 MOLECULAR GENETICS O’Donovan MC University of Wales College of Medicine, Psychological Medicine, Cardiff, UK This presentation aims to provide an overview of genomics and how knowledge of the genome and modern methods of molecular genetic analyses are applied to identifying genes for complex diseases. The presentation will cover genome

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organisation, human variation and its effects, linkage and association, and the conduct of molecular genetic studies. The presentation will be broad but not detailed and is aimed towards an audience with little prior knowledge of the subject. E3 LINKAGE AND ASSOCIATION METHODS Strauch K Institute for Medical Biometry, Informatics, and Epidemiology, University of Bonn, Germany Genetic epidemiology aims at the identification and characterization of genes responsible for inherited diseases. The first step towards the identification of a gene is its localization, or mapping. One possible strategy to map a disease gene with previously unknown position is to perform a linkage analysis. With this approach, it is tested whether marker and disease locus co-segregate within families. Linkage analysis is often performed in the context of a genome scan, where 300 to 500 highly polymorphic microsatellite markers are typed throughout the genome. For parametric (modelbased) linkage analysis, it is necessary to specify a disease model prior to the analysis; this is not the case for nonparametric (model-free) analysis. However, for the latter, a particular statistic needs to be selected which assesses the sharing of alleles among affected individuals in the pedigree. Linkage analysis, in general, is useful for mapping a gene to a certain chromosomal region, but not for pinpointing its exact position. When the fine-mapping of a gene is at issue, association analysis is the method of choice. Tests for association may as well be performed in the context of a candidate gene study. With association analysis, it is examined whether a certain allele occurs more (or less) frequently in affecteds than in unaffecteds. Contrary to linkage analysis, association analysis looks at unrelated individuals. With the case-control design, affected and unaffected singletons need to be collected. An alternative approach is to take into account parentchild trios where the affected child represents the case and a fictitious individual, who carries the nontransmitted parental alleles, represents the internal control. Using these so-called Falk-Rubinstein trios has the advantage that spurious results due to population stratification, which may be an issue in a classical case-control study, are avoided. In this talk, an introduction to linkage and association analysis will be given. Difficulties arising in the context of mapping genetically complex traits will be a special focus.

Educational Workshop 2: State of Art on Major Brain Diseases E4 THE GENETICS OF THE MAJOR PSYCHOSES Owen MJ Department of Psychological Medicine, UWCM, Cardiff, UK This lecture will review recent advances in the genetics of schizophrenia and bipolar disorder, describe work using

linkage and association studies and review reports of schizophrenia assocated with chromosomal abnormalities and mendelain disorders. Meta-analyses of data from genomewide linkage studies will be presented and the regions likely to contain genes identified. The problems facing researchers attempting to identify disease genes will be described and the optimal approaches for this work discussed. E5 HOW MIGHT GENETIC MECHANISMS WORK TO CAUSE AUTISM? Folstein SE Tufts-New England Medical Center, Department of Psychiatry, Boston Twin and family studies provide strong evidence that autism has a largely genetic etiology. The pattern of familial aggregation found in these studies suggest that in individual families, a moderate number of genes act together cause the phenotype. However, it is unlikely that the same group of genes act in all families. Thus, the total number of genes involved could be large. The key to finding genes in for disorders with considerable locus heterogeneity is to detect genetically more homogeneous sub samples. When a subsample is subjected to linkage analysis, the linkage signals for the genes involved are not obscured by ‘noise’ caused by non-linked families. What phenotypic characteristics of autism are likely to reflect underlying genetic heterogeneity and can thus be used to divide families into such genetically homogeneous subsets? We propose that the most likely candidates are traits—biochemical, physical, or behavioral—that (1) show variation in persons with autism, (2) are also found in non-autistic family members of autistic probands more often than controls, and (3) aggregate in particular families, rather than being distributed randomly among autism families. Data will be presented from our sample of multiplex families that suggest the value of this approach. E6 GENETIC EPILEPSIES AND GENETICS OF THE EPILEPSIES Pandolfo M Department of Neurology, Hoˆpital Erasme, Free University of Brussels, Belgium Relatives of individuals with primary, non-lesional (idiopathic) epilepsy have an increased risk of developing seizures, but lower than would be expected for a monogenic trait. The highest risk (16–18%) is for those who have a sibling and a parent with idiopathic generalized epilepsy (IGE). MZ twins have a very high concordance rate for IGE and have the same syndrome. Concordance rates are much lower in DZ twins and DZ twins may have different syndromes. These data demonstrate an almost complete genetic etiology of IGE, indicate that common variants of several interacting genes are likely to be involved, and suggest that

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each specific IGE syndrome is the result of a specific set of alleles. This concept would account for the notable phenotypic heterogeneity often observed in IGE families. Genome scans have been performed with IGE families with the assumption of complex inheritance, proposing a number of candidate regions. However, the identification of rare monogenic syndromes has been critical for our understanding of the genetic basis of idiopathic epilepsy, generalized as well as partial. Mutations have been discovered in voltage- and ligand-gated ion channel genes, including the neuronal nicotinic acetylcholine receptor, the GABA-A receptor and voltage-gated Na þ , K þ and Cl channels. A few non-ion channel genes have also been found to cause human epilepsies, including the LGI1 gene in temporal lobe epilepsy with auditory symptoms. Less is currently known about genetic polymorphisms that act as risk factors for the common cases with complex inheritance. A Cl channel gene on chromosome 3 may be such a gene, in addition to carrying major mutations in a few families with mendelian inheritance. We identified polymorphisms in a Ca2 þ dependent K þ channel gene on chromosome 3 as possible risk factors for epilepsy. Genetic association studies with candidate genes are increasingly being proposed as an approach with high potential to identify genes contributing to the common, types of epilepsy. A very rigorous methodology needs to be used in order to prevent a number of pitfalls, due in particular to population admixture.

Educational Workshop 3: Psychopharmacogenetics E7 MONOAMINE TRANSPORTERS AND BIOLOGICAL MARKERS OF MOOD DISORDERS Brunello N Department of Pharmaceutical Sciences, University of Modena and Reggio Emilia, Italy A major goal in the study of neuropsychiatric disorders has been to identify underlying mechanisms of brain dysfunction with the expectation that these insights may allow a better diagnosis, prevention and effective treatments for these disorders. Most of neurological, neuropsychiatric and neurodegenerative disorders have been associated with alterations in the neurotransmission cascade. In this context, the complete elucidation of neurotransmitter transporter functions can be of strategic importance for the development of new therapies. Indeed, a wide range of pharmacological agents are known to act as neurotransmitter transport inhibitors. The reduced serotonin transport in platelets and brain in depressed and suicidal patients and the efficacy of selective serotonin reuptake inhibitors (SSRI) in the treatment of depression are compelling evidences in support of the involvement of serotonin transporter (SERT) in the aetiology of mood disorders. Decreased serotonin brain levels in

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patients with disorders of the effective spectrum may reflect a structural defect and/or dysregulation of the transporter. The gene coding for the human SERT has been recently cloned and found to have a promotor region deletion associated with reduced transcriptional efficienty and decreased expression of SER protein. The recent observation that both the initial affinity and genotype of SERT may contribute to the variation in the outcome of treatment strengthened the ‘serotonin hypothesis’ of mood disorders. However, more genetic and more molecular studies on neurotransmitter transporters in relation with psychiatric diseases need to be performed to get really definitive and clear-cut data regarding the association of a given polymorphism and one ore several of mood disorders. E8 GENETICS AND GENOMICS IN NEUROPSYCHOPHARMACOLOGY Kelsoe JR Departments of Psychiatry, University of California, San Diego and San Diego VA Healthcare System, La Jolla, California Psychopharmacology has been hampered by the lack of a fundamental understanding of pathophysiology and disease mechanism. Hence, our current diagnostic system is comprised of behavioral syndromes rather than diagnoses based on disease mechanisms, and there is little framework for the rational design of truly novel therapeutics. The Human Genome Project has recently provided a powerful array of new tools for the identification of disease genes and pathways. The power of these tools lies in their ability to comprehensively survey all genes, and their lack of need for a priori hypotheses. Two of these tools, positional cloning and microarray expression profiling will be described and their application to the identification of psychiatric disease genes discussed. An example of their combined use to identify a possible gene for bipolar disorder on chromosome 22 will be described. Though the problems presented by complex genetic traits are challenging, these tools promise new insights into disease. In the future, DNA testing may be employed in making a new set of more specific diagnoses based on disease mechanism. These novel diagnoses may then in turn direct the clinician to medications targeted to novel proteins specific to the pathways involved in that mechanism. Genetics and genomics will likely play a major role in the development of this new and more specific psychopharmacology. E9 FROM GENE TO FUNCTION: IMPLICATIONS FOR PHARMACOGENETICS IN PSYCHIATRY Kennedy JL Neuroscience Research Department, CAMH, University of Toronto, Canada There is strong evidence to suggest that genetic variation plays an important role in inter-individual differences in

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response and side effects to medication. Likely both pharmacodynamic and pharmacokinetic factors are involved with any given drug. One method to uncover genes that are relevant to a particular drug’s action is to treat a model system (eg rat or neuronal cell line) with the drug and examine for gene expression differences using microarray or subtraction PCR screening. Complementary to this is the use of knowledge in the pharmacology and neurobiology of the medication in humans to designate candidate genes for specific investigation in responders versus non-responders. The candidate gene variants that affect function of the gene or its protein product have the highest priority for investigation. This presentation will provide demonstrative examples of functional candidate gene variants studied in a variety of response phenotypes. Serotonin and dopamine gene variants in clozapine response will be examined, and in the process pointing to the need for sub-phenotypes. Our data indicating a predictive role for the promoter polymorphism of the serotonin transporter gene in the induction of mania during antidepressant treatment will be presented. The antipsychotic side effect of tardive dyskinesia and its association with the putatively functional ser9gly variant of the dopamine D3 receptor will be critically examined, as well as the role of the variably inducible CYP1A2 gene. Finally, our preliminary data suggest that the functional variant in the tumor necrosis factor gene may be involved in clozapine induced weight gain. To the extent that the above data become more verified and replicated, the field of psychiatry will move closer to clinically meaningful tests that will be useful in deciding the best drug for each individual patient.

Slide Session 1: Bipolar I O1 A GENOME-WIDE SCAN IN EXTENDED FAMILIES WITH BIPOLAR DISORDER FROM AN ISOLATED REGION IN NORTH SWEDEN REVEALS CANDIDATE LOCI ON CHROMOSOMES 2Q AND 9Q Claes S,1,2 Del-Favero J,1 Paterson Ad,3 Van Gestel S,1 Van Duijn C,4 Van Broeckhoven C,1 and Adolfsson R5 1 Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Antwerp (UIA), Belgium. 2 Department of Psychiatry, University Hospital Antwerp (UZA), Edegem, Belgium. 3 Program in Genetics and Genomic Biology, The Hospital for Sick Children and Departments of Public Health Sciences and Psychiatry, University of Toronto, Canada. 4 Department of Epidemiology & Biostatistics, Erasmus University Medical School, Rotterdam, The Netherlands. 5 Department of Psychiatry, University of Umea˚, Sweden We present data of a genome-wide scan in 9 multiplex Swedish families with bipolar disorder. These families come from the Va¨sterbotten region in the North of Sweden, which is

genetically relatively isolated. This probably reduces the number of genetic vulnerability factors for bipolar disorder in this sample, maximizing the probability of detecting these genes by linkage analysis. Linkage simulation studies showed an average maximum LOD score of 6.44 in the overall sample assuming a dominant transmission model. A maximal parametric recessive two-point LOD score of 2.47 was obtained with marker D9S290. Multipoint linkage analysis (GENEHUNTER) found suggestive evidence for linkage on chromosome 2q35-q37 (Zmax ¼ 1.98) under a dominant transmission model, and on chromosome 9q32-q34.1 (Zmax ¼ 3.00) assuming recessive inheritance. Nonparametric analyses using GENEHUNTER yielded a maximal NPL-Z score of 3.58 (P ¼ 0.003) at chromosome 2q. Therefore, both the 2q and the 9q regions should be considered candidate regions for bipolar disorder in this population. O2 THE WELLCOME TRUST UK-IRISH BIPOLAR SIB-PAIR GENOME SCREEN: SECOND STAGE FOLLOW UP OF REGIONS ON CHROMOSOMES 3, 4, 7, 12, 17 AND X Middle F,1 Quinn R,1 Gordon-Smith K,1 Heron J,1 Haque S,1 Pelios G,1 Bennett P,1 Lendon C,1 Jones L,1* Jones I,1 Gill M,2 and Craddock N1 1 Molecular Psychiatry Group, Division of Neuroscience, University of Birmingham, UK. 2 Department of Psychiatry, Trinity College, Dublin, Eire. The Wellcome Trust UK-Irish Bipolar Sib-pair Study is a two-stage collaborative genome screen funded by the Wellcome Trust involving the University of Birmingham, UK, and Trinity College, Dublin, Eire. The first stage screening sample included 509 subjects from 151 families, consisting of 154 narrowly defined affected pairs (DSMIV BPI) and 258 broadly defined affected pairs (DSMIV BPI, BPII, SA BP, BP NOS or MDD (R)). All individuals were typed for 398 microsatellite markers (mean spacing 9.6 cM) and the primary analysis used MAPMAKER/SIBS under the narrowest model of affection status. There was no evidence of genes of major effect.19 points across the genome were identified where MLS exceeded a value set for follow up in our second stage (MLS >0.74; equivalent to nominal point wise P < 0.05). These points were on chromosomes 2, 3, 4, 6, 7, 9, 10, 12, 17, 18, X and included some regions that overlap with previous linkage reports within Bipolar Disorder and other psychiatric illnesses. We have now followed up these regions according to our predetermined strategy: This has involved both increasing marker density (to 5 cM) and the addition of a second stage sample set containing 362 further individuals (enlarging the sample to 220 narrowly defined affected pairs and 396 broadly defined affected pairs). Regions on chromosomes 3, 4, 7, 12, 17 and X have been typed in the Birmingham laboratory. Completed analysis reveals an increase of support on chromosomes 4 (MLS 1.7

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at D4S392), 7 (MLS 1.7 at D7S630) and X (MLS 1.4 at DXS1214); data analysis for chromosomes 3, 12, 17 is ongoing. O3 A GENOME-WIDE SCAN OF THE AGE AT ONSET OF MANIA YIELDS THREE POTENTIAL SUSCEPTIBILITY LOCI Su J,1 Faraone S,1 and Tsuang M2 1 Department of Psychiatry, Harvard Medical School, Boston, Massachusetts 2 Harvard Institute of Psychiatric Epidemiology and Genetics, Boston, Massachusetts Genetic epidemiologic studies of bipolar disorder suggest that variability in the age at onset of mania may have neurobiologic correlates and that earlier onset may be associated with a greater genetic loading. Data are presented on a genome-wide scan of 538 genotyped people in 97 families with bipolar disorder. Exact likelihoods of IBD sharing were calculated for each relative pair within each pedigree using Genehunter. These likelihoods were then used in a multipoint variance components linkage analysis in SOLAR. Two quantitative traits, the log transformation of the age of onset (AOS) of mania and the log transformation of the AOS of depression, were developed. The AOS of mania had significant heritability (40%, P ¼.004) while the AOS of depression did not (P > 0.1). Multipoint linkage analysis was only performed on the AOS of mania given its higher heritability. Three chromosomal regions yielded multipoint LOD scores greater than 2.5: markers DLS1292, GATA31B, and GATA153 on chromosomes 12, 14, and 15 respectively. We also describe the clinical correlates of AOS in mania and discuss how these concur with prior work in the areas.

O4 GENOME-WIDE SCAN OF 153 BIPOLAR MULTIPLEX PEDIGREES ASCERTAINED THROUGH THE NIMH GENETICS INITIATIVE FOR BIPOLAR DISORDER McInnis MG,1 Dick D,2 MacKinnon DF,1 McMahon FJ,3 Potash JB,1 Nunberger J Jr,2 Gershon ES,3 Edenberg H,2 Reich T,4 Rice J,4 Simpson SG,1 Willour VL,1 DePaulo JR,1 Zandi PP,1 and Foroud T2 1 Johns Hopkins University, Baltimore, Maryland 2 Indiana University, Indianapolis, Indianadiana 3 University of Chicago, Chicago, Illinois 4 Washington University, St Louis, Missouri A 4 center genetic collaborative effort has studied bipolar (BP) multiplex pedigrees ascertained through a bipolar I proband with at least one BPI affected sibling and 2 additional living siblings. The evaluation used the Diagnostic Interview for Genetic Studies (DIGS), which generates both DSM and RDC diagnoses. The current analyses consist of 513 polymorphic markers in 899 subjects from 153 pedigrees.

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The sample included 334 BPI, 115 BPII (with recurrent major depression [RMD]), 57 schizoaffective manic (SAM) and 141 subjects with recurrent major depression. Analyses were performed under 3 affection status models (ASM): ASM I included BPI and SAM (391 subjects); ASM II included BPI, SAM, and BPII with RMD (506 subjects); ASM III included BPI, SAM, BPII with RMD, and RMD (647 subjects). The method of analysis was a nonparametric analysis of allele sharing among affected relative pairs; ASMI 284 pairs, ASMII 529 pairs, and ASMIII 894 affected relative pairs. There were 12 regions identified with nominally increased evidence of allele sharing among relative pairs. The 3 most significant regions were on chromosome 16p13 (P ¼ 0.0004), 20p12 (P ¼ 0.0037), and 6q24 (P ¼ 0.0056). The chromosome 16 and 20 findings have been reported previously in bipolar disorder and the chromosome 6 region has been reported in a genetic study of schizophrenia.

O5 LINKAGE DISEQUILIBRIUM MAPPING OF POSITIONAL CANDIDATE GENES IN BIPOLAR DISORDER Petryshen T,2 McInnis M,3 Tahl T,2 Aldinger A,2 Daly M,2 DePaulo R,3 Lander ES,2 and Sklar P1,2 1 Massachusetts General Hospital, Boston, Massachusetts 2 Whitehead Institute/MIT Center for Genome Research, Cambridge, Massachusetts 3 Johns Hopkins University School of Medicine, Baltimore, Maryland We have taken a linkage disequilibrium (LD) based approach to mapping using nearby SNP markers as proxies for the actual disease causing SNP. The extent of LD has been delineated in several population samples (Reich, Nature, et al., 2001; Gabriel, Science 2002, in press) and is sufficient for LD mapping. Regional linkage in bipolar disorder of high likelihood was identified by reviewing all published genomewide linkage scans. A list of positive markers reported by each investigator was compiled. For each marker or position, corresponding markers and positions in the other studies were determined by approximation using the Marshfield or CHLC maps. Candidate genes were chosen in the 6 regions with lod >1 in three or more studies (5q, 8q, 10q, 11q, 18q, 21q). In this initial phase, thirty candidate genes were chosen covering approximately 3 Mb of physical distance. SNPs were identified within the genes and the immediately surrounding sequence from dbSNP. Each SNP was genotyped by MassArray technology in a panel of 96 multigenerational CEPH pedigrees. Quality of genotyping was assessed by identifying deviations from H-W equilibrium, Mendel errors, or low overall genotyping. Haplotype maps were constructed for each gene by computing the population genetic parameter D0 and the lod score for all pair wise combinations of

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SNPs within the gene. For each haplotype block within the gene, all haplotypes present at greater than 2% in the CEPH population were compiled. A minimal set of SNPs that could be used to fully characterize the haplotype diversity within the block was constructed (haplotype tag SNPs). This set of haplotype tag SNPs was then genotyped in bipolar proband-parent trios. Analyses of individual SNPs by TDT as well as haplotype frequencies in the transmitted and untransmitted haplotypes were computed. We have provided evidence that linkage mapping using a haplotype tag SNPs is a feasible approach to identifying bipolar risk genes. O6 CORRELATION BETWEEN MOOD DISORDER AND FITNESS Perri C,1 DeVito O,1 Foncin JF,2 and Bruni AC1 1 Centro Regionale di Neurogenetica, Lamezia T, Italy 2 Ecole Pratique des Hautes Etudes, Paris, France Is there a correlation between mood disorders and a personality characterized by an expansion of behavior and the ‘‘exploration of the environment’’? We hypothesized that a genotype increases Darwinian fitness and predisposes one to psychiatric symptoms. We selected 95 probands and 220 retrospective cases through history and medical archives. All were genealogically reconstructed; the population from 1606 on was entered in a database. The history of the patients and their ancestors was studied. Probands have a high level of alertness and promptness, high fluency in associating ideas, a greater intensity and persistence in answering to basic and pulsional instincts (hunger, sex, curiosity, creative expressions). They have a potential operating efficiency that in favorable conditions becomes useful, while in negative conditions, characterized by high levels of stress, can lead to the onset of symptoms. Looking at the social background of the ancestors (1810–1870) of 67 probands, the occupations of 403 males were compared to those of 889 subjects of the same population and period. Among the ancestors of the patients, the prevalence of mood disorders predominated in a fraction of the upper social class. Genealogical study of 51 probands and 152 historical cases identified founder couples common to most of them and in particular to one born before 1550. Three later bottleneck couples, were also identified. 99 cases were linked to the first couple (marriage 1724) while 59 and 95 cases linked respectively to the second (1729) and the third (1741) couple. The age at death of each member of the bottleneck couples, siblings and children was acquired as well as the number of descendants.36 matched control couples were used. The number of the descendants was 4 times higher in the 3 bottleneck groups and the age at death was 38.6 vs. 28.5 in the controls. In conclusion, the subpopulation formed by the ancestors of patients, tends to have better fitness than the controls both in terms of survival/reproduction and in terms of social success.

Slide Session 2: Bioinformatics and Technology O7 HOW MANY NON-SYNONYMOUS SNPS ARE AVAILABLE ON PUBLIC DATABASES? Butcher LM, Meaburn EL, Hill L, Plomin R and Schalkwyk L SGDP Research Centre, The Institute of Psychiatry, London, UK Non-synonymous Single Nucleotide Polymorphisms (nsSNPs) change the amino acid sequence of a gene product and are the most likely class of SNP to have functional consequences on phenotype. nsSNPs are especially valuable because they facilitate direct rather than indirect association and thus greatly enhance power in the search for Quantitative Trait Loci (QTLs) of small effect size. Obtaining a good set of nsSNPs is therefore a good starting point for a genome-wide association study, using pooled DNA samples. The primary database of SNPs, dbSNP (http://www.ncbi.nlm.nih.gov/ SNP/), unifies SNP reports from multiple sources, but has only a limited amount of functional information originating from the submitter. PicSNP, (Chang & Fujita, 2001; http:// plaza.umin.ac.jp/hchang/picsnp/) a data base of putative nsSNPs in the human genome is derived from the human genome sequence and is cross referenced to dbSNP, reports 17833 unique nsSNPs in 6441 genes. The experimental usefulness of these putative SNPs depends on their verification status and their frequency in our population of interest. The 17833 nsSNPs were extracted from dbSNP in XML format using the Perl module, XML: Parser. They were selected for nonsynonymity and a frequency of at least 10%, as determined in a Caucasian sample of at least 40 chromosomes. Of the 17833 nsSNPs from PicSNP, 6922 had population data assigned to them in dbSNP. Additionally, the ‘function-class’ of many of these nsSNPs was not consistent with the latest information from dbSNP. The inconsistencies led us to exclude a third of SNPs that had a dbSNP functionclass of ‘intron’, ‘exception’, ‘UTR’, or ‘coding-synonymous’. Of the 226 population samples represented in dbSNP we identified 50 consisting only of Caucasians, and incorporated this into the filtering program. As of 2nd May 2002, the final list (http://sgdp.iop.kcl.ac.uk/leo/SNPlists. html) has 1933 SNPs. O8 SNP MARKER SELECTION FOR ASSOCIATION MAPPING OF COMPLEX TRAITS Jawaid A, Sham P, Makoff A and Asherson P Department of Psychological Medicine, Institute of Psychiatry, King’s College London, UK The cost and efficiency of genome-wide linkage disequilibrium mapping of common disease genes could be greatly improved providing genotyping effort is greatly reduced and informative markers are selected. It is suggested that a subset of SNPs (htSNPs), that tag common haplotypes describing most of the genetic diversity, are identified and combined into

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multi-marker haplotypes. This, it is argued, will provide a more cost-efficient approach by reducing the amount of genotyping, in comparison to single locus studies. To address this issue, we have examined the informativeness of haplotype mapping with htSNPs in comparison to single locus analyses using empirical data on 115 polymorphic SNP markers genotyped across 9 gene regions. We have examined the merits of using htSNPs to: (a) capture the information of the tagged haplotype (b) serve as markers for single locus analyses. We have also selected SNPs on the basis of their minor allele frequencies (MAF) using three cut-offs: (c) MAF >20%, (d) MAF >10%, and (e) MAF >5%. In this analysis, we tested the relative efficiency of the five strategies to detect associations with each of the 115 markers—to simulate the situation where each of the 115 markers in turn could be a functionally significant variant (FSV). The use of htSNPs, when combined in multipoint haplotype analyses, is far better than using the same markers or MAF >20% SNPs in single locus tests of associations. The better overall performance of the haplotype approach than the use of MAF >10% SNPs, (77% versus 65%), is mainly due to its ability to detect very low frequency FSVs (23% versus 0%). For the remaining higher frequency FSVs, combining the 5–19% and 20–50% FSV groups, the two approaches are very similar (92% versus 87%). As expected the most reliable method for the detection of FSVs with allele frequencies greater than 5% is to analyse all SNPs with allele frequencies in the 5–50% range. The use of MAF >10% or MAF >5% SNPs therefore compares favourably with the haplotype approach. O9 SNPBOX: A SOFTWARE PACKAGE FOR THE CONSTRUCTION OF GENOME WIDE HIGH DENSITY SNP MAPS Weckx S, De Rijk P, Van Broeckhoven C and Del-Favero J Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Antwerp, Belgium Single nucleotide polymorphisms (SNPs) are the most frequent variations in DNA and occur about every 1000 to 1500 bp in the human genome. Because of their frequent occurrence and the ease towards automated scoring, SNPs are very useful as genetic markers in complex genetics and pharmacogenomics. We developed a bioinformatics/high throughput approach to construct high density SNP maps of genomic regions. SNPbox is a modular program with a backend database for validating public SNPs as well as searching and validating de novo SNPs. A local database pubSNP is used which consists of adapted data from HGVBASE. To detect public SNPs in the genomic region, pubSNP is queried with the sequence of the candidate region and the output of the BLAST program is parsed into the database. The position of each public SNP found in the query sequence is calculated

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and a primer set is designed using Primer3 for confirmation within the population used with pyrosequencing technology. In an attempt to saturate the candidate region, de novo SNPs can be searched as well. Hereto it’s possible to focus on known exons in the region of interest. The program uses exon-information from the region determined by aligning the genomic DNA and one or more cDNA sequences using Spidey. For each exon one or more targets are determined taking into account the presence of repeats and for each target, a primer pair is designed using Primer3. Targets can also be designed for intronic regions taking into account existing targets and repeats. The primer pairs are used to perform PCR and the resulting amplicons are analysed by DHPLC. Products with aberrant profiles are sequenced on an ABI 3700 sequencer and the raw sequences are analysed using novoSNP, a component of SNPbox which is able to screen the sequences for SNPs. For each de novo SNP found, a primer set is designed with Primer3 for SNP genotyping using pyrosequencing technology. O10 SETTING UP A LARGE SCALE ASSOCIATION STUDY ACROSS A REGION LINKED TO PSYCHIATRIC DISORDERS USING POOLS OF DNA Le Hellard S,1 Ballereau SJ,1 Visscher PM,2 Morris SW,1 Warne SL,1 Torrance HS,1 Muir WJ,1,3 Blackwood DHR,1,3 Porteous DJ,1 and Evans KL1 1 Medical Genetics Section, University of Edinburgh, UK 2 Division of Biological Sciences, University of Edinburgh, UK 3 Department of Psychiatry, University of Edinburgh, UK We have previously reported linkage to chromosome 4p in a large Scottish pedigree that segregates Bipolar Affective Disorder (BPAD) and Unipolar Disorder (UD). This linkage has since been replicated in several independent studies, and we now have access to DNAs from four families showing evidence for linkage to this region. We have also reported an association between schizophrenia (SCZ) and microsatellite markers near the Dopamine Receptor D5, one of the candidate genes from the region. We are now initiating a largescale case-control association study with three different case populations: BPAD, UD and SCZ (see abstract from Evans, KL. et al). The association study aims to cover the whole candidate region with a high density of publicly available single nucleotide polymorphisms (SNPs) and additional SNPs identified by sequencing of candidate genes in linked families. In order to perform this study we need a highthroughput, accurate and cheap method. We chose to perform association studies using pools of DNA, which allow time and cost effective genotyping. We compared the accuracy, efficiency and robustness of three methods of genotyping SNPs on pooled DNAs. We conclude that a) the frequencies of the two alleles in pools should be corrected with a factor

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for unequal allelic amplification, (estimated from the mean ratio of a set of heterozygotes); b) the repeatability of an assay is more important than pinpoint accuracy when estimating allele frequencies; c) the size of a pool has a relatively small effect on the accuracy of allele frequency estimation. In addition, we describe statistical approaches to allow rigorous comparison of DNA pool results. Finally, we describe an extension to our ACeDB database that facilitates management and analysis of the data generated by association studies.

O11 COMPARISON OF MOUTH SWAB DNA AND PEP DNA AS A TEMPLATE FOR GENOTYPING ANALYSIS Xu X, Freeman B, Craig I, Plomin R and Asherson P SGDP, Institute of Psychiatry, London, UK Primer extension pre-amplification (PEP) is a method for amplifying large fractions of the genome from a limited amount of DNA. The PEP technique involves pre-amplification of genomic template with a random 15 base-pair primer, resulting in a 500–1000 fold increase in DNA template. PEP was initially developed to amplify DNA from a single cell, was subsequently evaluated using different amplification protocols and adapted to provide template suitable for PCR. In this study we wished to see whether PEP could provide a general solution to the analysis of large population and epidemiological samples where the collection of blood samples is not feasible and the quantity and/or quality of DNA is a limiting factor. In our own laboratory we have routinely been collecting DNA by mouth swab kits sent and returned in the post and have gathered a total more than 10,000 such samples to date with a reasonable yield (mean ¼ 85 ug/sample). This amount of DNA remains limiting given the number of different phenotypes and genotypes that we envisage investigating. Comparison of mouth swab DNA and PEP DNA was made, as a template for different genotyping analyses of four markers (1) A SNP in the dopamine receptor gene analysed by primer extension (2) A microsatellite marker near to the dopamine D5 receptor gene (3) A variable number tandem repeat in the 3’-untranslated region of the dopamine transporter gene (DAT1) analysed on agarose gel (4) A SNP in the serotonin 1B receptor and analysed by enzyme digestion and visualised on ABI 3100. In each case the genotypes produced from the PEP DNA were the same or better than those produced using non-amplified mouth swab DNA. Each PEP reaction was performed in quadruplicate to ensure adequate coverage of the genome. Only 10 ng of DNA is used in a 50 ml PEP reaction; so we use only 40 ng to give a final volume of 200 ml of PEP reaction products. Of this only 0.6 ml is required to produce high quality genotypes, which approximates to only 60 picograms of DNA per genotype.

O12 EXPRESSION OF THE DOPAMINE TRANSPORTER GENE IS MEDIATED BY GENOTYPE: EVIDENCE FROM BRAIN AND LYMPHOCYTES USING QUANTITATIVE RT-PCR Mill J, Browes C, Craig I, D’Souza U and Asherson P Social, Genetic, and Developmental Research Centre, Institute of Psychiatry, London, UK Genetic association studies provide considerable evidence that the 10-repeat allele of a variable number tandem repeat (VNTR) in the 3’-untranslated region (3’-UTR) of the dopamine transporter gene (DAT1) is associated with a range of psychiatric phenotypes, most notably attention deficit hyperactivity disorder (ADHD). The mechanism for this association is not yet understood, although several lines of evidence implicate variation in gene expression. In vivo studies using SPECT show an increased density of striatal DAT in ADHD probands compared to controls and suggest there may be an association between the VNTR genotype and DAT density. In vitro studies suggest that the VNTR sequence enhances promotor activity and this may be regulated by the number of repeats. In this study we measured DAT1 messenger RNA (mRNA) levels in cerebellum, temporal lobe and lymphocytes using quantitative real-time RT-PCR. Relative to a set of 4 control housekeeping genes (Beta-actin, GAPDH, ribosomal 18S, and Beta-2-microglobulin) we observed that increased levels of DAT1 expression were associated with the number of 10-repeat alleles (brain: P ¼ 0.05; lymphocytes: P ¼ 0.06). These data provide direct evidence that the VNTR, or another polymorphism in linkage disequilibrium with the VNTR, is involved in regulating expression of this gene.

Slide Session 3: Alcoholism O13 ANALYSIS OF AN INFLUENTIAL PEDIGREE IN THE COLLABORATIVE STUDY OF THE GENETICS OF ALCOHOLISM Hinrichs A, Kwon J, Bierut L, Goate A and Reich T Departments of Neurology, Psychiatry and Genetics, Washington University School of Medicine, St. Louis, Missouri Genome wide linkage studies of complex disorders often ascertain large pedigrees with many affected individuals for added efficiency and power. A typical analysis weighs the pedigrees by size or number of affected individuals, but this factor may not be enough to compensate for unusually large or complex pedigrees. For a large study, it may be important to test whether the inclusion or exclusion of individual pedigrees greatly influences results. For example, the Collaborative Study of the Genetics of Alcoholism (COGA) is a large multicenter study, which studies the genetics of alcoholism and related phenotypes. Branches of an ascer-

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tained pedigree are extended through affected individuals (Feighner definite and DSM-IIIR alcohol dependence). Of particular interest is a single pedigree consisting of 11 affected siblings and their offspring. This pedigree can dominate affected sib pair analysis (such as provided by ASPEX) when weighing options are not carefully selected. Even using software designed for extended pedigrees (such as Genehunter), the addition of this pedigree to the overall data set can change linkage signals substantially. For example, on chromosome 2 this pedigree analyzed individually produces an NPL score of 28.8 near D2S379. This high score is due to the transmission of a single haplotype from the father to all affected 11 siblings and their affected offspring. We are currently genotyping more markers in this area to precisely identify the common haplotype. We are also examining the genes in this region and beginning to look for SNPs that may point to a major gene. This may also be a false positive due to a problem at the molecular level (such as an inversion). In either case, this extremely unusual pedigree provides a tremendous influence on overall results and deserves careful attention.

O14 GENOME SCREEN FOR GENES INFLUENCING SUICIDE ATTEMPTS AND SUICIDAL BEHAVIOR IN THE COLLABORATIVE STUDY OF THE GENETICS OF ALCOHOLISM Dick DM,1 Foroud T,1 Schuckit MA,2 Edenberg H,1 Nurnberger JI, Jr3 Goate A,4 Kramer J,5 Hesselbrock V,6 and the COGA collaborators 1 Department of Medical and Molecular Genetics, Indiana University School of Medicine 2 University of California, San Diego 3 Department of Psychiatry, Indiana University School of Medicine 4 Washington University at St. Louis 5 University of Iowa 6 University of Connecticut Alcoholics are at a higher risk of attempting suicide, with rates of suicide attempts 6–10 greater than the general population. Twin studies have suggested that genetic factors may play a role in suicidal behavior, as they do in alcohol dependence. As part of the Collaborative Study of the Genetics of Alcoholism (COGA), information on suicide attempts and related suicidal behavior was collected as part of a semi-structured assessment interview. More than 2200 individuals from 262 multiplex alcoholic families have been ascertained for linkage analyses in COGA. We conducted affecting sibling pair analyses on the dichotomous phenotype ‘ever tried suicide’ and on a quantitative index of suicidal behavior. This index was formed by totaling positive responses to the following items: Have you ever thought about killing yourself? Did those thoughts persist for at least 7 days

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in a row? Did you have a plan? Have you ever tried to kill yourself? Have you tried multiple times? There was no overlap in findings for the dichotomous phenotype of trying suicide and the quantitative suicidality index. For ‘ever tried suicide’, chromosome 2 yielded a lod score of 4.2 near the marker D2S1790. These findings are in the same chromosomal location as linkage findings previously reported for alcoholism in the COGA sample. For the quantitative suicidality index, regions of chromosomes 1 and 3 yielded lod scores >1.5. The maximum lod score on chromosome 3 was 1.8 near the marker D3S2398. On chromosome 1, the maximum lod score of 1.5 was observed near the marker D1S1602. This is not in the same chromosomal region previously reported linked to alcoholism in the COGA sample. These results suggest that different genes may be involved in suicidal ideation versus actual suicide attempts. We are in the process of further exploring the linkage of both alcoholism and suicide attempts on chromosome 2.

O15 GENOME SCAN OF ALCOHOLISM IN MULTIPLEX BRITISH FAMILIES SUPPORTS THE PRESENCE OF SUSCEPTIBILITY LOCI ON CHROMOSOME 1P AND 1Q Guerrini I,1 Cook CCH,3 Kest W,1 Devitgh A,1 McQuillin A,1 Curtis D,2 and Gurling HMD1 1 Molecular Psychiatry Laboratory, Windeyer Institute for Medical Science, Department of Psychiatry and Behavioural Sciences, Royal Free and University College London, UK 2 Joint Academic Department of Psychological Medicine, St Bartholomew’s and Royal London School of Medicine and Dentistry, UK 3 Kent Institute of Medicine and Health Science, University of Kent at Canterbury, UK Previous genome-wide scan studies have reported suggestive evidences of linkage to alcoholism on chromosome 11p, near the tyrosine hydroxylase and the DRD4 loci, on chromosome 4, in two loci, near the locus for the b 1-GABA receptor unit and near the ADH gene cluster [Long JC, et al., 1998: Am J Med Genet 81:216–221] and also on chromosomes 1p, 2q, 4p, 7q and 16p [Reich T et al., 1998: Am J Med Genet 81: 207–215; Foroud T et al., 2000: Alcohol Clin Exp Res, 24(7):933–945]. We carried out a genome scan on 18 British families, densely affected by alcoholism, by using a set of polymorphic microsatellite markers at loci spanning the genome at 10 cM intervals. Linkage analysis was performed out using ‘‘model-free’’ and a ‘‘model based’’ lod scores methodologies. Analyses were conducted using three different definitions of affection status: Heavy Drinking (HD) according to Royal Psychiatrists Society safety limits, Research Diagnostic Criteria (RDC) alcoholism and Alcohol Dependence Syndrome (ADS) (Edwards & Gross, 1976). Linkage analyses with two point and multipoint analyses

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have shown positive lod scores on chromosome 1p at D1S1588 (MLOD: 1.8), D1S3723 (MLOD: 1.1), D1S532 (MLOD: 1.2), D1S1675 (MLOD: 1.2) for the RDC affection status and at the locus D1S1653 on 1q (MLOD: 1.8) for Heavy Drinking. These results are supportive of linkage in a region on chromosome 1p previously implicated by the USA COGA study and a new possible susceptibility locus on 1q.

O16 ASSOCIATION/LINKAGE DISEQUILIBRIUMS STUDIES IN SUBSTANCE DEPENDENCE Schwab SG,1 Franke P,2 Samochowiec J,3 Trixler M,4 Lichtermann D,2 Guttenthaler V,1 Maier W,2 Kidd KK,5 Osier MV,5 Knapp M,6 Hallmayer J,7 and Wildenauer DB1 1 Molecular Genetics Laboratory, Dept. of Psychiatry, University of Bonn, Germany 2 Dept. of Psychiatry, University of Bonn, Germany 3 Dept. of Psychiatry, Pomeranian Medical University, Sczecin, Poland 4 Dept. of Psychiatry, University Medical School, Pecs, Hungary 5 Dept. of Genetics, Yale University School of Medicine, New Haven 6 Institute for Medical Biometry, Informatics and Epidemiology, University of Bonn, Germany 7 Dept. of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Palo Alto, California There is substantial evidence that genetic factors contribute to the etiology of substance dependence. However, the identification of the underlying genetic pathways is complicated by the complexity of the disorder. In contrast to linkage studies association studies might be able to pick up the smaller effects expected in complex diseases. One of the major problems in genetic association studies is the stratification of the population. A possibility to avoid this problem may be the use of affected children/parent samples (trios). We are focusing in our studies on alcoholism and nicotine dependence. For alcoholism, 192 families with 600 individuals are available for genotyping, two of the families including affected sibpairs. For nicotine dependence 96 families with 317 individuals have been collected, 16 of the families having two affected siblings, 5 families having three affected siblings, and one family having four affected siblings. For 131 families of the alcoholism sample and all families of the nicotine dependence sample, four polymorphisms of the DRD2 gene (DRD2-TaqB, DRD2-TaqD, DRD2-CA and DRD2TaqA) have been typed. TDT analysis did not reveal any positive p-values, neither for single genotypes nor for haplotypes. Current analysis using all samples covers NMDA receptor 2B polymorphism on chromosome 12 and polymorphisms within the ADH gene cluster on chromosome 4.

O17 FUNCTIONAL VARIATION IN PROMOTER REGION OF MAO-A GENE AND SUBTYPES OF ALCOHOLISM: HAPLOTYPE ANALYSIS Parsian A,1 Cloninger CR,2 Sinha R,1 and Zhang ZH3 1 Department of Molecular and Cellular Biology, University of Louisville, Louisville, Kentucky 2 Department of Psychiatry, Washington University, St. Louis 3 National Institute of Health, Bethesda, Maryland Monoamine oxidase A (MAO-A) is a mitochondrial enzyme, which preferentially degrades serotonin and norepinephrine. Sabol et al. (1998) identified a functional 30 base pair repeat polymorphism in the promoter region of the MAO-A gene. This variation affects the transcriptional efficiency of the gene and the 3-repeat allele has lower efficiency than larger alleles in the luciferase expression system. Based on the role of MAO-A gene in serotonergic pathway, this functional variation is an excellent marker for association studies with psychiatric disorders including alcoholism. To determine the role of this functional variation in the development of alcoholism subtypes, a sample of alcoholics (N ¼ 126) and normal controls (N ¼ 85) were screened with this marker. In addition, these samples were screened with a functional variation in exon 8 and a variation in exon 14 of the MAO-A gene. Haplotypes were constructed with these three variations in male samples because the phase is known. Comparisons of total alcoholics and type I alcoholics with normal controls for promoter variation were borderline significance. However, the result of the same comparison for type II alcoholics was not significant. The overall frequency of two loci (MAO-A Pro/exon 8) haplotypes was significantly different between alcoholics and normal controls. The overall comparison of three loci (MAO-A Pro/exon8/exon14) haplotype frequencies between alcoholics and normal controls was also significant. Our results indicated the possibility of the involvement of MAO-A gene in the development of alcoholism.

O18 ALCOHOLISM IS ASSOCIATED WITH POLYMORPHISMS IN NMDA RECEPTOR SUBUNITS Wernicke C,1 Samochowiec J,2 Schmidt LG,3 Smolka M,1 and Rommelspacher H1 1 Departments of Clinical Neurobiology and Psychiatry, University Hospital Benjamin Franklin, Free University of Berlin, Germany 2 Department of Psychiatry, Pomeranian Academy of Medicine, Szczecin, Poland 3 Clinic of Psychiatry, University of Mainz, Germany The function of the ionotropic glutamatergic N-methyl-Daspartate receptors is known to be reduced acutely by physiologically relevant concentrations of ethanol. The ethanol sensitivity seems to depend from the composition of the

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heteromeric receptor. Those receptors which contain the NR1a splice variant and the NMDAR2B subunit are known to be the most sensitive to ethanol. After chronic ethanol exposure tolerance develops, and NMDAR function increases, possible by up-regulated NMDAR numbers and/or by altered NMDAR composition. An increased NMDAR function is also seen during withdrawal. In this study we tested, if recently found polymorphisms in the genes of the NMDAR1 (G2108A) and NMDAR2B (C2664T) subunits are associated with ethanol dependence. Genotyping was done using both FRET-probes in a PCR/melting curve analysis and by conventional RFLP analysis. The study included 367 alcohol dependent individuals and 335 control individuals of German origin for the case control study, and 72 trios of Polish origin for the family based study. For NMDAR1, there was a significant difference in the genotype distribution between alcoholic patients and controls (c2 ¼ 7.328, df ¼ 2, P ¼ 0.026). Furthermore, patients with the homozygote mutation had a significantly less ethanol intake than those bearing a G allele (P ¼ 0.048). For NMDAR2B the T allele prevalence was significantly reduced in patients with an early age at onset, in patients with vegetative withdrawal syndrome, and in Cloninger type 2 alcoholics. Furthermore, patients carrying the C-allele showed higher rates in the personality trait subscale of impulsivity compared to those lacking it (P ¼ 0.042). Our family based study revealed a preferred transmission of the C allele by fathers to the affected offspring.

Slide Session 4: Bipolar II O19 POSITIONAL CLONING OF BIPOLAR SUSCEPTIBILITY GENE IN THE DARIER REGION OF CHROMOSOME 12Q23-Q24 Craddock N,1 Glaser B,2 Green E,1 Jacobsen N,2 Elvidge G,1 Kirov G,2 Lendon C,1 O’Donovan M,2 Jones I,1 and Owen M2 1 Molecular Psychiatry Group, Division of Neuroscience, University of Birmingham, UK 2 Neuropsychiatric Genetics Unit, Division of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK We have described two pedigrees (324: max. lod 2.1; 5501: max. lod 3.6) in which Bipolar Disorder segregates with markers in the region of the Darier’s disease gene, ATP2A2, on 12q23-q4.1. We and other groups have reported independent evidence for linkage of markers in the 12q23-q24 region with susceptibility to Bipolar Disorder in pedigrees unselected for Darier’s disease. As is usual in complex disorders, the signals span a broad region of interest— approximately 30 cM from PAH to D12S1639. Haplotype studies using a dense map of microsatellite markers in pedigrees 324 and 5501 have allowed us to refine the most likely location of the Bipolar susceptibility gene—with the size of region of interest defined by the stringency of the

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assumption about phenotype–genotype relationship. The ‘‘narrowest critical region’’ (using genetic information from all affecteds and unaffecteds) is approximately 7 cM whereas the ‘‘core phenotype critical region’’ (using information only from individuals affected by core phenotype) is approximately 20 cM; both regions include ATP2A2. We are using a combination of positional and candidate gene approaches for identification of the pathogenically relevant gene. Using direct mutation/polymorphism analysis of known and predicted genes within this region of interest we have already excluded the coding and known promoter sequences of 42 of these genes and a further 18 are in progress. Evidence supportive of fine localization has been provided by systematic linkage disequilibrium mapping studies using microsatellite and SNP markers across the region in outbred case-control samples. In this presentation, we will provide a progress report of our search. O20 A NOVEL CPG-ASSOCIATED BRAIN-EXPRESSED CANDIDATE GENE FOR CHROMOSOME 18Q LINKED BIPOLAR DISORDER Del-Favero J,1 Goossens D,1 Van Gestel S,1 Claes S,1 De Rijk P,1 Souery D,2 Massat I,2 Mendlewicz J,2 and Van Broeckhoven C1 1 Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Antwerp (UIA), Belgium 2 Department of Psychiatry, Erasme Hospital, University of Brussels (ULB), Belgium Bipolar (BP) disorder is a severe psychiatric condition affecting about 1% of the population. The clinical signs of BP disorder are alternating episodes of depression and mania (BP type I) or hypomania (BP type II). Genetic studies have identified several potential chromosomal loci; of which chromosome 18 is of particular interest. We previously identified 18q21-q22 as a candidate region for bipolar (BP) disorder and constructed a yeast artificial chromosome (YAC) contig map. Here we identified 3 potential CpG islands using CCG/CGG YAC fragmentation. Analysis of available genomic sequences using bioinformatic tools identified an exon of 3639 bp downstream of a CpG island of 1.2 kb containing a putative transcription initiation site. The exon contained an open reading frame coding for 1212 amino acids with significant homology to the SART-2 protein, weaker homology was found with a series of sulfotransferases. Alignment of cDNA sequences of corresponding ESTs and RT-PCR sequencing predicted a transcript of 9.5 kb which was confirmed by Northern blot analysis. The transcript was expressed in different brain areas as well as in multiple other peripheral tissues. We performed an extensive mutation analysis in 113 BP patients. A total of 9 single nucleotide polymorphisms (SNPs) were identified. Five SNPs predicted an amino acid change of which 2 were present in BP patients but not in 163 control individuals.

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O21 FINE-MAPPING THE BIPOLAR AFFECTIVE DISORDER LOCUS ON CHROMOSOME 18Q22: A REPORT FROM THE HALF-WAY POINT McMahon FJ,1 Chen Y,1 Akula N,1 Schulze TG,1 DePaulo JR,2 Badner JA,1 Cox NJ,1 Hennessy K,1 and Nguyen T1 1 University of Chicago, Chicago, Illinois 2 Johns Hopkins University, Baltimore, Maryland Several studies have detected evidence of genetic linkage between bipolar affective disorder (BPAD) and chromosome 18q22. Recently, our analysis of a clinically-selected subset of families has added support for linkage in this region and defined a 5 MB interval containing 10 consecutive microsatellite markers with lodscores >3. Sequencing in this region is still in progress, encompassing a 60-BAC contig with 3 gaps, 5 known, and up to 25 predicted genes. In order to determine the genetic variation that accounts for the linkage evidence, we are performing systematic linkage disequilibrium mapping with SNPs at 25 kb density. So far we have screened over 220 SNPs obtained from public databases, selecting those that have a minor allele frequency >10% in a panel of 20 unrelated Caucasian CEPH founders. Selected SNPs are genotyped in 93 unrelated cases and an additional 93 unrelated Caucasian CEPH founders by single-base extension methods. To date we have completed genotyping and association analysis of 83 SNPs at a median intermarker distance of 63 kb. Linkage disequilibrium analysis between adjacent markers reveals D0 values greater than 0.3 across 53% of the region. The majority of SNPs show no evidence of association with BPAD. Three widely spaced SNPs show evidence of association at the P < 0.05 level. One SNP is associated at the P < 0.01 level, and all of the linkage evidence in this region is contained in those 17 families segregating the associated allele. Nearby, 10 additional SNPs spanning a 50 kb interval were genotyped; 5 of these also show evidence of association at the P < 0.05 level, but none partitions the linkage evidence. These findings may warrant replication testing in other samples. O22 SUGGESTIVE EVIDENCE FOR LINKAGE OF PSYCHOTIC BIPOLAR DISORDER TO 13Q31 AND 22Q12 Potash JB,1 Zandi PP,1,2 Willour VL,1 Lan TH,3 Avramopoulos D,1 Huo Y,1 MacKinnon DF,1 Simpson SG,4 McMahon FJ,5 DePaulo JR, Jr.,1 and McInnis MG1 1 Department of Psychiatry and Behavioral Sciences, The Johns Hopkins School of Medicine, Baltimore 2 Department of Mental Hygiene, The Johns Hopkins Bloomberg School of Public Health, Baltimore 3 Department of Psychiatry, Yu-Li Veterans Hospital, Hualien, Taiwan. 4 Department of Psychiatry, University of Colorado School of Medicine, Denver 5 Department of Psychiatry, University of Chicago, Chicago, Illinois

Linkage studies of bipolar disorder and schizophrenia have found overlapping evidence for susceptibility genes in fourchromosomal regions: 10p12-14, 13q32, 18p11.2, and 22q12-13. We have previously demonstrated familial aggregation of psychotic symptoms in bipolar disorder pedigrees. Here, we use stratified linkage analysis to test the hypothesis that the bipolar disorder pedigrees most enriched for psychotic symptoms will show increased evidence of linkage to the regions of prior bipolar disorder/schizophrenia linkage overlap. Non-parametric linkage analyses using GENEHUNTER and ASPEX were performed on 65 bipolar disorder families. Ten families were defined as psychotic and 55 families as ‘other’. Two stages of genotyping were performed. GENEFINDER was employed to localize the findings. In initial analyses, the psychotic families showed suggestive evidence for linkage to 13q31 (NPL ¼ 3.33, P ¼ 0.0046) and to 22q12 (NPL ¼ 2.81, P ¼ 0.01). There was no linkage evidence to 10p12-14 or 18p11.2 in the psychotic families or to any of the regions in the other families. Followup genotyping in the psychotic families strengthened the results slightly on 13q31 (NPL ¼ 3.56, P ¼ 0.0031) and on 22q12 (NPL ¼ 3.32, P ¼ 0.005). Analyses using the ASPEX SIBIBD program were also consistent with linkage to 13q31 (LOD ¼ 2.52, P ¼ 0.0006) and 22q12 (LOD ¼ 3.06, P ¼ 0.00009) in the psychotic families. The GENEFINDER 95% confidence interval on 22q12 spanned 4.3 cM or 1.6 Mb and covered the region of the strongest prior findings. These data suggest that psychotic bipolar disorder may be a genetically meaningful subtype. Replication should be attempted in similar families and in schizophrenia families enriched for mood symptoms as these overlap phenotypes may be most closely related to the putative susceptibility genes. The localization of the 22q12 finding particularly encourages further study of this region through linkage disequilibrium and mutational analysis.

O23 CANDIDATE GENE ANALYSIS OF A BIPOLAR AFFECTIVE DISORDER SUSCEPTIBILITY LOCUS ON CHROMOSOME 4q35 Schofield PR,1 Blair IP,1 Badenhop RF,1,2 Adams LJ,1 Scimone A,1 Ewen-White K,3 Donald JA,4 and Mitchell PB2 1 Garvan Institute of Medical Research, Sydney, Australia 2 School of Psychiatry, University of New South Wales and Mood Disorders Unit, Prince Henry Hospital, Sydney, Australia 3 Australian Genome Research Facility, Melbourne, Australia 4 School of Biological Sciences, Macquarie University, Sydney, Australia Previous genome screens on 479 members of our cohort of bipolar disorder pedigrees have identified potential susceptibility loci on chromosome 4q35 [Am J Hum Genet 62: 1084, 1998], 13q14 [Mol Psych 6: 396, 2001], 3q25-26, 9q31-q33 and 19q12-q13 [Mol Psych, in press]. Analysis of

Abstracts

674 individuals, 214 affecteds from 55 pedigrees strengthened evidence for linkage to 4q35, with a maximum twopoint LOD score of 3.2 for marker D4S1652. Haplotype analysis was carried out the 16 pedigrees that showed evidence of linkage using pedigree-specific, identical-bydescent, allele-sharing in order to define a probable disease region. This indicated that the percentage sharing of alleles, identical-by-descent, in affecteds of all linked pedigrees increases from 60% at the centromeric markers to 75% for markers at the telomere. Maximal allele sharing occurred between markers D4S3051 and 4qTEL13 with this 24 cM region defining a most probable disease region. We have constructed a physical and a transcript map of the 4q35 interval. The probable disease region corresponds to 5.5 Mb and the most probable region to 2.3 Mb. The locus is very gene poor, with a high incidence of pseudogenes, redundant and novel repetitive elements. Each of the 11 known and 11 unknown genes and transcripts are being examined for SNP variations in the linked pedigrees by direct sequence analysis of all exons. Using a case-control, phase-known analysis of association we are assessing the possible role of each SNP and SNP haplotype in contributing to bipolar susceptibility. To date, we have excluded significant association based on the discovery of 26 informative SNPs in the exons of 8 known genes.

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because consistent evidence for linkage disequilibrium was difficult to detect even with adjacent markers expected to show disequilibrium. Cases who inherited the D21S171 marker alleles that were associated with bipolar disorder were selected for direct genomic PCR based bi-directional sequencing of the TRPC7 calcium channel gene on LiCor fluorescent sequencers. Several polymorphic single nucleotide base pair variants within the gene have been detected and their significance in relation to the genetic susceptibility to bipolar disorder is currently being assessed [Gurling H, 1998: Chromosome 21 Workshop. Psychiatr Genet 8:109–113; Smyth C, et al., 1997: Genomics 39:271–278]. The research was funded by Medical Research Council grant G9623693N and by a research lectureship from the Priory Hospital, London to Dr. J. Lawrence and by the Neuroscience Research Charitable Trust. We would also like to acknowledge the help of Hamish Scott and Stylianos Antonarakis for providing unpublished mapping information and primer sequences.

Slide Session 5: Statistical Genetics O25 METHODS FOR TESTING IMPRINTING USING AFFECTED SIBLING PAIRS Holmans P MRC Biostatistics Unit, Cambridge, UK

O24 POSITIVE ALLELIC ASSOCIATION OF THE MARKER D21S171 WITH BIPOLAR DISORDER IDENTIFIES TRPC7, A CALCIUM CHANNEL PROTEIN ON CHROMOSOME 21 AT 21Q22.3, AS BEING A CANDIDATE GENE FOR INCREASING SUSCEPTIBILITY TO BIPOLAR AND RELATED UNIPOLAR AFFECTIVE DISORDERS McQuillin A,1 Kalsi G,1 Lawrence J,1 Smyth C,1 Curtis D,2 Bass N,1 and Gurling HMD1 1 Molecular Psychiatry Laboratory, Department of Psychiatry, Royal Free and University College London Medical School, UK 2 Department of Psychological Medicine, St Bartholomew’s and Royal London School of Medicine and Dentistry, UK Linkage analysis of bipolar families from many independent investigators have identified the distal end of the long arm of chromosome 21 as a potential source of genetic susceptibility for bipolar affective disorders. We genotyped 22 genetic markers near the telomere of chromosome 21 at 21q22.3 in 300 cases and 300 ethnically matched controls and found only one marker that gave significant evidence for allelic association with bipolar disorder after a Monte Carlo correction for multiple alleles. Flanking markers gave weaker evidence for allelic association and were only significant without correction for multiple alleles. We found evidence for a very high rate of recombination in this telomeric region

Imprinting (or parent-of-origin effect) occurs when the expression of a gene is dependent on whether it is transmitted by the father or the mother, and has been suggested to play a part in many complex psychiatric traits. It is thus important to allow for imprinting in linkage analyses in an efficient manner, while minimising the chance of obtaining false positives when there is no parent of origin effect. In an affected sib-pair study, imprinting will manifest itself by increasing the probability of an affected pair sharing either their paternal or maternal allele IBD. A number of methods exist to test for such a difference. Firstly, one can count the number of times affected sib pairs share an allele IBD from heterozygous parents, and test for differences in paternal and maternal sharing via a Pearson chi-squared test. Secondly, the contributions of paternal and maternal IBD to the MLS statistic may be assessed by setting each in turn and thereby obtaining lod scores based on the sharing from the other parent. Both of these methods are implemented in ASPEX. A third possibility is to maximise the likelihood with respect to paternal and maternal IBD probabilities separately and compared to the likelihood obtained assuming them to be equal. The performance of these methods both to detect imprinting and linkage allowing for imprinting will be investigated by simulation under a number of different disease models, and illustrated by applying them to the Schizophrenia Collaborative Linkage Group data.

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O26 MULTIFACTOR DIMENSIONALITY REDUCTION IS AN IDEAL DISCRIMINATOR OF DISCRETE CLINICAL ENDPOINTS USING MULTILOCUS GENOTYPES Moore J Vanderbilt University Medical School, Program in Human Genetics, Nashville, Tennessee The identification and characterization of genes whose effects are primarily through interactions with other genes and environmental factors remains a statistical and computational challenge in the genetic epidemiology of common complex multifactorial diseases such as unipolar depression and schizophrenia. We have previously developed a multifactor dimensionality reduction (MDR) approach to identifying gene-gene and gene-environment interactions in case-control and discordant sib-pair study designs. MDR is nonparametric in that no parameters are estimated and is genetic-model free in that no particular genetic model is assumed. Using both simulated and real data, we have previously demonstrated that MDR has excellent power for identifying high-order gene-gene interactions in the absence of any detectable independent main effects of each gene. In the present study, we outline a mathematical proof that MDR ideally discriminates between discrete clinical endpoints using multilocus genotypes. In this proof, we first define the context of the problem, the MDR decision rule, and the error evaluation on which the decision rule is optimized. We then prove that the MDR decision rule is optimal for the given error evaluation. This proof suggests that no analytical approach will classify discrete clinical endpoints using multilocus genotypes better than MDR. Based on this proof, we propose that MDR should be the ‘gold standard’ with which other methods for identifying gene-gene and geneenvironment interactions are compared. O27 COVARIATES IN LINKAGE ANALYSIS Rice J,1 Saccone NL,1 Neuman R,1 Rochberg N,1 Goate A,1 Foroud T,2 Edenberg H,2 and Reich T1 1 Washington University, St. Louis, Missouri 2 Indiana University, Indianapolis, Indianadiana Linkage analysis and association studies are two basic strategies currently used to detect and map susceptibility genes for complex traits. Recent linkage methods have relied on haplotype sharing within affected sib pairs (or sets of affected relatives). These ‘model-free’ methods have several limitations: (a) How to deal with multiple phenotypic definitions such as mild, severe and unaffected? (b) How to combine multiple data sets in a meta-analysis? and (c) How to perform conditional analysis in which sharing at one chromosomal location or association with an allele at a particular locus influences sharing at another location? We address these limitations using a method in which the probability that a sib pair shares an allele from a particular parent is modeled by

logistic regression on a set of covariates. In this setting, covariates may include indicator variables for diagnoses, indicators for the source of data in a meta-analysis, or genotypes at a particular locus. This formulation permits an overall test of linkage as well as individual tests of phenotypic and study heterogeneity. The use of multi-point data allows the estimation of gene location. We apply this to linkage data from COGA (Collaborative Study on the Genetics of Alcoholism). We code an ordinal, hierarchical diagnosis using ICD-10, DSM-IV, DSM-III-R alcohol dependence and unaffected. This generalizes approaches that use only affected sib pairs under one diagnostic definition. Preliminary results indicate replication of linkage signals on chromosomes 1 and 2 using both waves of COGA data. In addition, other findings were noted which were not identified in the prior traditional analyses. O28 SCHIZOPHRENIA, BIPOLAR DISORDER AND CHROMOSOME 1 LINKAGE Macgregor S, Visscher P, Knott S, Thompson P, Millar K, Porteous D, Muir W and Blackwood D University of Edinburgh, UK Of the regions with strong evidence for linkage to psychiatric disease, chromosome 1q is one of the most significant with 2 LODs of greater than 6. We report here another significant linkage result on chromosome 1, in Scottish families (without the 1; 11 translocations) affected by Schizophrenia and affective disorders. Interesting, much of the linkage derives from families mainly affected by bipolar disorder (parametric LOD 3.5 for bipolar families, HLOD 2.8 for all families) and the LOD peak is at 1q42/DISC1. In addition to parametric analyses, robust VC linkage analyses confirmed these results. A recent paper in Science (Levinson et al., 2002) has failed to find appreciable evidence for linkage in a combined analysis of families from several populations. However, in pooling a very diverse sample of families for linkage analyses one relies upon the assumption that the same effects will apply in all the families studied. This assumption is looking increasingly untenable because, despite the large numbers of chromosomal regions with positive linkage results, there are a small number of chromosomal regions which now have substantial evidence for genetic linkage. Large meta-analyses may have good power to detect loci which contribute to susceptibility equally across populations but the presence of even moderate heterogeneity will reduce power to very low levels. However, collecting large numbers of unrelated sib pairs will maximize the extent of heterogeneity found. Simulations using SLINK show that whilst large samples may have sufficient power when the proportion of linked families is high, say 75%, if the the proportion is lower, say 33%, the power is drastically reduced, even if heterogeneity is allowed for in the analyses. In the Scottish population, only a small proportion of families affected by

Abstracts

Schizophrenia and/or Bipolar disorder are linked to chromosome 1. However, in such families, there is now considerable evidence for an important disease locus. O29 LARGE-SCALE CANDIDATE GENE ASSOCIATION ANALYSIS IN PSYCHIATRIC DISORDERS Norton N,1 Williams NM,1 Stephens M,1 Williams HJ,1 Spurlock G,1 Preece A,1 Turic D,1 Grierson A,1 Williams J,1 Kirov G,1 Thapar A,1 Plomin R,2 Owen MJ,1 and O’Donovan MC1 1 Department of Psychological Medicine, UWCM, Cardiff, UK 2 Institute of Psychiatry, London, UK The increasing belief that most neuropsychiatric disorders arise as a result of small gene effects, combined with improvements in molecular genetic technology and the progress of the Human Genome Project has rejuvenated the candidate gene study. In well designed thorough candidate gene analysis projects, much of the time is invested in identifying polymorphisms, whereas much of the cost is invested in genotyping. We have previously shown that the latter can be markedly reduced by pooled genotyping analysis (Hoogendoorn et al., 2000, Norton et al., 2002). Moreover where a given candidate gene system is implicated in multiple phenotypes, pooled analysis offers the opportunity to improve both the efficiency and the prior probability of candidate gene studies by allowing simultaneous testing of multiple phenotypes because the costs of pooled genotyping are negligable compared with the costs of initially identifying the variants. We present data from the glutamatergic system which is an illustrative example of such a candidate gene system. We have screened for sequence variation the genes encoding NMDA, metabotropic, and AMPA receptors as well as those encoding glutamate transporters. To date, we have identified more than 100 SNPs. We have estimated allele frequencies in DNA pools constructed from subjects with schizophrenia, bipolar disorder, ADHD, dyslexia and from subjects with varied levels of cognitive ability. In this presentation, we summarize the results of such analyses Provisional evidence for association has been obtained between variants in glutamate receptors and ADHD, reading disability, and cognitive ability. O30 CAN LONG-RANGE MICROSATELLITE DATA BE USED TO PREDICT SHORT-RANGE LINKAGE DISEQUILIBRIUM? Schulze TG,1,2,3 Chen Y-S,2 Akula N,2 Hennessy,2 Badner JA,2 McInnis MG,4 DePaulo JR,4 Schumacher J,5 Cichon S,5,6 Propping P,5 Maier W,3 Rietschel M,3,7 No¨then MM,5,6 and McMahon FJ1,2 1 NIMH, Bethesda, Maryland 2 Department of Psychiatry, The University of Chicago, Chicago, Illinois

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Department of Psychiatry, University of Bonn, Germany Department of Psychiatry, Johns Hopkins University, Baltimore, Maryland 5 Institute of Human Genetics, University of Bonn, Germany 6 Department of Medical Genetics, University of Antwerp, Belgium 7 Central Institute of Mental Health, Mannheim, Germany 4

The distribution of linkage disequilibrium (LD) across the genome is highly complex. Little is known about the relationship between long-range and short-range LD in a genomic region. We assessed whether a dense set of microsatellite data could be used to predict short-range LD in family samples. We analyzed inter-marker LD in data derived from chromosomal regions 18q22 and 10q25-26, densely genotyped with microsatellite markers. The pattern of LD was highly heterogeneous within and between both chromosomal regions. On 10q25-26 very little LD was detected. On 18q22, where marker density was higher, many marker pairs were in LD. We modeled the decay of LD over distance in this region. A classical model accounted for most of the relationship between LD and distance (R2 ¼ 63%). We used this model to predict the proportion of markers expected to show useful levels of LD at short distances. This prediction agreed with estimates based on SNP marker genotypes in the region. Both microsatellite and SNP data predict that about 80% of marker pairs would display levels of LD that are useful for association studies at distances of up to 15 kb in this region. These projections also agree with levels of LD directly measured in a 10 Kb set of SNP genotypes generated in a nearby region of finished sequence. Our results suggest that existing sets of microsatellite data, if sufficiently dense, may be used to develop good initial estimates of the density of additional markers needed to screen a region for disease alleles by association analysis.

Slide Session 6: Neurological and Psychiatric Childhood Diseases I O31 PHENOTYPIC CHARACTERISTICS OF SIBLINGS WITH AUTISM AND/OR PERVASIVE DEVELOPMENTAL DISORDER: EVIDENCE FOR HETEROGENEITY Freitag CM1 on behalf of The International Molecular Genetic Study of Autism Consortium2 1 Institute for Medical Biometry, Informatics and Epidemiology, University Hospital Bonn, Germany 2 http://www.well.ox.ac.uk/maestrin/iat.html Autism is characterized by impairments in reciprocal communication and social interaction, and by repetitive and stereotyped patterns of activities and interests. Evidence for a strong underlying genetic predisposition comes from twin and family studies. As the recently reported regions of linkage on chromosomes 2q, 7q, 16 and 17q might be

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indicative of heterogeneity or multifactorial inheritance, we analyzed the phenotypic data of these siblings with respect to these hypotheses 420 siblings with autism or any other pervasive developmental disorder (PDD) from 207 families, 6 countries and 11 sites met ADI-R and ADOS-G criteria for autism or PDD. Verbal and performance IQ scores, and information on language level and history of language delay were obtained. The three ADI dimensions differed in severity by country and site. We found significant familial clustering (adjusted for site and method of sampling) for the ADI nonverbal communication and the ADI repetitive scores as well as for performance and verbal IQ, verbal ability and history of epilepsy. When the ADI subdomain scores and the IQ measures for the affected siblings of male and female probands were compared there was no evidence for the gender effects predicted by the classical multifactorial threshold model. Phenotypic analysis of the 420 siblings with autism and/or PDD suggested several domains potentially indexing etiological heterogeneity, pointing to the potential benefits of analysis of possibly more homogeneous subgroups of families. O32 CHROMOSOMAL ANOMALIES IN 4 CHILDREN WITH AUTISM: BREAKPOINTS AND 1 GENE Castermans D, Devriendt K, Wilquet V, Steyaert J, Fryns J-P, and van de Ven W Centre for Human Genetics, University Hospital of Leuven, Belgium Infrequently, neuropsychiatric disorders like autism are associated with chromosomal anomalies. These rare cases may give information on the genetics of the disorder associated with them. We report on the clinical, cytological and molecular findings in 4 patients with autism in whom 4 different chromosomal anomalies were found: one inversion and 3 translocations: Patient1: t (5; 13) (q11.2; q14.11), Patient2: t (1; 15) (p36.11; q24.1), Patient3: inv (10) (centromere; q21.3), Patient4: t (14; 16) (q12; telomere). Two of the children have intelligence in the normal range, and two have a mental retardation. In patient1, a gene located at a breakpoint could be identified. To our knowledge, this gene has not yet been described in association with autism. The finding may be important in research on the genetics of autism. We will illustrate what is known about the function of this gene. O33 A GENETIC ANALYSIS OF THE ASSOCIATION BETWEEN HYPERACTIVITY AND LOW IQ Kuntsi J,1 Eley T,1 Taylor A,1 Hughes C,2 Caspi A,1 and Moffitt T1 1 Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, UK 2 Centre for Family Research, University of Cambridge, UK

Attention deficit hyperactivity disorder and the continuous dimension of hyperactivity are negatively associated with IQ. We present data from 1, 116 twin pairs at age 5 that test the genetic versus environmental mediation of this association. Univariate model-fitting analyses indicate a heritability of 72% for hyperactivity and 40% for IQ. Genetic correlation, which indicates the extent to which the genetic influences on hyperactivity overlap with those on IQ, is estimated at .45. The bivariate model-fitting analyses further indicate that genetic factors account for over 80% of the phenotypic correlation of .3 between hyperactivity and IQ. The shared genetic etiology may indicate pleiotropic effects of genes on hyperactivity and IQ, or genetic causality from one phenotype to the other. O34 DOPAMINE TRANSPORTER GENE AND BEHAVIORAL RESPONSE TO METHYLPHENIDATE (MPH) IN CHILDREN WITH ATTENTION DEFICIT HYPERACTIVITY DISORDER (ADHD) Ben Amor L, Grizenko N, Mbekou V, Lageix P, Baron C, Schwartz G, Ter Stepaninan M and Joober R. Department of Psychiatry McGill University, Douglas Hospital Research Centre, Montreal, Canada. One third of children with ADHD have poor or no response to MPH, the most commonly used treatment. Among genetic factors that may be implicated in modulating response to MPH, dopamine transporter gene (SLC6A3) is a suitable candidate since it has been shown to be the target of stimulants. Aim: to investigate the relationship between SLC6A3 30 end VNTR polymorphism and behavioral/therapeutic response to MPH in children with ADHD (DSM-IV). Method: 42 boys (mean age ¼ 9.2  1.8) were included in a 2-week, double-blind, placebo-controlled crossover trial of MPH (0.5 mg/kg/day). Acute behavioral changes in attention and motor activity were measured using the Conners’ Continuous Performance Test Overall Index (CPT-OI) and the Restricted Academic Situation Scale (RASS) before and 45 min after administration of either placebo or MPH. Ecological therapeutic changes were assessed using the Conners’ global index scale (CGI) parent and teacher reports. Results: For CGI parent, ANOVA between genotypes (10/10, n ¼ 21 vs. 9/10 and 9/9, n ¼ 21) within repeated measure of therapeutic response (MPH-placebo), revealed a significant treatment effect (F1, 40 ¼ 6.53; P ¼ 0.01), no genotype effect (F1, 39 < 1; P ¼ 0.51), and no interaction (F 1, 40 < 1, P ¼ 0.41). For CGI-teacher, there was a highly significant treatment effect (F1, 38 ¼ 24.4, p < 0.001) no genotype effect (F 1, 37 ¼ 2.13, P ¼ 0.15) and a significant interaction between genotype and therapeutic response (F1, 38 ¼ 5.3, P ¼ 0.02). Patients with the 10/10 genotype have a poorer response to MPH. Strong treatment effects were observed on acute behavioral responses (CPT-OI and RASS) but no genotype or interactions

Abstracts

effects. Conclusion: Although preliminary, these results suggest that the SLC6A3 3’VNTR may modulate therapeutic response to MPH as evaluated by teachers. O35 FOXP2, THE GENE ASSOCIATED WITH SPCH1: NOVEL EXONS, SPLICE VARIANTS, AND CAG REPEAT LENGTH STABILITY Bruce HE,1 and *Margolis RL1,2 1 Laboratory of Genetic Neurobiology, Division of Neurobiology, Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, Maryland 2 Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland FOXP2 is a transcription factor containing a polyglutamine tract, a zinc finger motif, and a forkhead DNA binding domain. The FOXP2 gene is located on 7q31. A missense mutation in the forkhead domain (exon 14) and a balanced reciprocal translocation t (5; 7) (q22; q31.2) with a breakpoint between exons 3b and 4 have recently been associated with the speech and language disorder SPCH1. The role of FOXP2 in this neurodevelopmental disorder, and linkage of autism and language disorders to a similar region of 7q, suggest that mutations in FOXP2 could cause other neuropsychiatric disorders. To facilitate investigation of this possibility, we examined the genomic structure and CAG/CAA repeat region of FOXP2. We detected little polymorphism and no expansions in the FOXP2 CAG/CAA repeat in 142 individuals with progressive movement disorders. Using a combination of cDNA library screening, RT-PCR, and sequence analysis of the human genome, we found evidence of alternate splice variants and seven previously undetected exons: three 50 untranslated exons (s1, s2, s3), two additional untranslated exons (2a and 2b) between exons 2 and 3, a translated exon (4a) between exons 4 and 5, and a longer version of exon 10 (10 þ) that contains an alternate stop codon and produces a truncated protein. Our results suggest that FOXP2 spans at least 603 kb of genomic DNA, more than twice the previously defined region, and provide evidence of a previously unknown promoter region flanking exon s1. This demonstration of additional FOXP2 exons and splice variants should facilitate understanding of FOXP2 function and the search for additional FOXP2 mutations. O36 LINKAGE DISEQUILIBRIUM MAPPING PROVIDES FURTHER EVIDENCE FOR A GENE FOR READING DISABILITY ON CHROMOSOME 6P21.3-22 Williams J,1 Turic D,1 Robinson L,1 Duke M,1 Morris DW,1 Webb V,1 Hamshere M,1 Grierson A,1 Williams N,1 Van Den Bree M,1 Chowdhury R,2 McGuffin P,3 Stevenson J,4 Krawczak M,1,5 Owen M J,1 and O’Donovan MC1 1 Dept. of Psych Med, UWCM, Cardiff, UK.

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Dept. of Neuroscience and Cognitive Development, Babraham Institute, Cambridge, UK 3 Social, Genetic and Developmental Psychiatry, IOP, London, UK. 4 Centre for Research into Psychological Development, University of Southampton, UK. 5 Department of Medical Genetics, UWCM, Cardiff, UK Linkage disequilibrium (LD) mapping was used to follow up reports of linkage between reading disability (RD) and a 18 cM region of chromosome 6p21.3-22. Using a two-stage approach, we tested for association between RD and 21 microsatellite markers in two independent samples of 101 (Stage 1) and 77 (Stage 2) parent/proband trios in which RD was rigorously defined. The most significant replicated associations were observed between combinations of markers D6S109/422/1665 (Stage 1 P ¼ 0.002, (adjusted for multiple testing); Stage 2 P ¼ 0.0001) and D6S506/1029/1660 (Stage 1 P ¼ 0.02 (adjusted), Stage 2 P ¼ 0.0001). The only two-marker association observed in both samples was with D6S422/1665 (P ¼ 0.01; P ¼ 0.04). No single marker showed replicated association but D6S506 produced values of P ¼ 0.01 & 0.08 which were significant when combined (P ¼ 0.02). We observed weaker and less consistent evidence of association in a region of confirmed linkage to RD in previous studies. The most consistently significant haplotypic association D6S109/422/1665, showed association with single-word reading, spelling, phonological awareness, phonological decoding, orthographic accuracy and random automated naming, but not with vocabulary or Attention Deficit Hyperactivity Disorder. Our findings strongly support the presence of a gene contributing to RD in a region of chromosome 6 between markers D6S109 and D6S1260, but do not rule out and the presence of a gene between D6S1556 and MOG.

Slide Session 7: Candidate Genes I O37 ASSOCIATION AND LINKAGE STUDIES OF SEROTONERGIC POLYMORPHISMS IN BIPOLAR I DISORDER USING FAMILIAL AND UNRELATED CONTROLS Mansour H, Ranade S, Brar LK, Chowdari KV, Wood J, Devlin B, Kupfer DJ and Nimgaonkar VL Departments of Psychiatry and Human Genetics, University of Pittsburgh School of Medicine, Western Psychiatric Institute and Clinic, Pittsburgh, Pennsylvania The genetic factors contributing susceptibility to Bipolar Disorder I (BD I) are unclear. The mode of inheritance of BD I is complex and individual genetic susceptibility factors may contribute only a fraction of the liability. Therefore, we are presently conducting association studies using candidate gene polymorphisms. Since association studies are critically dependent on the choice of controls, we have employed

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unrelated as well as family based controls. We report on 93 nuclear families having a proband with BD I (DSM IV criteria), as well as available parents. Cord blood samples from local live births served as unrelated, unscreened controls (n ¼ 90). To enable haplotype-based analyses, nine polymorphisms were analyzed at the serotonin 2A receptor gene (5 SNPs for 5-HT2A, and 4 flanking polymorphisms), and two polymorphisms for serotonin transporter (SLC6A4) loci. The HT2A markers included single nucleotide polymorphisms (SNPs), while the SLC6A4 markers included an insertion/deletion polymorphism in the promoter sequence and variable number or tandem repeat polymorphism (VNTR) in the second intron. Associations with both genes have been suggested previously. TDT analyses revealed significant linkage and associations with 74C/A. [ codon 25 Thr/Asn ] (P ¼ 0.02, 1 df) and 1354C/T. [ codon 452 His/Tyr ] (P ¼ 0.008, 1 df), as well as haplotypes bearing these polymorphisms. Significant case-control differences for selected estimated haplotypes were also present. Our results support a plausible association of BD I with 5-HT2A. Analyses employing larger samples are warranted. O38 PHOSPHOLIPASE A2 GENE AND UNIPOLAR AFFECTIVE DISORDER: A MULTICENTRE GENETIC ASSOCIATION STUDY Papadimitriou GN,1,2 Dikeos DG,1,2 Souery D,3 Massat I,3 Del-Favero J,4 Serretti A,5 Rietschel M,6 Oruc L,7 Kaneva R,8 No¨then M,9 Van Broeckhoven C,4 Stefanis CN2 and Mendlewicz J3 1 Athens University Medical School, Department of Psychiatry, Greece 2 University Mental Health Research Institute, Athens, Greece 3 Department of Psychiatry, Free University of Brussels, Belgium 4 Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology, University of Antwerpen, Belgium 5 Vita-Salute University, Department of Psychiatry, San Raffaele Institute, Milan, Italy 6 Department of Psychiatry, University of Bonn, Germany 7 Psychiatric Clinic, University of Sarajevo, Bosnia and Herzegovina 8 Medical University, Maternity University Hospital of Obstetrics, Laboratory of Molecular Pathology, Sofia, Bulgaria 9 Department of Medical Genetics, University of Antwerpen, Belgium The observation that bipolar affective disorder co-segregated with Darier’s disease, and the results from linkage and association studies on bipolar patients indicate that the gene of phospholipase A2 (PLA2, on chromosome 12q23-q24.1) may be considered as candidate gene for affective disorders.

The possible genetic association between PLA2 and unipolar (UP) affective disorder was examined on 321 UP patients compared to 604 controls from six countries (Belgium, Bulgaria, Croatia, Germany, Greece, Italy) participating in the European Collaborative Project on Affective Disorders. The frequency of one allele of the investigated marker (allele 7) was higher among UP patients with more than three depressive episodes than among controls (P ¼ 0.036 Bonferroni corrected), after controlling for population group and gender. Genotypic association under the dominant model of genetic transmission was also found (P ¼ 0.018). The results of the present study suggest that structural variations at the PLA2 gene or the chromosomal region around it should be considered as potentially involved in the pathogenesis of unipolar affective disorder. O39 MONOAMINE OXIDASE A AND TRYPTOPHANE HYDROXYLASE GENE POLYMORPHISMS: DO THEY INTERACT TO AFFECT THE RISK FOR BIPOLAR DISORDER? Preisig M,1 Beaud P,2 Buresi C,2 Henry C,4 Leboyer M,3 and Malafosse A2 1 University Department of Adult Psychiatry, Lausanne, Switzerland. 2 Department of Psychiatry, University Hospital of Geneva, Switzerland. 3 Laboratoire de Recherche sur les Personnalite´s et les Conduites Adaptatives, CNRS URA 1957, Hoˆpital Pitie´Salpe´trie`re, Paris, France. 4 Department of psychiatry, University Hospital Bordeaux, France The goal of the paper was to assess the interaction of the MAOA and TPH to affect the risk of bipolar disorder. In France (Paris, Bordeaux) and Switzerland (Lausanne, Geneva), 461 bipolar patients and 394 controls were assessed using the Diagnostic Interview for Genetic Studies. Controls were recruited from orthopedic units of general hospitals as well as from blood donor centers. Genotype assessment included the MAO-A CA repeat coding for the MAOA and the TPH intron 7 A218C polymorphism. Applying a logistic regression model, we tested the independent effect of the two polymorphisms as well as potential interaction between them. In females, but not in males, pooled data from the four sites showed a highly significant deviation of both the MAOA-CA repeat and the TPH allele distribution between cases and controls. Logistic regression revealed a highly significant main effect of each of the two susceptibility genes on the risk of bipolar disorder. Females with two MAOA-CA a6 alleles have a 1.6 times higher risk for bipolar disorder than those without this allele. Similarly, the presence of two TPH A alleles almost doubled the risk of bipolar disorder. However, these models did not reveal an interaction between the two polymorphisms to affect the risk of bipolar disorder

Abstracts

(according to a multiplicative model). Instead, the risk of bipolar disorder increased with increasing number of susceptibility genes, which suggests an additive effect. Females with all four examined susceptibility alleles were at a 6.8 times higher risk to suffer from bipolar disorder as compared to those without such an allele. These findings are compatible with a polygenic model underlying bipolar disorder. O40 FAMILY-BASED AND CASE-CONTROL STUDIES IDENTIFY BDNF AS A RISK LOCUS FOR BIPOLAR DISORDER Sklar P,1,2 Smoller J,1 Freedman M,1 Daly M,2 Tahl A,2 McInnis MG,3 Bennett P,4 Lim Y-M,5 Kirov G,6 Jones I,4 Owen M,6 Rosenbaum J,1 Sachs G,1 Craddock N,4 DePaulo JR,3 and Lander ES2 1 Massachusetts General Hospital, Boston, Massachusetts 2 Whitehead Institute/MIT Center for Genome Research, Cambridge, Massachusetts 3 Johns Hopkins University School of Medicine, Baltimore, Maryland 4 Queen Elizabeth Psychiatric Hospital, University of Birmingham, UK 5 Columbia University, New York, New York 6 University of Wales College of Medicine, Cardiff, UK Previous data has identified an allele of the gene BDNF as a risk factor for bipolar disorder in a sample of 136 probandparent trios. Excess transmission of Val66Met SNP located in the proBDNF protein was detected (T/U, 53/34, P ¼ 0.042). We now report 2 family based replication samples that provide independent confirmation of the association between this SNP and bipolar disorder as well as supportive evidence in a case-control study. The first replication sample consisted of 197 parent-proband trios (NIMH samples). Genotyping of Val66Met reveals replication of the original association between Val66 and bipolar disorder with a T/U ratio of 75/56, P ¼ 0.048. Genotyping in an additional 145 parent-proband trios from the UK demonstrated a trend in the same direction (T/U ¼ 38/32, P ¼ 0.17). In a case-control study of 122 bipolar patients and 122 controls, the Val allele was more frequent as expected (Val allele ¼ 81.4% cases, 77.9% controls). A genomic control analysis of 37 randomly distributed, unlinked markers revealed no systematic stratification between the cases and the controls. A pooled P value of 0.022 for the family-based and case-control replication samples was obtained by calculating the expected mean and variance of the number of risk alleles found in cases given the number of samples analyzed. Under a multiplicative model, the transmission ratio and the odds ratio are estimators of the genotypic relative risk. A pooled value was obtained for all samples of 1.33. In summary, we present data from 600 bipolar probands indicating that the Val66 allele is a risk allele for bipolar disorder. These data are supported by haplotype analyses identifying an undertransmitted

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haplotype uniquely marked by the rare Met66 allele in all patient samples studied that may be protective for bipolar disorder. O41 CIRCADIAN CLOCK RELATED POLYMORPHISMS AND THE SEROTONIN TRANSPORTER PROMOTER IN SEASONAL AFFECTIVE DISORDER AND SEASONALITY Schalling M,1 Johansson C,1 Willeit M,2 Smedh C,3 Ekholm J,4 Paunio T,4 Lichtermann D,5 Praschak-Rieder N,2 Neumeister A,2,6 Nilsson LG,7 Kasper S,2 Peltonen L,4,8 Levitan R,9 Del Favero J,10 Masellis M,9 Basile V,9 Zill P,11 Bondy B,11 Van Broeckhoven C,10 Lam R,12 Adolfsson R,3 and Partonen T13 1 Neurogenetics Unit, Department of Molecular Medicine, Karolinska Institutet and Karolinska Hospital, Stockholm, Sweden. 2 Department of General Psychiatry, Vienna University, Austria. 3 Department of Clinical Sciences, Division of Psychiatry, University of Umea˚, Sweden. 4 Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland. 5 Department of Psychiatry, University of Bonn, Germany. 6 Mood and Anxiety Disorders Program, National Institute of Mental Health, Bethesda, Maryland 7 Department of Psychology, Stockholm University, Sweden 8 Department of Human Genetics, UCLA School of Medicine, Los Angeles, California 9 Department of Psychiatry, University of Toronto, Canada 10 Department of Biochemistry, University of Antwerp, Belgium 11 Department of Neurochemistry, Ludwig Maximilians University, Munich, Germany 12 Department of Psychiatry, University of British Columbia, Vancouver, Canada 13 Department of Mental Health and Alcohol Research, National Public Health Institute, Helsinki, Finland Conflicting results have been reported in previous association studies of the serotonin transporter promoter repeat length polymorphism (5-HTTLPR), seasonal affective disorder (SAD) and seasonality (seasonal variations in mood and behavior). We genotyped 127 new SAD cases and 107 controls for 5-HTTLPR and included a total of 444 patients and 406 controls in a meta-analysis. In addition, 226 individuals selected for unusually high or low seasonality scores from a population based material and 46 patients with non-seasonal depression were analyzed. Seasonality was analyzed both as a qualitative (high vs. low) and as a quantitative trait in individuals with different psychiatric phenotypes. We found no association between 5-HTTLPR and either SAD or seasonality in any of the materials studied. Our results suggest that the short variant of 5-HTTLPR does not have a major effect

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on susceptibility to SAD or high seasonality scores. Disturbed circadian rhythms have been proposed in SAD. We tested for potential association between polymorphisms in circadian clock related genes and SAD, seasonality or diurnal preference (morningness-eveningness tendencies). One hundred and fifty-nine European SAD patients and 159 matched controls were genotyped for polymorphisms in the CLOCK, Period2, Period3 and NPAS2 genes. A significant difference between patients and controls was found for NPAS2 471 Leu/Ser (c2 ¼ 9.90, Bonferroni corrected P ¼ 0.035), and Period3 647 Val/Gly was associated with self-reported morningness-eveningness scores (one-way ANOVA: F ¼ 4.99, Bonferroni corrected P ¼ 0.044), suggesting possible involvement of these polymorphisms in susceptibility to SAD and diurnal preference, respectively. No association with seasonality was found for neither of the polymorphisms studied, nor for NPAS2 471 Leu/Ser when genotyping a second, population-based sample set from 225 individuals selected for high or low degrees of seasonality. Diurnal preference was however connected with both SAD and seasonality in our material, further supporting the hypothesis of a link between circadian rhythms and seasonal depression. O42 THE SEROTONERGIC SYSTEM INFLUENCES INDIVIDUAL’S RESPONSE TO RISPERIDONE Mata I,1,2 Arranz MJ,1 Lai T,1 Mancama D,1 Arrondo J,2 Beperet M,2 Villavicencio R,1 Munro J,1 Osborne S,1 and Kerwin RW1 1 Clinical Neuropharmacology, Institute of Psychiatry, London, UK 2 Fundacion Argibide, Pamplona, Navarra, Spain The serotonergic system has been hypothesized to partially mediate the antipsychotic activity of psychiatric drugs. Therefore, genetic mutations in the serotonergic system may influence the therapeutic role of the serotenergic system. In support of this hypothesis it was found that polymorphisms in serotonin type 2 (5-HT2) receptors and in the serotonin transporter (5-HTT) were associated with response to antipsychotic and antidepressant drugs. The atypical antipsychotic risperidone displays high affinity for the serotonin receptors 5-HT2A and 5-HT2C and its antipsychotic activity may be influenced by polymorphisms described in the serotonergic system. To check this hypothesis, we genotyped several polymorphisms described in the 5-HT2 (102-T/C and His452Tyr), 5-HT2C (Cys23Ser, -759-C/T, -995-G/A, -330GT/-244-CT) and in the serotonin transporter (5-HTT VNTR and LPR) in a sample of 92 patients from Navarra (Northern Spain) treated with risperidone. Preliminary results showed that a combination of these polymorphisms (using logistic regression) results in the correct prediction of response in 88% of the cases (P < 0.001).

Slide Session 8: Neurological and Psychiatric Childhood Diseases II O43 EVIDENCE FOR ALLELIC ASSOCIATION ON CHROMOSOME 3q25-27 IN FAMILIES WITH AUTISM SPECTRUM DISORDERS ORIGINATING FROM A SUBISOLATE OF FINLAND Auranen M,1,2 Varilo T,1,2 Alen R,3 Vanhala R,4 Ayers K,5 Kempas E,1,2 Ylisaukko-oja T,1,2 Sinsheimer JS,5,6 Peltonen L,1,2,6 and Ja¨rvela¨ I1,2,7 1 Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland. 2 Department of Medical Genetics, University of Helsinki, Finland 3 Unit of Child Neurology, Kuopio University Hospital, Finland 4 Unit of Child Neurology, Hospital for Children and Adolescents, Helsinki, Finland 5 Department of Biomathematics, UCLA School of Medicine, Los Angeles 6 Department of Human Genetics, UCLA School of Medicine, Los Angeles 7 Laboratory of Molecular Genetics, Helsinki University Central Hospital, Finland Recent molecular genetic studies on autism and related disorders have supported a multilocus etiology for the disease spectrum. To maximally utilize genetic and environmental homogeneity we have focused our molecular genetic studies to families originating from a subisolate in Central Finland. Genealogical studies enabled the identification of a megapedigree comprising of 12 core families with infantile autism and Asperger syndrome (AS). We analyzed two chromosomal regions on 1q and 3q showing highest lod scores in our genome wide scan, as well as the AUTS1 locus on chromosome 7q (IMGSAC 2001). With markers on 3q25-27, more significant association was observed in the families from the subisolate than from whole Finland. On this region the LD interval extended 9 cM in families with autism, and 20 cM in families with autism and AS. For 1q markers an association was also detected over 8 cM region but the level of significance remained the same as in the genome scan. In contrast, no clear evidence for association on AUTS1 locus at 7q was obtained. The wide interval showing LD, in particular on chromosome 3q suggest disease gene localization for autism spectrum of disorders on this region. O44 CANDIDATE GENE ANALYSIS, ASSOCIATION STUDIES AND GENOTYPING AT THE AUTISM SUSCEPTIBILITY LOCUS ON CHROMOSOME 16P Barnby GH1and International Molecular Genetics Study of Autism Consortium (IMGSAC)2 1 The Wellcome Trust Centre for Human Genetics, Oxford University, UK 2 http: //www.well.ox.ac.uk/maestrin/iat.html

Abstracts

Autism is a severe neuropsychiatric disorder with a large genetic component estimated from twin studies. Three genome screens to date have reported linkage to regions on chromosome 16p. The highest of these was a multipoint maximum lod score (MLS) of 2.93 at D16S3102 found by IMGSAC in a sample of 152 affected sib-pairs. Liu et al have reported a multipoint MLS of 1.44 at D16S2619, 3 cM distal and Philippe et al generated a multipoint MLS of 0.74 near D16S3075, 6 cM distal. The evidence for an autism susceptibility locus on 16p from these genome screens is sufficient to warrant further investigations in the region. The limited success of fine mapping strategies in narrowing the focus of positional candidate gene studies supports systematic screening of functional candidates within the broad linkage peaks detected. Screening for non-synonymous coding variants also allows identification of synonymous variants and noncoding changes in flanking genomic sequence which can be used in association studies. Affected individuals from the IMGSAC sample were selected for screening based on increased sharing at D16S3102. Coding sequences of candidate genes were screened for mutations using denaturing high performance liquid chromatography (DHPLC) and mutations identified by direct sequencing. An N-methyl-Daspartate receptor (NMDA) gene (GRIN2A), CREB-binding protein (CREBBP), T-box 6 (TBX6), epithelial membrane protein 2 (EMP2), somatostatin receptor 5 (SSTR5) and 4-aminobutyrate aminotransferase (ABAT) have been screened. No strong evidence that these genes contribute to autism susceptibility was found. Twelve single nucleotide polymorphisms (SNPs) detected during candidate gene screening have been typed in the whole IMGSAC sample and analyzed for association. Genotyping of the most recent IMGSAC wave of families has also been carried out on chromosome 16p. O45 FINE MAPPING OF A SUSCEPTIBILITY REGION AND CANDIDATE GENE STUDIES ON CHROMOSOME 2q IN AUTISM Gallagher L,1 Ennis S,2 Kearney G,1 Fitzgerald M,1 Stallings R,2 Barton D,2 Green AJ,2 and Gill M1 1 Department of Psychiatry/Genetics, Trinity College, Dublin, Ireland 2 Conway Institute, University College Dublin, Ireland Autism is a neurodevelopmental disorder of childhood with deficits in the core areas of communication, social interaction and behavior. The role of genetic factors in the etiology is well accepted. Genomewide studies in autism have identified a number of regions of putative linkage. A number of groups have reported evidence for linkage on Ch2q [IMGSAC, 2001; Buxbaum et al., 2001; Shao et al., 2002]. We have described elsewhere a case of autism associated with a deletion on Ch2q lying within the described linkage findings [Gallagher et al., in press]. The deleted region has been

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mapped to an 8.5 Mb region lying within the published linkage findings. Included within this region is marker D2S364 which Buxbaum et al. [2001], reported as showing the strongest evidence for linkage. Sixteen known genes have been identified within the region and five of these were selected initially for the subject of further studies based on their CNS expression. Mutational screening has been completed on the exons of three of these candidates. One of the genes revealed a number of new polymorphisms, which are currently being sequenced. An initial fine mapping experiment of the region in a sample of 80 Irish autistic trios involved 16 polymorphic microsatellite markers has been undertaken. O46 LINKAGE AND ASSOCIATION OF THE GRIK2 (OR GLUR6) GENE WITH AUTISM Jamain S,1 Betancur C,2 Quach H,1 Gillberg C,3,4 Leboyer M,2,5 and Bourgeron T1 1 INSERM E021, Institut Pasteur, Paris, France. 2 INSERM U513, Cre´teil, France. 3 Department of Child and Adolescent Psychiatry, Go¨teborg University, Sweden. 4 Saint George’s Hospital Medical School, London, UK. 5 Hoˆpital Albert Chenevier et Henri Mondor, Assistance Publique-Hoˆpitaux de Paris, Cre´teil, France A genome scan was previously performed and pointed to chromosome 6q21 as a candidate region for autism. This region contains the glutamate receptor ionotropic kainate 2 (GRIK2 or GluR6) gene, a functional candidate for the syndrome. The affected sib-pair (ASP) method, conducted with additional markers on the 51 original families and in 8 new sibling pairs, showed a significant excess of allele sharing, generating an elevated multipoint maximum LOD score (ASPEX MLS ¼ 3.28). The transmission disequilibrium test (TDT), performed with an additional independent data set of 107 parent-offspring trios, indicated a significant maternal transmission disequilibrium (P ¼ 0.0004). Furthermore, TDT analyses (with only one affected proband per family) showed significant association between GRIK2 and autism (TDT association P ¼ 0.008). In contrast to maternal transmission, paternal transmission of GRIK2 alleles was as expected in the absence of linkage, suggesting a maternal effect such as imprinting. However, expression studies of the GRIK2 mRNA in human and rat brain do not provide evidence for unequal allelic expression of the gene in the adult brain. Mutation screening was performed in 33 affected individuals, revealing several nucleotide polymorphisms (SNPs), including one amino acid change (M867I) in a highly conserved domain of the intracytoplasmic C-terminal region of the protein. This change is found in 8% of the autistic subjects and in 4% of the control population and seems to be more maternally transmitted than expected to autistic males (P ¼ 0.007). Taken together, these data suggest that GRIK2 is in linkage disequilibrium with autism.

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O47 GENETIC ANALYSIS OF THE 15q11-q13 AUTISM CANDIDATE REGION PROVIDES CONTINUED SUPPORT FOR A SUSCEPTIBILITY LOCUS Nurmi EL,1 Olson LM,1 Amin T,1 Jacobs MM,1 McCauley JL,1 Dowd M,2 Folstein SE,2 Haines JL,1 and Sutcliffe JS1 1 Program in Human Genetics, Vanderbilt University, Nashville, Tennessee 2 Department of Psychiatry, New England Medical Center, Boston, Massachusetts Autism is a complex genetic disorder characterized by deficits in reciprocal social interaction and language, and repetitive or restricted patterns of behaviors and interests. Models suggest that oligogenic inheritance of an unknown number of susceptibility genes underlies risk for this disorder. Chromosome 15q11-q13 has been suggested as a candidate region, based on maternal chromosomal duplications in a small percentage of autistic individuals. However, results from linkage studies of this region have been mixed. Analysis of linkage to 15q11-q13 in an autism sub-phenotype corresponding to splinter skills reveals significantly increased evidence for linkage, with a maximum recessive HLOD of 2.6 at GABRB3. Maternal-specificity for duplicationassociated risk implies an involvement of maternally-expressed genes in this region. The Angelman syndrome gene, UBE3A, and another maternally-expressed gene, ATP10C, are localized proximal to a cluster of non-imprinted GABAA receptor subunit genes and OCA2. We have analyzed a dense map of single nucleotide polymorphism (SNP) markers throughout the candidate region, to evaluate possible transmission disequilibrium in autism families. We have observed several instances of significant transmission disequilibrium in ATP10C in regions, which display strong evolutionary sequence conservation. These data may represent the direct detection of a functional variant or alternatively the detection of an ancestral haplotype containing a functional susceptibility allele. Case-control analyses, using a CEPH comparison sample, have also revealed significant findings at multiple markers in this region, including the ATP10C gene, adjacent to GABRB3. These data are consistent with the presence of one or more ancestral alleles conferring susceptibility to this complex genetic disorder. O48 THE FIRST GENOME-WIDE SCREEN IN ASPERGER SYNDROME: EVIDENCE FOR LINKAGE ON CHROMOSOME 1q21-22 OVERLAPPING WITH A MAJOR SCHIZOPHRENIA LOCUS Ylisaukko-oja T,1,2 Nieminen-von Wendt T,3 Kempas E,1 Sarenius S,3 Auranen M,1,2 von Wendt L,3 Peltonen L,1,2,4 and Ja¨rvela¨ I1,2,5 1 Department of Molecular Medicine, National Public Health Institute, Helsinki, Finland.

2

Department of Medical Genetics, University of Helsinki, Finland 3 Unit of Child Neurology, Helsinki Hospital for Children and Adolescents, University of Helsinki, Finland. 4 Department of Human Genetics, UCLA School of Medicine, Los Angeles 5 Laboratory of Molecular Genetics, HUCH-Laboratory Diagnostics, Helsinki, Finland Asperger syndrome (AS) is a member of autism spectrum disorders. It is characterized as difficulties in social interaction and communication as well as the presence of circumscribed interests and activities. We have performed a two-stage genome-wide screen with 17 Finnish families, where AS segregated dominantly. All the patients were personally interviewed by one of the authors and the diagnoses were based on ICD-10. In the first stage, nine loci were found to have Zmax >1.5. These were on chromosomes 1q21-22, 3p14-24, 3q25-27, 4p15, 4q32, 6p25, 6q16, 13q3133 and 18p11. In the second stage, these loci were analyzed with the complete family material and a denser set of microsatellite markers. The highest two-point lod score was observed on chromosome 1q21-22 (Zmax ¼ 3.59). Also five flanking markers gave support for linkage on this region (Zmax >1.5). In addition, evidence for a common shared haplotype extending 3.0 cM was observed in three families. Evidence for linkage on 1q21-22 has previously been reported in both schizophrenia and autism. Interestingly, schizophrenia was found as a coexisting diagnosis in three AS-patients and in two family members. These findings rise a question about a common genetic background in AS and schizophrenia. We also found Zmax of 2.52 on chromosome 3p14-24, which is located near the previous findings in autism.

Slide Session 9: Neurological Brain Diseases O49 ASSOCIATIONS BETWEEN ALLELES OF APOLIPOPROTEINE AND MEMORY PERFORMANCE IN NON-DEMENTED INDIVIDUALS Nilsson LG,1 Nyberg L,2 Cruts M,3 Ba¨ckman L,4 Van Broekhoven C3 and Adolfsson R5 1 Department of Psychology, Stockholm University, Sweden 2 Department of Psychology, Umea˚ University, Sweden 3 Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Antwerp (UIA), Belgium 4 Department of Psychology, Uppsala University, Sweden 5 Department of Clinical Sciences, Psychiatry, Umea˚ University, Sweden Associations between alleles e3 and e4 of apolipoprotein E gene and performance on tests assessing episodic memory, semantic memory, primary memory, and priming, in

Abstracts

non-demented individuals were examined. A conservative criterion was used for exclusion of demented persons. Those persons were excluded who were diagnosed as demented up to five years after memory testing took place. Analyses of longitudinal data from two test occasions, five years apart, revealed a significantly lower performance for old carriers of the e4 allele in episodic memory tasks. Young and middleaged subjects did not show this effect. For tasks assessing semantic memory, primary memory, and priming, there were no differences between carriers of the two different alleles in any age cohort. Analyses of change scores in longitudinal data also revealed a dose effect for episodic memory tasks, such that carriers of two e4 alleles performed worse than those with one e4 allele, who in turn performed worse than carriers of non-e4 alleles. This effect was most pronounced in tasks providing cognitive support at both encoding and retrieval, suggesting a deficit in utilizing such support in carriers of the e4 allele. O50 APOE E4 IS A RISK FACTOR FOR DEMENTIA AND PREMATURE DEATH: FINDINGS FROM A LONGITUDINAL STUDY ON PERSONS WITH DOWN’S SYNDROME Gill M, Tyrrell J, McCarron M, Cosgrave M, and Lawlor B Department of Psychiatry, Trinity College Dublin, St Michael’s House, Ballymun, Dublin, Ireland ApoE e4 is a risk factor for dementia and premature death: Findings from a longitudinal study on persons with Down’s syndrome: Individuals with Down’s syndrome are known to have an increased risk for Alzheimer’s disease. This increased risk is felt to be due to three copies of the amyloid precursor protein gene on chromosome 21. In the general population, there is an association between the allele for Apolipoprotein E e4 and Alzheimer’s disease. A cohort of 289 people with Down’s syndrome was followed longitudinally over a four year period. At three years, the prevalence of dementia was 25%. Presence of dementia was associated with increased age, presence of epilepsy and head injury. There were 73 people with dementia. ApoE genotypes were available for 56 people with dementia. 56 people with dementia were compared to 56 age-matched controls without dementia for the presence of the ApoE e4 and ApoE e2 allele. There was no significant difference between the ApoE e2 allele in the demented and non-demented groups 5.67% vs. 10.6% w2 ¼ 1.5, d. f. ¼ 1, P ¼ 0.22, however there was a trend for presence of the e4 allele that was different between demented and non-demented groups 19% vs 8.5% w2 ¼ 3.6, d. f. ¼ 1, p < 0.058. There were 24 deaths in the cohort, compared with age-matched case-controls, the absence of an e2 allele in the group that had died was significant 0% vs. 9.8%, P ¼ 0.026 (Fisher exact) and the presence of the e4 allele deleterious in the dead group 26% vs. 9.3%, w2 ¼ 5.59, d. f. ¼ 1, P ¼ 0.018. Initial studies performed by our group

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demonstrated a protective effect of the ApoE e2 allele in preventing dementia. As the cohort aged however the detrimental effect of the ApoE e4 allele is now evident as a risk factor for death and possibly dementia. At year three the protective effect of the ApoE e2 allele is not shown for dementia but still appears protective against premature death. The effect of increased age in the cohort may be responsible for the different findings between baseline findings and year three results. These findings are in keeping with studies in the general population, but the deleterious effect of ApoE e4 has previously only been shown for people with Down’s syndrome by Schupf et al. [1996] and meta-analysis [Rubinsztein, 1999; Deb, 2000]. O51 IS THE SAITOHIN GENE INVOLVED IN NEURODEGENERATIVE DISEASES? Verpillat P INSERM U535, Departement of Genetic Epidemiology and Structure of Human Population, Le Kremlin Biceˆtre Cedex, France Recently, a single nucleotide polymorphism that results in an amino-acid change (Q7R) was identified in a previously undescribed gene, named saitohin, nested within the tau gene. We characterized this polymorphism in 499 patients with Alzheimer’s disease (AD), 100 patients with frontotemporal dementia (FTD) and 402 controls. We found that this polymorphism could be a risk factor for these two diseases, but above all that it was in complete disequilibrium with the previously well-defined extended tau haplotype. This finding raises the question whether it is the tau gene or the saitohin gene, which is involved in neurodegenerative diseases. O52 HUNTINGTON’S DISEASE-LIKE 2: A NEW NEUROPSYCHIATRIC DISORDER CAUSED BY A CAG/CTG REPEAT EXPANSION IN JUNCTOPHILIN-3 Margolis RL,1,2 Ross CA,1,2,3 Holmes SE,1 O’Hearn E,3,4 Rosenblatt A,1 Callahan C,1 Hwang J,1 Rudnicki D,1 and Troncoso J5 1 Department of Psychiatry, Johns Hopkins University School of Medicine, Baltimore, Maryland 2 Program in Cellular and Molecular Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 3 Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, Maryland 4 Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland 5 Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland We recently reported that a CAG/CTG expansion in a variably spliced exon of Junctophilin-3 on 16q causes a neuropsychiatric disorder, termed Huntington’s disease-like 2

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(HDL2), that is clinically indistinguishable from Huntington’s disease (HD). We have now confirmed the existence of this new disorder in at least seven independent pedigrees. Across all populations so far examined, HDL2 accounts for about 0.5–1% of HD-like cases that test negative for the HD gene, though the frequency of HDL2 is higher if cases are limited to those with an autosomal dominant inheritance and a phenotype typical of HD. Most pedigrees are of African descent. Repeat length is tightly correlated with younger age of onset. Individuals with shorter expanded repeats (about 42–49 triplets) tend to present with prominent chorea, while those with longer expansions (50 or more triplets) tend to have more rigidity and dystonia (similar to juvenile onset HD). Almost all affected individuals have psychiatric symptoms or syndromes. The two brains available for autopsy both show an HD pattern of neurodegeneration and intranuclear inclusion bodies similar to those seen in HD. We are now developing biochemical techniques and cell and animal models to define the pathogenesis of HDL2, with the hope that this will provide insight into HD and other more common forms of neurodegenerative disease. O53 THE LONG-CHAIN FATTY ACID-COA LIGASE 4 (FACL4) GENE IS MUTATED IN FAMILY MRX68 Frints S,1 Fryns JP,2 Borghgraef M,2 Longo I,3 Pescucci C,3 Ariani F,3 Meloni I,3 Marynen P,1 Froyen G,1 and Renieri A3 1 Human Genome Laboratory, Flanders Interuniversity Institute for Biotechnology, University of Leuven, Belgium 2 The Clinical Genetics Unit, University Hospital Leuven, Department of Human Genetics, Belgium 3 Department of Molecular Biology, Medical Genetics, University of Siena, Italy Investigation of patients with mental retardation (MR) as part of a contiguous gene deletion syndrome, combined with linkage data of families with nonspecific X-linked MR (MRX), led to the identification of the FACL4 gene in the Xq23 chromosomal region as a MRX gene [Meloni et al., 2002: Nat. Genet. 30:436-40]. We present family MRX68 with 5 affected men in two generations. The intelligence levels in affected men range from mild to moderate MR. The personality profiles gave poor results on dimensions ‘‘motor activity’’ and ‘‘creativity.’’ One affected autistic child had severe social and thought problems, together with attention deficit disorder. No facial dysmorphism or neurological abnormalities were present. Molecular investigations including multipoint linkage analysis, showed a maximum LODscore of 2.1 at marker COL4A5 with DXS8020 and DXS1220 as flanking markers. X-inactivation studies in women carriers showed a 100% skewed X-chromosome methylation. Mutation analysis of FACL4 revealed a novel segregating missense mutation 1001C > A which was not found in 300 control alleles. Analysis of the arachidonyl-

CoA synthetase activity on patients’ whole cell lysate (EBV cell-lines), demonstrated a marked reduction in activity, similar to the baseline levels seen in patients with a FACL4 deletion. Because FACL4 is expressed as a brain-specific isoform in several brain regions including hippocampus, a role for this gene in cognitive processes is expected. The present finding supports that aberration in fatty acid metabolism in brain can lead to cognitive impairment. The autistic boy in MRX68 shows that there might be an overlap between so-called nonspecific MR and pervasive developmental disorders. O54 IDENTIFICATION OF GENES PREDISPOSING TO IDIOPATHIC GENERALISED EPILEPSY Makoff AJ,1 Asherson P,1 Chioza B,1 Wilkie H,1 and Nashef L2,3 1 Institute of Psychiatry, London, UK 2 Kent & Canterbury Hospital, UK 3 King’s College Hospital, UK Idiopathic generalized epilepsy (IGE) is a common disorder, with a cumulative incidence of 0.7%. It comprises a spectrum of syndromes and more than one syndrome is frequently observed within the same family. The common forms of IGE have a complex pattern of inheritance, thought to be due to the action of several genes of small to moderate effect. Family and twin studies support the concept of some susceptibility genes being shared across IGE syndromes, with the particular syndrome determined by specific genes and/or specific combinations. Association studies involving only a few hundred cases and controls have sufficient power to detect susceptibility genes of small effect, although they are vulnerable to stratification artifacts. Because IGE usually first presents in childhood or early adulthood, parents of the probands are often available, enabling family association studies which are robust to population stratification. We have collected from Kent and Canterbury Hospital over 250 IGE probands, both parents from about half the probands and over 250 controls. We have investigated several candidate genes and have found significant associations with IGE in a Ca channel gene (CACNA1A) and the mu opioid receptor gene (OPRM1). In CACNA1Awe found associations with 5 single nucleotide polymorphisms (SNPs)in a 30 kb region between exons 6 and 9 and have identified a risk haplotype (P ¼ 0.00000014). Haplotype and linkage disequilibrium (LD) analyses have suggested the presence of a functional SNP in this region. In OPRM1 we have found 2 SNPs associated with IGE: one in exon 1 and the other 290 bp upstream in the 50 -UTR, but not in LD with each other. Haplotype analysis identified a protective haplotype (P ¼ 0.000087) and suggested the presence of a functional SNP towards the 50 end of the gene, possibly in the promoter region. Fine mapping studies are currently being performed on both genes in order to identify the functional variants responsible for altered risk of IGE.

Abstracts

Slide Session 10: Candidate Genes II O55 PROTOCADHERINXY AS CANDIDATE GENE FOR CEREBRAL ASYMMETRY AND PSYCHOSIS: IS THE VARIATION EPIGENETIC? Crow TJ,1 Chance SA,1 Giouzeli M,1 Priddle T,1 Williams N,1 and DeLisi LE2 1 Department of Psychiatry, University of Oxford, Warneford Hospital, UK 2 Department of Psychiatry, New York University School of Medicine, New York, New York Recent post-mortem investigations suggest that the focus of change is in the cerebral cortex, that structure which has changed most in man relative to great apes. Two lines of evidence—studies of hand preference and the structure of the planum temporale—support the case that the cerebral torque (a deviation across the fronto-occipital axis) distinguishes the brain of Homo sapiens from that of the chimpanzee. In a post-mortem MRI study we find 2 components of the torque—a hemisphere shift that is not altered in patients with schizophrenia by comparison with controls, and a shift in volume distribution: in controls the mean maximum width was anterior on the left compared to the right and in patients it was anterior on the right (ANOVA for side x dx: P < 0.01). The finding is consistent with other studies indicating that cortical asymmetry is changed in schizophrenia and suggests that the variation relating to psychosis was introduced late in the course of hominid evolution. A candidate gene is protocadherinXY (codes for a cell surface adhesion molecule), located in the Xq21.3/Yp region of homology, created by a translocation (and subsequent paracentric inversion) from Xq to Yp in the course of recent hominid evolution. In immunohistochemical studies, the gene is expressed in pyramidal cells in the human cerebral cortex. The X and Y copies of the gene have been subject to selective pressure that has apparently varied between species, and in one or more hominid species has been subject to sexual selection. We find no sequence variation that is related to psychosis. However, because of the above chromosomal changes this gene is for the first time subject to protection from X chromosome inactivation. There may therefore be significant epigenetic variation that is relevant to inter-individual differences. Such variation may be related to the epigenetic variation that has been shown in twin studies to be associated with anatomical asymmetry and psychosis. O56 POLYMORPHISM SCREENING OF PIP5K2A: A CANDIDATE GENE FOR 10P-LINKED PSYCHIATRIC DISORDERS Stopkova P,1 Saito T,1 Papolos DF,1 Stryjer R,2 Strous RD,2 and Lachman HM1 1 Department of Psychiatry and Behavioral Sciences, Division of Psychiatry Research, Albert Einstein College of Medicine, Bronx, New York

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Beer Yaakov Mental Health Center, Sackler School of Medicine, Tel Aviv University, Israel Lithium is a potent noncompetitive inhibitor of inositol monophosphatases, enzymes involved in phosphoinositide (PI) and inositol phosphate metabolism. A critical component of the PI pathway is phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2), which is hydrolyzed to second messengers and has a direct role in synaptic vesicle function. Interestingly, a number of genes involved in the synthesis and dephosphorylation of PtdIns(4,5)P2 are found in regions of the genome previously mapped in bipolar disorder (BD) including 10p, 21q, and 22q, among others. Some of these regions overlap with loci mapped in schizophrenia (SZ). One gene involved in PI metabolism that maps to a region of interest is 10p-linked PIP5K2A, a phosphatidylinositol 4-phosphate 5-kinase. Polymorphism screening revealed the existence of an imperfect CT repeat polymorphism located near the exon 9-intron 9 splice donor site. A statistical trend was found in the distribution of alleles from this highly polymorphic variant when bipolar and schizophrenic subjects were compared with controls; relatively rare short repeat variants were found more commonly in patients and homozygosity for a common long repeat variant was found in three-fold more controls than patients with BD. These data suggest that the imperfect CT repeat in PIP5K2A intron 9 should be further investigated as a possible candidate allele for 10p-linked psychiatric disorders. O57 ASSOCIATION AND LINKAGE ANALYSES OF RGS4 POLYMORPHISMS IN SCHIZOPHRENIA Chowdari KV,1 Mirnics K,1,2 Semwal P,5 Wood J,1 Lawrence E,3 Bhatia T,6 Deshpande SN,6,7 Thelma BK,5,6 Ferrell RE,3 Middleton FA,2 Devlin,1,3 Levitt P,2 Lewis DA,1,4 and Nimgaonkar VL1,3,6 1 Department of Psychiatry, University of Pittsburgh, Pittsburgh, Pennsylvania 2 Department of Neurobiology, University of Pittsburgh, Pittsburgh, Pennsylvania 3 Department of Human Genetics, University of Pittsburgh, Pittsburgh, Pennsylvania 4 Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania 5 University of Delhi South Campus, New Delhi, India 6 Indo-US Project on Schizophrenia Genetics, New Delhi, India 7 Dr. R. M. L. Hospital, New Delhi, India Gene expression analyses of postmortem cerebral cortex suggest that transcription of the Regulator of G-protein Signaling 4 (RGS4) is decreased in a diagnosis specific manner in subjects with schizophrenia. To evaluate the possible role of RGS4 in the pathogenesis of schizophrenia, we conducted genetic association and linkage studies using samples ascertained independently in Pittsburgh, New Delhi

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and by the NIMH Collaborative Genetics Initiative. Using the TDT, significant transmission distortion was observed in the Pittsburgh and NIMH samples. Among SNPs spanning approximately 300 kb, significant associations involved four SNPs localized to a 10 kb region at RGS4, but the associated haplotypes differed. A trend for transmission distortion was also present in the Indian sample for haplotypes incorporating the same SNPs. Consistent with the linkage/association observed from the family-based tests, samples with affected siblings (NIMH, India) showed higher levels of allele sharing, identical by descent, at RGS4. When the US patients were contrasted to two population-based control samples, however, no significant differences were observed. We also examined US families with Bipolar I Disorder (BD1) probands. This sample showed a trend for transmission distortion and cases differed significantly from the populationbased controls for the four-SNP haplotypes tested in the other samples. The transmission distortion is unlikely to be due to chance. We are presently clarifying its mechanism and specificity. O58 THE HAPLOTYPIC COMBINATION ALLELE1 (IL-1B)/ALLELE2 (IL-1RN) AT THE INTERLEUKIN-1 LOCUS IS ASSOCIATED WITH RISK TO SCHIZOPHRENIA AND BIPOLAR DISORDER Papiol S,1 Martı´n B,1 Rosa A,1 Gutie´rrez B,1 Arias B,1 Salgado P,2 Catala´n R,3 Gasto´ C3 and Fan˜ana´s L1 1 Unitat d’Antropologia, Facultat de Biologia, Universitat de Barcelona, Spain 2 Inst. Municipal de Psiquiatria Urgencies. Barcelona, Spain 3 CAP Salut Mental Esquerra de l’Eixample, Hospital Clı´nic de Barcelona, Spain Over the last decade, altered levels of plasma interleukines have been reported in schizophrenic and bipolar patients. A dual role of cytokines has been described in neurodevelopmental and neurodegenerative processes. Genetic association between schizophrenia and polymorphisms in interleukin-1beta (IL-1B) and interleukin-1Receptor Antagonist (IL-1RN) genes, located in the interleukin-1 gene cluster, has been described in previous studies. However, the role of these polymorphisms in other psychoses remains unknown. For this study, we examined 88 bipolar patients, 78 schizophrenic patients and 176 healthy controls, all of them of Spanish origin. A biallelic polymorphism in the promoter region (-511) of IL-1B and a pentallelic VNTR in intron 2 of IL-1RN were analyzed in all subjects and allelic, genotypic and haplotypic frequencies were calculated for each diagnostic group and controls. A significant excess of allele 1 of IL-1B gene was detected in schizophrenic compared to controls (P ¼ 0.03). The same occurs when the subgroup of bipolar patients showing psychotic symptoms were selected for comparison with controls (P ¼ 0.02). When VNTR of the IL-1RN gene was considered for the analysis, no differences in allelic or genotypic frequencies where

found between cases and controls. However, a significant increase of the haplotypic combination allele1 (IL-1B)/ allele2 (IL-1RN) was detected in both schizophrenic (P ¼ 0.0004, OR ¼ 2.73 (1.48–5.01)) and bipolar patients (P ¼ 0.004, OR ¼ 2.26 (1.23–4.16)) compared to controls. These results suggest that IL-1 locus contributes to susceptibility to schizophrenia and bipolar disorder. Our data are in agreement with hypothesis of the existence of genes of risk shared by both disorders. This study was supported by a grant from Fundacio´ ‘La Caixa.’ O59 ICER PROMOTER POLYMORPHISM—ASSOCIATION STUDY IN EUROPEAN PANIC SAMPLES Domschke K,1 Kuhlenba¨umer G,1 Schirmacher A,1 Lorenzi C,6 Armengol L,7 DiBella D,6 Gratacos M,7 Garritsen H,1 No¨then M,2,5 Franke P,2 Sand P,3 Fritze J,4 Perez G,7 Maier W,2 Beckmann H,3 Sibrowski W,1 Estivill X,7 Bellodi L,6 Ringelstein E,1 Arolt V,1 Martin-Santos R,7 Catalano M,6 Sto¨gbauer F,1 and Deckert J1 1 University of Mu¨nster, Germany 2 University of Bonn, Germany 3 University of Wu¨rzburg, Germany 4 University of Frankfurt, Germany 5 University of Antwerp, Belgium 6 IRCCS H San Raffaele, Milan, Italy 7 CGMM, Hospital del Mar, Barcelona, Spain Mice deficient for the transcription factor cAMP responsive element modulator (CREM) gene, which plays a pivotal role in the HPA axis, are less anxious than their wildtype counterparts. In the present study, we therefore analyzed genetic variation of the CREM gene in panic disorder. We performed a systematic mutation screening of CREM and its alternative product ICER in a sample of 40 German patients by means of SSCA. Allele frequencies were determined in the extended German sample (n ¼ 88) and for the ICER promoter polymorphism subsequently also in independent Italian (n ¼ 76) and Spanish (n ¼ 62) samples using RFLP, direct sequencing and fragment analysis. We identified four SNPs in CREM promoters P1 and P4 and one trinucleotide (ATT)-repeat polymorphism in CREM promoter P2 generating the ICER isoform. Association analysis in the German sample revealed an association of the shorter ICER promoter 8-repeat allele with panic disorder (P ¼.02), in particular with panic disorder without agoraphobia (P ¼.001). Replication studies in Italian and Spanish samples could not confirm the initial finding in the overall samples, only in the Italian male subgroup of patients with panic disorder without agoraphobia a significant association (P ¼.03) was observed. This failure to unequivocally replicate the original German finding argues against a major role for the ICER promoter trinucleotide polymorphism in the pathogenesis of panic disorder. Future studies will have to evaluate its functional relevance and its role in panic and other mental disorders.

Abstracts

O60 TRYPTOPHAN HYDROXYLASE AND MAOA GENES IN SUICIDAL BEHAVIOUR Courtet Ph,1 Buresi C,2 Baud P,2 Astruc B,1 Jollant F,1 Tores S,1 and Malafosse A2 1 Department of Psychiatry, University Hospital of Montpellier, France 2 Department of Psychiatry, University Hospital of Geneva, Switzerland A genetic contribution to suicidal behavior has been demonstrated in family, twin and adoption studies. There is compelling evidence for a specific genetic component of susceptibility, which may be independent of or additive to the genetic transmission of the psychiatric disorders strongly related to suicidal behavior (bipolar disorder, schizophrenia, alcoholism). Since deviations in the serotonin system are among the most robust findings in suicidal behavior and in impulsive aggression, we hypothesized that DNA polymorphisms affecting serotonin-related genes may be the molecular basis of the genetic vulnerability to suicidal behavior (SB). Six hundred patients consecutively admitted to our psychiatric departments after a suicide attempt, and 239 controls were included in this study. Single nucleotide polymorphisms and microsatellite in the genes coding for tryptophan hydroxylase (TPH) and MAOA have been genotyped. Clinical and laboratory methods described elsewhere. We confirmed the association previously reported between suicide attempt and variants in TPH introns 7, 8 and 9 (these loci are in complete linkage disequilibrium): f (AA) ¼ 9.6% in controls and 18.1% in SA, f (A) ¼ 34.3% and 41.2 respectively, P ¼ 0.009, and in the 30 noncoding region (P < 0.01), and the fact that association was strongest for subjects who had attempted suicide by violent means (f (AA) ¼ 23.1% and f (A) ¼ 45.5%; P ¼ 0.001). No association was observed between MAOA and suicide attempt in the overall sample, but in women a slightly significant difference was observed between the short intron 2 MAOA allele and violent SA. In conclusion, we confirm, in a large sample, the association we and other have previously reported between the A218 intron 7 TPH polymorphism and SB. A similar association has been observed with several psychiatric disorders suggesting that TPH may be involved in a common phenotype, probably related to impulsivity-aggressivity.

Slide Session 11: Neurological and Psychiatric Childhood Diseases III O61 A META-ANALYSIS OF LINKAGE AND ASSOCIATION BETWEEN THE DOPAMINE TRANSPORTER GENE (DAT1) AND CHILDHOOD ADHD Waldman I Emory University, Department of Psychology, Atlanta, GA Recently, a number of studies have examined association and linkage between candidate genes in the dopaminergic neurotransmitter system and childhood attention-deficit hyperac-

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tivity disorder (ADHD). Several studies have demonstrated association and linkage between ADHD and a number of these genes, specifically the dopamine receptor D4 and D5 genes (i. e., DRD4 and DRD5) and the dopamine transporter gene (i. e., DAT1). Nonetheless, a number of studies also have failed to replicate these relations. In this study, we examine linkage and association between ADHD and a functional polymorphism in the 30 untranslated region of DAT1 via a meta-analysis of effect sizes derived from transmission disequilibrium test results from 15 independent samples. We tested for association and linkage between DAT1 and ADHD (i. e., whether the relative risk [RR] was significantly greater than 1 across studies, as well as whether there was significant heterogeneity in the effect sizes. We also conducted similar analyses for DRD4 and ADHD to compare the magnitude of effect sizes to that for DAT1. Preliminary results from 10 samples suggest significant association and linkage of both DAT1 and DRD4 with ADHD (RR ¼ 1.3, P ¼ 0.054 and RR ¼ 1.4, P ¼ 0.004, respectively). Despite the similar relative risks for these two genes, their level of significance differed markedly. This is because there was little heterogeneity in the effect sizes for DRD4, but substantial heterogeneity in the effect sizes for DAT1, suggesting that systematic differences in the samples and/or methods of these studies may be contributing to differences in the relation of DAT1 and ADHD. In an attempt to explain the heterogeneity in the DAT1 effect sizes, we are testing for the potential moderating role of several variables, including the magnitude of DRD4 effect size, the location of the study (i. e., US/Canada versus UK/Europe/Asia), the proportion of ADHD subtype diagnoses (i. e., Combined versus Inattentive type), the rates of overlapping diagnoses (e. g., of Oppositional Defiant and Conduct Disorder), the proportion of male participants, and the assessment method used (i. e., interview versus questionnaire). O62 A GENOME WIDE SCAN OF 166 DUTCH SIBPAIRS WITH ATTENTION-DEFICIT HYPERACTIVITY DISORDER Van der Meulen EM,1 Bakker SC,2 Sandkuijl LA,6 Pauls DL,3 Monsuur AJ,2 Van ‘t Slot R,2 Minderaa RB,4 Gunning WB,5 Wijmenga C,2 Pearson PL,2 Buitelaar JK,1 and Sinke RJ2 1 Department of Child and Adolescent Psychiatry and 2 Department of Medical Genetics, University Medical Center Utrecht, The Netherlands 3 Unit of Psychiatric and Neurodevelopmental Genetics, Massachusetts General Hospital 4 University Center for Child and Adolescent Psychiatry Groningen, The Netherlands 5 University Center for Child and Adolescent Psychiatry Amsterdam, The Netherlands 6 Department of Medical Statistics, Leiden University Medical Center, The Netherlands A genome scan was performed in 106 Dutch affected sibpair (ASP) families with Attention-Deficit Hyperactivity

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Disorder (ADHD). All subjects were of Dutch (Caucasian) descent and were phenotyped according to DSM-IV criteria. A narrow phenotype was defined in which all sibpairs met full ADHD criteria (117 ASPs). Additional sibpairs in which one child had an autistic spectrum disorder (apart from meeting ADHD criteria) were included in a broad phenotype group (166 ASPs). Initially, a set of 402 polymorphic microsatellite markers, with an average intermarker distance of 10 cM, was genotyped and analyzed using Mapmaker/sibs. Sibpairs were weighted in families with more than 2 affected siblings. Regions with multipoint LOD-scores (MLS) >1.5 were fine mapped with additional markers. This reduced marker distances to 2.0 were observed with markers on 2q31.1, 4q32, 12q23, and on Xq25, a locus already earlier identified in one extended Finnish pedigree. In the second stage of the genome-wide scan we fine mapped

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four chromosomal regions with additional family members on 2q31.1, 4q32, 12q23.2 and 16p11.1 that provided suggestive evidence of linkage (Zmax > 2.0). All of these regions replicated earlier linkage findings in either bipolar disorder or other mental disorders. We also carried out a joint linkage analysis by combing the raw data from two genomewide scans, the previously mentioned and a schizophrenia genome-wide scan, also carried out with Finnish study sample. Our aim was to localize potential loci predisposing to a broader psychotic phenotype. Two diagnostic categories were assigned to this combined data set; 1) families diagnosed with psychotic disorder and 2) families diagnosed with mood disorder. The total study sample, 2198 subjects from 313 families were screened with 339 markers spaning the genome. Twenty-seven loci exceeded a Zmax >1.0, of them 4 exceeded a Zmax of 2.0 on chromosomes 1q32 (Zmax ¼ 2.48), 4q32 (Zmax ¼ 2.62), 5q11 (Zmax ¼ 2.56) and Xq25 (Zmax ¼ 2.45). Even though the size difference between the study samples was evident, all loci except for 5q11 represented linkage peaks also seen in the bipolar genome-wide scan. These chromosomal regions might represent psychosis loci rather than loci predisposing to pure bipolar disorder. P18 DEVELOPING QUANTITATIVE TRAITS FOR BIPOLAR GENETICS USING THE TCI-125 Evans LM, Akiskal HS, and Kelsoe JR Department of Psychiatry, University of California, San Diego, and San Diego VA Healthcare System, San Diego, California Bipolar (BP) disorder is most likely a polygenic trait resulting from numerous interactions between genes of small effect. One approach to uncovering these genes of small effect is to develop quantitative traits for use with linkage analysis. Quantitative traits measure continuous variation on a particular characteristic ranging from normal to pathological. In this study, we examine the 7 scales of Cloninger’s Temperament and Character Inventory-125 (TCI-125) as potential quantitative traits. To this end, we administered the TCI-125 to 85 BP families and 63 control subjects. The first identified BP family member diagnosed as BPI, BPII, or schizoaffective-BP type was classified as a proband. Other family members were placed into one of two groups. They were classified as affected relatives if they were diagnosed as having BPI, BPII, schizoaffective-BP type, or major depression-recurrent, and they were classified as unaffected relatives if they did not have any of these diagnoses. Control subjects without any psychological diagnosis and having no family history of any such disorders were placed into a fourth group. These 4 groups were compared on each of the 7 scales of the TCI-125. The self-directiveness and self-transcendence scales gave the most promising results based on analyses with ANOVAs (P < 0.001 for both) and the Tukey

HSD. These 2 scales showed significant differences between groups that are more difficult to distinguish. For example, the self-transcendence scale revealed a significant difference between the controls and unaffected relatives with the Tukey HSD (P ¼ 0.03). The cooperativeness, harm avoidance, and novelty seeking scales seemed to be able to differentiate between those with and those without bipolar spectrum disorders (P < 0.001 for all three) but was unable to distinguish between groups with more subtle diagnostic and genetic loading differences in the post hoc comparisons. The persistence and reward dependence scales showed no differences across groups (P ¼ 0.55 and P ¼ 0.7, respectively). P19 A GENOME WIDE SCAN SHOWS SIGNIFICANT LINKAGE BETWEEN BIPOLAR DISORDER AND CHROMOSOME 12q24.3 AND SUGGESTIVE LINKAGE TO CHROMOSOMES 1p22-21, 4p16, 6q14-22, 10q26 AND 16p13.3 Ewald H Institute for Basic Psychiatric Research, Aarhus University Hospital, Denmark The present study reports a genomewide scan using linkage analysis for risk genes involved in bipolar disorder with 613 microsatellite markers including additional testing of promising regions. We found significant linkage to chromosome 12q24.3 with a two-point parametric lod score of 3.42 at D12S1639 including all members in both families (empirical P value 0.00004, genome-wide P value 0.0417), and a multipoint parametric lod score at D12S1639 of 3.63 (genomewide P value 0.0265), which increased to 4.19 (genome-wide P-value 0.0077) when including a bilineal subbranch. At chromosome 1p22-p21 we found a parametric, affectedsonly two-point lod score of 2.75 at marker D1S216 (empirical P-value 0.0002, genome-wide P value 0.1622) and a three-point lod score of 2.98 (genome-wide p-value 0.1022) at D1S216, which were supported by multipoint nonparametric analyzes with a maximum NPL-all score of 17.60 (P-value 0.00079) around D1S216 when only including the larger family. A number of additional loci on chromosomes 4p16, 6q14-q22, 10q26 and 16p13.3 yielded parametric lod scores around or above 2. Molecular Psychiatry, in press. P20 MANIC DEPRESSIVE ILLNESS IN A FOUNDER POPULATION Heyer E,1,2 Perri C,3 Toupance B,1,2 De Vito O,3 Foncin J-F,4 and Bruni AC3 1 Laboratoire d’Anthropologie Biologique, Museum National d’Histoire Naturelle, Paris, France 2 Universite´ Paris 7, Paris, France 3 Centro Regionale di Neurogenetica, ASL17, Lamezia Terme, Calabria, Italy 4 Laboratoire de Neurohistologie, Ecole Pratique des Hautes Etudes, Brie Comte Robert, France

Abstracts

Manic Depressive Illness (MDI) segregates within a founder population originating from S, a mountain village in Southern Italy. Due to high consanguinity and incomplete penetrance, identity by descent of affected persons cannot be established by direct genealogical methods. We established a data base encompassing the whole population of S in the 17th and 18th centuries, and part of the population of S and of neighbouring villages to the present; it comprises 56.000 persons, with 984 founders. We selected 10 MDI probands in descent of members of the S population, and not evident close relatives of each other. Ten other MDI probands originating from other villages formed a first control group. 10 AD patients from the FAD4 family, which originates within the S population, formed a second control group. We computed the genetic contribution of each founder to each proband. The distance between two probands was calculated in respect to all founders and to the founders specific to S MDI probands. Distance matrices were represented by standard principal component analysis. 17 founders are present in the ascendancy of all individuals of the S MDI group and are not present in the ascendancy of the control groups: MDI patients are derived from a relatively independent subpopulation within S. If there is a common genetic factor for MDI within population S, this factor is inherited from (at least) one of the 17 ‘‘specific’’ founders. Two S MDI probands are far from one another in respect of the ‘‘non-specific’’ founders, but are very close in respect of the specific founders. This reinforces the hypothesis according to which a MDI trait originated from specific founders of the MDI subpopulation. These results could have relevance to nosology and molecular genetics studies of MDI. P21 ASSOCIATION BETWEEN SEROTONIN TRANSPORTER GENE AND NEUROENDOCRINE HORMONES AMONG ADOLESCENTS WITH DEPRESSION AND CONTROLS Ghaziuddin N,1 Rozek LS,1 Hanna G,1 and Cook E2 1 University of Michigan, Ann Arbor, Michigan 2 University of Chicago, Chicago, Illinois The aim was to study association between the genetic variation in the serotonin transporter gene (5HTT) as measured by genotype and haplotype and serotonergic neuroendocrine hormones (growth hormone, GH; cortisol; prolactin, PRL) among adolescents with major depression (MDD) and controls. 36 subjects (age range ¼ 13–22 years, mean age ¼ 15.4 þ 2.1; F ¼ 15, M ¼ 21; MDD ¼ 20, controls ¼ 16) were studied. Hormones were measured at baseline and following saline and mCPP infusions. Subjects with genotype s/s and s/l were grouped together (group 1; n ¼ 26) and compared with l/l genotype (group 2; n ¼ 10). Haplotype group was based on previous studies of functional class for platelet uptake as defined by three sites: HTTLPR, genotype at HTTSNP10 and genotype at HTTSNP11. Group 1 (n ¼ 16) included

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HTTLPR s/s or s/l NOT T/T for HTTSNP10 and NOT T/T for HTTSNP11. Group 2 (n ¼ 20) included a) HTTLPR s/s or s/l AND T/T for HTTSNP10 AND T/T for HTTSNP11 and b) HTTLPR l/l independent of HTTSNP10/HTTSNP11 haplotype. Repeated measures ANOVA was used to compare hormone levels. 1) 5HTTLPR genotype and haplotype were similarly distributed among depressed and controls; 2) PRL response over time to mCPP among genotype 2 was more robust but this effect was not evident by haplotype; 3) mCPP infusion resulted in a greater GH response among subjects with haplotype 1 compared to haplotype 2, regardless of MDD/control status. There was a significant time by genotype by MDD/control effect post-saline; control subjects with genotype 2 had a higher peak response. Growth hormone response over time post-mCPP was different between genotypes; the peak GH response among genotype 2 was greater than genotype 1 regardless of MDD case/control status; 4) cortisol was not influenced by MDD/control status, by genotype or by haplotype. These findings suggest that neuroendocrine hormone dysregulation among depressed adolescents is not associated with depression alone, but also with genetic variations at the 5HTT loci. P22 SEARCH FOR A SUSCEPTIBILITY GENE FOR BIPOLAR DISORDER ON CHROMOSOME 12 WITH NOVEL MICROSATELLITE MARKERS Glaser B,1 Kirov G,1 Craddock N,2 and Owen MJ1 1 Neuropsychiatric Genetics Unit, Department of Psychological Medicine, UWCM, Cardiff, UK 2 Molecular Psychiatry Group, Division of Neuroscience, University of Birmingham, UK Several linkage studies have yielded evidence for the involvement of a susceptibility gene for Bipolar Affective Disorder (BPD) on chromosome 12q23-q24.1. Two Caucasian pedigrees that are multiply affected by Bipolar spectrum mood disorder were investigated by members of our department and showed linkage to this region with max lod scores of 2.1 and 3.6 respectively [Craddock et al., 1994; Jones et al., 2002]. Recombination mapping on these two pedigrees defined a critical region of interest on chromosome 12 that encompasses the Darier’s disease gene, ATP2A2. Previous linkage disequilibrium (LD) work with known microsatellite markers could not demonstrate significant disease association. In this project 16 novel microsatellite markers were designed for fine LD mapping restricted to a 2.2Mb section of the critical region. These markers and three GDB markers were analysed in 110 parent-offspring trios and two independent case control samples (sample I: 179 patients/188 controls; sample II: 186 patients/186 controls) using DNA pooling. Five markers (one GDB marker and four novel markers: M14, M19, M23, M25) showed possible association and were individually genotyped in the two case control samples. The location of the

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novel markers was confirmed by radiation hybrid mapping and the distances between them were calculated according to the Golden Path: M14-40kb-M19-130kb-M25-175kb-M23. Analysis of the data in sample I revealed an association between BPD and M14 (P ¼ 0.01) and M19 (P ¼ 0.003). None of the investigated markers was significant in sample II. However, combining sample I and II increased the significance for M19 (P < 0.001) and M23 approached significance (P ¼ 0.06). This finding is consistent with the involvement of a gene in close proximity to these markers. Two predicted genes were found in this region, which are now being screened for mutations.

e.g., DBH, specifically reported to be misexpressed in depressive psychosis.

P23 DOPAMINE B HYDROXYLASE (DBH) GENOTYPES AND RECENT LINKAGE FINDINGS SUPPORT VITAMIN A CASCADE GENES AS CANDIDATES IN PSYCHOTIC DEPRESSISON Goodman AB Department of Psychiatry at Massachusetts Mental Health Center, Harvard Medical School, Boston

The A allele of the 5-HT2A gene has been associated with mood disorders and suicidal risk in different samples, although the association has not been systematically found. The 5-HT2A promoter polymorphisms may be specifically involved in severe mood disorders such as bipolar I disorder, in accordance with our previous results (Bonnier et al., http: //www-east.elsevier.com/bps/abstracts/15764abs.htm). We tested if generalised anxiety disorder could distinguish a sub sample of patients with unipolar depression for whom the vulnerability allele could also have a role, such as the one observed in the group of bipolar I disorder. The hypothesis is that mood disorders occurring after chronic anxious disorder may have other mechanisms, and that patients with unipolar mood disorders without past history of GAD may be more specifically related to bipolar I. We thus tested the A allele (5-HT2A gene, -1438A/G polymorphism) in 61 French patients with unipolar disorder, taking into account lifetime history of generalised anxiety disorder, and compared them to 226 healthy control patients, and 94 bipolar I patients. Presence of the A allele in patients without lifetime history of GAD was 79% (33/42), which was significantly higher than in the control group of 226 healthy subjects (c2 ¼ 5.28, df ¼ 1, P ¼ 0.022), and also higher than the unipolar patients with GAD (c2 ¼ 4.23, df ¼ 1, P ¼ 0.039), but not from bipolar I subjects (c2 ¼ 1.02, df ¼ 1, P ¼ 0.31). GAD is rarely assessed in psychiatric genetic studies because of its relatively low heritability. It may be that this syndrome may help to disentangle the complexity of the mood disorders spectrum.

Recent reports indicate that although DBH is lowered in plasma and CSF of persons with psychotic depressive disorders, the result is independent of DBH genotype. As DBH is under genetic regulation, this suggests that genes that modulate DBH could account for the effect. Expression of DBH is regulated by retinoic acid (RA), the final product of the vitamin A (retinoid) cascade. In the presence of RA the retinoid nuclear receptors (RARs and RXRs) form heterodimeric partners with other nuclear receptors, e.g., NURR1, the PPARs and thyroid hormone receptors. These heterodimers bind to target genes, including those suggested as candidates in psychosis, e.g., DBH, dopamine receptors, tyrosine hydroxylase, serotonin receptors, GABA receptors, glutamic acid decarboxylase, nitric oxide synthase, and various myelin-related genes. This RA-regulated binding initiates transcription of the target genes. RA synthesis is mechanized by retinoid cascade enzymes, binding proteins, and transporters. These convert dietary vitamin A in the form of retinol, originally present in the intestines and liver, to various forms of morphogenic RA eventually carried to and synthesized in the brain. The loci of several of the genes in this cascade have been strongly linked to depressive psychosis, i.e., the nuclear receptor, RARB at 3p24 [Edenberg et al., 1997; Pulver et al., 2000]; the lipocalin retinoid transporter, APOD at 3q27 [Kelsoe et al., 2001]; retinol binding protein (RBP) 3 at 10q11.2 [Claes et al., 2002]; RPB4 at 10q24 [Cichon et al., 2001; Ewald et al., 2002]; the retinol/ RBP and choroid plexus transporter, transthyretin (TTR) at 18q12.1 [Maziade et al., 2001]. Taken together the high LOD scores at these various vitamin A cascade loci strongly implicate retinoids in psychotic depression. This finding is particularly relevant in the absence of mutations in genes,

P24 THE A ALLELE OF THE 5-HT2A GENE IS ASSOCIATED WITH UNIPOLAR DEPRESSION WHEN EXCLUDING PATIENTS WITH LIFETIME GENERALISED ANXIETY DISORDER Gorwood P,1,2 Boyer P,2 Bonnier B,3 Serfati Y,3 Ade`s J,1 Hardy-Bayle MC,3 Boni C,4 and Hamon M4 1 Hoˆpital Louis Mourier (AP-HP, Paris VII), Service de Psychiatrie, Colombes, France 2 CNRS UMR 7593, CHU Salpe´trie`re, Paris, France 3 Hoˆpital Mignot. Service de Psychiatrie, Le Chesney, France 4 INSERM U 288, CHU Pitie´-Salpeˆtrie`re, Paris, France

P25 FUNCTIONAL ANALYSIS OF THE REGULATION OF DOPAMINE TRANSPORTER GENE EXPRESSION Greenwood TA, Kelsoe JR Department of Psychiatry, University of California, San Diego A role for the dopamine transporter (DAT) gene in bipolar disorder is implicated by several lines of pharmacological evidence, as well as suggestive evidence of linkage at this

Abstracts

locus. TDT analysis of a sample of 50 parent-proband triads from our UCSD/UBC/UC family collection revealed the 30 region of the DAT gene (exon 9 through exon 15) to be in strong linkage disequilibrium (LD) with bipolar disorder (P ¼ 0.0004). Subsequent analysis of an additional 70 triads from the NIMH bipolar collection revealed more modest evidence for association to a region slightly 50 of that originally implicated (intron 2 through intron 10). As these two regions exhibit an overlap defined by four polymorphisms deriving from exon 9, intron 9, and intron 10, it is possible that a functional variant contributing a susceptibility to bipolar disorder exists within or near this region. Since LD analyses did not enable us to more precisely localize the region containing the putative functional variant, we have attempted to identify such a variant by analyzing the effect on expression of a number of the potential regulatory and intronic regions within the DAT gene. These analyses indicate a strong core promoter and potential repressor elements in both the proximal 50 flanking region and intron 1. A 1.5-fold difference in regulatory activity was also observed between the different haplotypes of these promoter segments, representing the two 50 clades. We found no effect on transcription with inclusion of the 9- and 10-repeat alleles of the 30 VNTR. However, introns 9, 12, and 14 appear to contain enhancer elements capable of increasing expression approximately 2-fold with respect to the promoter constructs. There also appear to be differences in expression between two alleles of intron 14, as well as between haplotypes comprised of different alleles of the promoter and exon 9/intron 9. These results thus indicate that it may be the particular combination of polymorphisms in a haplotype across the gene that ultimately effect DAT gene expression. P26 IS BIPOLAR DISEASE A NEURODEGENERATIVE DISEASE? Himmelhoch JM University of Pittsburgh School of Medicine, UPMC, Western Psychiatric Institute, Pittsburgh, Pennsylvania The absence of phenotypic specificity has made the search for susceptibility genes for bipolar disorders an uncertain adventure. Thought provoking loci have been identified only to be unreplicable: an outcome that occurs regularly in genomic studies of common illnesses with proposed polygenic inheritances. Still, if the results from many such gene scans were to be combined, the statistical power might be achieved for meta-analyses to show linkages in specific chromosomal regions. The question remains, what characteristic of bipolarism might yield to the strategy of positional cloning? The author proposes recent re-conceptualization of bipolar illness as a neurodegenerative disorder. In 1893, Kraepelin suggested that severe manic-depressive illness evolves into dementia. His idea had a hostile reception and has lain fallow; but it has been reconsidered in light of recent MRI volu-

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metric findings from the brains of treatment-resistant [rapidcycling] patients. Among the CNS degenerative illnesses, Parkinsonism has the most clinical therapeutic similarities to bipolarism. It seems reasonable to suggest that scrutiny of the domains where genes [and gene products] known to be involved in Parkinsonism and/or other such degenerative disorders are found is a domain where bipolar susceptibility loci may also be discovered. P27 LINKAGE ANALYSIS OF CHROMOSOME 1 MARKERS IN A SIBLING STUDY OF DEPRESSION AND ANXIETY (GENESIS) Huezo-Diaz P, Nash MW, Stern A, Williamson R, Purcell S, Craig I, and Sham P Social, Genetics & Developmental Psychiatry Research Centre, Institute of Psychiatry, London, UK There is considerable evidence for a unitary and dimensional view of genetic vulnerability to symptoms of anxiety and depression [Kendler et al., 1995; McGuffin et al., 1994; Plomin et al., 1997]. The GENESIS (Genetic and Environmental Nature of Emotional States in Siblings) project aims to use a multivariate approach to detect Quantitative Trait Loci that contribute to individual differences in these vulnerability dimensions [GENESIS; Sham et al., 2000]. Phenotypic information was collected on anxiety (MASQAA), depression (MASQ-HPA), neuroticism (EPQ-N) and current psychological state (GHQ-12) from >30,000 individuals in the UK. These four scales were standardised and combined to form a composite index, which was used to select the top 5% informative sibships for DNA collection and linkage analysis [Purcell et al., 2001]. We are currently undertaking a genetic linkage scan using 379 individuals from 174 sibships. We have completed genotyping these families with 31 markers on Chromosome 1 (ABI MD10 linkage set). Linkage analysis using MERLIN [Abecasis et al., 2000] showed two small clusters of modestly significant LOD scores (P < 0.001). These preliminary results suggest that chromosome 1 may contain QTLs associated to anxiety and depression. P28 SOMATIC COMPLAINTS AND SOMATOSENSORY ERPs AS VULNERABILITY MARKERS FOR AFFECTIVE DISORDERS Ising M, Adena S, Binder E, Huber J, Holsboer F, and Modell S Max Planck Institute of Psychiatry, Munich, Germany In an ongoing research project, we investigate possible vulnerability markers for affective disorders in families with at least three affected members. Besides a genetic analysis, neurobiological and psychometric variables are assessed. Eight families with 46 risk probands (RP) are currently included. 17 RP did not show any current or lifetime history of psychiatric disorders, while 29 RP suffered previously

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from a psychiatric disorder and 11 of them were affected at the time of the investigation. In accordance with recent results, we observed an elevated tendency to report and experience somatic sensations and complaints in remitted RPs as well as in currently affected RPs. We hypothesized that subjective somatic complaints are associated with an elevated EEG response to somatosensory stimulation (ERPs). ERPs were assessed during 8 consecutive blocks of 6 minutes of somatosensory stimulation at the left index finger. The level of stimulation was determined as the 2.5fold intensity of the individual perception threshold. As previously proposed, response strength (square root of amplitude variability) of two time intervals were calculated (RS1/RS2: 50–150 ms/170–370 ms after stimulation). In a preliminary analysis of the first 25 cases, we could not find significant differences between affected and unaffected RPs. However, we observed a distinct positive association between the somatosensory RS2 component of fronto-central midline leads and subjective somatic complaints (r ¼ 0.47, P < 0.05), while the RS1 component was negatively associated with depressive symptoms (BDI, r ¼ 0.46, P < 0.05). These associations cannot be attributed to medication effects as they were even more pronounced, when only medication-free RPs were considered. We conclude that late component of somatosensory ERPs serve as an objective indicator of the subjective somatic complaints and can be considered as a promising endophenotype in the research on genetic vulnerability in affective disorders. P29 X LINKAGE IN BIPOLAR DISORDER: ALLELIC ASSOCIATION STUDIES OF THE Xq26-28 REGION IMPLICATE THE G6PD LOCUS AND FLANKING REGION BUT NOT THE a3 SUBUNIT OF THE GABA RECEPTOR GENE (GABRA3) IN A UK BIPOLAR CASE-CONTROL SAMPLE Kalsi G, Lawrence J, Mcquillin A, Curtis D, Bass N, and Gurling HMD Molecular Psychiatry Laboratory, Department of Psychiatry and Behavioural Sciences, Royal Free and University College London Medical School, Windeyer Institute of Medical Sciences, University College London, UK An excess of affected females and a deficiency of male-tomale transmission has led to the proposal of an X-linked form of bipolar illness and several studies have investigated the region Xq26-28. Early studies using phenotypic markers highlighted a possible link between Glucose-6-Phosphate Dehydrogenase (G6PD) on Xq28 and bipolar illness. More recently the a3 subunit of the gamma amino butyric acid receptor gene (GABRA3) has received attention on the basis of preclinical and pharmacological studies, which suggest that a dysfunction in brain GABAergic system activity could contribute to manic depression. Thus, the a3 subunit localized on the Xq28 region, represents a plausible

candidate gene. Previous linkage and association studies using molecular markers have shown mixed results. We tested the dinucleotide (CA) polymorphism of the GABRA3 gene, found near the 30 end in intron 8 of the gene, in a stringently screened sample of 306 UK bipolar affective patients of English, Irish, Welsh or Scottish ancestry and compared allele frequencies in 310 ethnically matched normal controls. The data was analysed using the CLUMP program. Our study does not find statistically significant difference in the allele frequencies between cases and controls for any of the alleles. The combined analysis of males and females produced P ¼ 0.3237 whilst a females only analysis showed P ¼ 0.5440. These results are not in line with a recent report by Massat et al. [2002], which showed an excess of one of the alleles in a multicentre association study, but it is consistent with previous association studies, which also showed a lack of association between the GABRA3 polymorphism and bipolar disorder. P30 LINKAGE ANALYSES OF BIPOLAR AFFECTIVE DISORDER ADD SUPPORT FOR A SUSCEPTIBILITY LOCUS ON 10q25-q26 Kaneva R,1,3 Valtchanova R,1 Chorbov V,1 Milanova V,2 Kostov C,2 Schumacher J,3 Stoyanova V,2 Nikolova A,2 Onchev G,2 Gaidarova R,4 Krastev S,2 Cichon S,5 Kremensky I,1 No¨then MM,5 and Propping P3 1 Laboratory of Molecular Pathology, Medical University of Sofia, Bulgaria 2 Department of Psychiatry, Medical University of Sofia, Bulgaria 3 Institute of Human Genetics, University of Bonn, Germany 4 Department of Psychiatry, Medical University of Pleven, Bulgaria 5 Department of Medical Genetics, University of Antwerp, Belgium Previous linkage studies have provided suggestive evidence for a new susceptibility locus for bipolar affective disorder (BAD) on chromosome 10q [Cichon et al., 2001]. As part of an ongoing genome scan for linkage to BAD we attempted to replicate these findings in a sample consisting of 9 Bulgarian families and 3 big families of Gypsy origin. Analyses were done under two definitions of disease phenotype: ‘narrow’, including only BP I, BP II and schizoaffective manic and ‘broad’, including recurrent unipolar depression in addition to the ‘narrow’ model. The total number of affecteds under the ‘narrow’ phenotype model is 39 and under the ‘broad’ model is 65. Eight highly polymorphic markers, implied in former studies and covering about 19 cM were genotyped and parametric (dominant model of inheritance with reduced penetrance) and nonparametric linkage analysis performed. Small positive two-point Lod scores were obtained for markers D10S1757 and D10S1483. Both the multipoint Lod Score analysis and NPL performed by GENEHUNTER

Abstracts

showed a peak at marker D10S1757. A maximum Lod score of 1.89 and an NPL (all) score of 1.57 (P ¼ 0.015) were obtained under the ‘narrow’ model. The result is mainly due to contribution from the families of Bulgarian origin, that alone show a multipoint Lod score of 1.77 and an NPL (all) score of 1.86 (P ¼ 0.019). Although these results do not strictly meet the requirement for replication, they add some support to the hypothesis of a susceptibility locus for bipolar disorder on chromosome 10q26. P31 SUGGESTIVE EVIDENCE FOR LINKAGE OF BIPOLAR DISORDER TO MARKERS AT CHROMOSOME 4p IN BULGARIAN FAMILIES Kaneva R,1,3 Chorbov V,1 Milanova V,2 Kostov C,2 Schumacher J,3 Stoyanova V,2 Nikolova A,2 Onchev G,2 Gaidarova R,4 Krastev S,2 Cichon S,5 Kremensky I,1 Propping P,3 and No¨then MM5 1 Laboratory of Molecular Pathology, Medical University of Sofia, Sofia, Bulgaria 2 First Psychiatric Clinic, Department of Psychiatry, Medical University of Sofia, Bulgaria 3 Institute of Human Genetics, University of Bonn, Bonn, Germany 4 Department of Psychiatry, Medical University of Pleven, Pleven, Bulgaria 5 Department of Medical Genetics, University of Antwerp, Belgium Linkage study in Scottish bipolar families showed evidence of a susceptibility locus for bipolar affective disorder on chromosome 4p16 in at least a proportion of the families [Blackwood et al., 1996]. Replication studies in independent samples produced conflicting results, but still attract attention to this region. As part of an ongoing genome-wide search for loci linked to bipolar affective disorder (BPAD), we tested STR markers in the chromosome 4p16 region for linkage to BPAD in 9 Bulgarian families, each with two or more affected subjects. Six microsatellite markers, implicated in former studies and covering about 29 cM of 4p16 were genotyped. Two phenotype models (‘narrow’: BPI, BPII and schizoaffective manic; ‘broad’: including recurrent unipolar depression in addition to the diagnoses in the ‘narrow’ phenotype) were used. Small positive two-point Lod scores were obtained for all markers under a dominant model of inheritance with reduced penetrance and ‘narrow’ phenotype definition. A maximum of 1.59 was observed at marker D4S394, that yielded the best linkage result in the study by Blackwook et al. [1996]. Parametric MLS and NPL analyses performed by GENEHUNTER under the same model produced two peaks: at marker D4S394 (MLS ¼ 1.86, NPL ¼ 1.92, P ¼ 0.01); and at marker D4S419 (MLS ¼ 1.94, NPL ¼ 2.75, P ¼ 0.00037). The results under the ‘broad’ phenotype definition were not significant. Our findings support the initial linkage report and provide suggestive

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evidence for a susceptibility locus on 4p in Bulgarian families with bipolar affective disorder. P32 CHROMOSOME 14q22-24 AND BIPOLAR DISORDER: FURTHER LINKAGE STUDIES, MUTATION SCREENING OF CANDIDATE GENE, GCHI, AND NOVEL SNP ASSOCIATION STUDY Kealey C,1 Mynett-Johnson L,1 and McKeon P2,3 1 Department of Genetics, Smurfit Institute, Ireland 2 Department of Psychiatry, Trinity College Dublin, Ireland 3 The Depression Research Unit, St. Patrick’s Hospital, Dublin, Ireland A modified genome scan of Irish bipolar disorder sib-pair nuclear families previously conducted by this group highlighted a region of chromosome 14 (q22-24) as possibly harbouring a susceptibility locus for bipolar disorder. Multipoint linkage analysis was performed over an 85 cM region spanning the original markers D14S271 and D14S281, and while the flanking markers appear to support the original observations, we were unsuccessful in significantly narrowing down the region of interest by the inclusion of additional markers. This region of chromosome 14 was searched for the presence of putative candidate genes using the databases, ENSEMBL (www.ensembl.org), NCBI (www.ncbi. nlm.nih.gov), UCSC human genome project working draft (www.genome.ucsc.edu/golden). Of the genes found in this region, it was decided to further investigate the GTP cyclohydrolase I gene. GTP cyclohydrolase I (GCHI) is the rate limiting enzyme for the biosynthesis of tetrahydrobiopterin (BH4) in mammals. It is required for the enzyme activities of tyrosine and tryptophan hydroxylases, which are the rate limiting enzymes for catecholamine and serotonin biosynthesis. The GCHI gene has been localised to 14q22.1-q22.2, is comprised of 6 exons and spans approximately 30 kb (Ichosinose et al., 1994). All six exons, 50 UTR and 1122 base pairs of the promoter region were screened for mutations using denaturing high performance liquid chromatography (DHPLC) in a sample of 15 BPI patients and 15 controls. No single nucleotide polymorphisms (SNPs) were detected in the coding or 50 UTR regions but 4 SNPs were found in the promoter region, 2 of which are novel. We present here an association study between bipolar disorder and a novel SNP found in the promoter region of the GCHI gene (G to A at position 959 upstream of ATG codon) in the Irish population. P33 A COMPARISON OF CLINICAL FEATURES IN FAMILIAL EARLY AND ADULT ONSET BIPOLAR DISORDER Kent L, Heron J, Gordon-Smith K, and Craddock N Molecular Psychiatry Group, Division of Neuroscience, University of Birmingham, UK A number of studies have reported differences in psychopathology between adolescent onset and adult onset bipolar

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disorder (BP). Early onset BP is more familial than adult onset and differences in familiality may confound the reported differences in psychopathology. We aimed to compare phenomenology between early and adult onset BP subjects who all have a positive family history for BP thereby removing family history as a possible confounder. From a large BP dataset with increased familial loading for illness, unrelated subjects with early onset BPI (28 years). All subjects were interviewed with the SCAN and fulfilled DSMIV BPI criteria. Results demonstrated that there was more psychosis, rapid cycling, suicidality and less chronicity of illness in the early onset group although differences were less than in some previous reports. In conclusion, family history may act as a partial confounder in studies comparing early and late onset BP disorder but there are differences in several clinical features that appear to be independent of familial loading for illness. P34 DECLARATIVE MEMORY DIFFERENTIATES BIPOLAR TWINS, HEALTHY CO-TWINS, AND CONTROLS Kieseppa¨ T,1 Haukka J,1 Tuulio-Henriksson A,1 van Erp TGM,2 Glahn D,2 Juselius S,1 Pirkola T, Cannon TD,2 Kaprio J,1,3 and Lo¨nnqvist1 1 Department of Mental Health and Alcohol Research, National Public Health Institute, Helsinki, Finland 2 Department of Psychology, UCLA, California 3 Department of Public Health, University of Helsinki, Finland We present neuropsychological test battery results of 30 euthymic bipolar twins, 29 healthy co-twins, and 123 healthy control twins. We calculated four factor solution and factor scores using principal factor analysis. The number of factors was defined by maximum likelihood factor analysis. We named factors as 1. a declarative memory, 2. a working memory, 3. an abstraction, and 4. a visuospatial factor. The factors explained 42% of the variance, and the first factor explained 14% of the variance. Only the first factor scores differentiated significantly (F ¼ 8.04; P < 0.001) the three patient groups. Mean factor scores were 0.55 for bipolar twins, 0.17 for co-twins, and 0.27 for controls. Binary classification tree analysis (CART) revealed that the best discriminator between controls and bipolar twins or co-twins was the total number of remembered items in CVLT. The best discriminator between bipolar twins and co-twins was a hit reaction time calculated from CPT, which reflects sustained attention and information processing speed. Declarative memory might serve as a trait marker for bipolar disorder, and it may also be impaired in healthy relatives. Defect in sustained attention was more typical among those who had developed bipolar disorder.

P35 SYMPTOM PATTERNS AND SIBLING CORRELATIONS IN THE DEPRESSION NETWORK (DENT) STUDY Korzsun A,7 Farmer AE,2 MoskvinaV,7 Machin P,2 James Rantell,2 Moore JH,1 Brewster S,3 Jones L,4 Craddock N,4 Ferrero F,5 Abood Z,6 Gill M,6 Fangerau H,8 Ohiran S,8 Reitschel M,8 Maier W,8 Mors O,9 Horsboell H,9 Kirov G,7 Owen MJ,7 Preisig M,10 Reich T,11 Drain C,11 Haines JL,1 Moore J,1 and McGuffin P2 1 Vanderbilt University, Nashville, Tennessee 2 Institute of Psychiatry, London, UK 3 GlaxoSmithKline, UK 4 University of Birmingham, UK 5 Geneva University Hospital, Switzerland 6 St James’s Hospital, Dublin, Ireland 7 University of Wales College of Medicine, Cardiff, UK 8 University of Bonn, Germany 9 Psychiatric Hospital, Aarhus, Denmark 10 University Department of Adult Psychiatry, Lausanne, Switzerland 11 Washington University, St. Louis, Missouri The depression network study (DeNt) is a large scale multicentre collection of families containing two or more siblings affected by recurrent unipolar depression; its design has been described by Moore et al. (2002). Here we present clinical data on the first 242 affected sib pairs collected. As might be predicted in a sample collected specifically for a high familial loading, there was a high prevalence of biological or ‘endogenous’ symptoms. These included appetite change (79%), weight loss (59%) and sleep disturbance (85%), as well as diurnal variation of depressed mood with morning exacerbation (55%). Abnormal ideation in the form of simple ideas of reference (52%) or guilt (70%) was common, although only a minority of subjects (5%) were frankly deluded. There was a moderate degree of sibling homotypia for endogenous symptoms with significant correlations for diurnal variation of mood, weight loss, early morning waking, simple ideas of reference and guilt, delusions of guilt and the subjective experience of psychomotor retardation. These preliminary findings indicate the potential usefulness of taking symptom patterns into account in linkage and sib pair association analysis. The target sample size in the DeNT study is at least 900 families making such an analysis feasible.

P36 THE COMBINED DEXAMETHASONESUPPRESSION/CORTICOTROPIN-RELEASINGHORMONE(CRH) STIMULATION TEST, A POSSIBLE ENDOPHENOTYPE FOR MAJOR DEPRESSION? Kuenzel HE, Binder EB, Nickel T, Ising M, Fuchs B, Modell S, and Holsboer F Max Planck Institute of Psychiatry, Munich, Germany

Abstracts

The contradicting results of human genetic studies of depressive disorders suggest that there may be biological/ genetically different subtypes of major depression. Abnormalities in the hypothalamic-pituitary-adrenal (HPA) axis have been shown to contribute to depressive symptomatology. A hyperactivity of the HPA axis has been detected in some but not in all patients. The combined dexamethasone-suppression/CRH-stimulation test (DCT) is a sensitive tool to investigate HPA axis changes in depressed patients. In this present study the value of the DCT as possible endophenotype to distinguish between biologically different subtypes of major depression was investigated. Factors influencing the magnitude of cortisol and ACTH response in the DCT in acutely ill patients as well as in remission were analysed. Investigation in 230 patients showed that the DCT in acutely ill patients is influenced by gender, age, nicotine consumption and pharmacotherapy in addition to depression related factors such as the number of previous episodes and the course of depression. When investigating the changes in cortisol and ACTH response in the DCT from admission to discharge three distinct patterns could be detected. 40% showed an initial hyperactivity in the DCT that normalized with remission, around 30% did not display significant changes in HPA activity and the last 30% showed an increase in ACTH and cortisol values from admission to discharge. The first group contained patients who were more likely to respond rapidly to treatment, to be bipolar or psychotic or have a positive family history. The second group contained patients who tended to have a more chronic disorder and have a negative family history. Previous data from our group strongly indicated that patients in the last group were very likely to relapse within the next 6 months after discharge. Thus the DCT may be able to differentiate biological subentities of patients with a depressive syndrome. The value of the DCT to serve as an endophenotype is currently tested in candidate gene association studies. P37 THE WELLCOME TRUST UK/IRELAND BIPOLAR SIBLING PAIR STUDY: PRELIMINARY REPORT FOR CHROMOSOME 2 AND 10 Lambert D,1 Segurado R,1 Bort S,1 Mulcahy T,1 Craddock N,3 and Gill M1,2 1 Neuropsychiatric Genetics, Department of Genetics, Trinity College Dublin, Republic of Ireland 2 Department of Psychiatry, Trinity College, Dublin, Republic of Ireland 3 Department of Psychiatry, Queen Elizabeth Psychiatric Hospital, UK Our preliminary 2nd stage analysis includes data for the chromosome 2 and chromosome 10 follow-up regions. Chromosome 2 first stage GENEHUNTER analyses have generated an NPL statistic of 1.06 for our ‘narrow’ model (BPI only) with our broadest model (Bipolar I, II, SA/BP, BP

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(NOS), RUP) yielding the highest NPL of 1.45, both at 263 cM (K). Multipoint Lod Scores (MLS) were 0.86 and 1.69 respectively at these positions. Analyses were performed on the total sample set prior to grid tightening in the follow-up region D2s126 to D2s125. Results show elevated NPL scores of 1.75 under the ‘narrow’ diagnostic model at 265 cM (K), with the highest NPL signal of 2.72 (P ¼ 0.003) from our ‘broad’ model at 262 cM (K). MLS scores generated using MAPMAKER/SIBS have shown corresponding increases to 1.88 (narrow) and 2.39 (broad), with the highest score at 259 cM (K) under our intermediate model of 2.52. A chromosome 10 follow-up region spanning markers D10S189 to D10S1652 achieved our minimal threshold of MLS > 0.74. This region is approximately 60 cM (K). The pre-grid tightening analyses have shown the persistence of this peak for the narrow model MLS ¼ 1.28, with the intermediate and broad models increasing to 1.29 and 1.36 respectively. We will present completed chromosome 2 and 10 data using grid tightening to a mean genetic distance of 5 cM. P38 THE WELLCOME TRUST UK/IRISH BIPOLAR SIBLING PAIR STUDY: CHROMOSOME 18 AND PARENT OF ORIGIN EFFECT Lambert D,1 Segurado R,1 O’Mahoney E,2 Mulcahy T,1 Corvin AT,2 Bort S,1 Craddock N,3 and Gill M1,2 1 Neuropsychiatric Genetics, Department of Genetics, Trinity College Dublin, Republic of Ireland 2 Department of Psychiatry, Trinity College, Dublin, Republic of Ireland 3 Department of Psychiatry, Queen Elizabeth Psychiatric Hospital, UK Nineteen defined regions (MLS > 0.74; equivalent to a nominal pointwise significance of 5% under the narrow BP-I model) across the human genome have been identified as hotspots for grid tightening in our two stage, sampling splitting, strategy for genome scanning using affected sibling pairs. Presented are the final results for two such regions localised to chromosome 18. Non-parametric statistics have been generated using GENEHUNTER and MAPMAKER/ SIBS. First stage data for chromosome 18 (GENEHUNTER: NPL ¼ 2.1, P ¼ 0.017 at 17 cM (K) and NPL ¼ 1.9, P ¼ 0.0113 at 98 cM (K) distal to pter; MAPMAKER/SIBS: MLS ¼ 1.5357 at 17 cM (K) and at 78 cM (K) distal to pter, MLS ¼ 1.2309) have prompted further investigation into parent-of-origin effect in these regions. Families were determined to be either maternal, paternal, bilineal or unknown according to the criterion of McMahon et al., 1997. Thirty seven maternal families, 21 paternal and 11 bilineal in a total data set of 161 nuclear families were analysed as a 2nd stage genome wide scan data set. Using this categorisation, maternal pedigrees had shown an increase in allele sharing (z2 ¼ 0.57) equivalent to an MLS ¼ 2.73 at 6 cM (K). With addition of a further 98 sibling pairs 18q peak has diminished

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to NPL ¼ 1.978 P ¼ 0.007 at 87 cM (K); MLS ¼ 1.215 at 83 cM (K). Evidence derived solely from paternal pedigrees (n ¼ 21) is found at 87 cM (K) NPL ¼ 2.06 P ¼ 0.009; MLS ¼ 1.18. P39 CANDIDATE GENES FOR MOOD DISORDERS IN HUMANS. A LITERATURE REVIEW Middeldorp CM,1,2 Ruigrok P,1 Cath DC,2 Van Dyck R,2 and Boomsma DI1 1 Department of Biological Psychology, Free University Amsterdam (VU), The Netherlands 2 Department of Psychiatry, Free University–Medical Center Amsterdam (VU-MC), The Netherlands We present a review of 161 studies concerning the search for genes, which are hypothesized to be responsible for mood disorders (unipolar and bipolar disorder, anxiety disorders) or anxiety related traits (neuroticism, harm avoidance). A total of 133 studies (19 linkage, 109 association and 5 studies using linkage as well as association) are reviewed which focus on genes involved with activity of the serotonin, dopamine, norepinephrin, gamma amino butyric acid system or with enzymes that stimulate their production or degradation of these neurotransmitters. The remaining linkage studies concentrate on particular chromosomes or use markers to screen the complete genome. Despite this large number of studies, a relation between one of the genes under study and mood disorders has not been convincingly demonstrated yet. In general, negative findings outweigh the positive ones, especially when attempts have been made to replicate findings on particular genes. This is best illustrated by the extensive research done on the serotonin transporter gene (17q11.1-q12): 22 positive versus 30 negative results. To date, the most robust negative conclusion that can be drawn is that the dopamine transporter (DAT1) and dopamine receptor D2, D3 and D4 genes are probably not involved in the development of mood disorders. Considering the outcomes of the linkage studies chromosome 18 seems the most promising. It is recommended that linkage studies, taking into account methodological innovations and selection approaches, be used to systematically screen the whole genome and that these results be compared to those from QTL linkage studies using animal models. In addition, alternative models for association, especially those involving gene x environment interaction, should also be considered. P40 DESIGN OF THE DEPRESSION NETWORK (DENT) STUDY TO IDENTIFY SUSCEPTIBILITY GENES FOR UNIPOLAR DEPRESSION Moore JH,1 Farmer A,2 Brewster S,3 Craddock N,4 Ferrero F,5 Gill M,6 Korszun A,7 Maier W,8 Mors O,9 Owen M,7 Preisig M,10 Reich T,11 McGuffin P,2 and Haines JL1 1 Vanderbilt University, Nashville, Tennessee 2 Institute of Psychiatry, London, UK 3 GlaxoSmithKline, UK

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University of Birmingham, UK Geneva University Hospital, Switzerland 6 St James’s Hospital, Dublin, Ireland 7 University of Wales College of Medicine, Cardiff, UK 8 University of Bonn, Germany 9 Psychiatric Hospital, Aarhus, Denmark 10 University Department of Adult Psychiatry, Lausanne, Switzerland 11 Washington University, St. Louis, Missouri 5

Unipolar depression (UD) is a common chronic disease with a complex, multifactorial etiology. The primary objective of the Depression Network (DeNt) study is to identify susceptibility genes for unipolar depression using a two-staged genome scan followed by fine-mapping, candidate gene analysis, and both population- and family-based association analysis in regions of the genome showing significant linkage. The network consists of nine study sites in Europe and the USA that will collect more than 900 families with at least one affected sib-pair. Probands are included in the study if they have had more than one episode of UD, are Caucasian, are at least 18 years old, have given informed consent, and have at least one affected sib that meets the inclusion criteria. Probands that are adopted, have UD resulting from medication, suffer from substance dependency, or have a first or second degree relative with bipolar depression or schizophrenia are excluded from the study. Diagnosis of UD is based on DSM-IV criteria and/or ICD-10 Diagnostic Criteria for Research as determined by the Schedules for Clinical Assessment in Neuropsychiatry (SCAN), a set of instruments aimed at assessing, measuring and classifying the psychopathology and behavior associated with the major psychiatric disorders of adult life. Information about life events is obtained using the Brief Life Events Questionnaire (BLEQ) while personality is assessed using the Eysenck Personality Questionnaire (EPQ). We describe here 400 families that will be included in the first genome scan. P41 AFFECTIVE DISORDERS AND TWO VARIANTS IN THE DOPA DECARBOXYLASE GENE: AN ASSOCIATION STUDY WITH THE DOPA DECARBOXYLASE (DDC) GENE IN A GERMAN SAMPLE Mu¨ller DJ,1 Jahnes E,2 Schulze TG,3 Windemuth C,4 Cichon S,5 Ohlraun S,1 Illes F,1 Fangerau H,1 Held T,6 Maier W,1 Propping P,2 No¨then MM,5 and Rietschel M1 1 Department of Psychiatry, University of Bonn, Germany 2 Institute of Human Genetics, University of Bonn, Germany 3 Department of Psychiatry, The University of Chicago, Chicago, Illinois 4 Department of Medical Biometry, University of Bonn, Germany 5 Department of Medical Genetics, University of Antwerp, Belgium 6 Mental State Hospital, Rheinische Kliniken Bonn, Germany

Abstracts

Irregularities of dopaminergic and/or serotonergic neurotransmission have been implicated in the etiology of affective disorders. DOPA decarboxylase (DDC) is an enzyme involved directly in the synthesis of dopamine and serotonin and indirectly in the synthesis of noradrenaline. Therefore, the DDC gene can be considered as a candidate gene for affective disorders. Recently, two novel variants were reported in the DDC gene: a 1-bp deletion in the promoter and a 4-bp deletion in the untranslated exon 1. Subsequently, an association case-control study including 112 English patients and 80 Danish patients revealed a significant association with the 1-bp deletion in bipolar disorder. This finding prompted us to analyze whether this effect was also present in a larger sample of unrelated German patients with bipolar (n ¼ 228) or unipolar affective disorder (n ¼ 183) and healthy control subjects (n ¼ 234). For both affective disorders we could not detect a genetic association with either variant. Thus, our results do not support an involvement of the 1-bp or 4-bp deletion within the DDC gene in the etiology of affective disorders. P42 THE BRAIN DERIVED NEUROTROPHIC FACTOR GENE CONFERS SUSCEPTIBILITY TO BIPOLAR DISORDER: EVIDENCE FROM A FAMILY-BASED ASSOCIATION STUDY Neves-Pereira M,2 St Clair D,2 Mundo E,1 Muglia P,1 King N,1 Macciardi F,1 and Kennedy JL1 1 Clarke Division Centre for Addiction and Mental Health, Toronto, Canada 2 Department of Mental Health, University of Aberdeen, Scotland, UK Bipolar Disorder (BP) is a severe psychiatric disease, with a strong genetic component, that affects 1% of the population worldwide and is characterized by recurrent episodes of mania and depression. Brain Derived Neurotrophic Factor (BDNF) has been implicated in the pathogenesis of mood disorders, and the aim of this study was to test for the presence of linkage disequilibrium between two polymorphisms in the BDNF gene and BP in 283 nuclear families. Family based association test (FBAT) results for the dinucleotide repeat (GT)n polymorphism at position -1040 bp showed that allele A3 was preferentially transmitted to the affected individuals (Z ¼ 2.035 and P ¼ 0.042). FBAT results for the Val66Met SNP showed a significant association for allele G (Z ¼ 3.415 and P ¼ 0.00064). TDT haplotype analysis showed a significant result for the 3-G allele combination (P ¼ 0.000394), suggesting that a DNA variant in the vicinity of the BDNF locus confers susceptibility to BP. Given that there is no direct evidence for either of the polymorphisms we examined altering function, it is unlikely that the actual riskconferring allele is from these two sites. Rather, the causative site is likely nearby and in linkage disequilibrium with the 3-G haplotype that we have identified. Further association

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studies are being undertaken in order to study both polymorphisms in a Scottish population. P43 FAROESE PATIENTS WITH BIPOLAR AFFECTIVE DISORDER AND SCHIZOPHRENIA SHOW INCREASED HAPLOTYPE SHARING ON 18p11 Nyegaard M,1 Dahl HA,1 Hatting L,1 Wang A,2,3 Vang M,2 Mors O,4 Ewald H,4 and Kruse TA1 1 Department of Clinical Biochemistry and Genetics, Odense University Hospital, Denmark 2 Department of Psychiatry, National Hospital, Torshavn, Faroe Islands 3 Institute for Basic Psychiatric Research, Copenhagen University Hospital, Denmark 4 Institute of Basic Psychiatric Research, Psychiatric Hospital in Aarhus, Denmark Patients from isolated populations may be valuable in the mapping of complex traits, as the patients potentially share an identical disease mutation, inherited from a common founder. In this study, chromosome 18 was screened for susceptibility genes for bipolar affective disorder and schizophrenia using distsantly related patients and control individuals from the Faroe Island. Approximately 40 markers were analysed on 17 bipolar patients, 15 schizophrenia patients and 44 control individuals. Evidence of increased haplotype sharing were found on chromosome 18p11.31 (19–20 cM from pter) for bipolar affective disorder and on 18p11.2 (40–45 cM from pter) for both bipolar and schizophrenia. The shortest shared haplotype on 18p11was between D18S71 and D18S40. The 18p11 region, in particular, overlap with previous published candidate regions for bipolar disorder and schizophrenia. P44 PHENOTYPE CHARACTERISATION OF LARGE ANDALUSIAN KINDREDS WITH BIPOLAR AFFECTIVE DISORDER Diaz O,1 Rivas F,1 Auburger G,2 Ohlraun S,3 Illes F,4 Gay E,5 Sans S,5 Gonza´lez MJ,6 Gil S,7 Cabaleiro F,8 Cichon S,9 Propping P,10 Noethen MM,9 and Rietschel M3 1 Civil Hosp. Carlos Haya, Ma´laga, Spain 2 University of Frankfurt, Germany 3 ZIMH, Mannheim, Germany 4 University of Bonn, Germany 5 University Hospital Reina Sofı´a, Co´rdoba, Spain 6 Mental Health Care Centre Lucena, Co´rdoba, Spain 7 Mental Health Care Centre Montoro, Co´rdoba, Spain 8 Prov. Hosp., Jae´n, Spain 9 University of Antwerp, Belgium 10 University of Bonn, Germany In the catchment area of the psychiatric centres in Andalusia patients are systematically screened for the occurrence of bipolar disorder and are questioned about further affected

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relatives. So far, 77 multiplex families have been characterized including 923 individuals. Each individual was interviewed using the SADS. Life time diagnoses were made according to DSM-IV.31 families were recruited from Cordoba, 16 from Granada and 30 from Malaga. In average, 12 (SD 8.0) members were characterised per family. 192 persons had BPI, 61 BPII, 144 recurrent MD, 33 MD single episode, 1 schizophrenia and 53 other psychiatric disorders. On average, each family had 3.6 (SD 2.9) bipolar members (including BPI, II, nos), 2.8 (SD 2.6) otherwise affected (alcohol abuse, MD single episode, etc.) and 5.7 (SD 4.1) healthy members. Age at onset in patients with BPI was 23.78 years (SD 9.93), in patients with BPII 24.12 years (SD 14.18) and with recurrent MD 31.25 years (SD 13.86). The age of onset for BPI and recurrent MD did not differ significantly between the three towns Granada, Cordoba and Malaga. However, the age of onset for BPII was significantly higher in Cordoba (28.40/SD 18.85) than in Granada (18.00/ SD 8.72). Of all BPI persons 78 were male and 114 female; of all BPII 20 were male and 41 female and of all persons affected by recurrent MD, 36 were male and 108 female. These data show a larger susceptibility for unipolar and bipolar affective disorders in females. A genome-wide linkage scan is being conducted for 45 families. First results and the detailed structure and demographic description of these families will be presented. P45 EXPANDED RED PRODUCTS AND LOCI CONTAINING CAG/CTG REPEATS ON CHROMOSOME 17 (ERDA1) AND CHROMOSOME 18 (CTG18.1) IN TRANS-GENERATIONAL PAIRS WITH BIPOLAR AFFECTIVE DISORDER Oswald P,1 Souery D,1 Del-Favero J,2 Massat I,1 Lindblad K,3 Engstro¨m C,4 Van den Bossche D,2 Adolfsson R,4 Schalling M,3 Van Broeckhoven C,2 and Mendlewicz J1 1 Department of Psychiatry, University Clinics of Brussels, Erasme Hospital, Free University of Brussels, Belgium 2 Molecular Genetics Department, Flanders Interuniversity Institute for Biotechnology (VIB), University of Antwerp (UIA), Belgium 3 Neurogenetics Unit, Department of Molecular Medicine, Karolinska Hospital Stockholm, Sweden 4 Department of Psychiatry, University of Umea˚, Sweden The purpose of the present study was to further test if expanded CAG repeats detected by the Repeat Expansion Detection Method (RED) method in Bipolar Affective Disorder (BPAD) are correlated with ERDA1 (17q21.3) and/or CTG18.1 (18q21.1) loci expansions, and changes of phenotype severity in successive generations (anticipation). The sample was designed to analyse ERDA1 and CTG18.1 expansions in trans-generational pairs of affected individuals (parent-offspring pairs: G1 and G2). Clinical and genetic information was available on 95 two-generations pairs. We

found in our sample no patient carrying an expanded allele at the CTG18.1 locus. This observation is true for all individuals in G1 and G2. Using the conditional logistic regression, no statistical difference was observed between the two generations for ERDA1 alleles (w2 ¼ 0.2, P ¼ 0.65). These data do not support the correlation between expanded RED products (RED fragments >120) and expanded alleles at ERDA1 in trans-generational pairs with BPAD. We were not able to detect any correlation for CTG18.1. Earlier age at onset in offspring generations was also not associated with expanded RED products explained by expanded ERDA1 alleles. P46 ROLE OF POLYMORPHISMS IN THE ESTROGEN RECEPTOR ALPHA GENE IN PREMENSTRUAL DYSPHORIC DISORDER (PMDD) Roca CA,1 Harlow BL,2 Davis C,1 Schmidt PJ,1 Goldman D,3 and Rubinow DR1 1 Behavioral Endocrinology Branch, National Institute of Mental Health, Bethesda, Maryland 2 Obstetrics and Gynecology Epidemiology Center, Brigham and Women’s Hospital, Boston, Massachusetts 3 Laboratory of Neurogenetics, National Institute on Alcohol Abuse and Alcoholism, Bethesda, Maryland PMDD affects approximately 5% of women of reproductive age and is characterized by a combination of mood and behavioral symptoms during the luteal phase of the menstrual cycle. Population-based twin studies have estimated the heritability of this disorder to be between 50 and 60%. Genetic polymophisms of the ER alpha gene have been associated with several disorders known to be influenced by gonadal steroids including decreased bone density, infertility, and dementia. Previous studies by our group have demonstrated that women with PMDD are differentially sensitive to changes in gonadal steroids compared to women without a history of premenstrual symptoms. Therefore, we obtained genotypes for polymorphisms in the ER alpha gene. DNA for genetic studies was isolated from two groups of Caucasian PMDD patients (n ¼ 97) and controls (n ¼ 274). Patients met DSM IV criteria for PMDD and had the diagnosis confirmed by prospective ratings; controls exhibited no premenstrual symptoms on prospective ratings. The PvuII and XbaI polymorphisms of the ER alpha gene were examined. Statistical analysis of allele frequencies was performed by the MantelHaenszel test; geneotype frequencies were analyzed using the Pearson chi square test. PMDD patients did not differ from controls in either allele or genotype frequencies for the PvuII or XbaI polymorphisms. Although these data do not support a significant role for genetic variation in the ER alpha gene in PMDD vulnerability, polymorphisms in this gene could play a role in treatment response or may reveal an effect on vulnerability when tested across larger populations of patients.

Abstracts

P47 SYSTEMATIC TDT ANALYSIS IN A SUSCEPTIBILITY REGION FOR BIPOLAR AFFECTIVE DISORDER ON 8q24 Schumacher J,1 Kaneva R,1 Becker T,2 Richter C,1 Ohlraun S,3 Rietschel M,3 Cichon S,4 No¨then MM,4 and Propping P1 1 Institute of Human Genetics, University of Bonn, Germany 2 Institute of Medical Biometry, Informatics, and Epidemiology, University of Bonn, Germany 3 Central Institute of Mental Health, Mannheim, Germany 4 Deptartment of Medical Genetics, University of Antwerp, Belgium The genome wide screen of 75 families of German, Israeli and Italian origin with BPAD revealed a new susceptibility locus on 8q24 (Cichon et al., 2001). The STR marker D8S514 gave a two-point LOD score of 3.61 and a multipoint HLOD score of 3.01. A NPL score of 3.56 maximizied at the same location. In an attempt to further narrow down the positive linkage region we undertook a linkage disequilibrium study (LD) in a triad sample. In total, one hundred and nineteen triads of which the index cases were diagnosed BPAD (DSMIII-R) were selected for the Transmission Disequilibrium Test (TDT). Part of the triads (53) were extracted from the original genome screen sample, showing linkage to 8q. The remaining 66 triads were independent. In the first step of the analysis 8 polymorphic STR markers were selected from the linkage region, between D8S1823 and D8S1804, encompassing about 5 Mb. Single marker as well as two-marker haplotypes were tested for transmission disequilibrium. The haplotype analysis revealed two regions of interest. One lies exactly in the vicinity of marker D8S514, showing the peak in the LOD score analysis. A distortion in the transmission equilibrium was observed for certain haplotypes of markers D8S1726-D8S1826 (P ¼ 0.008) and D8S514-D8S1826 (P ¼ 0.035). The other region is more centromeric, between markers D8S1823 and D8S198. The largest allele of D8S1823 (234 bp) was preferentially transmited (34 transmissions and 16 non-transmissions, nominal P ¼ 0.01). The two-marker haplotype D8S1823-D8S198 (234-160 bp) was also preferentially transmitted (16 transmissions and 2 nontransmissions, nominal P ¼ 0.001). In the following, second step of our analysis new polymorphic markers were identified and will be genotyped to obtain a more precise picture of the distribution of linkage disequilibrium in the studied region on 8q24.

P48 ADMIXTURE ANALYSIS OF BIPOLAR ONSET IN A ROMANIAN SAMPLE Serbanescu M1 and Golmard JL2 1 Psychiatric Genetics Research Unit, Bucharest, Romania 2 Dept. Biostatistique et Informatique, INSERM U436, Paris, France

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Efforts are undertaken to validate onset age classes for bipolar (BP) disorder in order to improve the sensitivity of molecular genetic studies. Two methods are currently applied for determining onset classes: distribution analysis with histogram inspection and admixture analysis (Fleiss, 1972). Bellivier et al. (2001) applied the admixture analysis to the age-of-onset (AO) of BPI disorder suggesting the existence of three AO groups with different means; but the corresponding curves and the clinical profiles were highly overlaping; clinically, only the number of suicide attempts differentiated significantly the three groups. We also performed an admixture analysis (stochastic EM or SEM algorithm) on a first sample of BPI patients (N ¼ 177) and a second BPI sample (N ¼ 200) recruited from consecutive hospital admissions with the aim of checking the existence of the mixed distributions and AO means. Replication of AO groups with similar means and S. D. might lead to the determination of standard onset classes. The SEM algorithm found three classes in the 177 BPI sample. This model was better than the two class (P < 0.02). In the 200 BPI sample the four class solution was statistically the best but it made less clinical sense (one group had only 6.6% patients and two groups had very close means—21 years and 27 years. So, the three class solution was preferred. Graphically, the three classes were operlapping. The means and S. D. of the first two AO classes were strikingly similar to the values found in the sample of Bellivier et al. [2001]. In conclusion the admixture analysis is a useful mathematical tool for proving mixture of AO distributions; its results are sample dependent. However, because of providing overlapping classes, practical difficulties may arise when classifying individual cases. P49 AGE OF ONSET IN BIPOLAR I DISORDER: IMPACT OF FAMILY HISTORY Serbanescu M,1 No¨then MM,2 Propping P,3 Ohlraun S,4 and Rietschel M4 1 Psychiat Genet Res Unit, Bucharest, Romania 2 Dept Med Genet, University of Antwerp, Belgium 3 Inst Hum Genet, University of Bonn, Germany 4 Department of Psychiat, University of Bonn, Germany In our study, we investigated the effect of a family history of affective disorder on gender differences in age of onset (AO) of bipolar affective disorder. 256 BPI probands recruited from consecutive hospital admissions in Bucharest (N ¼ 200) and Bonn (N ¼ 56) were subdivided into sporadic cases (N ¼ 139) and cases with affected relatives (N ¼ 117). Families were classified as sporadic if the proband was the only affected individual in the proband’s and the two previous generations. A positive family history was defined through at least one affected individual in the parental or grandparental generation. Diagnoses were made according to DSM-IV. Differences in AO were investigated using t-tests and survival functions. In sporadic patients, AO was significantly

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later in female probands than in male probands (P ¼ 0.003). In patients with a family history of affective disorder a significantly younger AO was observed in female probands compared to male probands (P ¼ 0.02). The survival curves confirmed these differences (P ¼ 0.002). The female/male ratio was equal in either group. Our results differ from results previously suggested from unselected bipolar patient populations where no AO difference emerged between females and males [Gershon et al., 1982; Rice et al., 1987]. However, they are in accordance with the results from McMahon et al. [1994] who reported an earlier AO in females from families with two affected relatives.

P50 DOES THE SEX OF AFFECTED GRANDPARENTS INFLUENCE AGE AT ONSET IN BIPOLAR I DISORDER? Serbanescu M,1 No¨then MM,2 Propping P,3 and Rietschel M4 1 Psychiatric Genetics Research Unit, Bucharest, Romania 2 Dept. of Medical Genetics, University of Antwerp, Belgium 3 Institute of Human Genetics, University of Bonn, Germany 4 Department of Psychiatry, University of Bonn, Germany Anticipation has been reported in the transmission of bipolar disorder (BP) and it seems most prominent in parternal transmission while maternal transmission of disease is associated with reduced anticipation in offspring [GrigoroiuSerbanescu et al., 1995, 1997; Kornberg et al., 2000]. The underlying mechanism is unclear. Repeat expansion, imprinting and mitochondrial inheritance have been suggested as possible causes. To distinguish between these possible causes we investigated the effect of the sex of affected grandparents on age at onset (AO), AO correlation and anticipation in affected mother- and affected father-offspring-pairs. 113 unilineal families with BP I probands recruited from consecutive hospital admissions in Romania and Germany with one affected grandparent and an affected parent were analysed considering four lineages: grandfather1father1 proband (GF-F-P) (N ¼ 25); grandmother1father1proband (GM-F-P) (N ¼ 37); grandfather1 mother1proband (GF-M-P) (N ¼ 27); grandmother1 mother1proband (GM-M-P) (N ¼ 24). The highest parentoffspring correlation in AO (r ¼ þ .61, P ¼.02) and no significant anticipation in offspring was found in the GM-MP transmission; offspring from this group had the oldest AO. The GF-F-P group showed significant parent-offspring correlation, significant positive anticipation and the youngest AO in offspring. The groups GM-F-P and GF-M-P showed no parent-offspring correlation in AO and positive anticipation was observed only in GM-F-P group. In conclusion, our data do not suggest the presence of one single cause of the clinically observed phenomena of anticipation and parent of origin effect, instead they suggest a combination of causes.

P51 PARENTAL AGE AT CHILD’S BIRTH AND AGE OF ONSET IN BP I DISORDER Serbanescu M,1 Rietschel M,2 Noethen MM,3 Propping P,4 and Ohlraun S2 1 Psychiat Genet Res Unit, Bucharest, Romania 2 Department of Psychiatry, University of Bonn, Germany 3 Dept Med Genetics, University of Antwerp, Belgium 4 Inst Human Genetics, University of Bonn, Germany Recently a study by Malaspina et al. [2001] revived the interest in the influence of parental age at child’s birth (PAB) on psychiatric disorders. Previous studies showed influence of PAB on Alzheimer’s disease and schizophrenia though findings were not always consistent [Bojanowski and Gerylovova, 1967; Farrer et al., 1991; Bertranpetit and Fananas, 1993; Whalley et al., 2001]. The influence of PAB on the risk for bipolar disorder (BP) was tangentially examined by Malaspina et al. [2001] with a negative result. We examined the effect of PAB on the age of onset (AO) in 256 BPI probands recruited from consecutive hospital admissions (sporadic cases and cases with affected relatives) and 156 BPI probands from 62 multiply affected families. The patients, diagnosed according to DSM-IV were subdivided into early (25) probands. Results: Mean age of father (FA) and mother (MA) at proband’s birth did not differ in the early-onset vs. late-onset group in any family type. AO in probands was significantly and positively correlated with both FA and MA in the earlyonset groups of sporadic and multiply affected families. In general population families with affected relatives there was no correlation. In the late-onset groups the correlations were significant and negative for FA in all family types, except general population families with affected relatives; MA correlated significantly and negatively with AO only in multiply affected and in general population families with affected relatives but not in sporadic families. Cox models applied to the late-onset groups showed a significant impact on proband AO for both FA and MA in multiply affected families, only for FA in sporadic families, and only for MA in general population families with affected relatives. Conclusion: PAB influences AO in BP disorder but the importance of each parent depends on family type.

P52 GENE POLYMORPHISMS AND SUICIDAL BEHAVIOUR IN MOOD DISORDERS Lattuada E, Serretti A, Lorenzi C, Lilli R, Mandelli L, and Smeraldi E Department of Psychiatry, Vita-Salute University, San Raffaele Institute, Milano, Italy In this study we have evaluated a sample of 1282 consecutively hospitalised unipolar or bipolar patients, with or

Abstracts

without a lifetime history of suicidal behaviour (347 suicidal vs. 935 non-suicidal). The patients were divided in nonsuicidal or suicide attempters, based on a lifetime perspective. Despite the fact that we studied a large pool of patients in our study, we were not able to confirm the reported significant associations between a number of candidate genes (TPH, 5HTTLPR, 5-HT2A/C, TH, DRD4, GABRA1/3, CYP2D6a/b, MAOA, COMT, CLOCK, Gbeta3) and suicidal behavior. This was observed when considering both allele and genotype analyses. No correlation was found even when subdividing the sample according to sex, early onset, marital status, education, socioeconomic status, unipolar vs. bipolar diagnosis, presence of personality disorder, attempters vs. completers, violent vs. non-violent suicidal acts or family suicide history. The only trend found was between the 218C allele of TPH and violent attempters (w2 ¼ 5.33, P ¼ 0.02). Our results suggest that in our sample the candidate genes we analyzed have no major influence on suicidal behavior; selection criteria or ethnicity issues may explain the discrepancies with reports of positive associations.

P53 PHARMACOGENETICS IN MOOD DISORDERS: GENETIC PREDICTORS OF LITHIUM EFFICACY Serretti A, Lattuada E, Mandelli L, Lilli R, Lorenzi C, and Smeraldi E Department of Psychiatry, Vita-Salute University, San Raffaele Institute, Milano, Italy Lithium treatment is effective in mood disorders, but its efficacy ranges from complete prevention of affective episodes to no influence at all. Clinical predictors account for less than 50% of lithium prophylactic efficacy and it is probable that genetic factors play a substantial role. We investigated the possible association between the dopamine receptors D2, D3, D4, the serotonin receptors 2a, 2c, 1a, the upstream regulatory region of the serotonin transporter gene (5-HTTLPR) and the tryptophan hydroxylase (TPH) genes with the prophylactic efficacy of lithium in mood disorders. Two hundreds and one subjects affected by bipolar (n ¼ 167) and major depressive (n ¼ 34) disorder were followed prospectively for an average of 58.2 months and were typed using polymerase chain reaction technique. DRD2, DRD3, DRD4, 5HT2a, 5HT2c, 5HT1a variants were not associated with lithium outcome, while 5-HTTLPR and TPH variants were associated with lithium outcome (P ¼ 0.005 and P ¼ 0.046 respectively). Consideration of possible stratification effects such as gender, polarity or age at onset did not influence the observed results. We may therefore provisionally hypothesize that part of the variance of the prophylactic efficacy of lithium may be regulated by the overall activity of the serotoninergic system. The genetic prediction of lithium

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efficacy would be of great benefit for clinicians because a long time is needed in order to identify responders.

P54 GENETIC PREDISPOSITION OF ANTIDEPRESSANT DRUG RESPONSE Stassen HH,1 Dahmen N,2 Hell D,1 Nu¨rnberg P,3 Sander T,3 Toliat MR,3 and Szegedi A2 1 Psychiatric University Hospital Zurich, Switzerland 2 Department of Psychiatry, University of Mainz, Germany 3 Max-Delbruck-Center, Berlin, Germany Our recent analysis of the data of 2788 patients treated with 7 different antidepressants and placebo has demonstrated that the onset of improvement occurred in 70% to 80% of all responders within the first two weeks of treatment. In particular, onset of improvement (sustained 20% HAMD-17 baseline score reduction) occurred in the average patient around day-13, virtually independent of treatment modality, and the average patient responded to treatment (sustained 50% HAMD-17 baseline score reduction) around day-20, again virtually independent of treatment modality. All HAMD-17 items contributed to the score reduction at early stages of treatment. Differences in efficacy between active drugs and placebo were reflected only by the total number of responders but not by the time characteristics of response. Early improvement was found to be to a substantial part druginduced and highly predictive of later response: the more effective the antidepressant the higher its proportion of early improvers who later became treatment responders. Our current molecular-genetic study of 120 candidate genes relies upon oligogenic models with interactions in order to explain the between-subject variation with respect to the basic properties of the monoaminergic systems, the HPA-axis, drug metabolism, and the cytochrome P450 enzyme systems. Ethnic variation is controlled through a set of 18 polymorphic markers selected to evaluate the between-subject genetic similarity in terms of ‘‘biological ethnicity’’. Interest is mainly focused on the relationships between moleculargenetic properties and drug response characteristics, such as onset of action or premature withdrawal. Specifically, we determine the time characteristics of response for each individual patient by survival-analytical methods and apply multivariate pattern recognition techniques for identifying configurations of genes that relate to the response characteristics of antidepressants. The oligogenic model is identified through iterative optimization, using the maximum withingroup genetic similarity together with the maximum between-group dissimilarity as search criteria. Supported in part by a grant of the Swiss National Science Foundation (SNF 31-63769.00).

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P55 BRAIN DERIVED NEUROTROPHIC FACTOR POLYMORPHISMS AND CHILDHOOD ONSET DEPRESSION Strauss J,1 Barr CL,2 King N,1 Shaikh S,1 Kovacs M,3 and Kennedy JL1 1 Centre for Addiction and Mental Health, University of Toronto, Canada 2 The Toronto Western Hospital and the Hospital for Sick Children, University of Toronto, Canada 3 Western Psychiatric Institute and Clinic, University of Pittsburgh Medical Center Twin studies in youth have shown depressive symptoms to have significant heritability. Brain derived neurotrophic factor (BDNF) is a nerve growth factor that has an important role in neuronal proliferation, survival and plasticity. It has antidepressant-like effects at cellular and molecular levels in animals. The BDNF gene has been associated with mood disorder in adults. The hypothesis arising from this background is that genetic variants at the BDNF locus are associated with childhood onset major depressive disorder (COD). We genotyped two polymorphisms in 107 cases with childhood onset DSM-IV major depressive disorder and in 107 healthy controls individually matched for ethnicity and sex. The first was a GT dinucleotide repeat located 1040 bp upstream from the transcription initiation site; the second was a valine to methionine single nucleotide polymorphism (SNP) at amino acid position 66. The BDNF GT repeat was strongly associated with COD (w2 ¼ 16.5, d.f. ¼ 4, P ¼ 0.0025); with an odds ratio of 2.95, 95% CI ¼ [1.39–6.25], for the 168 bp allele. Alleles at the Val66Met SNP were not significantly associated with COD (w2 ¼ 3.14, d.f. ¼ 1, P ¼ 0.08), odds ratio ¼ 1.59, 95% CI ¼ [0.67–3.77]. A logistic regression model demonstrated that ethnicity was not a significant cofactor for COD (w2 ¼ 0.0, d.f. ¼ 1, P ¼ 0.96) while the GT repeat predicted COD (w2 ¼ 16.2, d.f. ¼ 4, P ¼ 0.0028). We conclude that the BDNF GT microsatellite is associated with COD. Sample stratification due to ethnicity does not appear to be contributing to the association. Given the problems with replication validity in genetic association studies, our findings should be considered preliminary. Nonetheless, the results support previous experiments that suggest BDNF is a neuroprotective factor relevant to depression.

P56 A GENOME-WIDE SCAN OF SMOKING FAILS TO FIND LINKAGE IN BIPOLAR DISORDER PEDIGREES Su J,1 Faraone S,1 and Tsuang M2 1 Department of Psychiatry, Harvard Medical School, Boston, Massachusetts 2 Harvard Institute of Psychiatric Epidemiology and Genetics, Boston, Massachusetts

Recent findings suggest that increased smoking in the mentally ill may have an underlying biological etiology. It has been hypothesized that nicotine normalizes sensory gating deficits in schizophrenic patients. Further, studies have linked regions of chromosomes where nicotinic receptor genes reside to schizophrenia (1p21.3, 8p21-22, 15q14). At an incidence of greater than 50%, smoking in bipolar disorder is also strikingly high. Although fewer studies have examined the relationship between smoking and bipolar disorder, some genetic studies of bipolar disorder have found linkage to 15q14, a region that contains the alpha 7 nicotinic receptor gene [Edenberg et al.,1997; Craddock et al., 1999; Turecki et al., 2000]. In this study, we investigate further the genetic etiology between bipolar disorder and smoking. We present a genome wide scan of 538 genotyped individuals in 97 families from the NIMH genetic initiative for bipolar disorder. To do this, we developed a quantitative trait for smoking status by using pack years, adjusting it by age, and transforming it to be normal. This smoking trait has a heritability of 30% (P ¼ .007). Using Genehunter, exact likelihoods of sharing 0, 1 or 2 alleles were calculated for each relative pair within each pedigree. These likelihoods were used in a multipoint variance components linkage analysis performed in SOLAR. Our results fail to show LOD scores greater than 2 (the highest LOD score was 1.25 on chromosome 21). Further investigation needs to be performed to determine the potential genetic etiology to smoking in bipolar subjects.

P57 THE COMT (VAL/MET) GENE VARIANT AFFECTS SHORT-TERM RESPONSE TO MIRTAZAPINE TREATMENT IN MAJOR DEPRESSION Tadic´ A,1 Mu¨ller MJ,1 Dahmen N,1 Rujescu D,2 Giegling I,2 Stassen HH,3 and Szegedi A1 1 Department of Psychiatry, University of Mainz, Germany 2 Department of Psychiatry, University of Munich, Germany 3 Psychiatric University Hospital Zurich, Research Department, Zurich, Switzerland The catechol-O-methyltransferase (COMT) is a major enzyme in the degradation of norepinephrine. A three-tofourfold difference of enzyme activity was found to be associated with a common G to A gene variant located in the COMT gene (22q11). This transition at codon 108/158 yields a valine to methionine substitution, which was found to be responsible for the low-active enzyme form (COMT*LL). We tested the hypothesis that allelic variation of COMT could be related to antidepressant response to mirtazapine, an antagonist of 2-, 5-HT2 and 5-HT3 receptors, and paroxetine, a SSRI. Ninety-seven outpatients with major depression were randomly assigned to treatment with either

Abstracts

mirtazapine (dose range 30–45 mg/d) or paroxetine (20– 40 mg/d). Depression severity was assessed at baseline (day 0), on day 7, 14, 21, 28, and 42 using the HAMD-17. For determination of allelic variation a PCR-based technique was used. Data were analyzed with two-way repeated measures and one-way analyses of variance. In the mirtazapine-treated group, homozygotes for the high-activity enzyme form (COMT*HH) and heterozygotes (COMT*HL) showed an overall better response (P ¼ 0.044 and P ¼ 0.01, respectively) than COMT*LL patients. Detailed analyses revealed that COMT*HH and COMT*HL patients had a significantly (P 450 families, including >550 sibling pairs and anticipate >600 sibling pairs by the close of data collection. Siblings are evaluated for lifetime alcohol dependence by clinically trained interviewers using a modified version of the SSAGA and for comorbid disorders using modified modules from the SCID-R. Based on cases already data-entered, affected participants are 64.4% male with a mean age of 41.7 years (SD ¼ 9.7). Affected individuals have severe histories; 98% meet ICD-10 criteria for alcohol dependence (mean # criteria ¼ 5.1 of 6), and 75% reported alcoholism treatment. Average consumption during the worst episode was 19.6 drinks per day (SD ¼ 13.1), and mean single-day maximum consumption was 38.1 drinks (SD ¼ 18.8). Mean ages for drinking milestones were: first drink ¼ 15.6 years (SD ¼ 4.3); first time intoxicated ¼ 17.3 years (SD ¼ 5.5); and onset of regular drinking ¼ 18.1 years (SD ¼ 5.2). Males and females did not differ in age at interview, but males tended to have earlier ages for drinking milestones and symptom onsets and consumed greater amounts. Psychiatric comorbidity is substantial, with the majority of individuals having at least one other disorder, including: conduct disorder and/or antisocial personality 34%, nicotine dependence 70%, other drug dependence 28%, and major depression (excluding cases secondary to alcoholism) 37%. Sib-pair correlations for comorbid disorders (r.30), suggest there is familiality of alcoholism subtypes defined by comorbidity. DNA has been obtained from >99% of affected siblings and 25% of living parents. Molecular genetic work planned for 2003 includes a 10 cM genome scan and case-control analyses of candidate genes using community controls from Ireland.

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P80 METABOTROPIC GLUTAMATE RECEPTOR POLYMORPHISMS (MGLU7 AND 8) AND ALCOHOL WITHDRAWAL Preuss UW, Koller G, Bahlmann M, Zill P, Soyka M and Bondy B Department of Psychiatry, Ludwig-MaximiliansUniversitaet, Mu¨nchen, Germany Glutamatergic neurotransmission is upregulated in chronic ethanol intoxication. This may cause a hyperexitable state during alcohol withdrawal that results in seizures and delirium tremens. The aim of our study was to evaluate the association between a history of alcohol withdrawal-induced seizures and delirium tremens and mGlurR7 (Tyr433Phe) and mGlurR8 (C2756T) metabotropic Glutamate receptor polymorphisms. 182 patients meeting DSMIV alcohol dependence criteria and 117 controls, both of German decent, were enrolled. MgluR7 and mGluR8 Polymorphisms were determined using PCR (Polymerase Chain Reaction) of lymphocyte DNA. History of alcohol withdrawal-induced delirium tremens and seizures were obtained using the SSAGA (Semi-Structured Assessment of Genetics in Alcoholism) and data were crosschecked with inpatients’ clinical files. A weak association between the polymorphism of the mGluR7 and a history of alcohol withdrawal-induced seizures was found. The results of this study may shed a light on the potential influence of glutamate receptor polymorphisms on alcohol-withdrawal related phenotypes.

P81 FAMILIALITY OF ALCOHOL ABUSE AND DEPENDENCY AT AGE 14: A FINNISH TWIN-FAMILY STUDY Rose RJ,1,2 Dick DM,2 Viken RJ,1 Nurnberger Jr JI,3 Kaprio J,4 and Pulkkinen L5 1 Department of Psychology, Indiana University, Bloomington, USA 2 Department of Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis 3 Institute of Psychiatric Research, Indiana University School of Medicine, Indianapolis 4 Department of Public Health, University of Helsinki, Finland 5 Department of Psychology, University of Jyva¨skyla¨, Finland We report analyses of symptoms of alcohol abuse/dependency in a population-based sample of 1, 550 individual twins interviewed at age 14 with the adolescent version of Semi-Structured Assessment for Genetics of Alcoholism (SSAGA). The twins represent a sample enriched for alcoholism-risk, and they and their parents completed baseline questionnaires, the parental version of which included an 11-item alcoholism screen. Prevalence of diagnosed alco-

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holism at age 14 is very low, as expected, with only 1% of individual twins meeting DSM criteria for alcohol dependence and 3% diagnosed with alcohol abuse. One or more symptoms for nine criteria for alcohol abuse were reported by 12.5%, yielding correlations approximating 0.6 across sex and zygosity; similarly, pairwise concordance for SSAGA symptoms of alcohol abuse are equivalent (55% and 58%) in MZ and same-sex DZ twin pairs—evidence of substantial familiality of adolescent alcohol symptoms, but zero heritability at this age. Correlations of symptom tallies for twins at age 14 with their parents’ alcoholism screening scores and with teacher ratings of their behavior problems (inattention, impulsivity and aggression) made when twins were age 12 are modest, but significant. Support: NIAAA (grants 09203 and 07611) and the Academy of Finland.

P82 SEROTONIN GENE POLYMORPHISMS AND OPIATE ADDICTION Sa´iz PA,1 Alvarez C,2 Morales B,3 Coto E,3 Alvarez V,3 G-Portilla MP,1 Carren˜o E,2 San Narciso G,2 and Bobes J1 1 Deparment of Psychiatry, University of Oviedo, Spain 2 Clı´nica Asturias, Gijo´n, Spain 3 Laboratory of Molecular Genetics. Hospital Central de Asturias, Spain To investigate the possible association between four serotonin gene polymorphisms [T102C, A-1438G, VNTR (5HTT), 5-HTTLPR] and opiate addiction. Patients and Methods: We genotyped 77 opiate addicts (DSM-IV criteria) [mean age: 31.44 (6.34), 89.6% males] and 111 healthy volunteers (blood donors) [mean age: 43.59 (11.19), 75.7% males] from Asturias (Northern Spain). Polymorphisms were determined after PCR amplification followed by digestion with restriction enzymes and electrophoresis on an agarose gel. Results: 5-HT2A polymorphisms- both 5-HT2A polymorphisms (T102C and A-1438G) are in complete linkage desequilibrium in our population. T102C or A-1438G (opiate addicts vs. controls): TT or AA: 28.6%, 18.0%; TC or AG: 46.8%, 54.1%; CC or GG: 24.7%, 27.9% (P ¼ .232). Serotonin transporter polymorphisms-VNTR (5-HTT) (opiate addicts vs. controls): 12rep12rep: 49.4%, 39.6%; 12rep10rep: 33.8%, 31.5%; 12rep9rep: 2.6%, 0.9%; 10rep10rep: 13.0%, 27.0%; 10rep9rep: 1.3%, 0.9% (P ¼ .188).5HTTLPR (opiate addicts vs. controls): LL: 18.2%, 32.4%; LS: 55.8%, 47.7%; SS: 26.0%, 19.8% (P ¼ .090). VNTR (5-HTT) 12rep allele was more frequent in opiate addicts: 67.5% vs. 55.9% (OR: 1.64, 95%CI ¼ 1.07–2.53; P ¼ .024]. Polymorphic variations in the VNTR in the serotonin transporter gene might influence susceptibility to opiate addiction. However, larger samples are necessary to confirm or reject the current data.

P83 ANALYSIS OF GENETIC VARIATIONS OF PROTEIN TYROSINE KINASE ‘FYN’ AND THEIR ASSOCIATION WITH ALCOHOL DEPENDENCE Schumann G,1 Dahmen N,2 Rujescu D,3 Wieman S,4 Wellek S,5 Mu¨ller A,1 Kissling C,1 Lascorz J,1 Anghelescu I,2 Klawe C,2 Poustka A,4 Spanagel R,6 Mann K,7 and Szegedi A2 1 Department of Psychiatry, Molecular Genetics Laboratory, Central Institute of Mental Health (CIMH), Mannheim, Germany 2 Department of Psychiatry and Psychotherapy, University of Mainz, Germany 3 Molecular Neurobiology, Department of Psychiatry and Psychotherapy, University of Munich, Germany 4 Mol. Genome Analysis, German Cancer Research Center, Heidelberg, Germany 5 Department of Biostatistics, CIMH, Mannheim, Germany 6 Department of Psychopharmacology, CIMH, Mannheim, Germany 7 Department of Addictive Behavior and Addiction Medicine, CIMH, Mannheim, Germany Genetic studies on alcohol dependence revealed heritability estimates ranging between 50–60%. PTK fyn is an intracellular src-like kinase, which is expressed in the brain. Fyn knockout mice show increased alcohol sensitivity and lack of tolerance to the effects of ethanol due to a reduction of fyndependent phosphorylation of the NMDA receptor subunits 2A and 2B, leading to a loss of ethanol-induced inhibition of NMDA-mediated excitatory postsynaptic potentials. NMDA-mediated glutamatergic neurotransmission in alcohol dependence has been linked to withdrawal phenomena. Increased alcohol sensitivity has been shown to be negatively correlated with alcohol dependence. Therefore, we were interested to investigate a possible association of PTK ‘fyn’ genetic variations and alcohol dependence in a European cohort. We analysed 6 single nucleotide polymorphisms (SNP’s) from the exons and the 50 -UTR of the PTK ‘fyn’ gene. 3 PTK fyn SNP‘s derived from a public database were not informative. The remaining 3 SNP’s were genotyped in a cohort of 250 patients with alcohol dependence according to DSM IV criteria and 200 unrelated control subjects. We will present the results of our association study, including an analysis of association of PTK-fyn genotype with phenotypes presumably carrying a higher genetic load, such as positive family history, early onset of disease (150 and 201 controls with mean IQ of 100), followed by three replication stages: 2) DNA pooling with our within family sample of 196 parent-child trios for offspring with IQ >160, 3) case-control pooling with 7-year-old children who are high versus low ‘g’ and 4) DZ twins phenotypically discordant for ‘g’. Use of functionally significant SNPs within genes will enable more direct studies of gene mechanisms once significant associations have been identified, without the need for further fine-mapping work. P99 VALIDATION OF ORAL TRADITIONS REGARDING ORIGIN AND SEARCH OF GENES FOR PSYCHOTIC DISORDERS IN A GENETIC ISOLATE FROM ISRAEL Kohn Y,1 Ben Zeev E,2 Filon D,3 Oppenheim A,3 Danilovitz E,4 Karni O,1 Kanyas K,1 Turetsky N,1 Korner M,5 and Lerer B1 1 Biological Psychiatry Laboratory, Hadassah University Hospital, Israel 2 The Truman Institute for the Advancement of Peace, Hebrew University, Israel 3 Department of Hematology, Hebrew University-Hadassah Medical School, Israel 4 Eitanim Mental Health Center 5 Hebrew University Genome Strategic Resource Laboratory, Jerusalem, Israel

‘‘QX’’ is an Arab village in Israel with a population of 5,000. The oral tradition in the village is that its founders were immigrants from the Caucasus or from Yemen who settled there about 500 years ago. Current inhabitants of the village are descendents of one man who lived 250 years ago. Since then most people marry within the village. Psychiatric morbidity in QX is considerable. We have recruited 51 patients with major psychiatric disorders in QX as well as 43 firstdegree relatives. Best estimate diagnoses are made according to DSM-IV/RDC based on SADS-L interviews and medical records. Genotypes for 350 microsatellite markers were determined, spread with an average coverage of 4–5 cM on 9 chromosomes (1, 5, 6, 8, 10, 13, 15, 18, 22). These chromosomes were selected because of previous linkage findings in psychotic patients. Eight Y chromosome markers were also studied in 33 men from the sample who are not first-degree relatives. 28 of them (85%) have exactly the same Y chromosome haplotype. 4 (12%) have one or two different alleles, which may represent new mutations. The shared Y chromosome haplotype is relatively common among Arabs in Northern Israel and Yemen. These results clearly validate the oral tradition regarding the common paternal origin of the village population as well as the tradition of a Yemenite origin. They also support the assumption that shared mutations causing psychotic disorders and introduced by a common founder, are more likely to be found in this unique population. We are searching for identity by descent haplotype sharing between affected individuals from this isolate as evidence for the localization of the presumed mutations. P100 NATIONAL-ETHNIC PECULIARITIES OF Y-CHROMOSOMES POLYMORPHISM AND LONGEVITY Kuznetsov VV and Gurianova NV The Ukrainian Geriatric Rehabilitation Center, Institute of Gerontology, Kiev, Ukraine Y-chromosome polymorphism, ethnic study, aging. This study was undertaken to identify Y-chromosome variants related to ethnic longevity in three ethnic groups. The Ychromosome (Y/G index) was shown to be longer in longliving inhabitants of Abkhasia and Azerbaijan compared to those of the Ukrainian region (1.16  0.04, 1.08  0.03 and 0.99  0, respectively, P < 0.05). The ethnic differences were more pronounced in the middle-aged than in long-living persons. There were no significant differences with regard to the relative size of the C-heterochromatin block on the Ychromosome, that constituted 65.39  2.56% in Azerbaijanians, 57.93  1.19% in Abkhasians and 60.49  1.65% in Ukrainians. On the other hand, the ethic differences in C-heterochromatin size were more pronounced in the middle-aged people (70.51  1.81% in Azerbaijanians). The C-heterochromatin size was smaller in Abhasians and Ukrainians: 51.28  2.93% (P < 0.05) and 45.37  1.36%

Abstracts

(P < 0.05), respectively. Our data indicate the absence of real ethnic differences in the Y-chromosome length and the Cheterochromatin block size along with the expressed differences of the Y-chromosome polymorphism in longlived from different regions. Ethnically, the old people of Abkhasia and Azerbaijan displayed the centenarian-like characteristics of Y-chromosome and of C-heterochromatin size. An assumption has been made that the Y-chromosome polymorphism variants are cytogenic variants of not only an individual but of the ethnic long-living individuals as well. P101 POPULATION STUDY OF POLYMORPHISMS IN THE SEROTONIN PATHWAY GENES IN A LARGE EUROPEAN SAMPLE: RESULTS FROM THE EUROPEAN COLLABORATIVE PROJECT ON AFFECTIVE DISORDERS Linotte S,1 Souery D,1 Oswald P,1 Massat I,1 Dupont S,2 Del-Favero J,3 Van Broeckhoven C,3 and Mendlewicz J1 1 Department of Psychiatry, Erasme Hospital, University of Brussels (ULB), Belgium 2 Biodiversity Research Centre, Catholic University of Leuven (UCL), Louvain-la-Neuve, Belgium 3 Department of Molecular Genetics, University of Antwerp (UIA), Belgium Serotonin (5-HT) plays a key role in the regulation of behaviour and in mood disorders. The aim of this study is to investigate allele and genotype frequency variability of different polymorphisms in the serotoninergic pathway genes (HTT, HTR2c, HTR2a) among 9 European centres of normal subjects. All subjects were genotyped within the framework of the Biomedical European Multicenter Collaborative Program (BIOMED 1-Grant CT 92-1217): European Collaborative Project on Affective Disorders (ECPAD). These polymorphisms are in Hardy-Weinberg equilibrium. Significant differences were observed between centers for allelic and genotypic frequencies. This was revealed by an original use of clustering method and cosinus distance. Trees were built and significant difference (P < 0.01) was observed between centers group. Concerning the overall HTT sample of 828 subjects, we found an allelic and genotypic variability between 3 groups of centers (P < 0.01), Milan (M), Helsinki (H), and the last group composed by Edinburgh (E), Sofia (S), Brussels (B), Jerusalem (J) and Munich (Mu). We found a significant variability (P < 0.01) in the HTR2c sample of 499 subjects. 4 groups are distinguished: M-J; H-B; E-S-Zagreb and finally Athens. No significant differences were observed for HTR2a. We can conclude that there is a great variability in European centers. These results confirm the need to take into account the stratification bias in association studies. Principal investigators: M. Ackenheil (Munich), R. Adolfsson (Umea), H. Aschauer (Vienna), D. Blackwood (Edinburgh), H. Dam (Copenhagen), R. Kaneva and V. Milanova (Sofia), B. Lerer

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(Jerusalem), L. Oruc (Zagreb), G. N. Papadimitriou and D. Dikeos (Athens), L. Peltonen (Helsinki), F. Macciardi and A. Serretti (Milan), L. Staner (Luxemburg), J. Mendlewicz (Brussels), C. Van Broeckhoven (Antwerpen). P102 COMPUTER-BASED PHENOTYPE-CHARACTERIZATION FOR MOLECULARGENETIC AND PHARMACOGENETIC STUDIES IN PSYCHIATRY Ohlraun S,1 Fangerau H,2 Schulze TG,2 Mueller DJ,2 Illes F,2 Widdern VO,2 Maier W,2 and Rietschel M1,2 1 Central Institute of Mental Health, Mannheim, Germany 2 Department of Psychiatry, University of Bonn, Germany The aetiology of psychiatric disorders such as schizophrenia and bipolar disorders is complex. Genetic factors account for 50–60% of the total variance. Furthermore, genetic factors influence response to medication. To identify disposition genes linkage and/or association studies have to be carried out. For these studies large sample sizes are required as the effect of single variants is limited. It is therefore necessary to collect samples in different clinical centres to enlarge the sample size. A serious problem of such multi-center studies is the heterogeneity of the phenotype characterisation. Homogeneous phenotypes however are a prerequisite for molecular genetic studies. We developed a questionnaire consisting of validated interviews for assessing life-time symptomatology and DSMI-V diagnoses. This interview has been translated into different languages. Based on these paper versions of the questionnaire, we generated a computer program for processing more than 2000 items per patient. These items are labelled and coded in the same way, regardless of language. Thus, the use of the computer program allows the homogeneous phenotype characterisation by the different study sites. Furthermore it allows easy data transfer between the sites and offers the possibility for interviewers to validate their colleagues diagnoses even if they do not speak the same language. We have been using the interview and its computer-version successfully in different European, Asian and Latin American cooperating clinical centres. Beside the poster presentation I would like to give a practical demonstration of the application of our diagnostic database. P103 POPULATION STUDY OF POLYMORPHISMS IN THE DOPAMINE PATHWAY GENES IN A LARGE EUROPEAN SAMPLE: RESULTS FROM THE EUROPEAN COLLABORATIVE PROJECT ON AFFECTIVE DISORDERS Oswald P,1 Souery D,1 Linotte S,1 Massat I,1 Dupont S,3 Del-Favero J,2 Van Broeckhoven C,2 and Mendlewicz J1 1 Erasme Hospital, Free University of Brussels, Belgium 2 Flanders Interuniversity Institute for Biotechnology, University of Antwerp, Belgium 3 Biodiversity Research Centre, Catholic University of Leuven, Belgium

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We investigated allele and genotype frequency variability of different polymorphisms in Dopamine D2, D3, D4 receptors genes (DRD2, DRD3 and DRD4) and tyrosine hydroxylase (TH) gene among 13 European samples of normal subjects. All subjects were genotyped within the framework of the Biomedical European Multicenter Collaborative Program: European Collaborative Project on Affective Disorders. DRD2 polymorphism was not in Hardy-Weinberg equilibrium, due to disequilibrium in Jerusalem and Edinburgh samples but the equilibrium was respected when excluding the 2 samples. DRD3, DRD4 and TH gene were in HardyWeinberg equilibrium. We used the clustering method and the distance cosinus to differentiate population groups regarding allele and genotype frequencies and to build biogeographical trees. Concerning the overall DRD2 sample of 497 subjects, we found a high allelic and genotypic variability between 3 groups (P < 0.01): 1) Jerusalem 2) Vienna 3) remaining 11 samples. In the DRD3 sample of 474 subjects, 3 groups were identified (P < 0.01): 1) Jerusalem, Munich, Copenhagen 2) Vienna, Edinburgh 3) remaining 5 samples. The variability in the DRD4 sample of 240 subjects was not significant. In the TH group of 528 subjects, we found a high variability (P < 0.01) between 4 groups: 1) Jerusalem 2) Helsinki 3) Brussels, Sofia, Zagreb, Munich 4) remaining 7 samples. These findings are of importance for multicenter studies and imply population stratification before analysing gene polymorphisms from samples of patients and controls from different ethno-geographical origins. Principal investigators: M. Ackenheil (Munich), R. Adolfsson (Umea), H. Aschauer (Vienna), D. Blackwood (Edinburgh), H. Dam (Copenhagen), R. Kaneva and V. Milanova (Sofia), B. Lerer (Jerusalem), L. Oruc (Zagreb), G. N. Papadimitriou and D. Dikeos (Athens), L. Peltonen (Helsinki), F. Macciardi and A. Serretti (Milan), L. Staner (Luxemburg), J. Mendlewicz (Brussels), C. Van Broekhoven (Antwerpen).

P104 INVESTIGATION ON BIPOLAR DISORDER IN A SARDINIAN SMALL VILLAGE: A FOUNDER POPULATION APPROACH Severino G, Saba G, Serio S, Ardau R, Oi A, and Del Zompo M Department of Neurosciences ‘B. B. Brodie’, University of Cagliari, Italy Our study presents the clinical characteristics and genealogical relationships in a sample of 14 apparently unrelated bipolar patients coming from a relatively isolated small Sardinian village. Following plague and famine at the end of 17th century the population size of this community decreased to about 500, and then increased to about 1600 at the end of 19th century. The major growth of this population occurred from 1921 to 1961 (14.7 per year) as a result of demographic

transition. With the help of church demographic records lineage were traced back as far as possible to determine a common ancestor and to evaluate the shortest possible genealogical distance between the pairs of the patients’ parents. Clinical diagnosis was made according to Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). A blood sample was drawn from each proband and from 18 subjects recruited as healthy controls. Genealogical results show that at least one of each patient’s parents is related in one or more ways to the other patients’ parents. All affected subjects have common ancestors born before 1643. The average number of generations relating two patients was 5.2. Our bipolar sample may be useful for genome-wide scan searching for shared chromosomal segments and to evaluate the founder effect in our Sardinian sub-population.

Poster Session 6: Candidate Genes P105 FURTHER TDT ANALYSES TESTING THE ASSOCIATON OF G PROTEIN RECEPTOR KINASE-3 (GRK3) WITH BIPOLAR DISORDER Barrett TB, Alexander M, Schork NJ, and Kelsoe JR Department of Psychiatry, University of California at San Diego, La Jolla, California In a genome-wide linkage survey we have previously shown evidence indicating chromosome 22q12 contains a susceptibility locus for bipolar disorder (BPD). Two independent family sets gave lod scores of 2.19 and 2.72 at or near marker D22S419 which lies 20 kb centromeric to the gene G protein receptor kinase-3 (GRK3). GRK3 is an excellent candidate susceptibility gene for BPD since GRKs play key roles in the homologous desensitization of G protein-coupled receptor signaling. In particular, GRK3 has been shown to desensitize CRF1 and Dopamine D1 receptors. GRK3 is expressed in many parts of the limbic system. We reported that in the rat GRK3 expression increased 14-fold in prefrontal cortex 24 hr after amphetamine injection suggesting GRK3 plays an important role in the brain’s homeostatic response to dopamine. To identify mutations in GRK3 we sequenced the putative promoter region, exons, and intron flanking each exon, in 14 individuals with BPD. We found six variants in the 50 UTR and promoter region, but no coding or obvious splice variants. Transmission disequilibrium data from two triad sets indicates one of these variants is associated with BPD. In 329 northern European Caucasian triads the transmission to non-transmission ratio was 26: 7.7, w2 ¼ 9.6, P ¼ 0.0019. We are genotyping additional variants newly identified by us as well as ones obtained from available databases. These span the gene and will be used to map LD through the region and to identify additional haplotypes associated with disease.

Abstracts

P106 NEUROLIGINS DISPLAY SEXUAL DIMORPHIC EXPRESSION IN THE HUMAN BRAIN Jamain S,1 Quach S,1 Betancur C,2 Leboyer M,2,3 Gillberg C,4,5 and Bourgeron T1 1 INSERM E021, Institut Pasteur, Paris, France 2 INSERM U513, Cre´teil, France 3 Hoˆpital Albert Chenevier et Henri Mondor, Assistance Publique-Hoˆpitaux de Paris, Cre´teil, France 4 Department of Child and Adolescent Psychiatry, Go¨teborg University, Sweden 5 Saint George’s Hospital Medical School, London, UK Synaptogenesis is considered as the final step in the development of the central nervous system. Among the genes involved in this process, cell adhesion molecules, such as neuroligins, are crucial factors for the identification of the appropriate partner cell and the forming of functional synapses. Here we describe the complete human neuroligin (HNL) family, including two members on the sex chromosomes absent in the mouse and the rat. HNL1-3, which are orthologues to rat neuroligin RNL1-3, are localised on chromosomes 3q26, 17p13, and Xq13, respectively. In addition, two members are present on the sex chromosomes with HNL4 localised on Xp22.3, and HNL5 localised on Yq11.22. Both HNL4/5 genes started to diverge during primate evolution between 30–50 million years ago. Whereas almost all the Y copies which have diverged at the same period turned into non-functional pseudogenes, the Y-linked HNL5 is one of the most conserved genes among X- and Y- homologues. Expression studies have shown that all HNLs have alternative transcripts and are present in all regions of the brain. As expected, HNL5 is not expressed in the female brain whereas HNL4 is. HNL3 and HNL4 are localised in regions of the X chromosome previously shown to be in linkage or deleted in subjects with schizophrenia or autism. Therefore, we suggest that the sexual dimorphism of HNL3-5 may influence the process of synaptogenesis and consequently may confer male predisposition to psychiatric diseases such as autism. P107 A CONFIRMATION OF THE ASSOCIATION BETWEEN 5HT1D BETA RECEPTOR GENE AND OBSESSIVE COMPULSIVE DISORDER SUBTYPE DEFINED BY GENDER RATHER THAN REPETITIVE BEHAVIORS Camarena B, Cruz C, and Nicolini H Dept. Gene´tica Psiquia´trica, Instituto Nacional de Psiquiatrı´a Ramo´n de la Fuente, Col. San Lorenzo Huipulco, Me´xico D, Me´xico The etiology of OCD is unknown, but data from pharmacological studies have supported the involvement of the serotoninergic system. Recent studies have shown that sumatriptan, a selective ligand of the serotonin 5-HT1Db autoreceptor, modifies OCD symptoms. Interestingly, it was reported linkage disequilibrium between G variant of the

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5-HT1Db receptor gene and OCD (Mundo et al., 2000). We thus analysed the G861C polymorphism of the 5-HT1Db receptor gene in a sample of 45 trios, plus five additional families with an affected sib-pair were included. TDT analysis did not find a preferential transmission of allele G (w2 TDT ¼ 2.08, P ¼ 0.149) in the total sample. TDT analysis by gender showed a preferential transmission of allele G in the OCD males (w2 TDT ¼ 4.48, P ¼ 0.03). In contrast, there was no statistical evidence of linkage disequilibrium between OCD females and 5HT1D beta (w2 TDT ¼ 0.043, P ¼ 0.835). Additionally, we analyzed the severity of repetitive behaviors, as measured by YBOCS-compulsion scores. TDT analysis did not show linkage disequilibrium between repetitive behaviors and allele G. Molecular studies have shown gender-related differences involved in OCD [Karayiorgou et al., 1999; Camarena et al., 2001]. Our findings may provide a sexually dimorphic effect of the 5-HT1Db gene in male probands. In addition, a correlation was reported between repetitive behaviors in male autistic patients with higher 5-HT1D sensitivity. Therefore, it is possible that the differences reported are a gender effect rather than repetitive behaviors. However, analysis of alternative phenotypes in larger samples of informative parents using strategies such as TDT are needed to prove the presence of a possible sexually dimorphic effect of the 5-HT1D beta gene in OCD. P108 PHARMACOGENETIC PREDICTION OF OLANZAPINE RESPONSE Clark D,1 Arranz MJ,1 Arrondo J,2 Beperet M,2 Lai T,1 Staddon S,1 Mancama D,1 Parsons M,1 Villavicencio R,1 Mata I,1,2 and Kerwin RW1 1 Clinical Neuropharmacology, Institute of Psychiatry, London, UK 2 Fundacion Argibide, Pamplona, Navarra, Spain In a previous study we reported that response to the atypical antipsychotic clozapine could be predicted using a combination of polymorphisms in the receptors targeted by the drug [Arranz et al., 2000]. Similar prediction tests could be developed for other drugs based on their pharmacological profile. Olanzapine is an atypical multitarget drug which displays high affinities for serotonergic, histaminic, muscarinic and adrenergic receptors similar to those showed by clozapine. However, olanzapine displays a higher affinity for dopaminergic type 3 (D3) receptors than clozapine. We have investigated polymorphisms in the systems targeted by olanzapine in a sample of 92 patients treated with olanzapine from Navarra (Northern Spain). Clinical response was assessed prospectively after at least 3 months of treatment using the PANSS and GAS scales. Preliminary results showed that a combination of polymorphisms in the genes coding for 5HT2C (VNTR, Cys23Ser, -759-C/T, -995-G/A), 5-HT2A (His452Tyr), D3 (Ser9Gly, -205-A/G) and 5-HTT (VNTR and LPR) can be used to predict treatment response (PPV ¼ 76%, NPV ¼ 79%, Sensitivity ¼ 82%, Specificity ¼

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72%, P ¼ 0.07). The sample is being extended to confirm this finding. If replicated, these results could form the basis of a pharmacogenetic prediction test for olanzapine response. P109 A CASE-CONTROL ASSOCIATION STUDY OF SUICIDE ATTEMPTS IN SOUTH AFRICAN SUBJECTS WITH AFFECTIVE MOOD DISORDERS Cupido C-L,1 Bardien S,1 Pietersen E,1 Komaravalli P,1 Kible D,2 and Ramesar R1 1 Division of Human Genetics, Faculty of Health Sciences, University of Cape Town Medical School, Observatory, South Africa 2 Department of Psychiatry and Mental Health, Division of Education Centre, Valkenberg Hospital, Observatory, Cape Town, South Africa Over 90% of suicide victims suffer a significant psychiatric illness, predominantly depression and bipolar manic depression. Several lines of evidence suggest altered serotonergic neurotransmission involved in the biological susceptibility of suicide. In this case-control study, we investigated eight components of the dopaminergic and serotonergic pathways viz. the DRD2, DRD3, DRD4, DAT, COMT, SERT, TPH and 5HTR2A genes. South African individuals meeting DSM-IV criteria for an affective mood disorder, with a history of suicide attempts, were selected (27 Caucasian and 19 mixed ancestry subjects) and compared with control samples from the background population (100 Caucasian and 60 mixed ancestry). We report an association between candidate genes in the dopaminergic pathway and attempted suicide. Significant differences in allele (w2 ¼ 8.707, df ¼ 2, P ¼ 0.013) and genotype (w2 ¼ 5.976, df ¼ 2, P ¼ 0.05) distributions for the DRD4 48 bp VNTR polymorphism were found between Caucasian cases and controls. The 4/4-repeat genotype and the 4-repeat allele were significantly less frequently observed in individuals with mood disorders who had attempted suicide, than in the background controls. Moreover, when the subjects were stratified for bipolar I disorder, an association was observed between the Caucasian cases and the COMT Val108Met polymorphism (w2 ¼ 7.602, df ¼ 2, P ¼ 0.022). The A/A (Met/Met) genotype, which was significantly more frequent in the cases than controls (47% vs. 19%), confers 3– 4 times lower COMT enzyme activity. Our preliminary findings implicate the dopaminergic pathway in the etiology of suicidal behavior in affective mood disorders. P110 ASSOCIATION OF CYTOSOLIC PHOSPHOLIPASE A2 GENE POLYMORPHISM WITH SCHIZOPHRENIA Czerski P,2 Dmitrzak-We¸glarz M,2 Kapelski P,1 Godlewski S,2 and Hauser J1,2 1 Department of Adult Psychiatry, University of Medical Sciences, Poznan, Poland 2 Laboratory of Psychiatric Genetics, University of Medical Sciences, Poznan, Poland

Direct and indirect evidence of disturbed levels of PLA2 activity in schizophrenics was reported. It is a base for a phospholipid hypothesis of schizophrenia. The human cytosolic PLA2 (cPLA2) gene is located on chromosome 1q25. A single nucleotide polymorphism (SNP) in the first intron of the gene (BanI polymorphic site) was the subject of the study. Population analysed consisted of 238 patients with schizophrenia (145 male and 93 female) of mean age 30 years (SD ¼ 10) diagnosed according to DSM-IV criteria (confirmed with SCID questionnaire) and 343 healthy volunteers (133 male and 210 female) with mean age 42 years (SD ¼ 10) of Polish origin. We found a statistically significant difference in genotype distribution between patient and control group (P ¼ 0.011). When subjects were divided according to gender the differences remained significant only for males (P ¼ 0.022), and not for females (P ¼ 0.251). There were neither significant differences in allele frequencies between patients and controls (P ¼ 0.491), nor when analysing males and females separately (P ¼ 0.531 for male and P ¼ 0.927 for female). Results obtained suggest that the cPLA2 gene may be involved in the risk of schizophrenia, however independent replication is required. The polymorphism we studied is probably not functional (intronic localisation). Possibly other functional polymorphism (s) in linkage disequilibrium with the studied variant are responsible for the observed association.

P111 NO ASSOCIATION BETWEEN COMT GENE MET/158 (108)/VAL POLYMORPHISM AND SCHIZOPHRENIA Czerski P,2 Godlewski S,2 Leszczyn´ska-Rodziewicz A,1 Kapelski P,1 Dmitrzak-We¸glarz M,2 and Hauser J1 1 Department of Adult Psychiatry, University of Medical Sciences, Poznan, Poland 2 Laboratory of Psychiatric Genetics, University of Medical Sciences, Poznan, Poland Catechol-O-methyltransferase (COMT) inactivates catecholamine neurotransmitters such as noradrenaline and dopamine. The COMT gene that maps to chromosome 22q11.1-q11.2 may be considered as a candidate gene in schizophrenia. A common Val108Met polymorphism of this gene determines different enzyme activity in human. The COMT gene polymorphism has been examined in schizophrenic patients, but with inconsistent results. In our study, we analysed the COMT polymorphism in 241 patients with schizophrenia (147 males and 94 females) and in 185 control subjects (105 males, 80 females). There were no statistically significant differences in the frequency of the alleles (P ¼ 0.368) and genotypes (P ¼ 0.505) between patients and controls. However, in the light of results from previous studies a minor effect of this polymorphism or an effect in a subset of schizophrenic patients cannot be excluded.

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P112 COMT GENE: LESSONS FROM PANIC DISORDER FOR ASSOCIATION STUDIES IN PSYCHIATRY Di Bella D,1 Deckert J,2 Martı´n-Santos R,3 Franke P,4 Grataco`s M,5 Fritze J,6 Garritsen H,2 Perna G,1 Pe´rez G,3 No¨then MM,4 Cucchi M,1 Armengol L,5 Bulbena A,3 Estivill X,5 Arolt V,2 Bellodi L,1 and Catalano M1 1 Fondaz Centro S Raffaele del Monte Tabor, DSNP, Milan, Italy 2 Univ. Depts. of Psychiatry and Transfusion Medicine, Mu¨nster, Germany 3 Dept. de Psiquiatria, Hospital del Mar, IMAS and IMIM, Barcelona, Spain 4 Univ. Depts. of Psychiatry and Human Genetics, Bonn, Germany 5 Genes and Disease Research Program, Barcelona, Spain 6 Dept. of Psychiatry, Frankfurt, Germany Panic Disorder (PD) is a common anxiety disorder, for which a genetic liability has been suggested. Catechol-O-methyltransferase (COMT) is a key modulator of catecholaminergic neurotransmission. A common functional polymorphism (Val158Met) in the coding sequence of COMT results in a three to fourfold reduction in enzyme activity. Evidence supports the hypothesis that COMT may play a role in anxiety disorders. We investigated 3 independent samples of PD patients, diagnosed according to DSM-IV criteria, for a possible association with COMT alleles using a case-control strategy. The samples were of Italian (PD ¼ 109, controls ¼ 109), German (PD ¼ 91, controls ¼ 91) and Spanish (PD ¼ 62, controls ¼ 72) descent. COMT distribution was significantly different between Italian and German controls. Moreover, in the Italian sample we found an excess of the low activity allele, while in the German and in the Spanish sample there was an excess of the high activity allele. A stratified analysis of the individual and the combined samples did not provide consistent results either, even after dividing the samples according to gender and clinical variables. COMT enzyme activity shows a wide variation among ethnic groups and this reflects different worldwide distribution of COMT alleles. Our results do not support the hypothesis that either of the COMT alleles plays a general etiopathogenetic role in panic disorder. Results from individual samples have to be taken with great caution when looking for an association between such a polymorphism and mental disorders.

P113 ASSOCIATION ANALYSIS OF FUNCTIONAL POLYMORPHISMS IN THE COMT AND DBH GENES AND MAJOR PSYCHIATRIC DISORDERS Dimitrova A,1 Georgieva L,1 Nikolov I,1 Owen MJ,2 Kirov G,2 and Toncheva D1 1 Department of Medical Genetics, Medical University, Sofia, Bulgaria

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Department of Psychologica Medicine, Neuropsychiatric Genetics Unit, University of Wales College of Medicine, Cardiff, UK The COMT and DBH genes encode enzymes involved in the metabolism of dopamine and noradrenaline which have been implicated in the aetiology of both schizophrenia (SZ) and bipolar affective disorer (BP). Functional polymorphisms have been identified in both COMT (Val108Met) and DBH (1021C-T). Homozygosity for the low-activity (Met) allele in COMT leads to a 3–4-fold reduction in enzymatic activity [Lachman et al., 1996: Pharmacogenetics 6:243–250]. The recently identified 1021C-T polymorphisms in the 50 flanking region of the DBH gene has been shown to account for 35– 52% of the variation in plasma DBH activity [Zabetian et al., 2001, Am J Hum Genet 68:515–522]. We examined these SNPs in a large sample of parent-offspring trios collected in Bulgaria. There were 182 SZ families genotyped for COMT. The frequency of the low-activity allele (Met) was 52.8% in the probands. It was transmitted 95 times and not transmitted 91 times from heterozygous parents, (T/NT ¼ 95/91; P ¼ 0.77). In the 72 BP families the frequency among the probands was only 45%, T/NT ¼ 30/42, but this difference did not reach statistical significance: P ¼ 0.16. For DBH we genotyped 267 SZ trios. The frequency of the low-activity (1021T) allele was 30% in probands, T/NT ¼ 110/96, P ¼ 0.33. In the 106 BP trios that we genotyped, the frequency of that allele was 27%, T/NT ¼ 40/44, P ¼ 0.66. We conclude that variation in the genes encoding COMT and DBH is unlikely to play a major role in the pathogenesis of major psychiatric disorders but we will investigate the possibility that it could influence certain features of the illness. P114 A HIGH ACTIVITY-RELATED ALLELE OF MAO-A GENE IS ASSOCIATED WITH DEPRESSIVE ILLNESS IN MALES Du L,1 Bakish D,1 Ravindran A,1 Faludi A,2 Palkovits M,2 Sotonyi P,2 and Hrdina P1 1 Institute of Mental Health Research at Royal Ottawa Hospital and University of Ottawa, Ontario, Canada 2 Semmelweis Medical University, Budapest, Hungary Abnormalities in brain monoamine oxidase A activity have been implicated in the pathogenesis of depressive illness and suicidal behavior. The present investigation was to determine whether a functional EcoRV polymorphism in the Xchromosomal MAO-A gene was associated with depression, suicide or both. Two independent case control association studies were carried out: First using postmortem brain samples from 44 depressed suicide victims and 92 controls, and the second using DNA samples from 191 depressed patients and 233 healthy control subjects. In the first study, we have found significant differences in genotype/allele distribution between depressed suicide victims and controls in males (P ¼ 0.012) but not in females or the total sample.

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The odds ratio (OR) for the high activity-related allele of the MAO-A gene associated with depressed suicide in males was 3.1. This finding was replicated in the second association study. The high activity-related allele of the MAO-A gene was associated with depression (OR ¼ 2.3, 95% CI 1.2-4.4) in male patients but no associations in the total sample and in female subjects were detected. Moreover, there was no significant difference in allele/genotype distribution of EcoRV polymorphism between patients with or without suicidal ideation even when the sample was stratified by sex. Our finding suggests that MAO-A may be a susceptibility gene in depressed males. (Supported by NATO and Royal Ottawa Hospital Foundation grants.)

P115 GENE-ENVIRONMENT INTERACTION ANALYSIS OF SEROTONIN SYSTEM MARKERS WITH ADOLESCENT DEPRESSION Eley TC, Sugden K, Gregory AM, Stern A, Plomin R and Craig IW Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, King’s College, London, UK We report preliminary analyses from the first wave of data collection from a study of gene-environment interaction in adolescent depression. The sample included 1990 adolescents aged 10 to 20 years. Adolescents with self-reported depression symptoms in the top or bottom 10% with either high or low (mean-split) levels of parent-reported environmental risk (a composite of education, negative life events and social problems such as poor housing) were contacted and asked to provide samples of DNA from buccal swabs. DNA was obtained from 336 unrelated adolescents representing the four quadrants of high or low depression and high or low environmental risk. One marker within or close to each of the serotonergic genes TPH, MAOB, HTR2C and HTR2A were genotyped. Environmental risk group and sex were both significant predictors of depression group, as was their interaction. Girls with high environmental risk were more likely to be in the high depression group than those with low environmental risk, whereas for boys the reverse was true. None of the genetic markers were associated with main effects of high versus low depression or main effects of high versus low environmental risk. In addition, no significant interaction was found between genotype and environmental risk as they relate to high versus low depression. Further data collection is underway in order to increase the sample size. P116 GLUTAMATE GLUR6 RECEPTOR GENE POLYMORPHISMS AND SCHIZOPHRENIA, BIPOLAR DISORDERS AND THEIR CLINICAL SUBTYPES Etain B,1,2 Schu¨rhoff F,1,2 Bellivier F,1,2 Szo¨ke A,1,2 Giros B,2 Rouillon F,1,2 Bourgeron T,3 and Leboyer M1,2

1

Service de psychiatrie adulte, Hoˆpital Albert Chenevier et Henri Mondor (Assistance Publique-Hoˆpitaux de Paris), France 2 Laboratoire INSERM U513 ‘Neurobiologie et psychiatrie’, Hoˆpital Henri Mondor, Cre´teil, France 3 Laboratoire d’immunoge´ne´tique humaine, INSERM E021, Institut Pasteur, Paris, France

There is accumulating evidence to suggest that alterations in glutamatergic neurotransmission may play a role in the pathophysiology of schizophrenia. We investigated three biallelic polymorphisms located in the 30 region of GRIK2 gene that encodes for the GluR6 kainate receptor subunit in schizophrenic patients (n ¼ 100), bipolar patients (n ¼ 100) and controls (n ¼ 100). The C/T single nuleotide polymorphism (SNP) in intron 14 is located 8 bp from exon 15. The G/A SNP is located in exon 15. The G/A SNP in exon 16 was genotyped with EcoRV which digests when A (Isoleucine) but not G (Methionine) is present1 All subjects were Caucasian (at least three grand parents from mainland France). Control subjects are free of personal and familial history of psychotic, mood and suicidal disorders. We found a significant difference for Met/Iso allele between control subjects and schizophrenic patients (w2 ¼ 4.31, df ¼ 1, P ¼ 0.037 for genotype distribution) and for the G/A allele between early onset schizophrenic patients (age at onset before 18) and control subjects (w2 ¼ 10.22, df ¼ 2, P ¼ 0.006 for genotype distribution). We also found a difference for the C/T allele between schizophrenic patients with comorbid substance abuse and control subjects (w2 ¼ 5.70, df ¼ 2, P ¼ 0.057 for genotype distribution). No association was found between these polymorphisms and bipolar patients. None of these associations obtained in schizophrenic subgroups remain significant after correction for multiple testing. This is the first report of an association between the GRIK2 gene polymorphisms and schizophrenia. It needs to be replicated in independent samples. P117 FAMILY-BASED ASSOCIATION STUDIES OF COMT GENE POLYMORPHISMS AND SCHIZOPHRENIA IN CHINESE POPULATION Fan J,1,5 Chen W,1,5 Tang J,1,5 Li S,1,2 Gu N,3 Feng S,3 Breen G,4 St Clair S,4 and He L1,5 1 Shanghai Research Center of Life Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, China 2 Mental Health Research Institute, University of Michigan, Ann Arbor, Michigan 3 Shanghai Institute of Mental Health, China 4 Dept of Mental Health, University of Aberdeen, UK 5 Bio-X Life Science Research Center, Shanghai Jiao Tong University, China Catechol-O-methyltransferase (COMT) is a major component of the metabolic pathways of neurotransmitters such as

Abstracts

dopamine, adrenaline, and noradrenaline. It has long been considered as a candidate for the vulnerability to schizophrenia in view of both its function and location in the genome. Recently, significant association between COMT and schizophrenia has been reported from two groups using family-based association studies on two different populations, and a possible mechanism of how COMT variation increases risk for schizophrenia has been suggested. To further investigate the role of the COMT in schizophrenia susceptibility, we tested the transmission of five SNP markers in COMT gene region from parents to schizophrenic offspring in 166 Chinese family trios. The extent of linkage disequilibrium between the polymorphisms was investigated, and individual markers and haplotypes were analysed for transmission distortion in the family trios using the transmission disequilibrium test (TDT). No preferential transmission of any allele or haplotype was detected for any of the polymorphisms. These data suggest that COMT gene is unlikely to play a major role in the aetiology of schizophrenia in Chinese population.

P118 INVESTIGATION OF THE SCA8 LOCUS ON 13q21 IN MAJOR PSYCHOSES Fortune MT, Kennedy JL, and Vincent JB Clarke Division Centre for Addiction and Mental Health, Toronto, Canada Expanded triplet repeats, located in the 30 exon of a noncoding gene, SCA8, which have been shown to segregate with spinocerebellar ataxia (SCA) in a large kindred, have also been found in twice as many unrelated major psychosis cases (1.25%) as unaffected controls (0.7%). The expansions (100–1300 repeats) occur at a frequency higher than that expected for SCA8, a disorder which has a frequency of 1 in >125000. We have confirmed this high frequency of expansion by genotyping a new cohort of unrelated schizophrenia and bipolar disorder patients and identified expansion mutation at the SCA8 locus in 5 out of the 260 patients examined (1.9%). The most 50 exon of SCA8 overlaps the first exon of a coding gene, Kelch-like 1, KLHL1, which is transcribed in the opposite orientation to the non-coding SCA8. We have screened all 11 exons of KLHL1 for mutations in a screening set of 73 psychosis probands, including 16 with large SCA8 repeats. Using DHPLC, DNA variants have been identified at exons 1, 2, 3, 7 and 10. However, only silent or intronic variants were found. Preliminary analysis of methylation by restriction enzyme digest and Southern blot has been carried out. Evidence of CpG hypomethylation at this site indicated by complete BssHII digestion was found in 39 control lymphocyte DNAs and 16 test lymphocyte DNAs from individuals with large repeats at SCA8. However, the same experiment performed using lymphoblastoid cell line

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DNAs from CEPH pedigrees #1334 and #1416, which both include members with large SCA8 repeat alleles, exhibit polymorphic hypermethylation at the BssHII site. Hypermethylation at the BssHII site appears to be specific only to lymphoblastoid DNA, and only from some of the family members with SCA8 expansion. Affected status for the CEPH families is currently unknown, however we speculate that DNA modification, i.e. polymorphic hypermethylation as a result of triplet repeat expansion, (TRE), may also occur in tissues expressing SCA8 and/or KLHL1, and may modulate the pathogenicity of the TRE.

P119 ANALYSIS OF FUNCTIONAL PROMOTER POLYMORPHISMS ON CHROMOSOME 21 IN MAJOR PSYCHIATRIC DISORDERS Georgieva L,1 Buckland P,2 Hoogendoorn B,2 Dimitrova A,1 Toncheva D,1 Kirov G,2 Owen MJ,2 and O’Donovan M2 1 Department of Medical Genetics, Medical University Sofia, Bulgaria 2 Neuropsychiatric Genetics Unit, UWCM, Cardiff, UK Regulatory elements within the promoters of genes could be important in the etiology of complex diseases. The laboratory in Cardiff is engaged in a large functional genomics study aiming at identifying polymorphisms in the promoters of genes and assessing their functional significance through reporter gene analysis. Provisional data on the first 60 promoters suggested that around 20–25% of polymorphisms in promoters alter expression by at least 50%. In this study we included 36 SNPs in 28 genes that lie within an area on chromosome 21q which is strongly implicated in psychiatric genetics through linkage studies. Our aim was to find out whether the promoter SNPs have a role in the pathogenesis of schizophrenia (SZ) and bipolar affective disorder (BP). We examined the frequency of these alleles in patients and controls, as well as in affected probands and their parents. In order to reduce the cost and the time-scale of the project, we first genotyped these polymorphisms on four sets of DNA pools made up of the parents and affected offspring and unrelated cases and controls. We used pools of 126 SZ trios and 121 BP trios of Bulgarian origin, a pool of 176 cases and 182 UK controls and a pool of 110 UK BP trios. SNPs genotyping was performed with primer extension using fluorescently labelled primers on ABI 373 sequencers. 20 of the SNPs were not polymorphic in these populations. From the remaining 16 SNPs, five satisfied our criteria for performing individual genotyping. These were within the promoters of the following genes: CRYZL1 gene in BG SZ pool: P ¼ 0.05, PKNOX1 gene in case-controls UK pool: P ¼ 0.09, SH3BGR gene in UK BP trio pool: P ¼ 0.11, CRYAA gene in BP BG trios pool: P ¼ 0.12 and HLCS gene in both SZ BG pool and UK BP trio pools: P ¼ 0.15. We are now individually genotyping these SNPs in order to confirm the obtained results.

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P120 GENETIC AND PHYSICAL MAPPING IN THE AUTISTIC DISORDER REGION ON CHROMOSOME 15q11-q13 Kim SJ, Menold MM, Shao Y, Cuccaro MA, Pericak-Vance MA, and Gilbert JR Department of Medicine and Center for Human Genetics, Duke University Medical Center, Durham, North Carolina Chromosome 15q11-q13 has been implicated in the genetic etiology of autistic disorder (AutD). Genes for three GABA receptor subunits, GABRb3, GABRa5 and GABRg3 are located on chromosome 15q11-q13. Using Ordered Subsets Analysis (OSA) [Shao et al., this meeting] we identified a clinically homogeneous subset of chromosome 15 linked families [Cuccaro et al., this meeting]. The autisticassociated quantitative trait we selected and named ‘‘resistance to change’’ uses ADI-R items 73, 74 and 75.25% of the total multiplex data set gave a maximum nonparametric LOD score of 3.2, and peak parametric two-point linkage a LOD score (dominant model) of 4.7 at the GABRb3 subunit. Using the pedigree disequilibrium test and single nucleotide polymorphisms within and adjacent to this gene we also found evidence for linkage disequilibrium (P ¼ 0.03) with a marker GABRb3 approximately 60 kb beyond the 30 -end of the b3 subunit. These data support GABRb3 or a gene within this immediate region as the chromosome 15 Aut (D) candidate gene targeting this area for further analysis. Subsequently, we have identified and sequenced 45 unique CpG islands, several of which map 30 to GABRb3, that meet full CpG island criteria in the candidate region. To further fine map and look for association in the candidate GABRb3 region we are genotyping known SNPs and SNPs developed in house from these CpG island clones and adjacent sequence that span the GABRb3 gene and the region 30 in the OSA families in order to fine map the chromosome 15 gene. SNP mapping and association results will be presented. P121 ASSOCIATION ANALYSIS BETWEEN A FUNCTIONAL POLYMORPHISM IN THE MONOAMINE OXIDASE A GENE PROMOTER AND SEVERE MOOD DISORDERS Gutie´rrez B,1 Arias B,1 Gasto´ Cristo´bal,2 Catala´n R,2 Papiol S,1 Pintor L,2 and Fan˜ana´s L1 1 Unitat d’Antropologia, Facultat de Biologia, Universitat de Barcelona, Spain 2 Centre de Salut Mental Esquerra de l’Eixample, Hospital Clı´nic i Provincial de Barcelona, Spain Monoamine oxidase A (MAOA) has been suggested to be involved in human behaviour and physiology due to its key role in the metabolism of several different biological amines including the neurotransmitters serotonin, norepinephrine and dopamine. Recently, a 30 bp repeat in the MAOA gene promoter has been demonstrated to be polymorphic and to affect transcriptional activity. Although negative results have

been described, several different studies have shown an association between high-activity alleles (long alleles) of the MAOA promoter polymorphism with both panic attacks and mood disorders, especially in females. In the present study, we explored the possible implication of MAOA gene in the aetiology of severe mood disorders. In the context of an association case-control study design, genotypes of the 3 to 5 repeat variants were assessed in 389 unrelated patients of Spanish descent (88 DSM-III-R bipolar subjects and 301 DSM-IV major depressive individuals) and 156 controls. None of the different repeat copies was found to be associated with major mood disorders. No global differences were found according to family history of major mental disorders, seasonal pattern, psychotic symptoms, suicide, comorbidity, recurrence, age of onset or Hamilton scores at index episode. However, we found a non-significant (after Bonferroni correction) trend for the total group of female patients with early age of onset, psychotic symptoms and seasonal pattern to have a higher frequency of high-activity MAOA alleles when compared with females with late age of onset (w2 ¼ 4.370, df ¼ 1, P ¼ 0.036), no psychotic symptoms (w2 ¼ 2.679, df ¼ 1, P ¼ 0.070) and no seasonal pattern in their episodes (w2 ¼ 3.013, df ¼ 1, P ¼ 0.055) respectively. These trends were also observed when bipolar patients and depressive subjects were analysed separately. Our results suggest that MAOA gene variation may modulate the expression of some clinical aspects of mood disorders and support the existence of a genetic and etiologic heterogeneity underlying the diagnoses of bipolar disorder and major depression. P122 WEAK EVIDENCE OF ASSOCIATION BETWEEN MAOA FNU4H1 POLYMORPHISM AND ADHD IN IRISH POPULATION Hawi Z, O’Sullivan R, Lowe N, Kirley A, Fitzgerald M, and Gill M Department of Genetics and Psychiatry, Trinity College, Dublin, Ireland ADHD is the most common neuropsychiatric condition affecting school age children worldwide. Like many other related disorders, ADHD is thought to be polygenic and several genes each of minor effect are involved in predisposing to it. Imbalance in the dopaminergic neurotransmission has been postulated to play an important role in predisposing to ADHD. Monoamine oxidase A plays a central role in the controlled degradation of the biogenic amines and catecholamines which are central components of the dopaminergic neurotransmission system. Polymorphic regions of the MAOA gene have been linked with abnormal levels of the enzyme in mouse models and have been implicated in the onset of the Brunner Syndrome—a condition that displays a high comorbidity with ADHD. One such polymorphism is a G-T substitution at position 941 (Fnu4H1 polymorphism) of the MAOA gene. This has made the

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MAOA gene a candidate for ADHD. In this investigation, we carried out a TDT analysis on 109 Irish nuclear ADHD families to assess the possible involvement of this polymorphism in ADHD. We observed an increased transmission (TDT) of allele 2 (T) of the MAOA gene to ADHD cases but it was not statistically significant (w2 ¼ 3.0, P ¼ 0.11). The insignificant increase in the transmission of this allele may reflect a linkage disequilibrium with another marker located in or close by the MAOA gene. Analysis of more markers is required to determine the importance of this locus in the development of ADHD.

P123 INVESTIGATING THE ROLE OF SELECTED CANDIDATE GENES IN OBSESSIVE-COMPULSIVE DISORDER: A CASE-CONTROL ASSOCIATION STUDY IN THE AFRIKANER POPULATION Hemmings SMJ,1,2 Kinnear CJ,1,2 Moolman-Smook JC,1 Lochner C,2 Corfield VA,1 and Stein DJ2 1 MRC Centre for Molecular and Cellular Biology, University of Stellenbosch, South Africa 2 MRC Unit on Anxiety and Stress Disorders, University of Stellenbosch, South Africa There is increasing evidence that obsessive-compulsive disorder (OCD) has a marked genetic component, although the precise mechanism of inheritance is unclear. Numerous association studies have been attempted, but these have generally yielded disparate results. Current models of candidature are based on gene products being targets for successful pharmacotherapy, their roles in neurotransmission and expression profiles in regions of the brain implicated in pathogenesis of OCD. Therefore, to date, research has focussed on genes encoding components in the serotonergic (5HT) and dopaminergic (DA) systems. However, signal transduction pathways are capable of affecting functional balance between multiple neurotransmitter systems and may play a role in mediating downstream alterations in neurotransmitter and physiological processes. Thus, the clinical picture of OCD is likely to be a result of a complex, dynamic interaction between dysregulated signalling and neurotransmitter systems. The present study therefore assessed the role of genetic variants in attractive candidates within the 5HT, DA, and phospholipase-C signal transduction systems in OCD pathogenesis, using the genetically homogeneous Afrikaner population in case-control association studies. A comparison of genotypic and allelic distribution of the polymorphisms in 110 OCD and 220 control individuals yielded no statistically significant results, after correction for multiple testing. However, finer analyses of the data yielded interesting preliminary results which warrant further investigation. The results also emphasize the value of auxiliary studies in the genetically homogeneous Afrikaner population to help delineate the complex aetiology of the disorder.

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P124 MSX1 AND HIGH COGNITIVE ABILITY Hill L,1 Butcher LM,1 Chase D,2 Rowe D,2 and Plomin R1 1 SGDP Research Centre, Institute of Psychiatry, King’s College London, UK 2 Division of Family Studies and Graduate Program in Genetics, University of Arizona, Tucson, Arizona The IQ QTL project is an ongoing study looking for genes of small effect (Quantitative Trait Loci, QTLs) associated with cognitive ability. In order to detect QTLs of small effect size, we use extreme selected samples and a multi-stage design to test any putative loci. Our original sample consists of 101 cases with mean IQ of 136 and 101 controls with mean IQ of 100. Positive associations are then tested in our replication sample (96 cases with IQ > 160 and 100 controls with mean IQ of 100). As a final hurdle, markers are then submitted to a within-family sample (196 parent-child trios for offspring with IQ > 160). Use of these extreme selected samples increases power and the multiple replication stages guards against false positives. MSX1 is a member of the homeobox family of genes that play essential roles during embryonic development, and has been shown to contribute to multiple stages of central nervous system differentiation. The MSX1 gene is located on chromosome 4p16 and has 2 exons. A simple sequence repeat (SSR) marker in the MSX 1 gene was originally studied in an earlier phase of the IQ QTL project, which studied 1842 SSR markers at 2 cM intervals throughout the autosomes. A significant association was found between the MSX1 SSR marker and high g, using DNA pools. However, the marker was not significant in a replication sample. Subsequently, a different MSX1 polymorphism, an intron 1 insertion/deletion, beginning 8bp after the 30 end of exon 1 was genotyped in our original sample of 101 cases with mean IQ of 136 and 101 controls with mean IQ of 100. A significant association between the insertion and high IQ was observed (P ¼ 0.003). We genotyped our replication sample and the association was confirmed (P ¼ 0.03). We are currently examining this marker in our within-family sample in an attempt to further replicate this finding.

P125 NO EVIDENCE FOR LINKAGE BETWEEN THE SEROTONIN TRANSPORTER AND 2A RECEPTOR GENE IN ADULT ADHD Inkster B,1,2 Muglia P,1,2 Jain U,2 and Kennedy JL1 1 Neurogenetics Section 2Adult ADHD Clinic, Centre for Addiction and Mental Health, Clarke Site, Department of Psychiatry, University of Toronto, Canada A substantial body of literature has accumulated over time demonstrating the modulatory effect of serotonin on dopaminergic transmission. In both human and animal subjects, studies have indicated that the serotonergic system is critical for modulating such behavioral phenotypes as impulse

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control, hyperactivity and inhibition. As such, these phenotypes can be extremely useful for investigating conditions associated with attention deficit hyperactivity disorder (ADHD). Previously, our group [Quist et al., 2000] has shown a modest positive association between the 5HT2A receptor gene and childhood ADHD. In view of these findings, molecular genetic studies on ADHD need to incorporate candidate genes of the serotonergic system. In our study, we tested for linkage disequilibrium between adult ADHD and markers in the 5HT2A and 5HTT genes. We used the following two polymorphic regions: the MspI polymorphism (T102C) of the 5HT2A receptor gene (HTR2A) in 68 triads, and the 44-bp deletion polymorphism in the promotor region of the serotonin transporter (5-HTTLPR) in 62 triads. Results from the TDT analysis provided no indication for the preferential transmission of either allele of the MspI polymorphism, although a weak trend was observed for the C allele (36 times transmitted vs. 27 times non-transmitted; w2 ¼ 1.29, 1df, P ¼ 0.26). The 5-HTTLPR polymorphism revealed no evidence to suggest that a biased transmission of either allele had occurred (short allele: 27 times transmitted vs. 32 times non-transmitted; w2 ¼ 0.42, 1df, P ¼ 0.52). Although preliminary, the results from our sample exclude a strong association between the T102C site of the 5HT2A receptor gene or the 44-bp deletion polymorphism of the 5HTT gene in adult ADHD.

P126 MUTATION SCREENING OF THE HUMAN 5-HT4 RECEPTOR GENE IN JAPANESE SCHIZOPHRENIA Iwata N,1 Suzuki T,1 Kitajima T,1 Yamanouchi Y,1 Ikeda M,1,2 Nishiyama T,1,3 Abe T,1 and Ozaki N1 1 Department of Psychiatry, Fujita Health University School of Medicine, Toyoake, Aichi, Japan 2 Department of Psychiatry, Nagoya University School of Medicine, Japan 3 Department of Psychiatry, Nagoya City University School of Medicine, Japan Several different types of evidence suggest that genes involved in serotonergic neurotransmission are possible factors in the pathogenesis of schizophrenia. The human serotonin 5-HT receptor subtype 4 gene (HTR4) is a phathophysiological and positional candidate gene in schizophrenia. Using the case-control analysis, the current study assesses for linkage disequilibrium between polymorphisms in HTR4 and Japanese schizophrenia. The region of HTR4 was screened in unrelated 96 schizophrenic patients by a denaturing high-performance liquid chromatography (DHPLC) analysis. We detected one synonymous single nucleotide polymorphism (SNP) in the coding region and six SNPs in the

introns.189 patients and 299 healthy volunteers were genotyped by a PCR-RFLP or a primer extension using DHPLC. Haplotype analysis revealed that haplotype AT was significantly decreased in schizophrenia (OR ¼ 0.16: 95% CI [0.07–0.37]). Our findings suggest that the gene for 5-HT4 receptor, or a locus in linkage disequilibrium with it, confer susceptibility to schizophrenia.

P127 WKL1 GENE: DOES IT PLAY ANY ROLE IN ISRAELI JEWISH PATIENTS WITH MAJOR PSYCHOSIS? *Kaganovich M,1,3 Peretz A,2,3 Bening Abu-Shach U,1 Ben-Zeev B,3 Ritzner M,4 Attali B,2 and Navon R1 1 Department of Human Genetics, Sackler School of Medicine, Tel Aviv 2 Department of Physiology, Sackler School of Medicine, Tel Aviv University, Israel 3 Pediatric Neurology, Tel-Hashomer Hospital, Ramat Gan 4 Shaar Menashe, Mental Health Center, Hadera, Israel A Leu309Met mutation in WKL1 (MLC1, KIAA0027) gene, mapped to 22q13 a region highly associated to schizophrenia, was reported to co-segregate with periodic catatonic schizophrenia in a large German pedigree. We screened 143 Israeli Jewish patients with major psychosis (64 Ashkenazim and 79 non-Ashkenazim) and 167 matched controls. No such mutation was revealed in patients or controls. Our findings do not support the possibility that the Leu309Met mutation contributes to the susceptibility of major psychosis in Israeli Jews. In order to test the putative channel activity of WKL1, the human KIAA0027 cDNA was subcloned into pcDNA3. No significant current in the transfected CHO cells was recorded following hyperpolarizing or depolarizing pulses. The absence of significant current suggests that under these experimental recording conditions WKL1 does not exhibit a putative channel activity. It is possible that WKL1 by itself is a silent channel subunit or that it requires an additional channel subunit in order to form a functional channel. Recenty, 26 different mutations in the MLC1 (WKL1) gene were reported to cause Megalencephalic Leukoencephalopathy with Subcortical Cysts (MLC), an autosomal recessive disorder. It seems very unlikely that mutations in the MLC1 (WKL1) gene will also be associated to any subgroup of major psychosis. It seems however that the D22S1169 marker linked to the catatonic German patients is probable in linkage disequilibrium with the proximal markers UT580 and 355c18 or with 355c18 and ARSA, the region of the MLC1 gene. Additionally, the fact that no psychosis was seen in 5 non-Ashkenazi Jews families with MLC (patients or normals) also argues against the involvement of the WKL1 (MLC1) gene with susceptibility to major psychosis.

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P128 ASSOCIATION ANALYSIS OF SEROTONIN 2A RECEPTOR GENE T102C POLYMORPHISM AND SCHIZOPHRENIA Kapelski P,1 Czerski P,2 Leszczyn´ska-Rodziewicz A,1 Dmitrzak-Weˆglarz M,2 Godlewski S,2 and Hauser J1,2 1 Department of Adult Psychiatry, University of Medical Sciences, Poznan, Poland 2 Laboratory of Psychiatric Genetics, Department of Psychiatry, University of Medical Sciences, Poznan, Poland Serotonin is one of the neurotransmitters, which has been implicated in the pathogenesis of mood disorders and schizophrenia. Serotonin receptor genes may be candidates for the study of the genetics of these disorders. In this study, patients with schizophrenia (n ¼ 242), diagnosed with SCID and controls (n ¼ 341) were analysed to determine the relation between the 5HT2A receptor gene T102C polymorphism and schizophrenia. No association was found between the studied polymorphism and schizophrenia (P ¼ 0.670 for alleles and P ¼ 0.884 for genotypes). The frequency of alleles in schizophrenia patients and controls were respectively: T- 60.1% vs. 61.4%; C- 39.9% vs. 38.6% and genotypes: T/T- 35.5% vs. 37.5%; T/C- 49.2% vs. 47.8%; C/C- 15.3% vs. 14.7%. Results remained not significant also when a division according to gender was performed; for male P ¼ 0.604 (allele frequency) and P ¼ 0.447 (genotype frequency), for female P ¼ 0.857 (allele frequency) and P ¼ 0.844 (genotype frequency). Allele frequencies in male subjects of schizophrenia and control group were respectively: T- 60.5% vs. 62.9%; C- 39.5% vs. 37.1% and genotype: T/T- 35.8% vs. 41.9%; T/C- 49.3% vs. 41.9%; C/C- 14.9% vs. 16.2%. In female: T- 59.6% vs. 60.5%; C- 40.4% vs. 39.5%; T/T- 35.1% vs. 34.6%; T/C- 48.9% vs. 51.7%; C/C- 16.0% vs. 13.7%. In conclusion, we did not find an association between the T102C polymorphism of the 5HT2A receptor gene and schizophrenia. P129 LACK OF ASSOCIATION BETWEEN-141C INS/DEL POLYMORPHISM OF DRD2 GENE AND SCHIZOPHRENIA Kapelski P,1 Czerski P,2 Godlewski S,2 Dmitrzak-We˛glarz M,2 and Hauser J1,2 1 Department of Adult Psychiatry, University of Medical Sciences, Poznan, Poland 2 Laboratory of Psychiatric Genetics, Department of Psychiatry, University of Medical Sciences, Poznan, Poland The association study was conducted to investigate frequencies of alleles and genotypes of the DRD2 gene in a group of patients with schizophrenia and in healthy controls. Specifically, we examined a DRD2 gene promoter polymorphism which is characterizedby an insertion or deletion of the cytosine in position -141 of the 50 -flanking region of this gene. No relationship between this polymorphism and schizophrenia was detected (P ¼ 1 for alleles and P ¼ 0.239 for genotypes).

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Frequencies of alleles were identical in schizophrenia patients and controls: Ins 0.89, Del 0.11; genotype distribution was as follows: Ins/Ins 77.2% vs. 78.6%, Ins/Del 22.8% vs. 20.2%, Del/Del 1.2% vs. 0%. Results remained not significant after dividing the sample according to gender: for male P ¼ 0.322 (allele frequency) and P ¼ 0.286 (genotype frequency), for female P ¼ 0.186 (allele frequency) and P ¼ 0.234 (genotype frequency). Allele frequencies in male schizophrenia patients and controls were: Ins 86% vs. 90%, Del 14% vs. 10%; genotype frequencies: Ins/Ins 72.6% vs. 79.2%, Ins/Del 27.4% vs. 20.8%, and no men with Del/Del genotype. In females: Ins 92% vs. 88%, Del 8% vs. 12%, Ins/ Ins 84.5% vs. 77.8%, Ins/Del 15.5% vs. 19.4%, Del/Del 0% vs. 2.8%. In conclusion, we did not find an association between the promoter polymorphism of the DRD2 receptor gene and schizophrenia. P130 ASSOCIATION ANALYSIS OF THE HOPA (12BP) POLYMORPHISM IN SCHIZOPHRENIA AND MANIC DEPRESSIVE ILLNESS Kirov G,1 Georgieva L,2 Nikolov I,2 Zammit S,1 Jones G,1 Poriazova N,3 Tolev T,4 Owen R,1 Jones S,1 Toncheva D,2 and Owen MJ1 1 Neuropsychiatric Genetics Unit, Department of Psychological Medicine, Tenovus Building, University of Wales College of Medicine, Cardiff, UK 2 Department of Medical Genetics, Medical University, Sofia, Bulgaria 3 Psychiatric Dispensary, Higher Medical Institute, Plovdiv, Bulgaria 4 Psychiatric Hospital ‘Dr. Georgi Kissiov,’ Radnevo, Bulgaria Variations in exon 42 of the HOPA (human opposite paired) gene have been associated with mental retardation, hypothyroidism and psychiatric disorders. We attempted to replicate the association with schizophrenia using 309 parent-offspring trios from Bulgaria and 367 unrelated cases and 368 controls from the UK. We also tested 125 bipolar trios from Bulgaria, 112 bipolar trios from the UK and a sample of 178 unrelated bipolar cases and 188 controls from the UK. The frequency of HOPA (12 bp) allele in the 556 UK controls was 2.6% and it was not significantly different in the UK patients groups, where it ranged from 1.2% to 3.8%. Sixteen mothers transmitted the HOPA (12 bp) allele to schizophrenic offspring, while 12 did not transmit, a non-significant difference. There was a trend for under-transmission of the rare allele to bipolar patients (T/NT ¼ 4/10) and they had a lower rate of that allele than schizophrenic patients in the Bulgarian population (1% vs. 4.2%, P ¼ 0.043). However the two diagnostic groups had similar allele frequencies in the UK populations: 2% vs. 2.6%, P ¼ 0.6. In 61 patients or parents there was a history of thyroid disorder. The frequency of the rare allele was not increased in these individuals. We conclude that the HOPA polymorphism is unlikely to play a role in

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the pathogenesis of these major psychiatric disorders or in thyroid disorders associated with psychiatric illness, such as lithium-induced hypothyroidism.

P131 FAMILY-BASED ASSOCIATION /ANALYSIS OF SYNAPSIN III GENE POLYMORPHISMS IN SCHIZOPHRENIA Klempan TA,1 Trakalo J,1 Pato C,2 Azevedo MH,2 Macciardi F,1 and Kennedy JL1 1 Neurogenetics Section, Clarke Division, Centre for Addiction and Mental Health, Toronto, Canada 2 Department of Psychiatry, The University of Coimbra, Portugal The synapsins constitute the most abundant synaptic vesicle membrane proteins, with suggested roles in vesicle mobilization, axon formation, and neural plasticity. The phosphorylation-dependent association of synapsins with actin microfilaments serves to regulate the recruitment of vesicles, in turn controlling the kinetics of neurotransmission and synaptic strength. The synapsins show significant expression in the brain and several reports have revealed reduced expression of synapsins in the brains of schizophrenic individuals. The recently identified synapsin III gene has been localized to chromosome 22q13, within 5 cM of D22S278, a dinucleotide repeat marker previously associated with schizophrenia. We have investigated the possible role of synapsin III in the pathogenesis of schizophrenia through analysis of two substitution polymorphisms within the promoter region (-631C/G and 196G/A) and a dinucleotide repeat (D22S280) located within intron 5 of the gene. These polymorphisms were studied in a combined sample of 228 small nuclear schizophrenia families, 123 families of variable ethnicity and 105 families from mainland Portugal and the Azores islands. Transmission of alleles to affected individuals was examined using TDT-sTDTand the family-based association test (FBAT). No significant differences in inheritance of these alleles was observed using TDT (-631C/G w2 ¼ 1.143, P ¼ 0.285; -196G/A w2 ¼ 0.681, P ¼ 0.409; D22S280 allele 6 w2 ¼ 2.139, P ¼ 0.952 (7df)). Similarly, differences were non-significant on inclusion of additional pedigree information using FBAT (multi-allelic, dominant model: -631C/G w2 ¼ 0.518, P ¼ 0.772 (2df); -196G/A w2 ¼ 0.246, P ¼ 0.884 (2df); D22S280 w2 ¼ 4.591, P ¼ 0.710 (7df)). These findings suggest that synapsin III is unlikely to act as a major susceptibility factor for schizophrenia.

P132 NO ASSOCIATION BETWEEN THE NOREPINEPHRINE TRANSPORTER GENE POLYMORPHISM AND BIPOLAR DISORDER Leszczyn´ska-Rodziewicz A,1 Samochowiec J,3 DmitrzakWe˛glarz M,2 Czerski P,2 Hauser J,1 and Rybakowski J1

1

University of Medical Sciences, Department of Adult Psychiatry, Poznan, Poland 2 Laboratory of Psychiatric Genetics, University of Medical Sciences, Poznan, Poland 3 Pomeranian University of Medical Sciences, Department of Psychiatry, Szczecin, Poland An association between the norepinephrine level and mood disorders is well known, since the publication of Schildkraut. In the present study the 1287A/G polymorphism in the norepinephrine transporter (NET) gene was studied in a group of 100 patients with bipolar disorder type I, diagnosed with SCID, and 211 healthy controls. We did not observe an association at the allelic level (P ¼ 0.928), nor at the level of genotypes (P ¼ 0.947). Separate analysis of both genders showed also no significant differences in allele (P ¼ 0.707 for males, P ¼ 0.598 for females) and genotype frequencies (P ¼ 0.657 for males, P ¼ 0.775 for females). In conclusion, our results do not support a causal contribution of genetic variation within the NET gene to the development of bipolar disorder.

P133 5-HT2A, COMT AND MAO-A GENE VARIANTS AND SYMPTOMATOLOGY OF MAJOR PSYCHOSES Lorenzi C, Serretti A, Lattuada E, Lilli R, and Smeraldi E Department of Psychiatry, Vita-Salute University, San Raffaele Institute, Milano, Italy In recent years, several research lines suggested that the use of traditional psychiatric diagnoses as phenotype definition does not guarantee biological homogeneity. We developed a complementary definition of psychiatric phenotype based on four symptomatological factors derived from the Operational Criteria for Psychotic Illness (OPCRIT): Excitement, Depression, Delusion, Disorganisation and Negative. Family studies evidenced a slight but significant heritability for all factors. We analysed in a sample of inpatients affected by major psychoses, gene variants in MAO-A (Monoamine Oxydase A, n ¼ 1393), COMT (catechol o-methyltransferase, n ¼ 872) and 5-HT2A (serotonin receptor 2A: 102T/C variant, n ¼ 942 and -1420C/T polymorphism, n ¼ 936). We observed an association between 5-HT2A 102T/C CC genotype and disorganization symptomatolgy (P ¼ 0.016), particularly in bipolar subjects; moreover we observed an excess of 5-HT2A -1420C/T CC genotype in bipolars (P ¼ 0.0007), while MAO-A variants showed no association with either diagnoses or factors. Further, a marginal association of COMT*A containing variants and schizophrenia (P ¼ 0.026) and delusional symptomatology (P ¼ 0.07) was observed. Sex and early onset did not significantly influence results. Our analysis did not evidence strong liability factors for major psychoses, even when lifetime symptomatology was analysed.

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P134 HAPLOTYPE ANALYSIS OF THE DOPAMINE D5 RECEPTOR GENE: AN ATTEMPT TO NARROW THE REGION OF ASSOCIATION WITH ADHD Lowe N, Hawi Z, Kirley A, Mullins C, Fitzgerald M, and Gill M Departments of Genetics and Psychiatry, Trinity College, Dublin, Ireland. ADHD is a highly heritable disorder which affects 3–6% of all school aged children. Accepted hypotheses for its aetiology include abnormalities in dopaminergic transmission. We [Daly et al., 1999] reported significant increased transmission (w2 ¼ 16.36, P ¼ 0.00005) of a 148 bp allele of a (CA)n repeat located 18.5 kb from the 50 end of the dopamine D5 receptor gene. In the currant investigation, we genotyped additional markers, across and flanking the DRD5 gene to perform a haplotype analysis in an attempt to narrow the region of interest. Four additional markers were genotyped. Two microsatellites, D4S2928 and D4S1582 located approximately 166.7 kb and 64.5 kb from the 50 end of the gene, a silent Pro-Pro SNP at position 978 of the gene and a T-C variant mapped to the position 1481 at the 30 untranslated region of DRD5. HHRR analysis showed significant association between the D4S1582 (w2 ¼ 4.58, P ¼ 0.032) the 1481 (w2 ¼ 6.76, P ¼ 0.0093) and ADHD. Haplotype analysis using the program TRANSMIT showed significant association of a haplotype made up of the (CA)n repeat and the 978 variant (w2 ¼ 8.48, P ¼ 0.0036). Another haplotype made up of the 978 and 1481 variants was also associated with ADHD (w2 ¼ 6.86, P ¼ 0.0088). The haplotype constructed of the (CA)n repeat and 1481 at the DRD5 gene showed the most significant association with the disorder ADHD (w2 ¼ 14.21, P ¼ 0.00017). Linkage disequilibrium analysis between the examined markers showed strong positive D0 values between the (CA)n repeat and the 1481 (D0 ¼ 0.534) and the 978 and 1481 markers (D0 ¼ 0.511). This may indicate that the region between the marker (CA)n and the 1481 may contain a DNA variant that plays an important role in predisposing to ADHD. Structural analysis of the DRD5 in ADHD patients is required to locate this variant. P135 PRELIMINARY FINDINGS OF THE GEMINI -TARDIVE DYSKINESIA STUDY IN A POPULATION OF PATIENTS WITH SCHIZOPHRENIA & POOR OUTCOME SCHIZOAFFECTIVE DISORDER IN NORTHERN IRELAND Miller PW,1 McCusker JJ,1,2 McIlroy S,3 and O’Neill FA1,2 1 GEMINI Research, Department of Mental Health, The Queen’s University Belfast, N. Ireland 2 The Mater Hospital, Belfast 3 Department of Geriatric Medicine, The Queen’s University Belfast, N. Ireland

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This study describes the interim findings relating to the DRD3 and CYP1A2 candidate regions for Tardive Dyskinesia, in probands with schizophrenia, or poor outcome schizoaffective disorder. The DNA from both parents’ is available and the study will apply a TDT methodology. TD is a syndrome of abnormal involuntary movements, usually thought of as the most serious of the movement disorders resulting from neuroleptic drug-use. In the current literature, genetic variation in genes that encode products that are involved in oxidative stress (manganese superoxide dismutase geneMnSOD), the pharmacodynamics (DRD2, DRD3, HTR2A) and the pharmacokinetics (CYP2D6, CYP1A2) of typical antipsychotics may predict patient susceptibility to tardive dyskinesia [Tsai, Goff, Chang, et al., 1998]. Although several theories on the pathophysiology of TD exist, there has been no firm link made between these and the current candidate areas [Casey, 2000]. As such the risk that the various candidates are in linkage disequilibrium with a functional mutation is still a possibility. The data available in this study of probands with schizophrenia and poor outcome schizoaffective disorder includes Abnormal Involuntary Movement Scale, SCID, smoking history ‘current medication’ at assessment and age of onset. Data was entered and analysed using Pin Point & SPSS applications. Schooler & Kane Research Criteria for Tardive Dyskinesia were applied. In this preliminary analysis (n ¼ 103) we hope to replicate the findings of the recent meta-analysis [Lerer et al., in press] showing a significant contribution of the DRD3 ser9gly polymorphism to TD in our Irish sample. We also hope to demonstrate a significant contribution of the CYP1A2 C/C genotype to TD and that this risk conferred by the genotype is increased in those individuals who smoke.

P136 ADULT ADHD AND DRD4 7-REPEAT ALLELE: IS THE QUANTITATIVE STUDY OF PHENOTYPE AND PERSONALITY DIMENSIONS REVEALING ANYTHING NEW? Muglia P,1,2 Jain U,2 Inkster B,1 and Kennedy JL1 1 Neurogenetics Section, University of Toronto, Canada 2 Adult ADHD Clinic, CAMH, Department of Psychiatry, University of Toronto, Canada The 7 repeat allele (7R) of the dopamine D4 receptor gene (DRD4) has been reported, with numerous replications and in the overall metaanalysis, to be associated with ADHD in children and in our sample of adult patients. We investigated whether the 7R, that confers a relatively small increased risk for the disorder (odds ratio: 1.4 and 1.9 according to the results from the metaanalyses of case-control and family studies respectively), is more strongly associated with ADHD specific core symptoms or disorder severity. In 198 adult ADHD patients the Brown Attention Deficit Disorder Scale (BADDS) and the Wender Utah Rating Scale (WURS)

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were used to evaluate the quantitative phenotype. Furthermore, the assessment of personality dimensions via the Temperament and Character Inventory (TCI) was also available. Differences were observed between DRD4 genotypes and TCI mean scores, however none of these measures reached statistical significance. Quantitative TDT in the family did not reveal the presence of association between the 7R and BADDS or WURS scores. When we compared the mean scores of BADDS and WURS in the carriers of the 7R (7 þ) vs. patients without the 7R (7), higher mean scores were observed in the 7 þ patients. Gender specific analysis showed that the higher scores observed in the 7 þ patients were determined almost exclusively by the female patients (WURS mean 62.6 þ 18.2 vs 55.7 þ 18.2, t ¼ 1.5, P ¼ 0.1 in patients 7 þ vs 7 respectively; BADDS mean 88.9 þ 18.8 vs 84.6 þ 18.0, t ¼ 0.9, P ¼ 0.3). ADHD is more common in males than in females and all association studies of DRD4 in child ADHD were conducted in samples made up primarily of male patients. Our result, even though not reaching statistical significance for P ¼ 0.05, indicates that the 7R allele could be a stronger risk factor for females than males suggesting the need for a sex specific metaanalysis of the association studies.

P137 ASSOCIATION ANALYSIS OF SEROTONIN PATHWAY IN A SIBLING STUDY OF DEPRESSION AND ANXIETY (GENESiS) Nash MW, Huezo-Diaz P, Colledge E, Sugden K, Sterne A, Williamson R, Purcell S, Sham P, and Craig I Social, Genetic & Developmental Psychiatry Research Centre, London, UK The serotonin pathway contains potential candidate genes for depression, anxiety and neuroticism. Here, we present results of association analysis of five SSR markers located in five separate serotonin genes (5HTR1B, 5HTR1D, 5HTR2C, MAOB and TPH) in a sibling study of depression and anxiety (GENESiS; Sham et al., 2000). The GENESiS study collected information on anxiety (MASQ-AA), depression (MASQ-HPA), current psychological state (GHQ-12) and neuroticism (EPQ-N) from >30,000 individuals in the UK. These four scales were combined to give a composite index, which was used to select informative sibships for linkage analysis [Purcell et al., 2001]. The first wave of individuals (376 individuals; 147 families) was typed on the five SSR markers. Analysis using QTDT [Abecasis et al., 2000], suggest that no marker contributed significantly to the variation of the composite index. Significant results were obtained (alpha ¼ 0.05) for 5HTR1D and TPH on the individual scales contributing to the composite, but these did not survive adjustment for multiple testing. These negative results do not implicate the serotonin biochemical system as a cause of individual differences in depression and anxiety.

P138 NO LINKAGE DISEQUILIBRIUM BETWEEN (CA)n REPEAT IN INTRON 2 OF DOPAMINE D2 RECEPTOR GENE (DRD2) AND BIPOLAR DISORDER Ni X, Trakalo JM, Wong GWH, and Kennedy JL Neurogenetics Section, Centre for Addiction and Mental Health, Clarke Site, Department of Psychiatry, University of Toronto Based on the dopamine hypothesis, the dopamine D2 receptor gene (DRD2) is considered to be a good candidate gene for bipolar disorder (BP). Recently, Massat et al. [2002] reported a positive association of the (CA)n in intron 2 of DRD2 with BP based on a case control study. Our project is to test for the presence of linkage disequilibrium between (CA)n repeat of DRD2 and bipolar disorder. We genotyped the (CA)n polymorphism in intron 2 of DRD2 in 308 BP trios. The transmission disequilibrium test (TDT) was performed on the genotype data. With the extended transmission disequilibrium test (ETDT) we also calculated the maternal transmission and paternal transmission for each allele. Comparison of mean age at onset among probands with different (CA)n repeat genotypes was performed using analysis of variation (ANOVA). The (CA)n polymorphism of DRD2 was not associated with BP and its subtypes, bipolar I, bipolar II, and schizoaffective disorder, bipolar type (P > 0.05). Furthermore, no positive association for age of onset and DRD2 (CA)n repeat was observed (F ¼ 0.5412, P ¼ 0.8602). Our results indicate that the (CA)n polymorphism in the second intron of DRD2 may play no roles in the etiology of bipolar disorder. P139 CIS-4: A POSITIONAL CANDIDATE GENE FOR BIPOLAR AFFECTIVE DISORDER ON CHROMOSOME 18q22 Prathikanti S, Akula N, and McMahon FJ. Department of Psychiatry, University of Chicago, Chicago, Illinois Several studies have found evidence of genetic linkage between bipolar affective disorder (BPAD) and chromosome 18q [Stine et al., 1995; Freimer et al., 1996; McMahon et al., 1997; Noethen et al., 1999; Bennett et al., 2002]. Among the known genes within the linkage region is CIS-4, a member of the cytokine-inducible SH2-containing protein family, whose products are potential modulators of cytokine signaling. Abnormal cytokine modulation in mood disorders has been suggested by several studies [Rappaport and Manji, 2001; Middle et al., 2000; Tsai et al., 1999; Iancu et al., 1997]. In order to investigate the potential contribution of genetic variation in CIS4 to BPAD susceptibility, we have assembled a list of 21 SNPs from the public databases that map near CIS-4, according to the December 2001 assembly of the draft human genome sequence. CIS-4 is an intronless gene with a single 1608 basepair exon. The goal is to cover the promoter

Abstracts

region, exon, and 30 untranslated region with a set of markers that display a moderate degree of intermarker linkage disequilibrium (LD), then test these markers for association with BPAD. We have validated 19 SNPs in a sample of 20 founders from Caucasian CEPH pedigrees. Genotyping was accomplished using template-directed dye-terminator incorporation with fluorescence-polarization detection (TDI-FP), a method that performs well in our hands [Akula et al., 2002]. Four SNPs performed well in the TDI-FP assay and were polymorphic at a minor allele frequency of at least 10%. These 4 SNPs were genotyped in an additional 93 unrelated Caucasian CEPH founders, linkage disequilibrium between adjacent markers was estimated using GOLD (Abecasis et al., 2000). Most adjacent markers were in perfect LD, but 2 markers, spaced approximately 2 kb apart, were in moderate LD (D0 ¼ 0.38) with each other. These SNPs have been genotyped in a panel of 93 BPAD probands assembled from the Johns Hopkins/Dana Foundation pedigree collection [Simpson et al., 1993]. No significant differences in frequencies were detected, but we need to study additional markers in order to confidently exclude CIS-4 as a positional candidate gene for BPAD. P140 NO ASSOCIATION BETWEEN THE APOE GENE AND AUTISTIC DISORDER Raiford KL,1 Shao Y,1 Allen IC,1 Menold MM,1 Cuccaro ML,1 Gilbert JR,1 Wright HH,2 Abramson RA,2 Vance JM,1 and Pericak-Vance MA1 1 Center for Human Genetics, Duke University Medical Center, Durham, NC (2) University of South Carolina, Columbia, South Carolina Autistic Disorder (AutD) is a neurodevelopmental disorder characterized by stereotypic and repetitive behavior and interests, together with social and communicative deficiencies. Peak linkage/association scores on several genomic screens indicate the presence of an autistic disorder susceptibility locus on chromosome 19p13.2q13.4. The apolipoprotein E (APOE) gene on chromosome 19 encodes for a protein, apoE, whose different isoforms (-E2, -E3, -E4) influence neuronal growth, participates in lipid transport and metabolism, repair, growth, and maintenance of axons and myelin during neuronal development. The APOE gene competes with the reelin gene for VLDL/APOER2 receptor binding. A previous report found evidence for an association between AutD and the reelin gene. In addition, it has been suggested that the APOE-2 allele has a protective effect against infertility and miscarriage in AutD families. Based on these data we examined APOE as a candidate gene in AutD. We tested for genetic association using family-based association methods in a data set of 163 multiplex Duke and AGRE AutD families (2 or more AutD affecteds per family) and 159 singleton Duke AutD families (1 AutD affected per family). We saw no significant evidence that AutD is

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associated with the APOE gene (PDT P ¼ 0.92; TRANSMIT P ¼ 0.52). Analysis of APOE promoter SNPs 113cg, 219gt, 427ct, 491at, and 5361ct is in progress and will be incorporated in the analysis in order to fully evaluate the APOE gene. P141 TUMOR NECROSIS FACTOR-ALPHA GENE PROMOTER POLYMORPHISM IN SCHIZOPHRENIA Rybakowski F,1 Czerski P,2 Kapelski P,3 Godlewski S,2 Dmitrzak-We˛glarz M,2 Hauser J,2,3 and Rybakowski J3 1 Department of Child and Adolescent Psychiatry, University of Medical Sciences, Poznan, Poland 2 Laboratory of Psychiatric Genetics, University of Medical Sciences, Poznan, Poland 3 Department of Adult Psychiatry, University of Medical Sciences, Poznan, Poland An association of Tumor Necrosis Factor alpha (TNF alpha) polymorphism (G308A) and schizophrenia was recently reported, with TNF 2 allele, responsible for higher expression of TNF alpha being more prevalent in schizophrenic patients. In the present study, this polymorphism was studied in 241 patients with schizophrenia, diagnosed with SCID and 327 healthy controls. In our highly homogenous sample the case/ control study design was used. We did not observe an association of any of the TNF alleles with schizophrenia (P ¼ 0.8). In both genders the differences in the frequency of alleles were not significant, for males P ¼ 0.5; for females P ¼ 0.3. The frequency of genotypes in schizophrenia patients and controls were respectively: (TNF1/TNF1 76.8% vs. 69.7%, TNF1/TNF2 21.2% vs. 27.5%, TNF2/TNF2 2.1% vs. 2.8%), which is an insignificant difference. Our results do not confirm the contribution of the TNF alpha gene polymorphism to the susceptibility to schizophrenia. P142 FAMILY-BASED ASSOCIATION STUDIES OF TRACE AMINE RECEPTOR GENES ON 6q23.3 IN BIPOLAR AFFECTIVE DISORDER Schumacher J,1 Diaconou C,2 Abou Jamra R,1 Kaneva R,1 Hua Y,1 Schulze TG,3 Mu¨ller DJ,4 Gross M,5 Ohlraun S,6 Golla A,7 Rietschel M,6 Cichon S,8 No¨then MM,8 and Propping P1 1 Institute of Human Genetics, University of Bonn, Germany 2 Institute of Virology, University of Bucharest, Romania 3 Department of Psychiatry, University of Chicago, Chicago, Illinois 4 Mental State Hospital Bonn, Germany 5 Department of Psychiatry, University of Bonn, Germany 6 Central Institute of Mental Health, Mannheim, Germany 7 Institute of Medical Biometry, Informatics, Epidemiology (IMBIE), University of Bonn, Germany 8 Department of Medical Genetics, University of Antwerp (UIA), Belgium

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There is evidence suggesting a role of trace amines (TA) in the etiology of bipolar affective disorders (BPAD). A functional deficiency of TA has been proposed as a potential etiological factor in depression, increased levels of TA were found to be associated with manic phases of BPAD. The genes for two trace amine receptors, TA-1 and TA-4, are both located on chromosome 6q23.2. Interestingly, this particular chromosomal region has shown evidence for linkage to BPAD in a genome-wide screen [Cichon et al., 2001]. This prompted us to search for genetic variants in the TA-1 and TA-4 genes and test them for association with BPAD. Systematic sequencing of the TA-1 and TA-4 genes in 96 control individuals identified two common SNPs in the TA-4 receptor gene (914A/G and 993A/G) and one in the TA-1 receptor gene (1212A/G). TDT analysis of the three SNPs was performed in 118 parent-offspring triads that were partially derived from the genome screen sample. No association between the SNP in the TA-1 receptor gene and BPAD was found. However, we observed a preferential transmission of the 914G allele of the TA-4 receptor gene (P ¼ 0.014) and a non-significant trend of the 993G allele (P ¼ 0.06). Replication is clearly necessary to support a possible role of the TA-4 receptor gene in BPAD. P143 ASSOCIATION STUDY BETWEEN TWO CANDIDATE GENES, SERT AND INPP1 AND BIPOLAR DISORDER POLYMORPHISM IN 120 TRIADS WITH SARDINIAN ANCESTRY Severino G, Chillotti C, Ardau R, Quesada G, Congiu D, Piccardi MP, Squassina A, and Del Zompo M. Department of Neurosciences ‘‘B. B. Brodie’’, University of Cagliari, Italy. The aim of our study was to identify genes predisposing to Bipolar Disorder (BP) using linkage and association studies. In a sample of 120 triads we analyzed a possible association between genes coding for serotonin transporter (SERT) and inositol polyphosphate-1-phosphatase enzyme (INPP1), and some clinical variables of patients affected by BP. We selected 120 probands with parents alive, unrelated and with at least a two-generation Sardinian ancestry. We collected a sample of 109 BPI probands and 11 BPII. Diagnosis was made based on Research Diagnostic Criteria (RDC) and each participant signed the consent form. Statistical analysis was performed using the ‘‘TDT’’ (Transmission Disequilibrium Test) and ETDT program version 1.1. Clinical variables were examined using Mann-Whitney and Chi-square tests and SPSS statistical program version 10.0. Demographic-clinical variables examined included sex, BPI and BPII diagnosis, age at onset, number of manic and hypomanic episodes, number of depressive episodes and hospitalizations, diagnosis at first episode, history of suicide attempts, family history of affective disorder. TDT did not show any statistically significant association between some of clinical vari-

ables above and candidate genes examined. Association data for clinical variables studied gave negative results, but data analysis is not complete yet. We believe the precise characterization of psychopatology of the probands is of great importance to define new phenotypes good for molecular genetic studies.

P144 ASSOCIATION STUDY OF CANDIDATE GENES FOR SUSCEPTIBILITY TO SCHIZOPHRENIA AND BIPOLAR DISORDER ON CHROMOSOME 22q13 Severinsen J,1 Binderup H,1 Mors O,2 Wang AG,3,4 Vang M,3 Murray V,5 Muir W,6 McKee I,7 Kruse TA,8 Blackwood D,6 Ewald H,2 and Børglum AD1 1 Institute of Human Genetics, University of Aarhus, Denmark 2 Institute for Basic Psychiatric Research, Department of Psychiatric Demography, Psychiatric Hospital in Aarhus, Denmark 3 Department of Psychiatry, National Hospital, Torshavn, Faroe Islands. 4 Copenhagen University Hospital, Denmark 5 Gartnavel Royal Hospital, Glasgow, Scotland, UK 6 Department of Psychiatry, Royal Edinburgh Hospital, Edinburgh, Scotland, UK 7 Hairmyres Hospital, East Kilbride, Scotland, UK 8 Department of Clinical Biochemistry and Genetics, Odense University Hospital, Denmark Chromosome 22q is suspected to harbor risk genes for schizophrenia as well as bipolar affective disorder. This is evidenced through genetic mapping studies, investigations of cytogenetic abnormalities, and direct examination of candidate genes. In a recent study of distantly related patients from the Faroe Islands we have obtained evidence suggesting two regions on chromosome 22q13 to potentially harbor susceptibility genes for both schizophrenia and bipolar affective disorder. We have selected a number of candidate genes from these two regions for further analysis, including the neurogene WKL1, in which a missense mutation recently has been suggested to cause catatonic schizophrenia in a German family. The selected candidate genes were analyzed by a combination of database search and direct sequencing in a subset of the patients from the Faroe Islands in order to identify SNPs in the coding regions and in regions possibly affecting expression level and splicing of the genes. For efficient detection of the SNPs identified multiplex PCR and SBE (single base extension) reactions were developed. Subsequently the SNPs were analyzed in the total Faroese sample of distantly related patients and unrelated controls, and in a Scottish case-control sample comprising 200 schizophrenics, 200 bipolar patients and 200 controls. None of the investigated SNPs have so far showed strong evidence of association to either bipolar disorder or schizophrenia.

Abstracts

P145 LACK OF ASSOCIATION BETWEEN 5HT 2A SEROTONIN RECEPTOR GENE POLYMORPHISM AND ANOREXIA NERVOSA Slopien A,1 Rybakowski F,1 Dmitrzak-We˛glarz M,1,3 Czerski P,2,3 Rajewski A,1 and Hauser J2,3 1 Department of Child and Adolescent Psychiatry, University of Medical Sciences, Poznan, Poland 2 Department of Adult Psychiatry, University of Medical Sciences, Poznan, Poland 3 Laboratory of Psychiatric Genetics, University of Medical Sciences, Poznan, Poland Serotonin is a neuromediator which plays an important role in the regulation of food intake, sexual and social behavior, as well as personal characteristics. In 1997 Collier et al. reported an association between a polymorphism of the promoter region of the 5HT2A serotonin receptor gene and anorexia nervosa. The polymorphism is characterized by a guanine to adenine substitution in position 1438 of the promoter region. So far known, this polymorphism has no impact on level of protein expression. We studied 67 patients with anorexia nervosa and 114 women from a control group (blood donors and students). The polymorphism was genotyped with the use of a PCR-RLFP method. There were no statistically relevant differences of allele and genotype frequencies between patients with anorexia nervosa and controls. In conclusion, we could not replicate the previously reported association of the 5HT2A receptor promoter polymorphism and anorexia nervosa. P146 COMPREHENSIVE MUTATION SCANNING OF RAR/RXR AND VITAMIN D RECEPTOR GENES IN PATIENTS WITH SCHIZOPHRENIA AND OTHER PSYCHIATRIC DISEASES Sommer SS,1 Feng J,1 Chen J,1 Yan J,1 Craddock N,2 Jones I,2 Cook E Jr,3 Goldman D,4 and Heston LL5 1 Department of Molecular Genetics, City of Hope National Medical Center, Duarte, California 2 Division of Neuroscience, University of Birmingham, Queen Elizabeth Psychiatric Hospital, Birmingham, UK 3 Department of Psychiatry, University of Chicago, Chicago, Illinois 4 Department of Psychiatry, NIAAA, NIH, Bethesda, Maryland 5 Department of Psychiatry, University of Washington, Seattle, Washington Retinoic acid receptors (RAR), retinoid X receptors (RXR) and the Vitamin D receptor (VDR) are involved in the regulation of brain function. Defects in these receptors may contribute to schizophrenia or other psychiatric diseases. To test this hypothesis, the RAR and RXR genes (RARalpha, beta, gamma & RXRalpha, beta, gamma) and VDR gene were scanned by DOVAM-S (Detection of Virtually All Mutations-SSCP), a robotically enhanced multiplexed scan-

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ning method that is a highly sensitive modification of SSCP.196 subjects (including 100 patients with schizophrenia and pilot experiment in patients with bipolar disorder,24 autism,24 ADHD,24 and alcoholism (24)) were scanned in each gene. A total of 3.2 megabases of genomic sequences were scanned. Seven VAPSEs (Variants Affecting Protein Structure or Expression) and 24 non-VAPSEs were identified. The data define structural variants that may be relevant to disease. Only one gene (RARbeta showed some potential relationship to schizophrenia. One VAPSE, N307T in RARbeta gene is at a residue that is highly conserved during evolution, e. g. N is conserved in the five available mammalian and bird species and fish, hinting that these sequence changes will be of functional significance. A further casecontrol study showed a trend that the frequency of N307T is higher in schizophrenia than that in ethnically matched controls (4/498 vs 1/509). Although no unequivocal associations were found, some variants, especially those at highly conserved residues, merit further analysis with larger samples. P147 THE mu OPIOID RECEPTOR GENE AS A CANDIDATE FOR THE STUDY OF OBSESSIVE COMPULSIVE DISORDER WITH AND WITHOUT TICS Urraca N,1 Camarena B,1 Go´mez-Caudillo L,2 Esmer MC,3 and Nicolini H1 1 Department of Genetics, Instituto Nacional de Psiquiatrı´a Ramo´n de la Fuente Mun˜iz, Mexico City, Mexico 2 Department of Biostatistics, Instituto Nacional de Psiquiatrı´a Ramo´n de la Fuente Mun˜iz, Mexico City, Mexico 3 Department of Genetics, Instituto Nacional de Pediatrı´a, Mexico City, Mexico Obsessive-Compulsive disorder (OCD) is a complex psychiatric disease characterized by recurring obsessions or compulsions that cause significant distress to the patient. The etiology of this disorder remains largely unknown, although a genetic component has been suggested based on family, twin, segregation analysis and association studies. Many candidates genes have been evaluated based on a possible serotoninergic and dopaminergic brain disfunction. We postulate the mu opioid receptor gene as a candidate because some observations support a role of the opioid system in OCD. The opioid antagonist, naloxone, rapidly exacerbates OCD symptoms and the opioid agonist, tramadol, was reported to be effective in the treatment of some patients. We studied two single nucleotide polymorphisms (C17T and A11G) in 51 trios with OCD. Genotyping was analyzed with haplotype relative risk (HRR) and transmission desequilibrium test (TDT). The allelic variant þ 17T of the C17T polymorphism had a low frequency (1%) in our population that did not allow for statistic analysis. However, for the allelic variant þ G of the A118G polymorphism we were able to perform statistical

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comparisons. We looked for differences in clinical variables as gender (29 males and 22 females), comorbid depression (n ¼ 7), tics (n ¼ 17) and the type of obsessions and compulsions. Our results showed a trend toward significance (P ¼ 0.065) for TDT in patients with comorbid tics. After subrouping this sample, we ended up with decreased statistical power due to sample size. But, still it is an interesting finding that should be tested in a larger samples of OCD patients with tics. P148 LACK OF ASSOCIATION BETWEEN CLOMIPRAMINE RESPONSE TO OBSESSIVE COMPULSIVE DISORDER AND ALLELIC VARIATION IN THE 5-HT2A RECEPTOR AND COMT GENE Vallada H, Shavitt RG, Meira-Lima IV, Ikenaga E, Miguita K, Belloto C and Miguel EC Department of Psychiatry, Sa˜o Paulo Medical School, Brasil The efficacy of the tricyclic antidepressant clomipramine to the pharmacotherapy of obsessive-compulsive disorder (OCD) has been established by several clinical trials and pharmacogenetic factors might influence its antiobsessional response. This study investigates the association between the C516T variant in the serotonin 2A receptor (5-HT2A) and the Val-158-Met substitution in catechol-O-methyltransferase (COMT) genes and OCD patients under clomipramine treatment. The total of forty-one OCD patients participated in a clomipramine clinical trial, of which 27 patients (66%) responded and 14 (33%) did not respond to the clomipramine according to the clinical global impressions (CGI) and to the Yale-Brown Obsessive Compulsive Scale (YBOCS). The analysis between the responder and non-responder patients did not show statistical differences on genotipic and allelic frequencies neither for the C516T polymorphism in the 5HT2A gene (genotype: w2 ¼ 1.4, 2df, P ¼ 0.4/allele: w2 ¼ 0.1, 1df, P ¼ 0.7) nor for the Val-158-Met variant in the COMT gene (genotype: w2 ¼ 0.14, 2df, P ¼ 0.7/allele: w2 ¼ 2, 1df, P ¼ 0.3). These results did not support the hypothesis that genetic variations in the 5HT2A and COMT genes may influence the individual response to clomipramine in OCD patients. This work was supported by FAPESP # 99/ 12205-7. P149 IS CASPR2 A GENE FOR GILLES DE LA TOURETTE SYNDROME? *Verkerk AJMH,1 Mathews CA,2 Joosse M,1 Eussen B,1 Willemsen R,1 Peles E,3 Heutink P,1 and Oostra BA1 1 Erasmus Medical Center, Rotterdam, The Netherlands 2 University of California, San Diego, San Diego, California 3 The Weizmann Institute of Science, Israel Gilles de la Tourette Syndrome (GTS) is an inherited neuropsychiatric disorder characterized by repeated involuntary motor and vocal tics. A number of patients also suffer from

coprolalia (shouting of obsceneties) and/or echolalia (constantly repeating words of other people). Different kinds of obsessive behaviour are part of the GTS phenotype. GTS is a complex disorder and it is thought to be the result of a combined action of a number of (aberrant or dysfunctional) genes. Until now linkage analysis has pointed to a number of chromosomal locations, but without a clear point of focus. We are focussing on a GTS family with a complex insertion/ translocation of chromosomes 2 and 7. The affected father and two affected children share a breakpoint on chromosome 7q35-36. The breakpoint interupts the Contactin associated protein 2 or Caspr2 gene between exons 8 and 9. This 25 exon gene has recently been described and is expressed in the peripheral and central nervous system. It is a membrane protein that is located in the nodes of Ranvier of axons and is thought to be associated with shaker like potassium channels, which in their turn are involved in the repolarization of action potentials. Caspr 2 is thought to be involved in the distribution and relocation of these K þ -channels to the juxtaparanodal region at the nodes of Ranvier during development. We hypothesize that disruption or decreased expression of Caspr2 could lead to a disturbed distribution of the K þ channels in the nervous system, having an influence on conduction and/or repolarization of the action potential in certain parts of the brain that are sensitive to these kind of changes. P150 NO ASSOCIATION BETWEEN SCHIZOPHRENIA AND A NOVEL TRINUCLEOTIDE REPEAT POLYMORPHISM IN ATP6B2 Webb BT,1,3 Straub RE,4 Wormley B,2,3 York TP,1,3 Kendler KS,1,2,3 Riley BP,1,2,3 and Neale MC1,2,3 1 Departments of Human Genetics and 2Psychiatry, 3Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, Richmond, Virginia 4 Clinical Brain Disorders Branch, IRP, NIMH, NIH, Bethesda, Maryland ATP6B2 is a subunit of a multimeric ATPase that functions as a vacuolar proton pump (VPP). One function is the generation a proton gradient across the synaptic vesicle membrane. Some psychoactive compounds including MDMA and amphetamine are thought to work in part by depleting vesicles through disruption of the proton gradient. This subunit maps to 8p21, an interval that has shown linkage to schizophrenia in several samples. Previous findings include a P-value of 0.00004 with D8S258 using affected sib-pair analysis in the Maryland Family sample and a single-point HLOD of 3.65 at the microsatellite marker in the Lipoprotein Lipase (LPL) gene in the Irish Study of High-Density Schizophrenia Families (ISHDSF). ATP6B2 is between markers LPL and D8S258, an interval of less than 1 megabase. Recent independent microarray studies reported altered expression in schizophrenia for separate subunits of the VPP complex:

Abstracts

ATP6B2 (56/58 kD subunit) and ATP6C (42-kD subunit), respectively. Based on positional, functional and expression evidence, we tested ATP6B2 as a candidate for schizophrenia. We defined the genomic structure, identified a trinucleotide repeat polymorphism in the promoter, and performed an association study with schizophrenia. The gene has 15 exons covering approximately 22.7 kilobases and at least 2 splice variants. There is a GAA repeat approximately 600 base pairs upstream of the start of transcription. This polymorphism has two common alleles and was genotyped in the IHDS. No evidence for an association between the trinucleotide repeat and schizophrenia was found. It remains to be seen whether this polymorphism is functional or if other polymorphisms in ATP6B2 are associated with schizophrenia.

Poster Session 7: Neurological and Psychiatric Childhood Diseases P151 NEUROPSYCHOLOGICAL PROFILE OF CHILDREN WITH DIFFERENT DYSFUNCTIONS AND BEHAVIORAL PROBLEMS, BY MEANS OF THE ‘NEPSY’ Aguilar-Alonso A1 and Sa´nchez-Lancis E2 1 Department of Personality, Assessment and Psychological Treatment, University of Barcelona (UB), Spain 2 Department of Psychiatry, Hospital of Saint John of God, Barcelona, Spain ‘NEPSY’ A Developmental Neuropsychological Assessment0 (M. Korkman, U. Kirk, & S. Kemp, 1998) is a new tool for developmental children assessment published by Psychological Corporation. It permits the evaluation of five complex cognitive multi-factorial domains, that are composed of more than 26 subtests evaluating possible contributory factors of a primary deficit, and thus understanding the selective subcomponents of each of the cognitive domains that may be differentially affected. Everything is very important to determine the developmental state of the children, and to know if all it is agree with the level reached by other children of same age. In our research we present the neuropsychological profile of 39 children, evaluated by means of a Spanish version of the NEPSY and by means of the WISC-R, because the mentioned Spanish version of the NEPSY is still in process of psychometric elaboration. The sample is composed by 40 children of two genders, previously diagnosed with psychosis, 9 autism, 5 cerebral traumatism, 7 affective dysfunctions, 9 mentally retarded, 5 school delay (4) and anorexia1 In the section ‘Results,’ we present the performance profiles and statistics of these different groups of children, also the correlate between NEPSY and WISC-R, and a principal components analysis of the subjects, by means of the trans-

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posed matrix of their individual punctuations in the subtests of both bateries (Q method of Cattell). P152 CYTOGENETIC EVALUATION OF INDIVIDUALS WITH MENTAL RETARDATION Anupam Kaur B, Mahajan S, and Rup Singh J Centre For Genetic Disorders, Guru Nanak Dev University, Amritsar, India The incomplete development of mental capacities and associated behavioural abnormalities is referred to as mental retardation. It is single largest neuropsychiatry disorder in every civilised society affecting 2.5–3.0% of the total population. Chromosomal abnormalities are an important cause of mental retardation. Chromosomal investigations were carried out on 156 mentally subnormal that were referred to the centre for Genetic Disorders, Guru Nanak Dev University, Amritsar, India, during 1996 to 2002. These cases were referred mainly as Suspected Down’s syndrome, delayed milestones and mental retardation, etc. The age group of the patients ranged from 1 month to 18 years. Interestingly maximum number of patients (27.5%) was the firstborn and the average maternal age was 27.8 years. In the present study free trisomy 21 was found to be the most frequent autosomal aberration, both amongst males and females (39.7% males: 18.5% females). Cytogenetic analysis revealed trisomy 21, in 58.3% cases and translocations in 2.5% cases. These include 45, XY, þ t (13; 14), 46, XY, þ t (14: 21), 45, XX, þ t (14; 21) and 46, XX, þ t (14; 21) karyotypes. P153 PREFERENTIAL TRANSMISSION OF THE 148 BASE-PAIR DOPAMINE D5 RECEPTOR (DRD5) MICROSATELLITE REPEAT POLYMORPHISM IN ATTENTION DEFICIT HYPERACTIVITY DISORDER (ADHD) AND PERFORMANCE ON A CONTINUOUS PERFORMANCE TEST (T. O. V. A.) Bachner-Melman R,1 Manor I,2 Eisenberg J,1 Rosolio N, Tyano S,2 and Ebstein RP1 1 S. Herzog Hospital, Jerusalem, Israel 2 Geha Mental Health Center, Petak Tikvah, Israel Genes coding for dopaminergic neurotransmission are likely candidates for association studies in ADHD since stimulants such as methylphenidate are clinically efficacious in treatment of this disorder. Indeed, a recent meta-analysis demonstrated a small but overall significant association between the DRD4 receptor and ADHD. Other dopaminergic genes including the dopamine transporter and a DRD5 148 base-pair microsatellite polymorphism have also been shown in some studies to confer risk for ADHD. In the current study we genotyped 164 complete triplets for the DRD5 polymorphism and confirmed preferential transmission (TDT w2 ¼ 8.41, P ¼ 0.0037) of the 148 base-pair microsatellite repeat in 126 informative transmissions (95 Transmitted

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& 59 non-Transmitted 148 bp alleles). Additionally, on 132 subjects we had information regarding their performance on a continuous performance test (T. O. V. A.). Paradoxically, ADHD children carrying the preferentially transmitted 148 bp allele had significantly less errors of omission (a measure of inattention) compared to probands without the 148 bp allele (Kruskal-Wallis Test: w2 ¼ 4.43, P ¼ 0.035, N ¼ 132). Altogether, for 90 ADHD children we have compared genotype information and T. O. V. A. scores for three genetic polymorphisms (DRD5, DRD5 and MAO A). Univariate analysis demonstrated a significant three-way interaction between these genes and T. O. V. A. Variability (F ¼ 3.98, P ¼ 0.049). Our results suggest therefore that several genes of small effect size are contributing risk for ADHD and, additionally, that neuropsychological measurements of performance provide some insight into the mechanisms by which common genetic polymorphisms may be mediating behavioral disorders. P154 SIGNIFICANT EVIDENCE FOR LINKAGE OF ATTENTION-DEFICIT HYPERACTIVITY DISORDER TO THE CHROMOSOME 15q REGION Barr CL,1,2 Wigg K,1 Feng Y,1 Anderson B,2 Crosbie J,2 Roberts W,2 Malone M,2 Ickowicz A,2 Schachar R,2 Tannock R,2 Lovett M,2 Humphries T,2 and Kennedy JL3 1 The Toronto Western Hospital, Canada 2 The Hospital for Sick Children, Toronto, Canada 3 The Centre for Addiction and Mental Health, Clarke Division, Toronto, ON, Canada Strong support for genetic overlap of reading disabilities (RD) and symptoms of attention-deficit hyperactivity disorder (ADHD) is derived from twin studies, in particular the dimension of inattention and RD. A number of genetic linkage findings have been reported for RD (6p, 6q, 2p, 1p, 15q, 18p) and the 6p and 15q regions have also been reported to be linked to the ADHD phenotype in families with RD that are linked to these two regions. We investigated the overlap of these two phenotypes in the 15q region using two samples of nuclear families, one ascertained through a proband with RD (n ¼ 88 families) and the other through a proband with ADHD (n ¼ 174 families). Families referred for the RD study were prescreened for a diagnosis of ADHD and subjects with evidence for ADHD referred to the ADHD study. This resulted in the RD sample having significantly lower ADHD symptoms for the probands (mean Parent Conner’s T scores 57.47 for inattention and 52.06 for hyperactivity/impulsivity) compared to the ADHD sample (70.89 for inattention and 73.45 for hyperactivity/impulsivity). We found significant evidence for linkage in the ADHD sample to the marker D15S146 for the DSM-IV ADHD phenotype (w2 ¼ 7.336, P ¼ 0.007) using the transmission disequilibrium test. However there was no evidence for linkage to the reading phenotypes of phonological awareness, decoding, or word

identification using a quantitative approach. In the RD sample there was no evidence for linkage to the reading phenotypes or to symptoms of ADHD as measured by Parent Conner’s T scores. The failure to find evidence for linkage to the reading phenotypes in either sample may result from low power or may suggest that the linkage finding on 15q is more closely related to ADHD phenotype. P155 DOPAMINE TRANSPORTER GENE (DAT1) POLYMORPHISM AND EXECUTIVE FUNCTION IN CHILDREN WITH ADHD Mbekou V, Grizenko N, *Ben Amor L, Lageix P, Baron C, Schwartz G, Ter Stepanian M and Joober R. Douglas Hospital Research Centre, McGill University, Montreal, Canada. The 30 end 10-repeat (480 bp) allele of the dopamine transporter gene (SLC6A3) has been associated with the risk of developing Attention Deficit Hyperactivity Disorder (ADHD) in children. Dopamine plays an important role in regulating various prefrontal mediated cognitive functions some of which have also been shown to be impaired in children and adults with ADHD. The purpose of this study is to investigate the relationships between the allelic variation of SLC6A3 and executive function performance in children with ADHD. SLC6A3 was genotyped in 54 children diagnosed with ADHD according to DSM-IV criteria. Three measures of executive function were also administered to these children: the Wisconsin Card Sorting Test (WCST), the Tour of London (TL) and the Self Ordered Pointing Task (SOPT). Compared to subjects with at least one 9-repeat allele, carriers of the 10/10 genotype made significantly less errors on the SOPT (25 and 28 subject respectively, t (1, 51) ¼ 2.27; P ¼ 0.02) and tended to make fewer perseverative errors (21 and 24 subjects respectively, t (1, 43) ¼ f {1.86, P ¼ 0.06} on the WCST. No differences on the scores of the TL were observed between the two groups. Contrary to our expectations, the 10/10 genotype (risk genotype for ADHD) was associated with better performance on executive function tasks in this sample of ADHD children. This apparent contradiction may be due to genetic heterogeneity in the ADHD syndrome, with a subgroup presenting normal executive function and increased risk to ADHD attributable to the 10 repeat allele. P156 PERINATAL COMPLICATIONS IN ATTENTION DEFICIT HYPERACTIVITY DISORDER (ADHD): SHARED OR NON-SHARED ENVIRONMENTAL FACTORS? Ben Amor L, Grizenko N, Ter Stepaninan M, Lageix P, Baron C, Schwartz G, Mbekou V, and Joober R Department of Psychiatry, McGill University, Douglas Hospital Research Centre, Montreal, Canada

Abstracts

Genetic epidemiological studies indicated that non shared environmental factors but not the shared ones are implicated in ADHD. Pregnancy, labor/delivery, and neonatal complications (PLDNC) were associated with ADHD, but there is no investigation assessing the shared or non-shared nature of these factors. We hypothesize that children with ADHD differ from their non-affected siblings with regard to certain pregnancy, labor/delivery, and neonatal complications. These would represent non-shared environmental factors. Aims: to identify the putatively non-shared PLDNC in ADHD children compared to their non-affected siblings and to determine if these factors are associated with ADHD phenotype. Methods: As part of an ongoing pharmacogenetic study (2 week placebo-controlled double-blind crossover trial with methylphenidate) 65 children diagnosed with ADHD (DSMIV) and 50 non-affected siblings were evaluated with regard to PLDNC, using the Kinney McNeil questionnaire and the McNeil Sjostrom scale. Results: ANOVA between probands and siblings (PLDNC scores at different developmental periods -pregnancy, labor/delivery, neonatal-was the dependent variable) revealed a significant effect of the developmental period (F4, 392 ¼ 4.88, P < 0.000) and a significant interaction between the groups (affected, non-affected) and the developmental period (F4, 392 ¼ 2.61, P ¼ 0.03). ADHD children have significantly more neonatal complications than their non-affected siblings (P ¼ 0.03). ADHD children with neonatal complications, compared to those without, have higher scores on Continuous Performance Test Overall Index and on CBCL total and externalizing but not internalizing scores (P < 0.05). Conclusion: Among PLDNC, only neonatal complications were significantly increased in ADHD children compared to their non-affected siblings. These neonatal complications were associated with higher levels of severity in ADHD children. P157 LINKAGE AND ASSOCIATION STUDIES OF THE ALPHA 7 NICOTINIC ACETYLCHOLINE RECEPTOR LOCUS AND THREE GABA (A) RECEPTOR SUBUNIT GENES ON CHROMOSOME 15q11-q13 IN AUTISM Betancur C Inserm U513, Cre´teil, France The results of family and twin studies suggest a strong genetic component in the etiology of autism, but the implicated genes remain unknown. Chromosome 15q11-q13 is the most common site of chromosomal abnormalities associated with autism; these findings, together with results of association and linkage studies suggest that this region may contain a susceptibility gene to autism. We studied a cluster of genes located on chromosome 15q11-q13, coding for three subunits of the GABA (A) receptor, alpha 5 (GABRA5), beta 3 (GABRB3), and gamma 3 (GABRG3), in 152 families, consisting of 56 affected sib pairs and 96 parent-offspring trios,

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recruited by the Paris Autism Research International Sibpair (PARIS) Study. Significant linkage disequilibrium has been previously reported between GABRB3 markers and autistic disorder, although subsequent studies provided conflicting evidence. In addition, we studied the nicotinic receptor alpha 7 subunit gene (CHRNA7), located on 15q13.2, in the same family data set. We genotyped 18 microsatellite markers spanning the 15q11-13 region, including intragenic markers for the three GABA subunits and a 2-bp deletion within the duplicated exon 6 of CHRNA7. We found no evidence of linkage or linkage disequilibrium at any of the markers tested, indicating that the GABRA5, GABRB3 GABRG3, and CHRNA7 genes are unlikely to play a major role in the etiology of autism in our data set.

P158 COGNITIVE PROFILE OF CHILDREN WITH VELO-CARDIO-FACIAL SYNDROME (VCFS) Campbell LE,1 Stevens AF,1 Morris R,1 Karmiloff-Smith A,2 Simonoff E,1 Owen MJ,3 Murphy DGM,1 and Murphy KC4 1 Institute of Psychiatry, King’s College London, UK. 2 Institute of Child and Health, University College London, UK 3 University of Wales College of Medicine, Cardiff, UK 4 Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin, Ireland VCFS, a genetic disorder characterised by congenital heart disease, borderline learning disability and schizophrenia, is associated with variably sized deletions of 22q11. In this study, our aim was to characterise the cognitive profile in VCFS children. We recruited 8 children (6–16 years) and 8 age matched sibling controls. The VCFS group had a mean full scale IQ of 67.50 (SD: 6.74) compared with 101.88 (SD: 13) for the control group (P < 0.001). The mean verbal IQ of the VCFS group was found to be 70 (SD: 8.94) while the performance IQ was 68.50 (SD: 6.35) (P < 0.67). The control group had a mean VIQ of 104.5 (SD: 12.13) and a PIQ of 98.25 (SD: 13.16) (P < 0.13). The factor-based index scores indicated that VCFS children had the highest mean score on processing speed (PS) (79.5, SD: 13.22) and freedom from distractibility (FD) (77, SD: 6.48) while perceptual organisation (PO) (67.5, SD: 8.84) and verbal comprehension (VC) (71, SD: 9.90) were lower. The control group had the highest mean score on PS (111.86, DS: 15.13) and VC (106.29, SD: 12.87) and lowest on PO (98.57, SD: 14.38) and FD (98.57, SD: 8.60). The children with VCFS in this study had a mean IQ score at the higher end of the mildly mentally retarded range. In this preliminary report, we found no evidence of a significant verbal/performance IQ discrepancy reported in previous studies of VCFS children. We aim to follow up these children as part of a larger cohort to identify early precursors for the development of schizophrenia as they progress into adulthood.

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P159 THE SEROTONIN TRANSPORTER: ASSOCIATION STUDIES IN THE IRISH POPULATION Conroy J, Gallagher L, Kearney G, Fitzgerald M, and Gill M Departmant of Genetics/Department of Psychiatry, Trinity College, Dublin, Ireland The role of the serotonin transporter gene (5-HTT) in autism has been widely investigated. Two polymorphisms, an insertion in the promoter region and a 12 repeat allele in a variable nucleotide tandem repeat (VNTR) in intron 2, drive higher expression of the 5-HTT gene. Four studies have shown nominally significant transmission disequilibrium of the 5HTT gene in autism, while 3 studies have reported no linkage disequilibrium. This study investigated the role of 5-HTT in the genetically homogeneous Irish population. 84 families were genotyped for the 5-HTT promoter and VNTR variants, and 78 families were genotyped for a variant in the 30 untranslated region (30 UTR) of the gene. Transmission disequilibrium testing (TDT) and haplotype based haplotype relative risk (HHRR) analysis were undertaken. A trend towards preferential transmission of the short promoter (i. e. deletion) allele was observed although this did not reach statistical significance (P ¼ 0.0987). Neither TDT nor HHRR testing revealed any significant association with the VNTR or 30 UTR polymorphisms. Further studies are being undertaken on several recently described SNPs showing some evidence of association [Kim et al., 2002] and the results of these will be presented. P160 INHIBITORY CONTROL DEFICITS IN UNAFFECTED AND AFFECTED SIBLINGS OF ADHD PROBANDS: IMPLICATIONS FOR A COGNITIVE MARKER OF ADHD Crosbie J,1 Ornstein T,1 Barr C,1,2 Ickowicz, A,1 Tannock, R,1 Roberts W,3 Malone M,3 Kennedy JL,4 and Schachar R1 1 Department of Psychiatry, The Hospital for Sick Children, Toronto, Canada 2 Department of Psychiatry, The Toronto Western Hospital Research Institute, Ontario 3 Division of Neurology, The Hospital for Sick Children, Toronto, Canada 4 Neurogenetics Section, The Centre for Addiction and Mental Health, Clarke Division, Toronto, Canada Inhibitory control, as measured by the Stop Task Paradigm, consistently distinguishes ADHD children from normal controls (NC) and from children with comorbid disorders of ADHD (e. g., anxiety and conduct disorder). Recently, we reported that deficient inhibition may function as a cognitive marker for a subgroup of ADHD children with increased familial risk. We found that individuals with poor inhibitory control were significantly more likely (OR 3.9) to have a first degree relative with a history of ADHD. In order to further investigate the potential utility of inhibition control as a

cognitive marker for ADHD the present study examined inhibitory control functioning in ADHD probands and their affected siblings, ADHD probands and unaffected siblings, and NC (total N ¼ 93). We predicted that if inhibition is a marker for genetic risk: a) affected siblings would show similar deficits as their proband siblings, and b) that unaffected siblings would show poorer performance than normal controls, but less of a deficit than their affected siblings. The study showed both predictions to be true. A significant group effect (f ¼ 2.48, P ¼ 0.049) was found. Planned comparisons indicated that all ADHD groups differed significantly from NC. Affected siblings were not significantly different from their ADHD sibling (P ¼ 0.845). Unaffected siblings of ADHD probands did not differ significantly from their ADHD siblings (P ¼ 0.094) nor from NC (P ¼ 0.282); the trend in the data showed that they performed between these two groups, indicating that they were more impaired than the NC, but less impaired than their affected sibling. Groups did not differ in ‘‘go’’ responses suggesting that differences were due to inhibitory processes rather than an artifact of overall slowed reaction times. This finding provides further evidence of the utility of inhibition as a potential cognitive marker for the ADHD phenotype. P161 CLINICAL CHARACTERIZATION OF A CHROMOSOME 15 PHENOTYPE FOR AUTISM Cuccaro ML,1 Donnelly S,1 Ravan SA,2 Abramson RA,2 Wolpert C,1 Elston L,1 Wright HH,2 and Pericak-Vance MA1 1 Center For Human Genetics, Duke Medical Center, Durham, North Carolina 2 William S. Hall Psychiatric Institute, University of South Carolina, Columbia, South Carolina Autism (AutD) is a complex neurodevelopmental disorder. Epidemiologic and genetic analyses indicate that AutD is genetically heterogeneous and associated with a very wide range of clinical manifestations. Chromosomal region 15q11-q13 is one candidate region based on cytogenetic linkage and association findings. Ordered subset analysis (OSA) is an analytic method that uses a selected variable to identify a homogenous subset of individuals who contribute to linkage in a particular chromosomal region. Using a factor derived from restricted and repetitive behaviors as the covariate in OSA, a subset of 23 AutD families were identified as contributors to linkage on Chr 15 (OSA N ¼ 46; 23 sibpairs). We compared these Chr 15 AutD sibpairs with the remaining AutD sibpairs that did not show evidence for linkage across composite indices from the Autism Diagnostic Interview-R (ADI-R) and Vineland Adaptive Behavior Scales (VABS). Between group comparisons revealed that the OSA defined subset was more impaired on a measure of social functioning (VABS Socialization t ¼ 2.72, P ¼ 0.007). In addition the OSA defined AutD group showed a trend toward significance reflective of lower overall adaptive func-

Abstracts

tioning (Adaptive Behavior Composite t ¼ 1.91, P ¼ 0.058). The groups did not differ on either the ADI-R or VABS communication indices. These results are suggestive of a greater degree of social impairment in the OSA defined Chr15 AutD group. The VABS Socialization domain has been proposed as a quantitative index of social impairment in AutD. The results are consistent with the hypothesis that increased repetitive behavior exerts an effect on social and behavioral functioning. Additional efforts to investigate different phenotypic expression in AutD populations for application to genetic analysis will be extremely valuable in delineating the boundaries of AutD.

P162 SIGNIFICANT GENETIC ASSOCIATIONS BETWEEN TOURETTE SYNDROME AND DOPAMINERGIC GENES IN THE FRENCH CANADIAN POPULATION Dı´az-Anzaldu´a A, Dion Y, Chouinard S, Shevell M, and Rouleau GA. McGill University Health Centre, Montreal, Canada Tourette Syndrome (TS) is a genetically complex disorder for which no causative gene has been identified. Nevertheless, there are positive molecular and cytogenetic reports that, if confirmed, may lead to the identification of suceptibility genes. We searched for all previous positive findings of linkage or association between candidate genes and the strict diagnosis of TS. We tested the hypothesis that these particular candidate genes were associated with TS in 100 French Canadian nuclear families. We found alleles that were transmitted significantly more frequently than expected: the 7-repeat allele of the DRD4 exon 3 VNTR (w2 TDT ¼ 10.706, 1 df, P ¼ 0.0011), and the ‘‘high activity’’ alleles of the MAO-A promoter polymorphism (w2 TDT ¼ 7.124, 1 df P ¼ 0.0076). These data support the notion that these genes may confer an increased risk for developing TS and represents one of the first association findings for TS in the French Canadian population.

P163 FAMILY-BASED AND ASSOCIATION STUDIES OF MONOAMINE OXIDASE A AND ATTENTION DEFICIT HYPERACTIVITY DISORDER (ADHD): PREFERENTIAL TRANSMISSION OF THE LONG PROMOTER-REGION REPEAT AND ITS ASSOCIATION WITH IMPAIRED PERFORMANCE ON A CONTINUOUS PERFORMANCE TEST (T. O. V. A.) Ebstein RP,1 Manor I,2 Tyano S,2 Kotler M,3 BachnerMelman R,1 and Mel E1 1 Research Laboratory, S. Herzog Memorial Hospital, Jerusalem, Israel

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2

Geha Mental Health Center, Petak Tikvah, Israel Beersheva Mental Health Center, Faculty of Health Sciences, Ben Gurion University of the Negev, Israel 3

Monoamine oxidase A (MAO A) is located on the X chromosome and metabolizes biogenic amines including dopamine, norepinephrine and serotonin. A functional promoter-region polymorphism of this gene has been described that has been studied in a number of mental illnesses but not in attention deficit hyperactivity disorder (ADHD). In the current study, we examined the MAO A promoter-region polymorphism initially in 133 triads and observed preferential transmission of the long alleles from 74 heterozygote mothers to ADHD probands (w2 ¼ 4.37, P ¼ 0.036, df ¼ 1). We also examined the role of this polymorphism in a computerized continuous performance test, the T. O. V. A. Significant differences were observed on errors of commission (chi-square ¼ 7.021, P ¼ 0.008) and patients carrying the long MAO A allele made significantly more such errors. Errors of commission are a measure of impulsivity. However, following Ritalin (methylphenidate) administration the association between this polymorphism and errors of commission was markedly attenuated and no longer significant at the P < 0.05 level. We also analyzed the provisional association by the case-control design. A significant difference in allele frequency was observed between 110 male probands versus 202 male controls (Pearson w2 ¼ 7.94, P ¼ 0.047). Similarly results were obtained when 19 female probands were compared to female controls (genotype w2 ¼ 21.28; P ¼ 0.0032, 3 df & allele w2 ¼ 30.88, P ¼ 0.0007, 2 df). All three complementary approaches employed (family-based, case-control and quantitative trait design) suggest a role for the MAO A promoter-region polymorphism. P164 DOES DISABLING FATIGUE IN CHILDREN AND ADOLESCENTS SHARE COMMON GENES WITH DEPRESSION? Fowler T,1 Scourfield J,1 Thapar A,1 and Farmer A2 1 Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK 2 Social, Genetic & Developmental Research Centre, Institute of Psychiatry, London, UK Due to the overlap of symptomology between chronic fatigue syndrome (CFS) and depression it has long been suggested that CFS is simply a form of depression. This view has been given weight by the high comorbidity of the disorder with depression. A screening questionnaire for lifetime ever disabling fatigue was sent to the main carers of twins, aged 8– 17 years, in a population based twin registry. The response rate was 65%. The depression section of the child and adolescent psychiatric assessment (CAPA) was used in a telephone interview with each parent and child. Of those suffering from disabling fatigue 38.8% also fulfilled the ICD10 criteria for depression. Whether this high rate of

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comorbidity is a function of reactive depression to a disabling disorder, overlapping symptomology or due to some shared aetiology is open to question. A multivariate twin analysis was used to look at the questionnaire data on disabling fatigue and responses to the moods and feelings questionnaire. With a Cholesky decomposition by placing fatigue second in the analysis it is possible to test the hypothesis that there are specific genetic and environmental effects that, at least partially, explain the aetiology of disabling fatigue in children and adolescents and that are separate from those that explain depression. This approach allowed us to isolate additive genetic and environmental aetiology specific to disabling fatigue. P165 NO EVIDENCE OF ASSOCIATION BETWEEN DRD4 7 REPEAT ALLELE OR 120 bp DUPLICATION POLYMORPHISMS AND ADHD IN THE IRISH POPULATION Hawi Z, Lowe N, Kirley N, Fitzgerald M, and Gill M Department of Genetics and Psychiatry, Trinity College, Dublin, Ireland Attention Deficit Hyperactivity Disorder (ADHD) is one of the most prevalent childhood onset syndromes affecting 3– 6% of school age children worldwide. Several independent genetic association studies have demonstrated increased frequency of the DRD4-7 repeat allele in ADHD cases compared to controls or excess transmission of the 7 repeat allele from parents to affected offspring. In a previous study [Hawi et al., 2000], we found no significant differences in the frequency of the DRD4 alleles transmitted or not transmitted to ADHD cases from their parents nor when comparing case allele frequencies to ethnically matched controls. In the current study, we conducted Transmission Disequilibrium Test (TDT) analysis on a newly collected Irish ADHD sample (97 trios). We observed no evidence of linkage or association between the DRD4 7-repeat allele and ADHD (w2 ¼ 0.2, P ¼ 0.7). Analysis conducted on both the old and the new samples (175 trios) has also showed no evidence of the reported association between DRD4 and ADHD (w2 ¼ 0.47, P ¼ 0.54). In addition, we also analyzed a 120 bp duplication polymorphism mapped to the control region of the DRD4 gene in the combined sample. Once again, TDT analysis showed no significant differences in the frequency of the transmitted and the non transmitted alleles to ADHD cases (w2 ¼ 0.04, P ¼ 0.92). In conclusion, neither the 7-repeat allele nor the 120 bp duplication polymorphisms seem to confer susceptibility to ADHD at least in the Irish population. P166 A MOLECULAR GENETIC STUDY OF THE VCFS REGION IN EARLY ONSET PSYCHOSIS PATIENTS Ivanov D,1 Kirov G,2 Thapar A,2 O’Donovan M,2 and Owen M2

1

Department of Medical Genetics, Medical University Sofia, Bulgaria 2 Neuropsychiatric Genetics Unit, Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK Velo-Cardio-Facial symdrome (VCFS) is associated with hemizygous interstitial deletions of chromosome 22q11. The VCFS phenotype is complex with multiple congenital abnormalities affecting several tissues and organs. More than 80% of VCFS patients have 22q11 deletions, and more than 90% of the deletions share a 3-Mb region. Some 30% of VCSF patients are reported to have schizophrenia. The rate of VCFS in schizophrenia is 1% compared to the frequency in the general population which is 0.022%. These findings suggest that genes within the deleted region might be involved in the pathogenesis of schizophrenia. We reasoned that schizophrenic patients with an early age at onset might have an even higher rate of VCSF deletions. We screened for 22q11 deletions in 182 juvenile onset psychosis patients who had their age at onset before their 18th birthday (mean age of onset ¼ 15.6 years). We genotyped 3 known microsatellite markers (D22S941, D22S944, D22S264), one CA and one CAG repeat that we designed, and the COMT Val108Met polymorphism (COMT is within the deleted region). We did not find any patient to be homozygous for all of the markers, thus excluding VCSF cases in our population. Several recent studies implicate the COMT Val108Met polymorphism, that determines low or high activity of the enzyme, in playing a role in the pathogenesis of schizophrenia. We screened this marker in the above sample comprising 57 schizophrenia trios, 41 bipolar I trios, 84 schizophrenia cases and 84 unrelated controls. In the case/control study the result was almost significant with the higher activity allele being more common in patients (w2 ¼ 3.40, P ¼ 0.065). The data for the trios was not significant with the higher activity allele being passed 53 times and not passed 47 times (w2 ¼ 0.72, 1 df, P ¼ 0.53). P167 CHILD PROBLEM BEHAVIOUR AND LOWER COGNITIVE ABILITY: A GENERAL POPULATION TWIN STUDY OF THE CAUSES OF ASSOCIATION Jacobs N,1 Rijsdijk F,2 Derom C,3,4 Danckaerts M,5 Hiery E,4,6 Derom R,4 Vlietinck R,3,4 and van Os J1,7 1 Department of Pyschiatry and Neuropsychology, Maastricht University, European Graduate School of Neuroscience, Maastricht, The Netherlands 2 Social, Genetic & Developmental Psychiatry Research Centre, Institute of Psychiatry, London, UK 3 Center for Human Genetics, Catholic University Leuven, Belgium 4 Association for Scientific Research in Multiple Births, Destelbergen, Belgium

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Department of Child Psychiatry, University Hospital Gasthuisberg, Leuven, Belgium 6 Department of Psychiatry and Neuropsychology, University Ghent, Belgium 7 Division of Psychological Medicine, Institute of Psychiatry, London, UK This study examines three possible causes of the association between child problem behaviour and lower cognitive ability: additive genetic factors, common environmental factors and individual-specific environmental factors. 376 twin pairs were examined with the CBCL and the WISC-R. The crosstwin within-variable, within-twin cross-variable and crosstwin cross-variable correlations suggested that genetic and individual-specific environmental factors contributed to the association. Bivariate structural equation model fitting confirmed this, quantifying the genetic correlation between PB and CA at 0.27 (95% CI: 0.12, 0.42) and the individualspecific environmental correlation at 0.17 (95% CI: 0.03, 0.31). Our results indicate that in children three different genetic factors exist that (1) solely influence the liability to PB, (2) only affect CA and 3Influence both PB and CA. While individual-specific environmental factors can influence the liability to both traits, our results suggest that most of the environmental factors that increase the risk of BP do not influence CA and vice versa.

P168 DOPAMINE D2 RECEPTOR GENE POLYMORPHISMS AND L-DOPA INDUCED PSYCHOSIS AND DYSKINESIA IN PARKINSON’S DISEASE Kaiser R,1,3 Hofer A,1 Grapengießer A,1 Gasser T,4 Roots I,1 Kupsch A,2 and Brockmo¨ller J1,3 1 Institute of Clinical Pharmacology, University Clinic Charite´, Humboldt Universita¨t zu Berlin, Germany 2 Department of Neurology, University Clinic Charite´, Humboldt Universita¨t zu Berlin, Germany 3 Department of Clinical Pharmacology, University Clinic Georg-August-Universita¨t Go¨ttingen, Germany 4 Department of Neurology, University Clinic, LudwigMaximilians-Universita¨t, Mu¨nchen, Germany L-Dopa is an effective drug in the treatment of M. Parkinson disease and act through specific binding to the dopamine D2 receptors (DRD2). However, under long-term treatment with L-Dopa severe adverse effects as dyskinesia, psychosis or onoff phenomena may occur and may limit the use of the drug. We investigated, whether polymorphisms of the DRD2 gene family and of the dopamine transporter gene (DAT) may serve as predictors for the development of these adverse effects. A retrospective non interventional study was performed with 188 M. Parkinson patients. We studied nine polymorphisms of the DRD2, two of the DRD3, three of the

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DRD4 and one variable number of tandem repeat (VNTR) of the DAT and sequenced the exons including the promoter region of the DRD2 gene in 55 M. Parkinson patients. There was no significant association between polymorphisms of the DRD2-4 with the appearance of dyskinesia, psychosis or on off phenomena under L-Dopa treatment. However, patients with psychosis were less frequent homozygous for the 10  40 bp VNTR of the DAT compared with patients without psychotic episodes under L-Dopa treatment (41.7% versus 61.4%, P < 0.02). The same trend could be observed for dyskinesia (46.2% versus 64.0%, P < 0.02). Moreover, patients homozygous for the 10  40 bp VNTR of the DAT had a significant lower cumulative probability to develop psychosis or dyskinesia dependent on the number of days treated with L-Dopa (Kaplan-Meier approach, log rank test P ¼ 0.02 for psychosis and P ¼ 0.03 for dyskinesia.

P169 CANDIDATE GENE STUDIES OF ADHD Kent L,1 Bates G,2 Soppitt R,3 Hawi Z,4 Kirley A,4 Lowe N,4 Fitzgerald M,4 Gill M,4 and Craddock N1 1 Molecular Psychiatry Group, Division of Neuroscience, University of Birmingham, UK 2 Birmingham Children’s Hospital NHS Trust, UK 3 Solihull Health Authority, Solihull, UK 4 Departments of Psychiatry and Genetics, Trinity College, Dublin, Eire Attention deficit hyperactivity disorder (ADHD) is a highly heritable, common psychiatric disorder of childhood which probably involves several genes. Molecular genetic studies in ADHD have primarily focussed on candidate genes within the dopamine system, which is thought to be the main site of action of stimulant drugs. However, there are many other plausible candidate gene systems which may be involved in ADHD including other neurotransmitter pathway genes and also genes involved in neurodevelopment. The Birmingham laboratory has focussed on candidates involved in the nicotinic and serotonergic systems and genes of neurodevelopmental relevance. A particularly interesting finding is evidence for the role of the involvement of the serotonin transporter (hSERT) in ADHD. In a collaborative project with Dublin, analysis of haplotypes of 3 polymorphisms across hSERT: an insertion/deletion promoter polymorphism, an intronic VNTR and a 30 UTR SNP, demonstrated significant preferential transmission of haplotypes containing the T allele of the 30 UTR SNP with the long allele of the promoter polymorphism (w2 ¼ 13.18, 3df, P ¼ 0.004) and the 10 repeat of the VNTR (w2 ¼ 8.77, 3df, P ¼ 0.03). Continuing work is now examining the potential role of several neurodevelopmental candidate genes in ADHD e.g. BDNF, NTF3, and NTRK1. The presentation will provide a summary of candidate studies performed to date.

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P170 ASSOCIATION OF THE 480BP DAT1 ALLELE WITH METHYLPHENIDATE RESPONSE IN A SAMPLE OF IRISH CHILDREN WITH ADHD Kirley A,1 Lowe N,1 Hawi Z,1 Mullins C,1 Daly G,1 Waldman I,2 McCarron M,1 O’Donnell D,1 Fitzgerald M,1 and Gill M1 1 Departments of Psychiatry and Genetics, Trinity College Dublin, Ireland 2 Department of Psychology, Emory University, Atlanta, Georgia Several studies have implicated the dopamine transporter gene (DAT1) as conferring susceptibility to ADHD, in particular a VNTR situated at the 30 end of the gene. The 480 bp VNTR allele associated with ADHD has also been reported to be associated with an over-active transporter protein (DAT). Thus children possessing this variant might be particularly responsive to Methylphenidate, a drug known to act by blocking DAT. We have examined this hypothesis and now report an association between the 480 bp VNTR DAT1 polymorphism and methylphenidate response in a sample of 101 Irish children with ADHD. We compared transmissions of the DAT1 VNTR across three categories of parentally rated medication response (‘‘no effect,’’ ‘‘mediocre effect’’ and ‘‘very good effect’’). Transmission of the 480 bp DAT1 allele was significantly greater in children in whom methylphenidate had ‘‘very good effect’’ (w2 ¼ 6.3, 2df, P ¼ 0.042). Using a logistic regression based extension of the TDT we found that transmission of the 480 bp DAT1 variant was significantly associated with children who had a ‘‘very good’’ response versus those who had ‘‘no’’ or ‘‘mediocre response’’ (w2 ¼ 5.49, P ¼ 0.019, OR ¼ 1.51). These findings suggest a role for the high risk 480 bp DAT1 allele in medication response and may help to predict positive clinical outcome in ADHD. P171 CANDIDATE GENE SCREENING IN SUSCEPTIBILITY REGIONS FOR AUTISM Klauck SM,1 Beyer KS,1 Blasi F,2 Bacchelli E,2 Benner A,3 Epp S,1 Poustka F,4 Maestrini E,2 Poustka A,1 and International Molecular Genetic Study of Autism Consortium (IMGSAC)5 1 Deutsches Krebsforschungszentrum, Molecular Genome Analysis, Heidelberg, Germany 2 Department of Biology, University of Bologna, Italy 3 Deutsches Krebsforschungszentrum, Biostatistics, Heidelberg, Germany 4 Department of Child and Adolescent Psychiatry, J. W. Goethe University, Frankfurt, Germany 5 http://www. well. ox. ac.uk/maestrini/iat.html Autism is a severe developmental disorder with an onset in early childhood, characterized by marked social deficits, deviant language and a restricted range of stereotyped repetitive behaviors. A genetic etiology is strongly indicated by

twin and family studies with a risk to siblings of idiopathic cases which is 50–100 times greater than the general population prevalence of 5/10,000 births. The most recent genome screen completed by IMGSAC on a total data set of 152 sibpairs revealed susceptibility loci on 12 chromosomes, with the highest results on chromosomes 2q (MLS 3.74 at D2S2188), 7q (MLS 3.37 at D7S477) and 16p (MLS 2.93 at D16S3102). Using the unique carefully diagnosed sample of more than 140 trios recruited in Germany and Austria, the focus of our investigations is on association studies and positional candidate screening especially in the 7q region under the peak of linkage, but also on chromosome 2q. Coding regions of candidate genes (e.g., WNT2) were systematically screened with SSCP or DHPLC (denaturing high performance liquid chromatography) and sequencing to identify non-synonymous variants. Furthermore, the coding sequences of the methyl-CpG binding protein 2 (MECP2) gene on Xq28 have been systematically screened for mutations or coding variants due to the partial overlap of phenotypical symptoms between autism and Rett syndrome. So far no strong contribution to the genetic etiology of autism of any of the genes under investigation was found in the whole patient sample.

P172 COMPARISON BETWEEN ADHD INDIVIDUALS WITH AND WITHOUT THE 7-REPEAT ALLELE OF DRD4 ON NEUROPSYCHOLOGICAL TESTS Langley K, Marshall L, Lawson DC, Turic D, Owen M, O’Donovan M, and Thapar A. Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK A possible association between the DRD4 7-repeat allele and ADHD has been widely documented, with a recent metaanalysis suggesting an odds ratio of 1.9 for case control studies and 1.4 for family based studies [Faraone et al., 2001]. However, it seems necessary to investigate exactly how the 7 repeat allele may influence the ADHD phenotype. A recent paper by Swanson et al. [2000] investigated whether those with the 7-repeat allele differed from those without, based on neuropsychological tests. Swanson et al. found, contrary to expectations, that the 7-repeat present group did not have greater abnormalities in cognitive functioning. We set out to replicate Swanson’s study and look at a larger variety of neuropsychological tests. We hypothesised that there would be no difference between the 7-repeat present and 7-repeat absent groups, suggesting that the 7-repeat allele is not associated with cognitive abnormalities. Our sample included 133 British Caucasian children aged 6–13 years who fulfilled diagnostic criteria for ADHD. A battery of psychometric tests was administered to each child. The sample was subdivided into those with one or more 7-repeat allele (7-

Abstracts

present) and those without (7-absent). The groups were compared on their performance during such tests using independent t-tests. Demographic and clinical measures were also examined. The 7-present group had higher ADHD symptom scores. No differences were found between the two groups in measures of sustained attention or response inhibition. The 7-present group were found to be significantly more impulsive on the matching familiar figures task (t ¼ 2.148, P ¼ 0.035) and more active, based on the actigraph measures (t ¼ 2.115, P ¼ 0.037). In keeping with the findings of Swanson et al. [2000] these results suggest that those with the 7-repeat allele of DRD4 are not significantly impaired in terms of cognitive deficits. P173 EXAMINING FOR ASSOCIATION BETWEEN HLA-DRB1 AND ATTENTION DEFICIT HYPERACTIVITY DISORDER Payton A,2 Langley K,1 Turic D,1 Lawson DC,1 Ollier W,2 Worthington J,2 Owen MJ,1 O’Donovan MC,1 and Thapar A1 1 Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK 2 ARC Epidemiology Unit, University of Manchester, UK In 1997 Odell et al reported a significant association between HLA-DRB1*04 and ADHD. They also found a nonsignificant increase in the frequency of HLA-DRB1*01. However, the study was a case control study based on 31 subjects and genotyped using PCR RFLP. We attempted to replicate these findings in a much larger well-characterised HLA-DRB1 typed sample using a family-based and casecontrol approach. The sample consisted of 173 children who met DSM-III-R/IV criteria for ADHD or ICD-10 diagnostic criteria for Hyperkinetic Disorder. There was no evidence of significant association of HLA-DRB1*01 or *04 with ADHD using case control or TDT analysis. There was no evidence of preferential transmission of either the DRB1*01 or *04 allele even when further subtypes of these alleles were examined. P174 TEST FOR LINKAGE BETWEEN AUTISM AND TWELVE SINGLE NUCLEOTIDE POLYMORPHISMS IN THE SOMATOSTATIN RECEPTOR 5 GENE Lauritsen MB,1 Nyegaard M,2 Betancur C,3 Colineaux C,3,4 Kruse T,2 Leboyer M,3,5 and Ewald H1,6 1 Department of Psychiatric Demography, Institute for Basic Psychiatric Research, Psychiatric Hospital in Aarhus, Risskov, Denmark 2 Department of Clinical Biochemistry and Genetics, Odense University Hospital, Denmark 3 Inserm U513, Cre´teil, France 4 Department of Child and Adolescent Psychiatry, Hoˆpital Robert Debre´, Paris, France

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Department of Psychiatry, Hoˆpital Albert Chenevier and Henri Mondor, Assistance Publique-Hoˆpitaux de Paris, Cre´teil, France 6 Department of Biological Psychiatry, Institute for Basic Psychiatric Research, Psychiatric Hospital in Aarhus, Risskov, Denmark We searched for linkage disequilibrium between autism and alleles in the somatostatin receptor 5 (SSTR5) gene in 79 trios from Denmark and France. The diagnoses were based on Autism Diagnostic Interview-Revised (ADI-R) and Autism Diagnostic Observational Schedule-Generic (ADOS-G). The SSTR5 gene, which is located at chromosome 16p13.3, is a positional and functional candidate gene for autism. Evidence for linkage to markers in the 16p13 region has been found in two genome-wide scans. Somatostatin is a multifunctional neuropeptide inhibiting growth hormone secretion, and increased growth hormone response to an antimigraine drug have been reported in some individuals with autism. Moreover, the somatostatinergic system interacts with the dopaminergic system; in particular, somatostatin secretion is regulated by dopamine, and the dopamine D2 receptor and SSTR5 interact to form a receptor complex with enhanced functional activity. The transmission disequilibrium test (TDT) was used to compare transmission of each of the two alleles of twelve single nucleotide polymorphisms (SNPs) in the SSTR5 gene and TRANSMIT was used to check for linkage disequilibrium of multilocus haplotypes. The results from this study do not support SSTR5 as a risk gene for autism. P175 ANALYSIS OF THE DERMATOGLYPHIC PROFILE IN THE 22q DELETION SYNDROME Martı´n B,1 Fan˜ana´s L,1 Gutie´rrez B,1 and Bassett AS2 1 Unitat d’Antropologia, Dept. Biologia Animal, Facultat de Biologia, Universitat de Barcelona, Spain 2 Dept. of Psychiatry, University of Toronto and Clinical Genetics Research Program, Centre for Addiction and Mental Health, Toronto, Canada A genetic subtype of schizophrenia has been described in the 22q Deletion Syndrome [Bassett et al., 2001]. Previous studies in schizophrenia have described an excess of dermatoglyphic alterations in these patients [Fan˜ana´s et al., 1996]. Little is known however, about the dermatoglyphic profile of 22qDS subjects and its degree of similarity with the previously described anomalies in schizophrenia. We studied the palmar dermatoglyphic profile of a sample of 22 subjects of Caucasian origin affected by 22qDS and in healthy controls (n ¼ 84) of similar Caucasian origin. We observed higher values for total ATD angle in cases (mean ¼ 90.70, SD ¼ 14.64) than in controls (mean ¼ 84.51, SD ¼ 12.47), being the difference statistically significant (t ¼ 1.99, P ¼ 0.04). In addition, an excess of radial figures in the hypothenar area was found in cases (36.4% 22qDS vs 19%

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controls), specially in the left hand. Interestingly, high fluctuating asymmetry, considering the absolute differences between the right and left a-b ridge count, was observed in the 22qDS subjects, indicating the presence of prenatal instability in this syndrome (mean ¼ 5.59, t ¼ 2.73, P ¼ 0.007). Despite the sample size, the palmprints analyzed suggest the existence of an altered dermatoglyphic profile in 22qDS, involving: i) ATD angle amplitude, ii) presence of radial loops in the hypothenar area and iii) an increment of fluctuating asymmetry. P176 LOCALISATION OF QUANTITATIVE TRAIT LOCI RESPONSIBLE FOR THE HERITABILITY OF LANGUAGE IMPAIRMENT USING DNA POOLING Meaburn EL, Butcher LM, Schalkwyk L, Craig I, and Plomin R SGDP Research Centre, Institute of Psychiatry, King’s College London, UK Language impairment is a common problem of childhood that occurs despite adequate environmental stimulation and in the absence of sensory or neurological deficits. Twin studies have consistently demonstrated a substantial genetic component in its aetiology, which is thought to be due to the combined action of many genes, or quantitative trait loci (QTLs). We hope to identify some of the QTLs that contribute to language disability using a direct association study and DNA pooling. A direct association study design using non-synonymous single nucleotide polymorphism (nsSNP) markers makes it feasible to conduct a genome-wide screen for association between a phenotype and functional variants by hypothesising that the nsSNP markers are functional QTLs. We have capitalised on the wealth of publicly available SNP marker data provided by the human genome project, and using strict selection criteria identified all the nsSNPs with allelic frequencies of at least 10% in Caucasian populations. This approach would be prohibitive in terms of individual genotyping if large samples are used in order to identify QTL associations of small effect size. However, we have employed DNA pooling which significantly reduces this burden. The DNA is pooled from the language-impaired group and a control group, and each pool, rather than each individual, is genotyped and the relative allele frequencies of the two groups are compared. The case pool consists of 397 language-impaired children identified as being in the bottom 15th percentile in a community-based sample on a general language factor that emerged from factor analyses of nine diverse tests of language. The control pool consisted of 1000 individuals randomly selected from children above the 15th percentile. nsSNPs yielding positive results in the casecontrol sample were tested for replication within the control group and using a within-family test based on phenotypically discordant DZ twin pairs.

P177 ANALYSIS OF CANDIDATE GENES IN AutD LINKAGE REGION OF CHROMOSOME 2q Menold MM,1 Raiford KL,1 Shao Y,1 Bost PL,1 Chua ET,1 Wolpert CM,1 Donnelly SL,1 Abramson RK,2 Wright HH,2 Cuccaro ML,1 Gilbert JR,1 and Pericak-Vance MA1 1 Department of Medicine and Center for Human Genetics, Duke University Medical Center, Durham, North Carolina 2 WS Hall Psychiatric Institute, University of South Carolina, Columbia, South Carolina Chromosome 2q32-q33 is a priority region for analysis, potentially containing a susceptibility gene for autistic disorder (AutD). Several genomic screens for AutD have shown linkage to this area of chromosome 2q. Follow-up analyses have strengthened the evidence for linkage by using clinically homogeneous subsets of the data set. In two independent studies, further support for an AutD risk gene in this region was found after seeing an increase in the MLS when stratifying the data sets based on a delay in the acquisition of phrase speech (PSD). Using SNPs, the Collaborative Autism Team (CAT) has looked for an association between AutD and several candidate genes in the linked region of chromosome 2q. Candidate genes included CTLA4 and CD28, both belonging to the Ig superfamily, and located 25–150 kb apart on chromosome 2q33, and DRAK2, a serine/threonine protein kinase that is important in regulating apoptosis. Genotyping, using multiple SNPs in the candidate genes was performed by oligonucleotide ligation assay (OLA) on a data set that included 99 CAT multiplex families and 90 additional multiplex families from the Autism Genetic Resource Exchange (AGRE). Analysis of the data using the Pedigree Disequilibrium Test (PDT) either on the CAT data set, or the AGRE data set, showed no evidence of association at any of the loci (P > 0.4 and P > 0.5, respectively). Haplotype analysis using TRANSMIT also demonstrated no association between the AutD sample sets and any particular haplotype. Even after stratification of the families into a PSD subset, no association was seen for any of the loci. These data indicate that the genes studied here most likely do not contribute to susceptibility in AutD, and that additional candidate genes in this region must be examined. P178 SEROTONIN TRANSPORTER PROMOTER (5-HTTLPR) POLYMORPHISM AND EXTERNALIZING BEHAVIOR IN ADHD CHILDREN: PRELIMINARY RESULTS Cataldo MG,1 Nobile M,1 Marzocchi GM,1,3 Giorda R,2 Baschirotto C,2 Coser S,1 Del Savio M,1 and Molteni M1 1 Child Psychiatry Unit, Scientific Institute ‘Eugenio Medea’, Bosisio Parini, Italy 2 Molecular Biology Unit, Scientific Institute ‘Eugenio Medea’, Bosisio Parini, Italy 3 Cognitive Neurosciece Sector, International School for Advanced Studies, Trieste, Italy

Abstracts

Attention Deficit/hyperactivity disorder is often comorbid with other psychiatric disorders (conduct disorder, depression and anxiety) some of which are related to serotoninergic system functioning. Low serotoninergic activity is associated with aggressive and impulsive behaviors and therefore might be associated with higher scores on impulsiveness in children with ADHD. The relationship between 5-HT and aggression in ADHD children is still unclear [Schultz et al., 2001], with most findings supporting the hypothesis of lower serotoninergic activity in ADHD children with either comorbid Conduct Disorder or aggression [Seeger et al., 2001] and more severe symptoms [Spivak et al., 1999]. This study represents a contribution to this issue. We investigated the possible relationship between the 5-HTTLPR polymorphism and behavioral dimensions as rated by parents on the Child Behavior CheckList 4–18 (CBCL 4–18; Achenbach 1991), the Conners’ Rating Scale [Conners K, 1997] and an Italian adaptation of the Scale for Disruptive Behaviors (SDB— Oosterland et al.) in a sample of 31 children (7 to 13 years old) with ADHD-combined subtype. All subjects were evaluated using the Interview for Children and Adolescent (DICA-R) —DSM IV. There was a significant correlation between the number of short alleles (following a 0, 1, 2, ‘dose effect’) and children’s scores on CBCL—Externalizing Behavior, and SDB—Hyperactivity sub-scale (respectively: P ¼ 0.045; P ¼ 0.045, one-tailed) and a trends with SDB-Oppositional Defiant sub-scale (P ¼ 0.058, one-tailed). These findings support the hypothesis of an association between the serotonin system and impulsive/aggressive behavioral dimensions in ADHD children. P179 SEROTONIN TRANSPORTER PROMOTER (5-HTTLPR) POLYMORPHISM AND EXTERNALIZING BEHAVIOR IN DEPRESSED CHILDREN AND ADOLESCENTS: A PILOT STUDY Nobile M,1 Cataldo MG,1 Giorda R,2 Bellotti B,1 Baschirotto C,2 Marino C,1 Molteni M,1 and Battaglia M3 1 Child Psychiatry Unit, Scientific Institute ‘Eugenio Medea’, Bosisio Parini, Italy 2 Molecular Biology Unit, Scientific Institute ‘Eugenio Medea’, Bosisio Parini, Italy 3 Department of Psychology, University ‘Vita-Salute San Raffaele’ and San Raffaele Scientific Institute, Milan, Italy The conjoint study of the genetic control over serotonergic function and behavioral dimensions, particularly impulsiveness/aggressiveness, can be especially informative when applied to pediatric depression, given the high presence of irritable/impulsive behaviors. In this pilot study we investigated the possible relationship between the 5-HTTLPR polymorphism and behavioral dimensions evaluated by the Child Behavior CheckList 4–18 (CBCL 4–18) [Achenbach, 1991] in a study group of depressed children. Forty children and adolescents with depression/dysthimia (diagnosed

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according to DSM-IV criteria) were genotyped for the serotonin transporter (5-HTT) linked polymorphic region (5HTTLPR). The children’s behavioral patterns were assessed by the Child Behavior CheckList 4–18 (CBCL 4–18). The severity of depressive symptoms was assessed by the Children’s Depression Inventory (CDI) [Kovacs, 1992]. There was a significant correlation (r ¼ 0.35, P ¼ 0.028) between the number of short —S-alleles (following a 0, 1, 2, ‘dose effect’) and children’s scores on CBCL-Externalizing Behavior (encompassing the Delinquent and Aggressive subscales). No other significant correlations between 5HTTLPR genotype and indexes of severity of depression, or CBCL-IB/CBCL-TP scores were found. In conclusion depressed children and adolescents carrying the 5-HTTLPR S-allele could be more exposed to the risk of self-injurious behavior and suicide attempts resulting from greater proneness to experience anger, low self-regulation, impulsiveness. P180 PHENOTYPIC CHARACTERISTICS OF AUTISTIC REGRESSION IN AN INTERNATIONAL MULTIPLEX SAMPLE Parr J,1 Baird G,2 Le Couteur A,3 Rutter M,1 Bailey A,1 and The International Molecular Genetic Study of Autism Consortium (IMGSAC)4 1 Centre for Social, Genetic and Developmental Psychiatry, London, UK 2 Newcomen Centre, Guy’s Hospital, UK 3 Department of Child and Adolescent Psychiatry, University of Newcastle, UK 4 http: //www. well. ox. ac. uk/maestrini/iat. html Some individuals with autism lose skills in the first few years of life, most commonly language, and an environmental aetiology has been suggested. IMGSAC have recruited 486 individuals with a Pervasive Developmental Disorder from 239 multiplex families. Language regression was identified using data from the Autism Diagnostic Interview (ADI), and ADI domain scores, Vineland Adaptive Behaviour Scale domain scores, performance and verbal IQ were compared according to regression status. The incidence of language regression using strict criteria (loss of 5 or more words used with meaning) was 15%, rising to 24% when loss of less complex language was included. Individuals who lost meaningful language acquired first words earlier (21 months) than non-regressors (34 months) (P < 0.001). Concordance for language regression occurred in 15 pairs; 85 pairs were discordant (not significant). Cases who regressed had significantly higher mean ADI domain scores, lower mean Vineland domain scores, and lower mean IQ scores than controls. Some 16% of individuals who lost language had not regained their previous skills and these individuals had significantly lower Vineland domain scores and IQ scores than individuals who lost and then regained language. The incidence of language regression in this multiplex sample is

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broadly in line with the rate in autistic singletons and autistic regression most commonly affected only one individual in an affected pair. The findings suggest that regression is an intrinsic but emergent feature of genetic susceptibility and indexes more severe phenotypic expression.

Department of Human Genetics, Virginia Commonwealth University, Richmond, Virginia 4 Department of Psychology, University of Melbourne, Australia 5 The Murdoch Children’s Research Institute, Royal Children’s Hospital, Melbourne, Australia

P181 COMPLEMENTARY APPROACHES TO THE STUDY OF SUB-TELOMERIC ABNORMALITIES IN A COHORT OF SUBJECTS WITH CO-MORBID PSYCHIATRIC ILLNESS AND MILD LEARNING DISABILITY Pickard BS,1,2 Hollox EJ,3 Malloy MP,1,2 Blackwood DH,2 Porteous DJ,1 Armour JAL,3 and Muir WJ2 1 Dept. of Psychiatry, Royal Edinburgh Hospital, UK 2 Medical Genetics Section, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, UK 3 Institute of Genetics, University of Nottingham, Queen’s Medical Centre, UK

We collected a sample of 104 cases of Turner syndrome (TS) for replication of previously reported findings suggesting imprinted, X-inactivation escaping loci affecting behavior on the X chromosome. For 73 cases where DNA was available, we characterized the X chromosome structure, and monosomic or disomic status using a panel of 12 evenly spaced microsatellite markers. 38 cases were monosomic; 24 were maternal in origin (45, Xm), 7 were paternal in origin (45, Xp) and 7 could not be determined because parental samples were not available. 35 cases were disomic. 8 had p-arm and 2 q-arm deletions on the paternal chromosome, and 10 had parm deletions on the maternal chromosome. 4 p-arm and 1 qarm deletions could not be assigned a parental origin. 10 cases show a complex pattern and are being further characterized. IQ results were in the normal range (Mean 101.16, SD 12.61) and cases did not differ from controls for either verbal or performance measures. In general, cases performed significantly less well on tests of executive functioning compared to controls. Specifically, selective attention and ability to sustain attention was impaired. Cases showed deficits on the contingency naming task (CNT) and controlled oral word association test (COWAT). When compared to the normative sample TS girls preformed significantly less well on accuracy of copy, recall and organisational ability. The pattern of performance exhibited by the (45, Xp) and (45, Xm) were very similar both on measures of IQ and executive functioning. These finding are not in accordance with previous reports, suggesting that (45, Xp) females cannot be distinguished from (45, Xm) females by their performance on these tests.

Recent reports suggest the presence of sub-telomeric chromosomal abnormalities in 2–15% of patients with idiopathic learning disability (US: mental retardation). Psychiatric illness is three times more prevalent in the learning disabled population compared to the general population and may be more heritable. We wish to assess the frequency of subtelomeric chromosomal abnormalities in a cohort of patients with psychiatric illness (principally schizophrenia) co-morbid with mild learning disability. Two approaches are being used; fluorescence in situ hybridisation (FISH) and multiplex amplifiable probe hybridisation (MAPH). FISH with commercially available sub-telomeric probe sets is most suited to detect rearrangements (such as translocations) and large-scale deletions/duplications. MAPH, on the other hand, can accurately detect genomic copy number changes of submicroscopic size. In addition, MAPH is capable of rapid, high-throughput patient screening which is not possible with FISH. The results of the first stage of screening are presented and, where possible, direct comparisons made between these two techniques. The nature of the detected abnormalities may suggest whether the co-morbid diagnosis is caused by contiguous gene deficits (in the same way as velo-cardiofacial syndrome, VCFS) or discrete gene disruptions. Our eventual goal is the isolation and characterisation of the genes responsible for susceptibility to the co-morbid state. P182 MOLECULAR CHARACTERIZATION, IQ AND EXECUTIVE FUNCTIONING IN A SAMPLE OF TURNER SYNDROME CASES FROM AUSTRALIA Riley B,1,2,3 Thiselton DL,1,2 Howard K,4 Dobb R,4 Mill K,4 Ribble R,1,2 Williamson R,5 and Anderson V4 1 Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, Richmond, Virginia 2 Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia

P183 THE COMORBIDITY OF ADHD-RELATED BEHAVIORS AND CONDUCT PROBLEMS IN PRESCHOOL CHILDREN: A TWIN STUDY Ronald A and Plomin R SGDP Research Centre, Institute of Psychiatry, London, UK Conduct and ADHD-related behaviors are common childhood problems, each affecting approximately 5% of children. We present results from a large twin study investigating the aetiology of the relationship between these two traits in preschool children. 2,500 pairs of twins were rated by their parents at ages 2, 3, and 4, using the Revised Rutter Parent Scale for Preschool Children (RRPSPC; Hogg, Rutter, & Richman, 1997), and additionally the Strengths and Difficulties Questionnaire (SDQ; Goodman, 1997) at age 4. The design of the study allowed an aggregate score of these scales

Abstracts

to be calculated across three years, which gave a more reliable estimate of each measure. Behavioral genetic modelfitting techniques partition observed variance of each measure into additive genetic, shared environmental and nonshared environmental influences. Moreover, bivariate models can allow us to ask to what extent shared genetic and environmental factors contribute to the comorbidity between the measures. Twin correlations and univariate model-fitting analyses show that ADHD-related behaviors and conduct problems have different aetiologies. ADHD-related behaviors show strong genetic influence, no shared environmental influence and sibling interaction effects, whereas conduct problems show moderate genetic influence and shared environmental influences. Nonetheless, bivariate analysis yielded a high bivariate heritability, implying that a substantial proportion of the phenotypic correlation is due to shared genetic effects. This is the first large-scale twin study of the relationship between ADHD-related and conduct problems at the preschool age, and suggests that there are common pleiotropic genes influencing these two traits. There are several candidate genes such as the 480-bp allele in a VNTR in the 30 untranslated region of DAT1 and the 7-repeat allele of a 48-bp repeat in exon 3 of DRD4. These results provide support for molecular studies that investigate associations and linkages between candidate genes and both of these phenotypes.

P184 DEPRESSIVE SYMPTOMS IN CHILDREN AND ADOLESCENTS: CHANGING INFLUENCES WITH DEVELOPMENT Scourfield J,1 Rice F,1,2 Thapar A,1 Harold G,2 Martin N,1 and McGuffin P3 1 Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK 2 School of Psychology, Cardiff University, UK 3 SGDP research centre, Institute of Psychiatry, London, UK Parent and self-report questionnaire data were used to examine the genetic and environmental influences on depressive symptoms in a UK sample of 670 twin pairs aged 5–17. Age effects were examined cross-sectionally and longitudinally using data collected over a 3 year period. Results showed that shared environmental effects had significant influence in younger children and acted across time to influence depressive symptoms measured 3 years later. New genetic influences emerged in adolescence but no new shared environmental influences. Sex differences were found, with young girls showing significant genetic effects, but not young boys. In adolescence, depressive symptoms were significantly more heritable in girls, but only from parent-report data. These findings support and extend earlier work which has shown increasing genetic influence on depressive symptoms as children grow into adolescence.

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P185 GENETIC AND ENVIRONMENTAL RISK FACTORS FOR MILD MENTAL RETARDATION Simonoff E,1 Wood N,1 Gringras P,2 Chadwick O,3 Pickles A,4 Maney JA, Higgins S, Karia N and Iqbal H 1 Department of Child and Adolescent Psychiatry, King’s College London, UK 2 Guy’s and St. Thomas NHS Trust, London, UK 3 Department of Psychiatry, Institute of Psychiatry, London, UK 4 School of Epidemiology and Health Sciences, University of Manchester, UK A general population study of 80 12–16 year old children at high risk for mild mental retardation and 114 same-age controls examined medical/genetic and environmental risk factors for mental retardation. Only two previously undetected genetic abnormalities were revealed with cytogenetics and fragile X testing although a much larger number had features on examination, suggestive of an underlying syndrome. A wide range of family adversity was present amongst those with mild mental retardation. P186 AUTISM AND TRANSLOCATION CHROMOSOME Simons A, Croonenberghs J, Van Bever Y, and Deboutte D UCKJA/University of Antwerp, Belgium On the poster we present the case of two brothers with autism, one of them has a balanced translocation (2, 3). The boy with the translocation has a discrepancy in intelligence in favour of the verbal intelligence. His brother is mentally retarded. Although the translocation wasn’t found in the two brothers, they have similar dysmorphic and psychiatric features. In the family on mothers side, several other persons were found to have the same translocation (mainly women). All the other affected family members are well functioning except one girl with mental retardation and epilepsy. There are no other cases of autism in the family. To our knowledge it’s the first time that this translocation is reported in association with autism. P187 ANALYSIS OF GLUTAMATE RELATED GENES IN DYSLEXIA Stephens M, Williams NM, Owen MJ, Williams J, and O’Donovan MC Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK The glutamatergic system, the major excitatory neurotransmitter system in the CNS, is thought to play pivotal roles in the basic molecular mechanisms undelyinging memory and certain aspects of learning. We therefore propose the glutamatergic sytem as a functional candidate gene system for reading disability. We have tested this hypothesis by association analysis of polymorphisms in GRIN1, GRIN2A, GRIN2B, GRIN2C, and GRIN2D (Williams et al. in press),

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as well as novel polymorphisms in genes encoding metabotropic glutamate receptors, AMPA receptors, and the glutamate transporters. Pooled case control analyses suggest an association between two DNA variants in a single NMDA receptor. We are currently seeking replication of this finding by individual genotyping in a family based association sample of 245 complete trios with reading disability. P188 PSYCHIATRIC PROFILE OF CHILDREN WITH VELO-CARDIO-FACIAL SYNDROME-PRELIMINARY FINDINGS Stevens AF,1 Campbell LE,1 Morris R,1 Karmiloff-Smith A,2 Simonoff E,1 Owen MJ,3 Murphy DGM,1 and Murphy KC4 1 Institute of Psychiatry, King’s College London, UK 2 Institute of Child Health, University College London, UK 3 University of Wales College of Medicine, UK 4 Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin, Ireland The genetic disorder, velo-cardio-facial syndrome (VCFS), is associated with variably sized deletions in the q11 region of chromosome 22 and is manifested clinically, in a variety of ways. These may include physical disorders (e.g. congenital heart disease, palatal abnormalities, renal abnormalities and endocrine abnormalities), borderline to mild learning disability, behavioural difficulties and mental health problems (e.g. schizophrenia, mood disorders). This study is concerned with looking at the behavioural difficulties and mental health problems encountered by children with VCFS with the aim of compiling a psychiatric profile and ultimately identifying predictors of subsequent mental health problems in later life. The study recruited 25 children (age 6–16 years) with VCFS and 17 age matched sibling controls. The participants then underwent a battery of psychiatric and behavioural questionnaires (including the Vineland Adaptive Behaviour Questionnaire, The Child and Adolescent Psychiatric Assessment, The Strengths and Difficulties Questionnaire). Preliminary findings indicate that emotional symptoms were found in 53% of the VCFS cohort (10% of controls), conduct problems in 40% (20% controls), attention/hyperactivity problems in 46% (20% controls) and peer problems in 73% (0% controls). These children were part of a larger cohort that are undergoing extensive asessment in order to further delineate possible predictors for mental health problems in later life. P189 PREVALENCE OF IDENTIFIABLE GENETIC CONDITIONS IN TWO CHILD PSYCHIATRIC OUT-PATIENT CLINICS Steyaert J,1 Simons A,2 Tremery S,3 and Fryns J-P1 1 Centre for Human Genetics, University Hospital Leuven, Belgium 2 UCKJA/University of Antwerp, Belgium 3 Stuyvenbergziekenhuis, Antwerp, Belgium

We studied retrospectively the prevalence of identifiable genetic conditions in a group of 682 consecutive new patients, presenting at two out-patient clinics for child psychiatry in the Netherlands in a 5-year period. Together, these two clinics are representative for the second- and thirdline child psychiatric facilities in one region. They cover the whole range of child psychiatric problems. Patients were divided in two groups: (1) neuropsychiatric disorders (ADHD, autism, Tourette...), and (2) other child psychiatric conditions. Based on a number of criteria applied in the two clinics, 55 patients had been referred to the clinical geneticist. Another 51 patients had been seen by a clinical geneticist prior to referral. In 19 (3%) of the subjects an identifiable genetic condition was found (fragile X, minor chromosomal defects...). Seventeen other subjects had non-specific dysmorphic signs. As expected, there are significantly more children with identifiable genetic conditions in the group of subjects with (developmental) neuropsychiatric disorders than in the group with other child psychiatric problems. The prevalence in subjects with ADHD is 5% and 3% in subjects with autism. These findings demonstrate that a significant number of children with child psychiatry disorders may have identifiable genetic conditions. Child psychiatric facilities should be aware of how to screen for these conditions, and how to refer to a clinical geneticist. P190 CHARACTERIZATION OF A THEAORETICALLY-DERIVED PHENOTYPE OF ATTENTION-DEFICIT/HYPERACTIVITY DISORDER Tannock R,1 Martinussen R,1,2 Bedard A-C,1,2 and Ickowicz A3 1 Brain & Behavior Reearch Program, The Hospital for Sick Children, Toronto, Canada 2 Institute of Medical Sciences, University of Toronto, Canada 3 Department of Psychiatry, The Hospital for Sick children, Toronto, Canada One of the major challenges facing current genetic and neurocognitive research in ADHD is the lack of precision in the behavioral phenotype. Notably, recent studies have shown that the behavioral dimensions of inattention and hyperactivity-impulsivity diverge with respect to clinical course, associated impairments, and heritability. Moreover, evidence from twin studies supports the conceptualization of the two behavioral dimensions as separable traits that are continuously distributed in the population. Thus, our approach to addressing the phenotypic heterogeneity was to examine whether individual differences in symptom expression within a dimension are associated with distinct patterns of cognitive functioning, treatment response, and familiality of ADHD. Participants included a clinical sample of 20 school-aged children with ADHD (17 boys, 3 girls, aged

Abstracts

7–11 years old) who were consecutive referrals to a metropolitan pediatric hospital for an evaluation of response to stimulant medication, as well as a small comparison group of 12 healthy, normally developing children (matched for age and gender), who were matched for age and gender with the ADHD group, were recruited from a local community school. Mildly-Inattentive and Severely-Inattentive ADHD subgroups were formed, based upon a median split on the average inattention symptom count, which was created by averaging the total symptom counts obtained from clinical diagnostic interviews conducted with each child’s parent (s) and teacher, and standardized behavior rating scales completed by parents and teachers. Participants performed two brief and simple tasks that required them to remember and reproduce a sequence of spatial locations in either the same or reverse order of presentation. The severely-Inattentive children were characterized by spatial working memory deficits, a positive cognitive response to stimulant medication, and significantly higher rates of ADHD in first-degree relatives compared to Mildly-Inattentive children. These findings provide insight into potential mechanisms underlying individual differences in cognitive functioning and treatment response in ADHD, which in turn may facilitate genetic investigations and more targeted treatments.

P191 EVIDENCE TO SUGGEST BIASED PHENOTYPES IN CHILDREN WITH ATTENTION DEFICIT HYPERACTIVITY DISORDER FROM COMPLETELY ASCERTAINED TRIOS West A,1 Langley K,1 Hamshere ML,1 Kent L,2 Craddock N,2 Owen MJ,1 O’Donovan MC,1 and Thapar A1 1 Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, UK 2 Molecular Psychiatry Group, Division of Neuroscience, University of Birmingham, UK The transmission disequilibrium test (TDT) and other family-based tests are now widely used to test for genetic association due to linkage. Analysis is traditionally based upon analysis of parent-proband trios. Unfortunately it is not always possible to obtain DNA from both parents even in studies of childhood onset disorders and the missing parent is usually the father. Although there are statistical methods available for dealing with this problem, many studies are based on the collection or analysis of complete trios. This selection could lead to systematic bias particularly for psychiatric disorders such as ADHD where the phenotype of the proband or parent might influence family stability and therefore complete parental ascertainment. We examined whether children with ADHD from ‘‘duos’’ (missing paternal DNA) differed from children from complete trios. Children from duos showed significantly higher rates of DSM-IV ADHD-combined type, co-morbid conduct disorder and

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increased conduct disorder symptom scores and a trend for higher total ADHD symptom scores. Excluding duos from sample collection and analysis may result in systematic bias and potentially could lead to further difficulty in replicating effects detected by case control analysis. P192 MOYAMOYA IN COMBINATION WITH ALAGILLE-SYNDROME Tschernigg M University of Graz, Austria We report on a 5 year old male patient with a large chromosomal deletion on chromsome 20 with the following karyotype: 46, XX, del (20) (p11.2-p12.3) leading to a rare phenotypic and genotypic syndrome. He is the fourth child of healthy non-consanguineous parents. Most striking clinical findings are: typical facial dysmorphism, including prominent forehead, deep set eyes, a small pointed chin, a saddle nose, sparse hair, downslanting palpebral fissures and low-set ears. In addition, since the age of three years, the proband showed repeatedly clinical attacks with overcoming exhaustion, permanent headache, unilateral arm and leg weakness and dysphasia. The boy shows psychomotor retardation. MRA demonstrated a high-grade stenosis of both internal carotid arteries. A network of tiny collaterals such as moyamoya changes was demonstrated at the level of lenticulostriatae arteries and the leptomeningeal arteries. A detailed breakpoint characterization by high resolution chromosome banding was performed. It is interesting to mention that the JAG1 gene was deleted in the patient and Alagille syndrome was diagnosed, although some major symptomes were absent. It seems to be a mild form of Alagille-syndrome in combination with an atypically early and heavy form of Moyamoya disease.

P193 A GENETIC IRON METABOLISM DEFECT MAY BE INVOLVED IN THE ETIOLOGY OF ATTENTION-DEFICIT HYPERACTIVITY DISORDER van der Meulen EM,1 Pauls DL,2 Faraone SV,3 Rogers JT,4 van de Giessen EM,1 and Buitelaar JK1 1 Department of Child and Adolescent Psychiatry, University Medical Center Utrecht, The Netherlands 2 Unit of Psychiatric and Neurodevelopmental Genetics, Massachusetts General Hospital, Boston 3 Psychiatry Service, Massachusetts General Hospital and Harvard Department of Psychiatry at the Massachusetts Mental Health Center, Boston 4 Genetics and Aging Unit, Department of PsychiatryNeuroscience, Massachusetts General Hospital, Boston Attention-Deficit Hyperactivity Disorder is highly genetic and is also associated with perinatal risk factors. Since iron is

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essential for brain development, it was hypothesized that prenatal maternal anemia, by causing iron deficiency in the fetal brain, would increase symptom severity. Our sample consisted of 150 carefully phenotyped Dutch children with (DSM-IV based) ADHD. Unexpectedly, anemia appeared to be associated with a decrease in inattention (P ¼ 0.001), impulsivity (P ¼ 0.009) and total symptom severity (P ¼ 0.003). It explained 7.4%, 3.1% and 6.3%, of the respective variances. This may indicate that anemia counterbalances the upregulated dopamine transporters that are found in the striatum of ADHD patients. A genetic defect in brain iron regulation may be involved in the etiology of the disorder.

P194 AN AUTISM PATIENT WITH A T (5; 7) (q14; q31) TRANSLOCATION: LOCALIZATION, IDENTIFICATION AND MUTATION-SCREENING OF CANDIDATE GENES AT THE BREAKPOINTS Vincent JB,1,2 Kolozsvari D,1 Cheung J,1 Haddad M,1 Roberts W,1 and Scherer SW1 1 Dept. of Genetics and Genomic Biology, The Hospital for Sick Children, Toronto, Canada 2 Dept. of Psychiatry, University of Toronto, Canada We have identified a male autism patient with a balanced de novo translocation between chromosomes 5q14 and 7q31. The region on chromosome 7 has been implicated by a number of genome-wide scans, and is believed to harbour at least one susceptibility gene for autism. We have mapped the translocation breakpoints using fluorescence in situ hybridization (FISH), and identified a number of nearby candidate genes, which we have screened for mutations using denaturing high performance liquid chromatography in >96 unrelated autism probands. These genes include KCND2, TSA806 and LSm8 on 7q31.2, just distal to the CFTR locus. RT-PCR analysis for informative SNPs was performed for a number of these genes for this patient, in order to demonstrate monoallelic expression, showing that expression of the derivative copy of these genes may be disrupted in this patient. For KCND2, a gene encoding a brain-specific potassium voltage-gated channel, several amino acid sequence variants were identified in exon 5, including N490D variant present in both affected and one unaffected sibling in one family, and N544S, present in both affected siblings of a second family. Comparative genomic analysis across the translocation breakpoint region on 7q31 has revealed the presence of a large duplicon that is conserved between mouse and humans. This conserved region assisted the identification, by RT-PCR and sequence analysis, of a rare transcript situated close to the breakpoint site. Several EST clusters have also been identified from this region, including one that spans the breakpoint. Further characterisation of these new transcripts is now underway.

P195 PSYCHOSIS IN PRADER WILLI SYNDROME AND CHROMOSOMAL 15 MATERNAL UNIPARENTAL DISOMY Vogels A, Matthijs G, Devriendt K, Legius E, Govers V, Descheemaeker MJ, and Fryns J-P Center for Human Genetics, Leuven, Belgium The Prader-Willi Syndrome (PWS) is a complex and heterogeneous disorder characterised by a variety of clinical features including neonatal hypotonia, hypogonadism, psychomotor retardation, characteristic facial appearance, hyperphagia, childhood onset obesity, behavioral difficulties, skin picking, sleeping abnormalities and a high prevalence (  10%) of psychotic episodes in adolescence and adulthood. Dysfunction of the hypothalamus may be the basis of a number of symptoms in the PWS. PWS results from a loss of paternal expression of genes located on the human chromosome 15q11-13 region. Different molecular mechanisms leading to this loss of expression have been identified including microdeletions, uniparental maternal disomy (UPD) and imprinting center (IC) defects. We investigated the relation between the genetic subtypes of the PWS and psychotic morbidity. Fifty-nine PWS patients had a regular and long term follow-up at the Center for Human Genetics of Leuven. Thirty-eighth patients were aged 13 or older. Six of these 38 patients (15.7%) have psychotic episodes with acute onset and polymorphous symptomatology. The age of onset of the psychotic episodes varied from 13 to 19 years. Five of the six patients with psychotic illness had UPD, the other patient had a sporadic IC defect. None of the psychotic patients had a deletion. None of the patients with a deletion had a psychotic episode in the past, compared with 5 of 7 patients with a UPD and 1 of 2 with a sporadic IC defect. The 3 patients with UPD or IC defect who are not psychotic are still young and at risk for developing a psychotic episode. Our data support the hypothesis (Boer et al., Lancet 2002; 359, 135–6) that overexpression of genes on the maternal chromosome 15 (inside or outside the deletion region) or absence of expression of genes on the paternal chromosome 15 (outside the deletion region) might lead to development of psychotic illness in PWS. P196 MOLECULAR AND CYTOGENETIC STUDIES OF RETT SYNDROME (RTT): A RETROSPECTIVE ANALYSIS OF RUSSIAN COHORT OF RTT PATIENTS Vorsanova SG,1,2 Yurov YB,2 Ulas VY,1 Giovannucci Uzielli M-L,3 Demidova IA,1,2 Gianti L,3 Villard L,4 Iourov IY,2 Beresheva AK,1,2 and Novikov PV1 1 Institute of Pediatrics and Children Surgery, Russian Ministry of Health, Russia 2 National Centre of Mental Health, RAMS, Moscow, Russia 3 University of Florence, Italy 4 INSERM U491, Faculte de Medecine La Timone, Marseille, France

Abstracts

Rett syndrome (RTT) is a severe neurodevelopmental disorder with the incidence of 2.5% in mentally retarded girls in Russia [Vorsanova et al., 1999]. We have performed cytogenetic studies of 60 patients (57 girls and 3 boys) with clinical picture of RTT, selected according to the criteria for diagnosis of RTT developed by B. Hagberg (Hagberg et al., 1996). The spectrum of mutations in the responsible gene, encoding methyl-CpG binding protein (MeCP2) and skewed chromosome X inactivation have been analysed. MeCP2 mutations were found in 76% of RTT girls and one boy. Skewed x inactivation was detected in 21% of RTT girls. Among 60 patients: 57 girls with clinical picture of RTTwere with normal female karyotype (46, XX); one boy was with normal male karyotype in cells of blood (46, XY) and two boys were with mosaic form of Kleinfelter’s syndrome (47, XXY/46, XY) in blood and muscle cells. 24 mothers and parents of RTT girls were with normal karyotype, two mothers—with mosaic forms of Turner syndrome (45, X/46, XX) and one—mosaic karyotype (47, XX, þ mar/48, XXX, þ mar). Specific type of inactive chromosome X (so-called type ‘‘C’’) with unusual staining of chromatin in long arm of the chromosome X was found in 55 (from 57) girls with RTT. This technique was positively used for presymptomatic diagnosis of RTT in five girls in affected families. We believe that the phenomenon of altered chromatin conformation in inactive chromosome X could be used as laboratory test for preclinical diagnosis of the RTT. Supported in part by grants INTAS and Copernicus 2.

P197 WEB-BASED GENETIC EDUCATION FOR AUTISM AND RELATED DISORDERS Wolpert CM,1 Rosen-Sheidley B,2 Donnelly SL,1 Elston L,1 Soper E,1 Turner C,1 Cuccaro ML,1 Folstein S,2 and Pericak-Vance MA1 1 Duke University Medical Center, Durham, North Carolina 2 New England Medical Center, Boston, Massachusetts Previously we reported the results of a pilot survey mailed to families participating in an autism genetic research study. Data indicated that education of the public and health professionals about genetic research findings and their potential clinical application has lagged. ExploringAutism. org, a web site dedicated to helping families with autism stay informed about autism genetics, was developed to provide a credible source of understandable genetic information. Because the population in the pilot study was limited to a small number of families participating in genetics research, we hypothesized that responses would differ in a larger, non-research oriented population. An online version of the survey was included on the web site. Since February 2002, over 7000 people have visited the web site; 412 submitted surveys (a response rate of 6%). Similar to the pilot population, 353 (86%) of respondents have a family member with autism. A majority

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of respondents (90%) indicated that they are not participating in research. When asked about possible causes of autism, 86% cited genetic factors, 31% cited vaccinations and 33% cited other environmental factors (despite lack of medical evidence for the latter). 24% of respondents correctly identified the recurrence risk for autism, but 39% percent grossly overestimated the risk and 31% were unsure. Most respondents favored both genetic testing to confirm a diagnosis of autism (92%) and prenatal diagnosis of autism (75%). 98% indicated an interest in learning more about the genetic basis of autism; 98% felt that this web site was informative. 70% felt that learning about the genetic basis of autism reduced their anxiety. These results suggest the need and desire for education regarding the genetics of autism are not limited to families participating in genetic research. Additionally, the data indicate that web-based tools are an effective method to reach these families.

P198 BLOOD LEAD LEVEL IN CHILDREN WITH BEHAVIORAL AND OR PSYCHIATRIC DISORDERS Zaky E Faculty of Medicine, Ain Shams University, Department of Pediatrics, Cairo, Egypt The current study aimed at assessment of blood lead level in children with behavior and or psychiatric disorders compared to age and sex matched clinically-free children in a trial to delineate a possible role of high blood level and these disorders in such children. On the other hand, hematological status of enrolled children was evaluated as a marker of lead toxicity. Sixty children were enrolled and classified into two groups. Group I included 40 cases suffering from different behavioral and or psychiatric disorders that were recruited randomly from the Child Psychiatry Clinic, Children’s Hospital, Ain Shams University. They were 31 males (77.5%) and 9 females (22.5%) with a mean age of 9.7  3.51 years, while Group II comprised 20 clinically healthy children serving as controls. They were 13 males (65%) and 7 females (35%)with a mean age of 10.6  3.09 years. Full medical history taking, assessment of exposure to lead poisoning risk factors and its symptomatology using a standardized questionnaire, thorough clinical examination, delineation of behavior problems using Arabic Child Behavior Checklist, diagnosis of psychiatric disorders in cases using DSM-IV criteria, scaling of depression and anxiety using Children Depression Inventory and Child Manifest Anxiety Scale respectively for children above the age of 8 years, IQ assessment, CBC, blood smear examination, blood indices calculation, and estimation of blood lead level using the technique of flameless atomic absorption spectro-photometry were done for all children enrolled in the current study. Prevalence of exposure to different risk factors of lead poisoning revealed insignificant differences between cases and controls. ADHD

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was the most commonly encountered psychiatric disorder in the studied sample (35%) followed by conduct and anxiety disorders (22.5%, 20% respectively). Blood lead level was significantly higher in cases compared to controls and showed significant positive correlations with age in years and scores of attention problem, conduct disorder, and socialized aggression scales while it was significantly negatively correlated with patient’s IQ, hemoglobin, and MCH. In coclusion, the current study revealed the importance of screening of blood lead level in patients with psychiatric disorders.

P199 NEUROLOGICAL, BEHAVIORAL, AND PSYCHIATRIC DISORDERS IN AN EGYPTIAN SAMPLE OF PATIENTS WITH PKU AND PSYCHOSOCIAL CHARACTERISTICS OF THEIR CAREGIVERS. IS THERE A VALUE OF AN INTERVENTION EDUCATIONAL PROGRAM FOR CAREGIVERS? Zaky E Faculty of Medicine, Ain Shams University, Department of Pediatrics, Cairo, Egypt The current study was carried out to assess the neurological, behavioral, and psychiatric disorders in a sample of Egyptian patients with PKU and to investigate the psychosocial characteristics of their caregivers. Also, the role of an intervention program (IP) of educational domain for caregivers has been explored. So, a prospective study with an intervention domain was carried out on a sample of Egyptian patients with PKU chosen randomly from patients that attending the Genetics Clinic, Children’s Hospital, Ain Shams University. They were 20 cases; 11 females and 9 males aged from 2.5 to 15 yrs with a mean age of 7.3  3.87 yrs. Only 35% of them were following dietary restriction of phenylalanine (PHE) regularly while 65% followed such restriction intermittently. Household caregivers of studied cases were also enrolled after taking their consent. An IP aiming at education of caregivers about the diseases was implemented with evaluation of its role in improving their disease knowledge. Full history taking, thorough clinical examination, average plasma PHE level measurement, EEG recording, IQ assessment, diagnosis of behavior problems and psychiatric disorders using a Pediatric Problem Check List (PCL) and DSM-IV criteria were performed for all enrolled cases. On the other hand, preliminary interview, assessment of socio-economic (SES), family social function (FSF), and caregivers’ depression, anxiety, and social isolation (DAI) scores were carried out for caregivers. Confirmation of clinically manifest psychiatric disorders was done using DSM-IV criteria. Caregivers’ knowledge about PKU, before and after the implementation of the IP was evaluated using a specially designed disease

knowledge questionnaire (DKQ). All studied cases showed behavioral and/or psychiatric disorders. These included anxiety disorders (70%), ADHD (60%), depression (55%), vegetative disorders (30%), conduct disorders (15%), PDD (10%), and psychotic disorder (5%). Maternal caregivers had significantly higher scores of depression, anxiety, and isolation scales compared to paternal caregivers. The current study showed the importance of a nationwide neonatal screening program for PKU to prevent the devastating sequelae of late diagnosis and treatment and revealed the value of the used IP.

Poster Session 8: Neurological Brain Diseases P200 POLYMORPHISMS IN SLC6A4 (5HTTLPR) AND AACT GENES AS MARKERS OF PROGRESSION FROM MILD COGNITIVE IMPAIRMENT TO ALZHEIMER’S DISEASE Barabash A,1 Cabranes JA,2 Marcos A,3 Gil P,4 Ferna´ndez C,5 Encinas M,6 de Ugarte C,1 and Lo´pez-Ibor JJ2 1 Laboratory of Psychoneuroendocrinology & Genetics, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 2 Department of Psychiatry, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 3 Department of Neurology, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 4 Department of Geriatric, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 5 Department of Epidemiology, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 6 Department of Nuclear Medicine, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain Preliminary data of a prospective study of 42 patients who met criteria for Mild Cognitive Impairment (MCI) are presented. The study was extended up to 1–3 years and a new neuropsychological evaluation was then performed, dividing the patients into two groups: 21 patients who developed Alzheimer’s Disease (AD) and 21 subjects who remained with MCI. Genotyping for AACT and 5HTTLPR polymorphisms were performed. Allele distributions for the two groups were compared using the w2 test and relative risk (RR) and 95% CI were calculated. There were no statistically significant differences in age, sex or time of evolution between both groups. A stratified analysis demonstrated that when the ACT*A allele was present the likelihood to develop dementia carrying also the 5HTTLPR*s allele was 16, 7% while carrying the 5HTTLPR*l allele was 58, 3%. When the ACT*T allele was present the likelihood to develop AD if combined with the 5HTTLPR*s or 5HTTLPR*l allele was in

Abstracts

both cases 53%. The risk to develop AD was 72% lower for individuals carrying combined ACT*A and 5HTTLPR*s alleles (RR ¼ 0.286, 95% CI (0.1–1.0), P ¼ 0.01) than individuals carrying combined ACT*T and 5HTTLPR*s or 5HTTLPR*l allele (RR ¼ 1, 95% CI (0.5–1.8), not significant). When calculated data by genotype, 100% (4/4) of patients homozygous for ACT*A and 5HTTLPR*s did not progress to AD. Interaction analysis for the two genes resulted in a trend to signification (P ¼ 0.06). This significance could be evident when data of patients is included in the study but that have not completed the time of evolution will be collected. These findings suggest that patients with MCI carrying combined ACT*A and 5-HTTLPR*s alleles are less susceptible to develop AD.

P201 STRUCTURE OF INTERRELATIONS BETWEEN PSYCHO-EMOTIONAL INDICES AND SEPARATE METABOLITES CONTENTS IN ELDERLY SUBJECTS Bezrukov VV and Kuznetsov VV Institute of Gerontology, Kiev, Ukraine In aging, the brain metabolic profile and the psychoemotional activity do not undergo changes. To understand the mechanisms of these age peculiarities, we studied the interrelation between separate indices of brain metabolism and personality neuropsychological structure in aging. Eighty-five essentially healthy persons aged 60–74 years; brain MPC by means of Magneton Vision Plus (Siemens), 1.5 t. Analysis of mental working ability (Shult tables, MME and MMPI tests). Correlation analysis of the neuropsychological indices and the content of brain metabolites (NAA, Cr, Cho) in separate areas of the gray and white matter revealed a statistically significant positive correlation between mental working ability and the contents of NAA (k ¼ 0.93), Cr (k ¼ 0.96) and Cho (k ¼ 0.66) in gray matter of occipital area of left hemisphere. The level of mental working ability is negatively correlated with white matter metabolite contents of the left hemispere frontal area: NAA (k ¼ 0.77), Cr (k ¼ 0.53) and Cho (k ¼ 0.65) and only with Cho content of right hemisphere frontal area (k ¼ 0.89). In the elderly, the level of depression correlates negatively with white matter metabolite contents of the frontal area of both left (NAA ¼ 0.97,Cr ¼ 0.89 and Cho ¼ 0.90) and right hemisphere (k ¼ 0.95; 0.83; and 0.71, respectively) and gray matter contents of the left hemisphere occipital area (k ¼ 0.49). In elderly people, the mental working ability indices are predominantly interrelated with the metabolite contents of the frontal and occipital areas of left hemisphere, while the level of depression is correlated with the metabolite contents of the frontal area of both hemispheres.

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P202 POLYMORPHISMS IN THE AACT GENE AND COGNITIVE DECLINE AS A RISK MARKER OF CONVERSION TO ALZHEIMER’S DISEASE IN PATIENTS WITH MILD COGNITIVE IMPAIRMENT Cabranes JA,1 Barabash A,2 Marcos A,3 Gil P,4 Ferna´ndez C,5 Encinas M,6 Domı´nguez M,3 Payno M,3 and Lo´pez-Ibor JJ1 1 Department of Psychiatry, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 2 Laboratory of Psychoneuroendocrinology and Genetics, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 3 Department of Neurology, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 4 Department of Geriatric, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 5 Department of Epidemiology, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain 6 Department of Nuclear Medicine, Hospital Clı´nico San Carlos, Complutense University of Madrid, Spain Preliminary genetic and neuropsychological data of a prospective study of 42 patients who fulfilled criteria for Mild Cognitive Impairment (MCI) are presented. Cognitive assessment was completed by neuropsychological tests (CAMCOG, Rivermead and Wais). Genotyping for a polymorphism Alpha-1-antichymotrypsin gene (AACT) was also performed. After a follow-up period of 1 to 3 years a new neuropsychological evaluation was then performed to make a second diagnosis. The patients were divided into two groups: 21 patients who developed Alzheimer’s Disease (AD) and 21 subjects who remained with MCI. Allele distributions for the two groups were compared using the w2 test and relative risk (RR) and 95% CI was calculated. ROC analysis was performed for neuropsychological data and cut-off values were calculated. There were no statistically significant differences in age, sex or time of evolution between both groups. As a result of ROC curve analysis of CAMCOG scores, sensibility and specificity over 70% to predict AD was obtained in CAMCOG (S ¼ 86%; E ¼ 71%) when cut off values below 79, 5 were chosen. Examination of the allelic frequency of the AACT polymorphism in patients with scores below this cut-off value revealed a significantly enhanced likelihood (91, 79%) to develop AD in those patients carrying the AACT*T allele when compared to those carrying the AACT*A allele (P ¼ 0.01; RR ¼ 1.4, 95% CI ¼ 1.1–2.0) These findings suggest that CAMCOG assessment of cognitive decline in patients with MCI combined with AACT genotyping can be a useful tool for clinicians to predict a progression to AD from MCI so early treatments that may prevent or delay brain deterioration can be considered.

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P203 TAU NEGATIVE FRONTAL LOBE DEMENTIA AT 17Q21: SIGNIFICANT FINEMAPPING OF THE CANDIDATE REGION TO A 4.8 cM INTERVAL Cruts M,1 Rademakers R,1 Dermaut B,1 Sleegers K,2 Rosso SM,3 Van den Broeck M,1 Backhovens H,1 J van Swieten,3 van Duijn CM,1,2 and Van Broeckhoven C1 1 Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology (VIB), University of Antwerp, Belgium 2 Department of Epidemiology & Biostatistics, Erasmus University Rotterdam, The Netherlands 3 Department of Neurology, University Hospital Rotterdam Dijkzigt, The Netherlands We report the results of a genome-wide search in a 4generation pedigree with autosomal dominant early-onset dementia (mean onset age: 64.9 years, range 53–79 years). In this family we previously excluded the known Alzheimer’s disease genes based on linkage analysis and mutation screening of the amyloid precursor protein gene (exons 16 and 17) and the presenilin 1 and 2 genes. In addition we excluded mutations in the prion protein gene and exons 9 to 13 of the microtubule associated protein tau (MAPT) gene. We obtained conclusive linkage with chromosome 17q21 markers with a maximum multi-point LOD score of 5.51 at D17S951 and identified a candidate region of 4.8 cM between D17S1787 and D17S958 containing MAPT. Recent clinical and neuropathological follow-up of the family showed that the phenotype most closely resembled frontotemporal dementia (FTD) characterized by dense ubiquitin-positive neuronal inclusions that were tau negative. Extensive mutation analysis of MAPT identified 38 sequence variations in exons, introns, untranslated regions and the 50 regulatory sequence, however none were comprised within the disease haplotype. Mutations in the recently described novel putative gene Saitohin within intron 9 of MAPT were also excluded. Although our findings do not entirely exclude a mutation in a yet unanalyzed region of MAPT, the apparent absence of MAPT mutations combined with the lack of tau pathology is highly suggestive for another defective gene at 17q21 responsible for FTD in this family. P204 THE ROLE FOR THE TAU PROTEIN GENE IN NEURODEGENERATIVE DISEASES: AN EXTENDED HAPLOTYPE IS ASSOCIATED WITH CORTICOBASAL DEGENERATION Di Maria E,1 Ciotti P,1 Abbruzzese G,1 Donati C,2 Frasson,3 Marchese R,1 Montagna P,2 Munoz D,4 Pramstaller PP,5 Rizzuto N,3 Vigo T,1 Zanusso G,3 Bellone E,1 Ajmar F,1 Tabaton M,1 and Mandich P1 1 Department of Neuroscience, Ophthalmology and Genetics, University of Genova, Italy 2 Institute of Neurology, University of Bologna, Italy

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Department of Neurological Sciences, University of Verona, Italy 4 Department of Pathology and Clinical Neurological Sciences, University of Western Ontario, Canada 5 Dept. of Neurology, Regional General Hospital, Bolzano, Italy Germline mutations of the tau gene were found in familial frontotemporal dementia, and a specific haplotype was demonstrated to be associated with progressive supranuclear palsy (PSP), a sporadic form of tauopathy. We previously demonstrated that the A0 allele of a dinucleotide repeat located in the tau gene as well as a haplotype, spanning the coding region corresponding to the functional domain of the protein, is associated with sporadic corticobasal degeneration (CBD). The present study was aimed at verifying the hypothesis of association of CBD with an extended haplotype across the entire coding region of the tau gene. A series of 18 unrelated patients diagnosed as CBD (2 pathologically confirmed) and 50 controls were genotyped for additional four single nucleotide polymorphisms located in exons 1, 4a, and 8. The linkage disequilibrium analysis identified an extended haplotype composed of 8 polymorphisms significantly overrepresented in CBD patients with respect to controls. The case-control association study confirmed that this haplotype is associated with CBD and might determine the susceptibility to the disease. The linkage disequilibrium analysis of additional markers spanning a larger genomic region across the tau gene is in progress. These results confirmed that the tau gene plays a role in the neurodegeneration process in sporadic tauopathies, and provided further evidences that CBD and PSP share a common genetic background. Granted by Ministero della Sanita’ to PM. P205 BEHAVIORAL AND PSYCHOLOGICAL SIGNS AND SYMPTOMS IN PATIENTS WITH DEMENTIA OF THE ALZHEIMER TYPE (DAT) AND FRONTOTEMPORAL DEMENTIA (FTD): NO EFFECT OF APOE GENOTYPE Engelborghs S,1 Dermaut B,2 Cruts M,2 Van Broeckhoven C,2 and De Deyn PP1 1 Department of Neurology & Memory Clinic, Middelheim General Hospital and Laboratory of Neurochemistry and Behavior, Born-Bunge Foundation, University of Antwerp, Belgium 2 Department of Molecular Genetics, Flanders Interuniversity Institute for Biotechnology, Born-Bunge Foundation, University of Antwerp, Belgium Previous studies investigating the association between ApoE genotype and behavioral and psychological signs and symptoms of dementia (BPSD) in DAT yielded contradictory results. Data on ApoE genotype and BPSD in FTD are lacking so far. We therefore set up a prospective study and included 94 DAT and 10 FTD patients. At inclusion, blood

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sampling for ApoE genotyping was performed as well as a neuropsychological examination and behavioral observation and quantification using behavioral assessment scales (Middelheim Frontality Score, Behave-AD, Cohen-Mansfield Agitation Inventory, Cornell Scale for Depression in Dementia, Geriatric Depression Scale). The ApoE genotypes (w2; P ¼ 0.102) and allele frequencies (w2; P ¼ 0.064) did not differ significantly between DAT and FTD patients, probably due to the small FTD sample. Allele frequencies for DAT and FTD patients were comparable with those reported in other studies: 0.06 vs 0.15 (E2), 0.63 vs 0.75 (E3) and 0.31 vs 0.10 (E4). Comparing behavioral data of DAT patients carrying at least one E4 allele with noncarriers, no significant differences could be revealed (Two Way RM ANOVA). Even when the DAT population was divided into subgroups by ApoE genotype or number of E4 alleles, behavioral data of these subpopulations did not differ significantly. Repeating statistical analysis for the FTD group, no significant differences were found either. In conclusion, we could not reveal any association of ApoE genotype with prevalence or severity of BPSD in DAT and FTD patients. Due to the small sample size, the findings concerning FTD are preliminary till confirmation on an extended study population.

P206 GENOMIC VARIATION IN ALZHEIMER DISEASE Cacabelos R, Lombardi V, and Ferna´ndez-Novoa, L EuroEspes Biotechnology, EuroEspes Biomedical Research Center, Bergondo, La Corun˜a, Spain Alzheimer disease (AD) is a complex disorder associated with multiple genetic defects either mutational or of susceptibility. Environmental factors and/or epigenetic phenomena may also contribute to AD pathology and phenotypic expression of dementia. The potential genes involved in AD include mutational loci (APP, PS1, PS2) and multiple susceptibility loci (APOE, A2M, AACT, LRP1, TNF, IL1, ACE, BACE, BCHE, CST3, MTHFR, GSK3B, NOS) distributed across the human genome. In the present study we have investigated the genomic variation in AD patients (N ¼ 360; age: 74.65  8.62 years; range: 61–96; 239 females and 121 males) as compared with control subjects (CS) with no family history of dementia (N ¼ 113; age: 69.12  11.30 years; range: 53–83; 59 females and 54 males). The genotypes of the APP, APOE, PS1, PS2, A2M, ACE, and cFOS genes were studied. The highest differences between AD and CS were found in APOE, A2M, ACE, and cFOS genotypes. The integration of APOE, PS1, and PS2 genotypes in a trigenic matrix model revealed that approximately 60% of AD patients show a genetic variation with regard to CS higher that 1% and lower than 5%, whereas 30% of the AD population exhibit a genetic variation (GV) higher than 5% with respect to CS. In the bigenic matrix model (APOE þ

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PS1) with a maximum GV of 18 different genotypes CS expressed a range of 7–11 genotypes (x ¼ 9  2) and 15–16 genotypes (x ¼ 15.5  0.5) were found in AD. In the tetragenic matrix model (APOE þ PS1 þ PS2 þ cFOS) with GVmax ¼ 108 (x ¼ 54.4), CS showed a variation range of 14–32 (x ¼ 23  9) and the AD genotypic variation ranged 14–59 (x ¼ 36  22.5). The ratio of expressed genotypes vs repressed genotypes (E/R ratio) was 0.42 in CS and 1.20 in AD. These data clearly indicate that the AD population shows 2–3 times higher genetic variation than CS independently upon the number of genes included in the genomic cluster. The increased GV rate present in AD might constitute a predisposing factor to early neurodegeneration.

P207 ASSOCIATION STUDY OF M129V POLYMORPHISM AT THE PRNP GENE IN ALZHEIMER’S DISEASE Ferna´ndez-Novoa L, Lombardi VRM, Fondevila M, Seoane S, and Cacabelos R Department of Molecular Genetics, EuroEspes Biotechnology, Santa Marta de Babı´o, La Corun˜a, Spain Alzheimer’s disease (AD) and Creutzfeldt-Jakob disease (CJD) are neurodegenerative disorders characterized by a progressive dementia, neuronal loss, and the presence of aggregated protein deposits in the brain. Both types of dementia show sporadic and familial forms. The identification of an interaction between PrP and a member of the APP family indicate the possibility that similar mechanisms may act in the pathogenesis of CJD and AD. About 85% of cases of CJD occurs sporadically or iatrogenically and are not known to be associated with mutations in the PRNP gene. However, it has been reported that Met/Met or Val/Val homozygosity at codon 129 of the PRNP gene predisposes towards sporadic or iatrogenic CJD. Homozygosity at codon 129 is also reported as a prevalent risk factor for the new variant of CJD (nvCJD). In this study, we determined the distribution of the M129V polymorphism in the PRNP gene in AD patients with respect to control non-demented individuals. A total of 129 patients with AD were included in the study (mean age: 69.22  8.45 years; range: 51 to 89 years). Patients were diagnosed according to DSM-IV criteria. One hundred and five control individuals were included (mean age: 66.95  7.76 years; range: 52 to 88) with no family history of dementia or history of psychiatric diseases. Genomic DNA was isolated from lymphocytes and genotypes were determined by PCR and restriction enzyme digestion. The frequency of the M129V polymorphism in AD and controls indicate no statistically significant differences in both samples: M/M genotype: 44.2% vs. 49.5%; M/V genotype: 44.2% vs. 41.9%; V/V genotype: 11.6% vs. 8.6%. Stratifying by APOE e4 genotype, no evidence of an association was observed between the M129V genotypes and APOE e4 carriers in AD. The M129V

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polymorphism of PRNP gene does not seem to be associated with AD in the population studied. P208 ALZHEIMER DISEASE: FALSE POSITIVE ASSOCIATION FINDINGS IN 45 GENES? Finckh U Institute of Human Genetics, University Hospital HamburgEppendorf, University of Hamburg, Germany The genetic association between APOE e4 and Alzheimer disease (AD) was discovered almost one decade ago. A cumulative review of epidemiological, family, twin, linkage, and theoretical studies allows to conclude that there exist risk alleles in several genes in order to fully explain the proportion of AD attributable to genetic factors. However, up to now none of the numerous studies involving more than 100 candidate genes revealed convincing evidence for any risk alleles in genes other than APOE. In the published literature there are more than 45 loci with positive association findings. Most of these findings (including these of our group) could not be confirmed, and there are only few findings deserving further replication studies. This raises the question why and how APOE was found and whether there are strategies to be optimized for future association studies on AD and polymorphic candidate genes. The APOE hypothesis was supported by linkage, existence of intragenic functional polymorphisms, and biochemical data showing an interaction between ApoE and beta amyloid peptide. Besides the chromosome 19 region harboring APOE, genome scans and linkage analyses revealed genomic regions suggestive of linkage with AD on chromosomes 1, 5, 9, 10, 12, 21, and X, in addition to several loci with possible linkage. Furthermore, molecular genetic, biochemical and neurobiological research revealed several molecular mechanisms involved in the pathogenesis of AD. Based on the data now available from the human genome, haplotypes may be identified for any locus, and virtually all genes may be screened for functional polymorphisms. Therefore, future association studies on AD could focus on candidate genes simultaneously fulfilling several criteria that also were essential for discovering APOE. Supported by DFG, grant FI 704/1-3. P209 POSSIBLE ALLELIC ASSOCIATION OF LATE-ONSET ALZHEIMER DISEASE WITH TFAM LOCATED ON CHROMOSOME 10q21 Gu¨nther C,1 Mu¨ller-Thomsen T,2 Alberici A,3 Binetti G,3 Hock C,4 Stoppe G,5 Reiss J,6 and Finckh U1 1 Depts. of Human Genetics 2Psychiatry, University Hospital Hamburg-Eppendorf, Germany 3 IRCCS Centro S. Giovanni di Dio, Brescia, Italy 4 Division of Psychiatry Research, University of Zu¨rich, Switzerland 5 Depts. of Psychiatry 6 Human Genetics, University of Go¨ttingen, Germany

TFAM encodes mitochondrial transcription factor A that participates in mitochondrial genome replication as well as in activation of mitochondrial transcription. Both mechanisms are essential in maintaining mitochondrial function and integrity. Mitochondrial dysfunction may be involved either directly or indirectly in neurodegeneration observed in lateonset Alzheimer disease (LOAD). TFAM locates to chromosome 10q21, a region linked to LOAD[1] and plasma level of Ab42 in LOAD families [Ertekin-Taner et al., 2000: Science 290:2303–2304]. Linkage to 10q21 was most evident in APOE e4 positive samples [Myers et al., 2000: Science 290:2304–2305]. Therefore, TFAM represents both a positional and a functional candidate gene for AD. We genotyped a coding polymorphism in evolutionary non-conserved codon 12 of TFAM (S12T) in 372 patients with sporadic AD and 295 nondemented control subjects. There was a trend towards an association between absence of 12T (T-) and AD (P ¼ 0.062). Conditional logistic regression analysis entering covariates age, gender, TFAM (T vs. T þ ), APOE (e4 þ vs. e4), and interaction [APOEgenderTFAM] revealed an interaction between the three covariates with an exp B (‘OR’) of 3.39 (95% CI 1.93–5.94) in addition to significant associations remaining for APOE (OR 1.96, 95% CI 1.34–2.85) and TFAM (OR 0.74, 95% CI 0.59–0.92). These data suggest a possible association between absence of TFAM allelic variant 12Tand AD which is influenced by gender and APOE genotype. Supported by DFG, grant FI 704/1–3.

P210 IS THE VITAMIN A/RETINOIC ACID-INACTIVATING ENZYME (CYP26A1) THE LATE ONSET ALZHEIMER DISEASE GENE AT CHROMOSOME 10q23? Goodman AB Department of Psychiatry at Massachusetts Mental Health Center, Harvard Medical School, Boston, Massachusetts Late onset Alzheimer disease (LOAD) has been strongly linked to 10q23, the locus of insulin-degrading enzyme (IDE), which degrades beta-amyloid. No IDE polymorphisms have been associated with LOAD, suggesting that IDE is in linkage disequilibrium with the causal gene. Also at this locus within 923 kilobases of IDE is CYP26A1. CYP26A1 causes the hydroxylation and degradation of all-trans retinoic acid (RA), the final product of the vitamin A (retinoid) cascade, and thus controls the availability of RA. How could a retinoid cascade gene be involved in LOAD? IDE expression is directly regulated by RA and contains RA receptor (RAR) response elements in its promoter. In the presence of RA the transcription factor RAR binds to specific DNA motifs in the IDE promoter causing transcriptional activation of IDE and the resultant effects on beta-amyloid degradation. A recent epidemiological study shows that the

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rate of LOAD is lower among Africans in Ibadan than among a comparison sample of African-Americans in Indianapolis. The reason for this lowered risk is unknown, but APOE4 is not a risk factor for LOAD in Ibadan. Diet among the Ibadan community consists mainly of red palm oil and yams, which are high in retinoid and retinoid-containing fatty acids. Perhaps under conditions of high retinoid sufficiency, as in the Ibadan diet, APOE4, which clears postprandial retinyl esters more rapidly than APOE2, does not increase vulnerability to LOAD whereas in Western diets, which are not as retinoid-rich, APOE4-mediated rapid clearance of retinyl esters from the liver results in less availability of brain retinoid. This is the first proposal of a causal connection between altered retinoid catabolism and LOAD. This connection suggests novel treatment possibilities in the form of drugs that prevent RA inactivation. Drugs that increase production or prevent degradation of RA could increase IDE levels and lessen amyloid plaque formation or even degrade preexisting amyloid plaques.

P211 A GENOME SCREEN TO IDENTIFY LOCI THAT MODIFY THE AGE-OF-ONSET OF ALZHEIMER’S DISEASE Hamshere ML,1 Hollingworth P,1 Holmans P,2 Wavrant-De Vrieze F,3 Myers A,4 Marshall H,4 Rice F,1 Jones L,1 O’Donovan M,1 Lovestone S,5 Goate A,4 Hardy J,3 Owen MJ,1 and Julie Williams1 1 Department of Psychological Medicine, Cardiff, UK 2 MRC Biostatistics Unit, Cambridge, UK 3 Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, Maryland 4 Department of Psychiatry, Washington University, St. Louis, Missouri 5 Institute of Psychiatry, London, UK Alzheimer’s disease (AD) is a complex genetic disorder where genes contribute to disease risk and may also modify the age at which the disease develops. We have analysed a powerful sample of sibling pairs affected with late-onset AD, to test for linkage to quantitative trait loci for age-of-onset (AOO). A sample of 451 affected sibling pairs was genotyped using 328 microsatellite markers throughout the genome. Families were ascertained in the UK (Cardiff & Institute of Psychiatry) and the US (NIMH & NIA). Loci contributing to the AOO of disease development were sought using variance component linkage methodologies with the software SOLAR. Covariates included in the analysis include APOE and gender, both known to have differing effects on the risk of AD. Four chromosomes showed regions with a multipoint LOD score greater than 1.0. The region of greatest interest is on chromosome 1.

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P212 REGULATION OF ALTERNATIVE SPLICING OF HUMAN TAU EXON 10 BY PHOSPHORYLATION OF SPLICING FACTORS Hartmann AM,1,2 Rujescu D,1 Andreadis A,3 and Stamm S2 1 Molecular Neurobiology, Department of Psychiatry, Ludwig-Maximilians-University, Munich, Germany 2 MaxPlanckInstituteofNeurobiology,Martinsried,Germany 3 Shriver Center for Mental Retardation, Waltham, Massachusetts Tau is a microtubule-associated protein whose transcript undergoes regulated splicing in the mammalian nervous system. Exon 10 of the gene is an alternatively spliced cassette that is adult-specific and encodes a microtubulebinding domain. Mutations increasing the inclusion of exon 10 result in the production of tau protein which predominantly contains four microtubule-binding repeats and were shown to cause frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). Here we show that exon 10 usage is regulated by CDC2-like kinases CLK1, 2, 3, and 4 that phosphorylate serine-arginine-rich proteins, which in turn regulate pre-mRNA splicing. Cotransfection experiments suggest that CLKs achieve this effect by releasing specific proteins from nuclear storage sites. Our results show that changing pre-mRNA-processing pathways through phosphorylation could be a new therapeutic concept for tauopathies. P213 NATIONAL-ETHNIC TYPES OF AGING Kuznetsova SM and Kuznetsov VV The Ukrainian Geriatric Rehabilitation Center, Institute of Gerontology, Kiev, Ukraine The purpose of this study was to identify national-ethnic types of aging. Cross-sectional and longitudinal (sociohygienic and medico-biological) studies involving 8000 people aged 40–89 years and 300 centenarians of the Caucasus (Abkhasia and Azerbaijan), Ukraine (Crimea, Transcarpathia) and Russia (Central region) were performed. Included were EEG, vessels ultrasound dopplerography, biological age assessment, and psychological tests. We have established the following: (1) Regional peculiarities of age changes of the nervous and cardiovascular systems, namely the delayed rate of these changes in the native population of Abkhasia and Azerbaijan; (2) National-ethnic syndromes of aging: the neurogenic type in Azerbaijanians, the vascular type in Abkhasians and the mixed type in Ukrainians; (3) Varying structure of correlations between the brain functional activity and the level of neurohumoral and hormonal regulation in subjects of the Caucasian region and Russia. The peculiarities of the correlations found in Abkhasians and Azerbaijanians determine the wide range of nervous system ‘reliability’; (4) Psychological portrait specificities in old and long-living individuals of the Caucasian region (high excitability of setting and its low stability, juvenile type of

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emotional manifestations, internal control, etc.) provide for high resistance to stress factors; (5) Some morpho-functional peculiarities of the chromosomal apparatus organization (by heterochromatin) in subjects of the Caucasian region indicate the high constitutional activity of regulatory mechanisms. P214 PLASMA LEVELS OF GLUTAMATE IN EPILEPTIC PATIENTS, TREATED WITH DIFFERENT ANTIEPILEPTIC DRUGS Minkova G1 and Ivanova M2 1 Department of Clinical Laboratory, Medical University, Plovdiv, Bulgaria 2 Department of Molecular Pathology, Medical University, Sofia, Bulgaria Plasma and cerebro-spinal fluid glutamate levels have been reported to be different in patients with neurological diseases, which is hypothesized to play a role in the pathobiology of neuro- and psychiatric disorders. There is high correlation between cerebro-spinal fluid and plasma glutamate levels, and serum concentrations of antiepileptic drugs in drug treated epileptic patients. The cerebrospinal fluid glutamate is higher in patients with new-diagnosticed epilepsy. Plasma glutamate levels were measured in 32 epileptic patients, treated with carbamazepine, valproic acid, lamotrigine or their combination, as follows: monotherapy with valproate (n ¼ 16); monotherapy with carbamazepine (n ¼ 5); monotherapy with lamotrigine (n ¼ 3); polytherapy—carbamazepine and valproic acid (n ¼ 8). HPLC method was used for determination of glutamate plasma levels, and GC methods were used for determination of the drug serum levels. Plasma glutamate levels were from 2.0 mg/l to 46.7 mg/l, mean 22.7  2.0 mg/l. The patients, treated with lamictal had lowest plasma glutamate levels (15.6  4.6 mg/l), highest levels were in the group, treated with carbamazepine (26.5  3.5 mg/l). Patients, treated with valproic acid, had mean values of plasma glutamate 22.2  2.5 mg/l. Increased plasma levels of glutamate in patients with epilepsy and the measuring of these levels during antiepileptic drug treatment might be helpful information about the efficacy of the therapeutic effect of the treatment. P215 THE EFFECT OF PREMUTATION CGG TRINUCLEOTIDE REPEAT EXPANSION, AND EXPRESSION OF FMR-1 PROTEIN, ON BRAIN ANATOMY Moore CJ,1 Daly EM,1 Tassone F,2 Tysoe C,3 Schmitz N,1 Ng V,1 Chitnis X,1 McGuire P,1 Suckling J,4 Davies KE,5 Hagerman RJ,2 Hagerman PJ,2 Murphy KC,1 and Murphy DGM1 1 Institute of Psychiatry London, UK 2 University of California, Davis, California 3 University Hospital of Wales, Cardiff, UK 4 University of Cambridge, UK 5 University of Oxford, UK

Fragile X syndrome (FraX) is associated with an expansion of CGG trinucleotide repeats. People with the full mutation of FraX have >200 CGG repeats, and learning disabilities thought to be caused by methylation of the Fragile X Mental Retardation gene (FMR-1) and subsequent loss of FMR-1 protein (FMRP) production. Premutation carriers of FraX have 50–200 CGG repeats and an unmethylated FMR-1 gene. It was previously assumed that Tr expansion of < 200 has no biological effect. However, there have been recent reports of reduced expression of FMRP in premutation carriers of FraX. Further, we have reported that female carriers of FraX have structural abnormalities in brain anatomy (compared to control subjects) that include reduced volume of the cerebellum, amygdala-hippocampal complex and thalamus. However these findings may be confounded by lyonisation. Thus, in this study, we related CGG Tr expansion and % FMRP expression to brain anatomy in 20 normal IQ male premutation carriers of FraX, and 20 matched controls, using volumetric MRI. We found that premutation carriers had significant differences in brain anatomy from controls. Also grey matter volume in the cerebellum, amygdalahippocampal complex and thalamus was significantly (P < 0.01) reduced as (i) CGG repeat size expanded (ii) % FMRP expression lessened. Thus premutation expansion of X chromosome trinucleotide repeats significantly affect brain, and the current genetic explanation for FraX may require modification. These data provide the first evidence that there is a graded relationship between premutation CGG repeat expansion, % FMRP expression and neuroanatomy in male premutation carriers of FraX.

P216 GENOTYPE AND THERAPEUTIC RESPONSE IN ALZHEIMER’S DISEASE Selezneva N,1 Korovaitseva G,2 Jarikov G,1 Kolykhalov I,1 Kalyn J,1 Rogaev E,2 and Gavrilova S1 1 Alzheimer’s Disease and Related Disorders Research Department 2 Molecular Genetic Dept., Mental Health Research Centre, Russian Academy of Medical Sciences, Moscow, Russia The purpose of this study was to examine correlations between different ApoE genotypes and different types of therapy (cholinergic, glutamatergic and neuroprotective) in randomised groups of AD patients. The 1st group (120 patients) was treated with AchE revearsible inhibitor Amiridin (mean 60 mg daily) during 2 months. The 2nd group (106) patients received a modulator of glutamatergic system Akatinol Memantine (20 mg daily) during 2 months. The 3rd group (96 patients) was treated with the neuroprotective agent Cerebrolysin 20–30 ml i. v. in 150 ml physiological saline (20 injections for one course). Groups of patients were randomised by clinical characteristics including dementia severity, clinical type of AD and frequency of

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cerebral-vascular pathology. In the groups of patients the frequency of e4 allele (s) did not differ statistically. To establish the ApoE alleles, the polymerase chain reaction (PCR) with specific primers was carried out. The amplified product was digested with HhaI. The resulting DNA fragments were electrophoretically separated in a polyacrylamide gel. Responders and non-responders were identified depending on the therapeutic effects. Patients with an improvement by 3 items on the MMSE scale and therapy efficacy on CGI scale as moderate and marked were estimated as responders. The other patients were qualified as nonresponders. The data obtained suggest that the number of non-responders correlates statistically significantly with the ApoE4 genotype only in the group of patients treated with Amiridin. No significant association of the ApoE4 genotype and therapeutic effect was found in the groups treated with Akatinol Memantine and Cerebrolysin.

P217 TOURETTE’ S DISORDER AND DOPAMINE TRANSPORTER GENE POLYMORPHISM Stamenkovic M,1 Stastny J,1 Schuessler P,1 Fuchs K,2 Gebhart C,1 Riederer F,1 Schindler SD,1 Leisch F,3 Hornik K,3 Sieghart W,2 Kasper S,1 and Aschauer HN1 1 University Hospital for Psychiatry, Deparmtent of General Psychiatry Vienna, Austria 2 Department of General Psychiatry and Division of Biochemical Psychiatry Vienna, Austria 3 Department of Statistics and Probability Theory, University of Technology Vienna, Austria Tourette’s Disorder (TD) is a neuropsychiatric disorder with genetic contribution. The etiopathogenesis is still unclear but dopamine systems are hypothetised to play a role. Linkage studies showed evidence for exclusion of major genetic contribution of the dopamine receptor (D1, D2, D3, D4, D5) genes and the dopamine transporter (DAT) gene. The aim of our study was to investigate if alleles and genotypes of DAT are associated with TD. Seventy seven patients (48 male, 29 female) with the diagnosis of TD according to DSM-IV were enrolled in this study. A healthy sex and age matched control group (N ¼ 77) was investigated. Blood samples were drawn from patients and controls. The DAT polymorphism was assessed using polymerase chain reaction (PCR). The 40 bp variable number tandem repeat (VNTR) located in the 30 untranslated region of DAT was amplified. The results showed the presence of 2 DAT alleles in TD patients (allele 5 ¼ 440 bp, 6 ¼ 480 bp). There were no significant differences between TD patients and controls with respect to distribution of alleles 5 and 6 and genotypes of DAT. Our results are comparable with results obtained by Gelernter et al. who investigated genotyping of DAT but in a large pedigree of TD and also could not find linkage of DAT with TD.

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P218 A DISTINCT NEUROCOGNITIVE PHENOTYPE IN FEMALE FRAGILE X PREMUTATION CARRIERS Steyaert J, Borghgraef M, and Fryns J-P Centre for Human Genetics, University Hospital of Leuven, Belgium Fragile X syndrome occurs in 1/2500 to 1/4000 individuals. It is caused by a hypermethylated expansion of more than 200 CGG repeats in the promotor region of the FMR1 gene on Xq27. This so-called fragile X full mutation interrupts expression of the FMR1 gene and is associated with behavioral and neurocognitive signs in males: mental retardation, disturbances in social interactions, hyperexcitability. A least 50% of females who carry the fragile X full mutation have a similar though more attenuated behavioral phenotype. Abnormal expansions of less than 200 CGG repeats at the fragile X-site have a much higher prevalence of approximately 1/400 individuals. This so-called fragile X premutation, was thought not to be associated with any phenotypical sign. Lately, it has been shown that females with the fragile X premutation have a significantly higher risk for premature ovarian failure with consequent infertility. Brain imaging in a small number of subjects has suggested that they may have cerebral anomalies. We administered a battery of sensitive reaction time experiments (De Sonneville Visual Attention Tasks) to 27 adult females with the fragile X premutation and 22 control subjects. We found significant differences in 5/27 females with the premutation, while the other premutation carriers had exactly the same reaction time profile as the control subjects. X-activation ratio was significantly lower in the premutation carriers with the abnormal phenotype. This finding suggest that in a subgroup of female carriers the fragile X premutation is not only associated with reproductive abnormalities, but also with neurocognitive problems.

P219 SYSTEMATIC ANALYSIS OF THE EFFECT OF NOVEL ALZHEIMER DISEASE PS1/2 MUTATIONS ON Aß SECRETION Theuns J,1 Kumar-Singh S,1 Dermaut B,1 Vennekens K,1 Corsmit E,1 Cruts M,1 van Duijn CM,1,2 and Van Broeckhoven C1 1 Department of Molecular Genetics, Flanders Interuniversity Institute of Biotechnology (VIB), University of Antwerp, Belgium 2 Department of Epidemiology and Biostatistics, Erasmus University Medical School, Rotterdam, The Netherlands Mutations in the presenilin genes are an important cause of autosomal dominant Alzheimer’s disease (AD). Both in vitro and in vivo studies showed that AD-related presenilin mutations increase secretion of amyloid b (Ab), specifically that of the longer and more fibrillogenic isoform of 42 amino acids

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Ab42. However when performing mutation analysis of the presenilin (PS) genes in individual AD patients, novel missense mutations can be mistaken as pathogenic mutations rather than rare polymorphisms, in case that no significant segregation data is available as was shown for presenilin 1 (PS1) E318G and presenilin 2 (PS2) P334R. Therefore, it is imperative that novel missense mutations in PS1/2 are analyzed for their effect on Aß secretion using an in vitro assay. Rare polymorphisms such as E318G and P334R do not alter the Aß42/Aß40 ratio. We identified 9 novel missense mutations: 5 in PS1 (A79V, V94M, A231V, L262F, C263P) and 4 in PS2 (G34S, R62H, R71W, T301M) mutations, in multiple series of hospital- or population-based ascertained AD patients. To test whether these mutations were pathogenic we studied their effect on APP processing by ELISA of Aß40 and Aß42 in conditioned medium of stably transfected HEK293 cells on an APPswe background.

P220 POSSIBLE ASSOCIATION BETWEEN THE ESTROGEN RECEPTOR BETA GENE AND AGE-OF-ONSET OF PARKINSON’S DISEASE Westberg L,1 Ha˚kansson A,1 Melke J,1 Johnels B,2 Ahlberg J,2 Eriksson E,1 and Nissbrandt H1 1 Department of Pharmacology 2 Institute of Clinical Neuroscience, Go¨teborg University, Sweden Several studies have shown that women have a lower risk of developing Parkinson’s disease (PD) than men. Postmenopausal estrogen replacement therapy has been associated with a reduced risk of developing PD and with a delayed ageof-onset of PD. Moreover, premenopausal women with PD often experience fluctuations in their symptoms during the menstrual cycle. Estrogen has been reported to stimulate dopaminergic activity, and to assert neuroprotective actions in the nigrostriatal system. Two subtypes of estrogen receptors, alpha and beta, have been reported. Recent studies of estrogen receptor beta knockout mice revealed a degeneration of neuronal cell bodies throughout the brain, particularly evident in the substantia nigra. In order to study the potential contribution of genetic variation in the estrogen receptor beta gene to the development and age-of-onset of PD, we studied a single nucleotide polymorphism in exon 8 (A1730G) in 105 patients with PD and 171 controls. No differences between patients and controls were observed. However, a significant association between the age-of-onset and the A1730G polymorphism was revealed (P ¼ 0.002). When studying men and women separately the effect was more pronounced in women (P ¼ 0.001) than in men (P ¼ 0.2). These data suggest that the A1730G polymorphism in the estrogen receptor beta gene influences the age-of-onset of PD.

Poster Session 9: Anxiety Disorders and Eating Disorders P221 INVESTIGATION OF NMDA RECEPTOR POLYMORPHISMS IN OCD USING QUANTITATIVE AND QUALITATIVE TRAITS Arnold PD, Richter MA, Mundo E, Tharmalingam S, McBride J, and Kennedy JL Centre for Addiction and Mental Health, Toronto, ON, Canada Neuroimaging studies indicate a possible role for glutamate in the pathogenesis of early onset obsessive-compulsive disorder (Rosenberg et al., 2000). We set out to determine if polymorphisms of genes for N-methyl-d-aspartate (NMDA) glutamate receptors were associated with obsessive-compulsive disorder (OCD). We studied three polymorphisms (1001 G/C, 1970 A/G, and 6608 A/G) of the GRIN1 (Glutamate Receptor Ionotropic NMDA Receptor Subunit 1) gene and the 5072 G/T polymorphism of the GRIN2B (Subunit 2B) gene. The minor allele frequency in our sample was 0.06, 0.16, 0.28, and 0.49 respectively. We genotyped 151 nuclear families. Our hypothesis was that NMDAR and GRIN2B polymorphisms were associated with OCD. We used the Family Based Association Test (FBAT) under additive, dominant, and recessive models. Quantitative analysis for association with symptom severity using the YaleBrown Obsessive-Compulsive Scale (YBOCS) was also conducted. The three polymorphisms of NMDAR1 were not associated with OCD or symptom severity. However, the FBAT revealed a significant association of the GRIN2B 5072G/T polymorphism with OCD using the dominant or recessive models (P ¼ 0.009). The analysis of quantitative traits revealed no significant findings, though a trend towards an association with symptom severity (P ¼ 0.053) was seen for the GRIN2B 5072G/T polymorphism using the dominant or recessive models. Although further replication in larger samples is needed, these findings provide preliminary evidence for GRIN2B as a susceptibility locus for OCD, with no evidence for involvement of GRIN1. The GRIN2B genetic results, together with the neuroimaging result of Rosenberg et al. (2000) provide converging support for a role of glutamatergic systems in OCD.

P222 A META-ANALYSIS OF THE ASSOCIATION BETWEEN THE CATECHOLAMINE-O-METHYL-TRANSFERASE GENE AND OBSESSIVE-COMPULSIVE DISORDER Azzam A,1 Mathews C,2 and Reus V1 1 Department of Psychiatry, University of California San Francisco (UCSF) 2 Department of Psychiatry, University of California, San Diego (UCSD)

Abstracts

Obsessive-compulsive disorder (OCD) is a chronic, severely debilitating mental illness that affects approximately 1–2% of the population. Data from twin and family studies have shown that genetic factors contribute to the expression of the disease. The dopaminergic system has been implicated in the pathogenesis of OCD, and catecholamine-O-methyl-transferase (COMT) is a key modulator of dopaminergic and noradrenergic neurotransmission. The gene for COMT has a common polymorphism that has been shown is correlated with a 3–4 fold change in enzymatic activity. Several groups have searched for an association between the COMT gene polymorphism and the presence or absence of OCD. There have been inconsistent results. We conducted a systematic review and meta-analysis of both the published literature and unpublished data. Available data was stratified according to the original study design as either case-control or familybased, and two separate meta-analyses were conducted, using both fixed-effects and random-effects models. These analyses showed insufficient evidence to support an association between the COMT gene polymorphism and OCD. Subgroup stratification based on gender generated no statistically significant associations. These results should be considered in any future work correlating the COMT gene with OCD. P223 SCANNING CHROMOSOMAL REGIONS INCLUDING GENES POSSIBLY INVOLVED IN WEIGHT-GAIN SIDE EFFECT OF ANTIPSYCHOTICS. A PRELIMINARY STUDY Chagnon YC, Me´rette C, Bouchard RH, Emond C, Roy M-A, and Maziade M Laval University Research Center Robert-Giffard, Beauport, QC, Canada Weight-gain and other metabolic disorders are the most serious side effects of certain novel antipsychotics since they are a major cause of non-compliance besides increasing the risk of cardiovascular diseases. We have finished our genome scan (489 markers) for schizophrenia (SZ) and bipolar disease (BP) genes in a sample of 21 large multigenerational pedigrees (480 subjects) with multiple SZ and BP cases. Most SZ patients and some BP patients received antipsychotics and, among them, some became obese whereas others remained at a healthy weight level. Out of 59 patients among six of these pedigrees, 23 were obese (13 SZ and 10 BP). We performed linkage analyses within these six pedigrees in 20 chromosomal regions including candidate genes for obesity and antipsychotic effects (65 markers in total among 15 chromosomes). We used a model-based linkage analysis with a preliminary dichotomic phenotype defined by nurses who reported important weight gain (obese patients) versus no apparent weight gain (patients with acceptable weight). In a recessive model with incomplete penetrance, we observed two linkage signals. On chromosome 8, a LOD of 1.15 near

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the lipoprotein lipase gene was detected, and on chromosome 15 a LOD of 1.7 was located at 5 cM telomeric to a cluster of genes including insulin-like growth factor 1 receptor and insulin-dependent diabetes mellitus 3 loci. A single pedigree (Ped # 230) provided a LOD of 1.57 at 1p31 some 20 cM centromeric to the leptin receptor gene. A simulation study run in 1000 replications of pedigree #230 under linkage provided an expected LOD score of 1.20 (SD ¼ 0.73). These pilot data will be expanded to a whole genome analysis and should help to verify the hypothesis that the weight gain observed in SZ and BP patients using antipsychotics could be genetic in origin, and that such a cohort of SZ and BP patients may help to detect some of the genes involved. P224 THE ROLE OF HT-5 CARRIER GENOTYPE IN DECISION-MAKING IMPAIRMENT OF OCD PATIENTS Cavedini P, Zorzi C, Giordani S, D’Annucci A, Bassi T, *Di Bella San Raffaele Scientific Institute, Department of Neuropsychiatric Sciences, San Raffaele University, Milan Italy. The Gambling Task (GT) detects and measures in the laboratory the decision-making impairment of patients with Obssessive-Compulsive Disorder (OCD) which involves serotoninergic circuits in the ventromedial prefrontal cortex. Consistent data sugges that a good performance at the GT is a valid predictive factor of positive response to standard treatment with selective serotonine reuptake inhibitors (SSRI) (Cavedini, 2002). It has been also demonstrated that the different 5-HT carrier genotypes are significantly correlated with different SSRI treatment outcomes in OCD patients (Di Bella, in press). Analyzing a sample of 80 OCD subjects, we have found a significant difference, in terms of GT performance, between the 5-HT ss 5-HT ll genotype carriers: 5-HT ss carriers show a better decision-making strategy at the task. The study of the correlation between the 5-HT genotype and GT performance can be useful to better understand and improve the predictive value of this two separate factors. Reference: Cavedini et al., 2002, Neuropsychologia, 40 (2): 205–211), Di Bella et al., The Pharmacogenomics Journal, in press. P225 COMT POLYMORPHISM IS ASSOCIATED TO AGGRESSIVE AND HOSTILE BEHAVIOUR IN OCD PATIENTS? Cavallini MC, *Di Bella D, Albertazzi M, Pirovano A, and Bellodi L Fondazione Centro San Raffaele del Monte Tabor, Department of Neuropsychiatric Sciences, Vita-Salute University, Milan, Italy COMT is a key enzyme in the metabolic transformation of catecholamines. Even though controversial, several studies

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suggest an association between a functional polymorphism of COMT gene (Val158Met) and Obsessive Compulsive Disorder (OCD). It has been observed that in schizophrenic patients the allele conditioning the high activity enzyme is associated with aggressive proneness, while heterozygous COMT-deficient male mice exhibited increased aggressive behaviour. Impulsive and aggressive behaviour has been frequently described in OCD patients. Our hypothesis is that OCD patients are more aggressive and hostile than healthy controls, and this phenotype may be associated to the COMT polymorphism. We recruited 85 healthy controls (59 females and 26 males, no differences between sexes for hostility dimensions) and 29 OCD patients (17 females and 12 males, no differences between sexes for hostility dimensions). All subjects fulfilled the Buss Durkee Hostility Inventory Scale (BDHI). Patients showed significantly higher scores than controls for all the investigated dimensions and the total score (T-test ¼ 5.666, d.f. ¼ 112, P < 0.0001). Male and female patients showed higher scores at the BDHI than male and female controls. Preliminary results do not suggest any association between the COMT polymorphism and BDHI scores in patients and controls. Obviously, these results need to be confirmed in a larger sample in order to better understand the possible involvement of COMT in the liability to aggressive behaviour in OCD.

P226 PANIC DISORDER, TREATMENT RESPONSE AND 5-HTT GENE Di Bella D, Perna G, Tentoni G, Bertani A, Cucchi M, Favaron E, and Bellodi L Fondazione Centro San Raffaele del Monte Tabor, Department of Neuropsychiatric Sciences, Vita-Salute University, Milan, Italy Panic Disorder (PD) is a common anxiety disorder. Serotonin Reuptake Inhibitors (SRIs) are the treatment of choice for Panic Disorder (PD). The serotonin transporter (5-HTT) is a prime target for SRIs, thus suggesting that the gene coding for 5-HTT could play a role in the pharmacological response in PD patients. A 44 bp deletion/insertion functional polymorphism within the promoter region of the serotonin transporter gene (5-HTTLPR) leads to different transcriptional rates of 5-HTT protein. We compared the distribution of 5-HTTLPR alleles and genotypes in 47 PD (20 M, 27 F) patients, diagnosed according to DSM-IV criteria, with respect to the clinical response (reduction ¼ >50% in the total scores of the Panic Associated Symptoms Scale) to a standardised treatment with SRIs. We found an excess of the L allele of 5-HTTLPR in the non responder group (w2 ¼ 3.93, 1 d.f., P < 0.047). Although this finding could be simply due to stratification or chance, and needs to be replicated in larger sample, the 5-HTTLPR may influence the treatment response in PD as in other psychiatric disorders.

P227 SSRIs ANTIOBSESSIONAL ACTIVITY IS INFLUENCED BY G-BETA3 VARIANT? *Di Bella D, Erzegovesi S, Henin M, Colombo A, Cavallini MC, and Bellodi L Fondazione Centro San Raffaele del Monte Tabor, Department of Neuropsychiatric Sciences, Vita-Salute University, Milan, Italy Selective Serotonin Reuptake Inhibitors (SSRIs) are the treatment of choice for Obsessive-Compulsive Disorder (OCD). The serotonin transporter (5-HTT) is a prime target for SSRIs, and we recently showed an influence of 5HTTLPR genotypes on the antiobsessional efficacy of fluvoxamine. G proteins are essential regulatory components in the transmembrane coupling system of many receptors involved in SSRI activity. Mutations in G-Protein subunits could result in alteration in second messenger pathways. Recently a functional polymorphism (C825T), which produce a shortened, more active splice variant of the b3-subunit, was associated with antidepressant response in depressive patients. We compared the distribution of C825T in 73 OCD (37 M, 36 F) patients, diagnosed according to DSM-IV criteria with respect to the clinical response to a standardized treatment with fluvoxamine: no association was observed between the response and C825T in the total group. Subdividing the sample according to the presence of a tic codiagnosis, we found that in the group of patients without a tic-codiagnosis (N ¼ 65), those carrying the TT genotype show a better response (F (2, 62) ¼ 4.17, P < 0.0199). Albeit this finding could be simply due to stratification or chance, and needs to be replicated, it supports the hypothesis that the b3-subunit of the G protein may influence the treatment response in a specific subgroup of OCD patients. P228 5-HT2A GENE PROMOTER POLYMORPHISM AS A MODIFYING RATHER THAN A VULNERABILITY FACTOR IN ANOREXIA NERVOSA Kipman A,1,2 Boni C,2 Hanoun N,2 Ade`s J,1 Hamon M,2 Mouren-Sime´oni MC,3 and *Gorwood P1 1 Hoˆpital Louis Mourier (AP-HP, Paris VII) Service de Psychiatrie, Colombes, France 2 INSERM U 288, CHU Pitie´-Salpeˆtrie`re, Paris, France 3 Hoˆpital Robert Debre´ (AP-HP) Service de Psychopathologie de l’Enfant et de l’Adolescent Paris, France The A allele of the 5-HT2A gene (-1438A/G polymorphism) has been associated with anorexia nervosa in four studies, but not in three others. One possibility to explain such a discrepancy is that the A allele acts as a modifying rather than a vulnerability allele. To test this hypothesis, we increased our initial sample of 102 trios (Gorwood et al., Mol Psyhiatry 7:90–94, 2002) with 43 new patients with anorexia nervosa and 98 healthy controls. In addition to confirming the absence

Abstracts

of association on the global sample of 145 patients, we found that patients with the A allele had a significantly later age at onset of the disease (P ¼ 0.032). Furthermore, the A allele also appeared to be transmitted with an older age at onset (P ¼ 0.023) using a quantitative-trait TDT approach. The A allele may thus act as a modifying factor, potentially explaining variations of allele frequency across samples, in which differences in average age at onset are not only possible, but also expected. P229 FEAR CONDITIONING AND SELF-REPORT FEAR RATINGS: GENETIC AND ENVIRONMENTAL SOURCES OF COVARIATION Hettema JM,1 Annas P,3 Neale MC,1,2 Fredrikson M,3 and Kendler KS1,2 Departments of 1Psychiatry and 2Human Genetics, Medical College of Virginia Campus of Virginia Commonwealth University, Richmond 3 Department of Psychology, Uppsala University, Sweden We present data from a study of fear conditioning in a sample of 90 MZ and 83 DZ adult same-sex twin pairs. Prior analyses in this sample have established that experimentally derived electrophysiologic measures of fear conditioning are moderately heritable. In this study, we examined the genetic and environmental sources of covariation between these experimentally derived measures of fear conditioning and selfreport ratings of 16 items reflecting specific, social, and agoraphobic fears. Factor-derived scores for the electrophysiologic and self-report measures were analyzed using bivariate structural equation modeling. Both the electrophysiologic and the self-report fear factors possess heritabilities of about 55%, with the remainder of the variance explained by individual specific environment. Best-fit models estimate a genetic correlation between the physiologic and self-report fear measures of about 50%, suggesting that the trait of fear conditioning may represent a valid endophenotype for genetic studies of fears and phobic disorders. P230 CCK NEUROTRANSMITTER SYSTEM GENE POLYMORPHISMS–ASSOCIATION ANALYSIS IN TWO INDEPENDENT GERMAN PANIC DISORDER SAMPLES Ho¨singV,1 Kuhlenba¨umerG,1 SchirmacherA,1 GarritsenHS,1 No¨then MM,2,5 Franke P,2 Rietschel M,2 Maier W,2 Sand P,3 Jacob,3 Fritze J,4 Beckmann H,3 Sibrowski W,1 Ringelstein EB,1 Arolt V,1 Sto¨gbauer F,1 and Deckert J1 1 University of Mu¨nster, Germany 2 University of Bonn, Germany 3 University of Wu¨rzburg, Germany 4University of Frankfurt, Germany 5 University of Antwerp, Belgium CCK induces panic attacks in patients with panic disorder. Reports on associations of CCK neurotransmitter system

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gene polymorphisms with panic disorder have been inconsistent. In the present study, we therefore analyzed genetic variation of CCK and the CCK B receptor gene polymorphisms in panic disorder. We determined allele and genotype frequencies first in a German DSM-IIIR sample (n ¼ 92) and subsequently in a second German DSM-IV sample (n ¼ 66) in comparison with gender- and age-matched control samples using RFLP (BSL I and Hin6 I) and fragment analysis. Association analysis in the German DSM-IIIR sample showed a significant excess of the 188G CCK allele in panic disorder (P ¼ 0.03). While in the smaller DSM-IV sample this excess was not significant (P ¼ 0.32), in the combined sample again a significant association (P ¼ 0.02) was seen. Our results are in contrast with those reported by Hattori et al. (Mol Psychiatry 6:465–470, 2001). They add to association findings in the CCK gene by individual groups each of which has not been replicated up to now. One possible explanation obviously is population-specific linkage disequilibrium with another, clinically relevant polymorphism, another population-specific effects of individual polymorphisms. Further studies at the genetic and functional level are necessary to probe the latter possibility. P231 OCD SPECTRUM AND RHEUMATIC FEVER: RESULTS FROM A FAMILY STUDY Hounie A,1 Pauls D,2 and Miguel E1 1 Department of Psychiatry, University Sa˜o Paulo, Brazil 2 Psychiatric and Neurodevelopmental Genetics Unit Harvard Medical School OCD occurs in patients with rheumatic fever (RF) with or without Sydenham chorea (SC) suggesting a possible common neurobiological substrate. To date, there are no family studies verifying the rate of OCD in first-degree relatives of RF patients. The objective of this study was to verify the frequency of OCD in first-degree relatives (FDR) of RF patients with and without chorea compared to a control group. We aimed to determine if there is a familial relationship between OCD and other putative spectrum disorders such as body dysmorphic disorder (BDD) and tic disorders (chronic tic disorder and Tourette) and RF. The FDR of the first 57 consecutive RF patients from a pediatric clinic were interviewed. All RF patients were interviewed directly and the FDR (n ¼ 232) were interviewed directly in 88% of the cases. Of these families, 26 had and 31 did not have SC. Twenty-nine control families from the orthopedics clinic were collected and the FDR (n ¼ 100) were directly interviewed in 95% of the cases. All subjects were studied with structured interviews (SCID, K-SADS). Best estimate diagnoses were assigned. The rate of OCD (3.4%; n ¼ 8) among FDR was not statistically different from the control group (2%) (P ¼ 0.47). The morbid risks of any relative in these samples having OCD were 4.12% (RF group) and 3.82% (control group). The rates of BDD were 3.6% [n ¼

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6/167] vs. 0.% [n ¼ 0/66]; P ¼ 0.11 and the rates of tic disorders were 3.9% [n ¼ 9/232] in the RF group vs. 2%[n ¼ 2/100] in controls; P ¼ 0.38). The morbid risks for tic disorders were 3.86% and 2.1% in RF and controls, respectively. The combined rates of OCD, BDD and tic disorders in adults tended to be higher than controls (P ¼ 0.04). The most established OCD related disorders (BDD and tic disorders) when combined to OCD tended to be higher in FDR of RF. If confirmed, and considering BDD and tic disorders as part of the OCD phenotype, our data may suggest a possible familial relationship between some OCD spectrum disorders and rheumatic fever.

P232 GENDER IN OBSESSIVE-COMPULSIVE DISORDER: CLINICAL AND GENETIC FINDINGS Lochner C,1 Hemmings SMJ,2 Kinnear CJ,2 Moolman-Smook JC,2 Corfield VA,2 Niehaus DJH,1 and Stein DJ1 1 MRC Unit on Stress and Anxiety Disorders, Department of Psychiatry, University of Stellenbosch, South Africa 2 MRC/US Centre for Molecular and Cellular Biology, University of Stellenbosch, South Africa. There is increasing recognition that obsessive-compulsive disorder (OCD) is not a homogenous entity. It has been suggested that gender may contribute to the clinical and biological heterogeneity of OCD. Two hundred and forty seven (N ¼ 247; 122 male, 125 female) patients with OCD and 746 normal controls underwent structured interviews and were genotyped for monoamine SNPs. Clinical and genetic data were analyzed across gender. Males had an earlier age of onset, while females were more likely to have poor insight. Males were more likely to have comorbid sexual compulsions (past), while females were more likely to have a history of comorbid panic (current & past), specific phobia (current & past), anorexia nervosa (past), bulimia nervosa (past), trichotillomania (current) and self-injury (current). Childhood trauma in general was significantly higher in patients with OCD than in healthy controls (P < .001). Female patients reported significantly more sexual abuse than males (P < .03), whereas male patients reported significantly more emotional negligence than females (P 2 for the Val allele. A significant association was also noted with allele 2 of the T102C polymorphism in the 5HT2A receptor in Caucasian case-control samples, but not in Asian samples. Significant evidence of publication bias was not encountered. The results of ongoing analyses of the 48-base-pair repeat polymorphism in exon 3 of DRD4 and of the (CAG)n polymorphism of KCNN3 will also be presented. Meta-analysis likely will continue to prove useful in establishing the relationships between particular gene variants and schizophrenia; however, some of the most useful attributes of the procedure (e.g., the ability to detect moderators of effect size) may still suffer from low power until more data become available.

P267 ANTIPSYCHOTIC EFFICIENCY IS PARTLY EXPLAINED BY 5-HT2A (-1438A/G) GENETIC POLYMORPHISM Hamdani N,1 Boni C,2 Hamon M,2 Ade`s J,1 and Gorwood P1 1 Hoˆpital Louis Mourier (AP-HP, Paris VII). Service de Psychiatrie, Colombes. France 2 INSERM U 288, CHU Pitie´-Salpeˆtrie`re, Paris, France There is large individual variation in the type of clinical response to neuroleptics and antipsychotics for schizophrenic subjects. Age at onset, familial history, severity of the disorder and initial tolerance are considered to have low predictive value. Recent progress in pharmacogenetics may help to distinguish which treatment would fit more adequately a specific patient. The gene coding for the 5-HT2A receptor is the most studied, as antipsychotic drugs may have their clinical specificities through higher affinity for this receptor, but the role of this gene is still unclear. Ninety French in- and outpatients (32 women and 58 men) meeting DSM IV criteria for schizophrenia, treated by antipsychotic drugs (amisulpride, olanzapine or risperidone), were assessed with the DIGS (lifetime psychiatric symptoms) and the May and Dencker Scale (quality of response to pharmacotherapy). Patients were genotyped for the 5-HT2A.1438A/G promoter polymorphism using a polymerase chain reaction. Homozygous genotypes for the A allele were more frequent among resistant patients. The difference was statistically significant (w2 ¼ 7.8, P ¼ 0.005, OR ¼ 5.12, IC [1.5516.9]). Analysis of allele frequencies also showed a significant difference between resistant and sensitive patients (w2 ¼ 7.8, P ¼ 0.005, OR ¼ 5.12, IC [1.55-16.9]). As different clinical symptoms may confound the pharmacogenetic effect, we conducted a logistic regression analysis. A significant trend for association between the 5HT2A polymorphism and response for treatment (OR ¼ 1.97, P ¼ 0.02) and, independently, between the illness severity and response for treatment (OR ¼ 1.49, P ¼ 0.0004) were observed.

Abstracts

P268 FAMILY-BASED ASSOCIATION STUDIES OF THE 5-HT5A GENE: EVIDENCE FOR ASSOCIATION AND LINKAGE WITH AGE AT ONSET AND THERAPEUTIC RESPONSE IN SCHIZOPHRENIA Dubertret C,1,3 Hamoun N,3 Ade`s J,1 Hamon M,3 and Gorwood P1,2 1 Hoˆpital Louis Mourier (AP-HP, Paris VII). Service de Psychiatrie, Colombes, France. 2 INSERM U 288, CHU Pitie´-Salpeˆtrie`re, Paris, France The gene which codes for the 5-HT5A receptor can be regarded as a good candidate gene for schizophrenia considering, for example, the neurobiological and pharmacological data which highlight the important interaction between serotonin and dopamine in schizophrenia. We used a progressive strategy with two different approaches (haplotype relative risk and transmission disequilibrium test) to investigate the 12A/T polymorphism of the 5-HT5A gene in 103 patients with DSM-IV diagnoses of schizophrenia, and their 206 parents. We found evidence for association (P ¼ 0.008) (HRR), and for linkage (P ¼ 0.02) (TDT) between the T allele and schizophrenia. Patients with the T allele had a significantly later age at onset (P ¼ 0.003) and good treatment response (P ¼ 0.005). Furthermore, the allele was transmitted with an older age at onset (P ¼ 0.01) and a better treatment response (P ¼ 0.04) according to the QTLTDT approach. We thus found convergent evidence in our sample for a significant role of the 5-HT5A gene in schizophrenia, which may be more specifically involved in patients with a later onset and good treatment response.

P269 FAMILY-BASED ASSOCIATION STUDY OF THE GENE CODING FOR THE 5-HT6 RECEPTOR (C267T) POLYMORPHISM) IN SCHIZOPHRENIA Dubertret C,1,2 Hamoun N,2 Ade`s J,1 Hamon M,2 and Gorwood P1 1 Hoˆpital Louis Mourier (AP-HP, Paris VII). Service de Psychiatrie, Colombes, France 2 INSERM U 288, CHU Pitie´-Salpeˆtrie`re, Paris, France The gene which codes for the serotonin 5-HT6 receptor may play a role in the pathogenesis of schizophrenia according to presnece of the serotonin 5-HT6 receptor in limbic and cortical regions of brain, and the high affinity of atypical antipsychotics for 5-HT6 receptors. We recruited 103 trios (patients with DSM-IV diagnoses of schizophrenia, and both parents), and investigated the C267T polymorphism 5-HT6 receptor gene with two different family-based association study (family-based association study haplotype relative risk and transmission disequilibrium test). We found no excess of transmission of one allele from the parents to their affected children, using the haplotype relative risk (P ¼ 0.60), and showed no evidence for linkage between C267T polymorph-

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ism and schizophrenia, using the transmission disequilibrium test (P ¼ 0.71). Our results do not support a major role of the 5HT6 receptor genes in the etiopathogenesis of schizophrenia.

P270 RHEUMATOID ARTHRITIS AND SCHIZOPHRENIA: AN EXCLUSION OF ASSOCIATION Gorwood P,1 Pouchot J,2 Vinceneux P,2 Pue´chal X,2 Flipo RM,2 De Bandt M,2 Ade`s J,1 and the C. R. I2 1 Hoˆpital Louis Mourier (AP-HP, Paris VII). Service de Psychiatrie, Colombes, France 2 Club Rhumatisme et Inflammation. France There is wide evidence for a decreased risk of rheumatoid arthritis in patients with schizophrenia. Nevertheless, very few studies have looked at the risk of schizophrenia in a group of patients with rheumatoid arthritis. We prospectively investigated, with the SCL-90R, 220 consecutive outpatients with rheumatoid arthritis and 196 consecutive outpatients with various medical conditions, half of them suffering from psoriatic arthritis (a medical condition close to rheumatoid arthritis). The SCL-90R appears to be a valuable tool to distinguish patients with schizophrenia from the outpatients of our sample, the former having more ‘paranoid ideation’ (P ¼ 0.004) and more ‘‘psychoticism’’ (P < 0.001) than the latter. The ‘‘paranoid ideation’’ dimension was significantly lower (25% decrease) in the sample of patients with rheumatoid arthritis compared to the combined control group (P ¼ 0.005), ratings under the median value being more frequent in the former group (P ¼ 0.025). Confounding factors might not explain this difference according to the regression logistic analysis performed. This data represents further evidence for a decreased risk of schizophrenia (assessed in a quantitative way) in a population of subjects with rheumatoid arthritis.

P271 NEW STRATEGIES IN THE GENETICS OF SCHIZOPHRENIA: TOWARD A BETTER PHENOTYPIC CHARACTERIZATION OF PATIENTS WITH NEURODEVELOPMENTAL ABNORMALITIES Gourion D, Goldberger C, Bayle FJ, Olie´ JP and Krebs MO INSERM E0117; Service Hospitalo-Universitaire, Hopital Sainte-Anne, Paris. France Schizophrenia is a complex heritable disease with both genetic factors interacting with the environment. However, the progress in their identification is limited by the crucial issue of the phenotypic characterisation. In the context of the neurodevelopmental hypothesis, Neurological Soft-Signs (NSS) and Minor Physical Anomalies (MPAs) are candidate phenotypes, because they occur frequently in patients with

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schizophrenia, and in non affected biological relatives. However, their intrafamilial transmission remained to be ascertained. We studied the intrafamilial variance of NSS and MPA in order to determine their familiality within trios. In a second step, the non-affected parents of children with schizophrenia were dichotomized between presumed and non-presumed carriers for the genetic vulnerability to schizophrenia. Parents were defined ‘‘presumed carriers’’ if they had a first or second degree family history of schizophrenia in their ascendants and/or collaterals. We observed a significant within families transmission of NSS (Intra Class Coefficient ¼ 0.64; F ¼ 2.6; df ¼ 17, 17; P ¼ 0.02) but not of MPA (ICC ¼ 0.10; F ¼ 0.7; df ¼ 17, 17; ns). In addition, NSS total scores (P ¼ 0.0001), motor coordination (P ¼ 0.001) and integration subscores (P ¼ 0.003) were higher in presumed carriers than in non-presumed carriers. Presumed carriers had also higher MPAs total score as compared to nonpresumed carriers (P ¼ 0.05). These results provide direct support to a high heritability of NSS within families of schizophrenic probands. MPAs are also associated with the genetic risk for schizophrenia, even in the absence of the disease, but could be more sensitive to environmental factors. Both NSS and MPA are easy and rapid to assess and could be used as a quantitative phenotype in extensive genetic studies of schizophrenia.

P272 GENOMIC VS EPIGENOMIC MOUSE MODELS IN SCHIZOPHRENIA RESEARCH Guidotti A, Grayson DR, Noh JS, Tremolizzo L and Costa E Psychiatric Institute, Department of Psychiatry, College of Medicine, UIC, Chicago, Illinois Vulnerability to schizophrenia has been related to genetic factors but the polygenic nature and the non-Mendelian inheritance of this disease suggests that gene expression defects may also be determined epigenetically. A consistent neurochemical abnormality found in brains of schizophrenia patients is a defect in GAD67 and reelin expression in the GABAergic interneurons of the cortex (Guidotti et al. Arch Gen Psych, 57: 1061, 2000). The heterozygous reeler mouse (HRM) (Costa et al. Neurobiol Dis 8: 723, 2001), which includes a dopaminergic deficit in ventral striatum (Ballmaier et al. Eur J Neurosci, 2002), is a model for testing treatments for transmitter and genetic defects in schizophrenia. Although the HRM model is oversimplified and genetically reductionistic, it has proven valid for pharmacological studies. However, the polygenic nature of schizophrenia could depend on epigenetic transcriptional repression due to the hypermethylation of several gene promoters. The onset of CpG island hypermethylation may begin with events that increase DNA methyltransferases (DNMT1, 3A, 3B) in GABAergic interneurons. Here, we

present an epigenetic mouse model based on clinical studies performed about 30 years ago by Antun et al. (1971) and by other investigators. They administered high doses of methionine (MET) for two weeks to schizophrenics. MET, a precursor of S-adenosylmethionine, elicits an exacerbation of schizophrenia symptoms, probably by a hypermethylation of several CpG island-rich promoters. Administering MET to mice, we found cortical GAD67 and reelin downregulation, probably associated with a multigene expression defect. Valproate, a histone deacetylase inhibitor (HDAC) that probably induces DNA demethylase activity, reduces promoter methylation and normalizes brain levels of GAD67 and reelin. Multiple molecular forms of HDAC are expressed in brain and we are now studying how many of these HDACs are expressed in GABAergic interneurons to compare different HDAC inhibitors to valproate.

P273 NO EVIDENCE FOR LINKAGE AND LINKAGE DYSEQUILIBRIUM OF SCHIZOPHRENIA TO NOTCH4 LOCUS IN TAIWANESE FAMILIES Hwu H-G,1 Liu C-M,1 Ou-Yang W-C,2 Jann H-Y,3 Chen J-J,3 Lee SF-C,3 Hong C-J,4 and Fann CS-J5 1 Department of Psychiatry, College of Medicine, National Taiwan University, Taipei, Taiwan 2 Institute of Public Health, National Yang-Ming University; Chia-Nan Psychiatric Center, Deaprtment of Health, Tainan, Taiwan 3 Taoyuan Psychiatric Center, Taoyuan, Taiwan 4 Department of Psychiatry, Veterans General Hospital, Taipei, Taiwan 5 Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan Evidence was reported for a highly significant linkage disequilibrium between schizophrenia and a trinucleotide repeat polymorphism (CTG)n in exon 1 of NOTCH4 gene located at chromosome 6p21 [Wei and Hemmings, 2000]. In order to evaluate linkage disequilibrium of schizophrenia to this locus, we genotyped this polymorphism in 103 Taiwanese schizophrenic families with at least two affected siblings. Linkage disequilibrium was assessed using the Family Based Association Test Program (FBAT). The result didn’t support the association of this polymorphism with schizophrenia as previously reported (chi-square ¼ 3.782, P ¼ 0.436). We also genotyped two flanking microsatellite markers and evaluated linkage of schizophrenia to this chromosome region using GENEHUNTER program. Non-parametric analysis revealed slightly positive NPL scores over this region (NPLZ ¼ 0.91, P ¼ 0.17). Our results didn’t support linkage or linkage disequilibrium evidence of schizophrenia to the NOCTH4 locus in an ethnically distinct Taiwanese sample.

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P274 ASSOCIATION ANALYSIS BETWEEN THE HKCA3 GENE AND JAPANESE SCHIZOPHRENIC PATIENTS, INCLUDING AN EXAMINATION OF GENETIC ANTICIPATION Imamura A,1 Fujimaru K,1 Tsujita T,1 Hashida A,1 Mori T,1 Oda R,1 Matsumoto S,2 Hayashida M,3 Nakane Y,1 and Okazaki Y4 1 Division of Psychiatry, Department of Neurosensory Medicine, Nagasaki University Graduate School of Biomedical Sciences, Japan 2 Michino-o Hospital, Nagasaki, Japan 3 Health Center, Nagasaki University, Japan 4 Department of Neuropsychiatry, Mie University School of Medicine, Tsu, Japan Several researchers have suggested a statistically significant association between larger numbers of CAG repeats in the hKCa3 gene and schizophrenia; however, these results remain inconclusive. We investigated the possibility of an association between schizophrenia and CAG repeats in the hKCa3 gene in 127 unrelated Japanese schizophrenia patients and 84 controls highly matched for age and sex. No significant results were obtained with an allele dichotomization model (w2 ¼ 1.917, df ¼ 1, P ¼ 0.166). The overall distributions of allele frequencies were not significantly different between schizophrenia patients and controls (MannWhitney U test: P ¼ 0.606). In addition, we tested the relationship between the hKCa3 gene and genetic anticipation. A possible correlation between longer allele size and age at onset (AO) was explored using Spearman’s correlation coefficients. We found no correlation (n ¼ 127, r ¼ 0.023, P ¼ 0.796). We compared the numbers of CAG repeats in three groups: (1) 19 parent-offspring schizophrenia groups in which the AOs of the offspring were about 10 years earlier than the parents’ (transmitted alleles were selected), (2) 92 non-familial schizophrenia groups (alleles were selected at random), and (3) 84 normal controls (at random). No differences were found among the three groups (Kruskal Wallis test: P ¼ 0.662). P275 NO ASSOCIATION BETWEEN DBH-1021 C/T VARIANT AND SCHIZOPHRENIA Jo¨nsson EG,1 Aboujamra R,2 Schumacher J,2 Flyckt L,3 Edman G,4 Forslund K,1 Mattila-Evenden M,1 Rylander G,1 ˚ sberg M,1 Bjerkenstedt L,1 Wiesel F-A,5 Cichon S,2,6 A No¨then M,2,6 and Sedvall GC1 1 Department of Clinical Neuroscience, Psychiatry Section, HUBIN project, Karolinska Institute, Stockholm, Sweden 2 Institute of Human Genetics, University of Bonn, Germany 3 Jakobsberg-Karolinska Psychiatric Clinic, Stockholm, Sweden 4 Department of Psychiatry, Karolinska Institutet, Danderyds hospital, Sweden. 5 Department of Neuroscience, Psychiatry, Uppsala University Hospital, Sweden.

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Department of Medical Genetics, University of Antwerp, Belgium Disturbances in catecholamine transmission have been implicated in schizophrenia. Dopamine beta-hydroxylase catalyses the conversion of dopamine to norepinephrine in noradrenergic cells. We investigated a putative functional promoter polymorphism in the dopamine beta-hydroxylase gene (DBH) in schizophrenic patients (n ¼ 155) and control subjects (n ¼ 436). No significant difference was found. We conclude that the present results do not support a major involvement of the DBH gene in schizophrenia in the investigated Swedish population. P276 CATECHOL-O-METHYL-TRANSFERASE VAL108/158 MET GENE VARIANTS ASSOCIATED WITH PERFORMANCE ON THE WISCONSIN CARD SORTING TEST Joober R,1,4 Gauthier J,1 Lal S,1,4 Labelle A,2 Bloom D,1,4 Lalonde P,3 Rouleau G,1 and Benkelfat C4 1 Douglas Hospital Research Center 2 University of Ottawa, Canada 3 University of Montreal, Canada. 4 Department of Psychiatry McGill University Montreal, Canada. Because of its location in a region previously linked to schizophrenia (22q), and its critical involvement in the homeostasis of dopamine metabolism in brain regions relevant for schizophrenia, it was hypothesized that allelic variants of the Catechol-O-methyl-transferase (COMT) gene may modulate the risk for this disorder. As part of an ongoing research program on the genetics of schizophrenia, we recruited a group of unrelated schizophrenic patients (n ¼ 96) and a group of unrelated healthy volunteers (n ¼ 31) and assessed them with regard to neuropsychological performances using a battery of cognitive tasks which included the WCST. All these subjects were genotyped for the COMT gene Val108/158Met polymorphism. One way ANOVA, where the COMT genotype (Met/Met, Val/Met or Val/Val) and the WCST percent of perseverative errors were the independent and the outcome variables respectively, revealed a trend toward a significant effect of genotype on the WCST % of perseverative errors (F2, 122 ¼ 2.79, P ¼ 0.06), a measure thought to best reflect the level of performance in executive functions mediated by the DLPFC. These findings remained essentially unchanged when the analysis was restricted to schizophrenic patients (F2, 91 ¼ 2.71, P ¼ 0.07) but no genotype effect was observed when the analysis was restricted to controls. Although the frequency of the high activity allele was higher in schizophrenic patients (56%, n ¼ 104), compared to normal controls (50%, n ¼ 96), this difference was not statistically significant. These results replicate in part those of Egan et al.2001 and confirm that the COMT Val108/158 Met gene variants may be responsible for

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a small part of the variance for cognitive functions mediated by the dorsolateral prefrontal cortex. P277 ASSOCIATION STUDIES BETWEEN SCHIZOPHRENIA AND PHOSPHOLIPASE A2 GENES LOCATED ON CHROMOSOME 12 AND 22 Junqueira R, Jardim D, Cordeiro Q, Meira-Lima IV, Gattaz WF and Vallada H Department of Psychiatry, Sa˜o Paulo Medical School, Brazil Serum and plasma phospholipase A2 (PLA2) activity is increased in schizophrenic patients compared with healthy controls (Gattaz et al., 1987, 1990). The current study investigated two different polymorphisms in genes of the complex of PLA2. The first one is a trinucleotide ATT repeat in intron 1 of the secretory phospholipase (sPLA2) on chromosome 12q23-24.1, and the second one is a C-T substitution in intron 1 of the independent-calcium cytosolic phospholipase gene (iPLA2) located on chromosome 22q13.1. A casecontrol study using 240 unrelated Brazilian schizophrenic patients and 312 healthy control subjects was performed. Statistical analysis for allelic differences between cases and controls did not show statistical significance in the sPLA2 gene. In contrast, for the iPLA2 a statistically significant difference in allele frequencies between patients and controls was observed (w2 ¼ 5.4, 1df, P ¼ 0.02). The genotype distribution difference was marginally significant (w2 ¼ 5.9, 2df, P ¼ 0.05). The iPLA2 polymorphism was also investigated in a sample of 49 triads with schizophrenic probands, and the results showed preferential transmission of C allele (w2 ¼ 3.98 1df P ¼ 0.046). In conclusion our data suggests a possible association between this polymorphism in the iPLA2 gene on chromosome 22q13.1 and an increased risk for schizophrenia in our sample. This work was supported by FAPESP # 99/12360-2. P278 AN ALLELIC ASSOCIATION STUDY IN A UK CASE-CONTROL SAMPLE TESTING THE SCHIZOPHRENIA SUSCEPTIBILITY LOCUS ON CHROMOSOME 1q21-22 Kalsi G,1 Rizig MAA,1 Theobald S,1 Mcquillin A,1 Bass N,1 Curtis D,1 Pickard B,2 Blackwood D,2 and Gurling HMD1 1 Molecular Psychiatry Lab, Windeyer Institute of Medical Sciences, London, UK 2 Department of Psychiatry, Molecular Medicine Centre, University of Edinburgh, Western General Hospital, UK Genome scans in different populations have provided promising evidence in favour of schizophrenia susceptibility loci on chromosome 1q, including our own study using a linkage dataset of large multiply affected families. A highly significant result that has been replicated several times is the linkage study by Brzustowicz et al (2000), which reported a maximum heterogeneity LOD of 6.50. In our allelic association study, we tested the three most significant markers

(D1S1653, D1S1679, D1S1677) within the 20 cM distance highlighted by the Brzustowicz study. Furthermore, we extended our investigation to test a candidate gene in the region, KCNJ9, a member of the G-protein-activated inwardly rectifying potassium channel family. G-protein-activated K þ (GIRK) channels play an important role in neuronal firing rate. The four markers were genotyped in a stringently screened sample of 180 schizophrenic patients of English, Irish, Welsh or Scottish ancestry and allele frequencies were compared in an ethnically matched control sample of 310 individuals. An additional Scottish dataset of 83 schizophrenics and 95 ethnically matched controls was also genotyped and analysed. Data was analysed using the program CLUMP. Results for the combined sample were as follows: D1S1653: P ¼ 0.1800; D1S1679: P ¼ 0.1480; D1S1677: P ¼ 0.4850; KCNJ9: P ¼ 0.5860. These results are indicative of some support in favour of a susceptibility locus in the 10 cM region close to the markers D1S1653 and D1S1679. Clearly, fine-mapping with additional markers would be required and future work will be focused in this region. Reference: Brzustowicz LM, Hodgkinson KA, Chow EWC, et al. 2000. Science 288:678–682. P279 VULNERABILITY TO CANNABIS, SCHIZOPHRENIA AND THE (ATT)N POLYMORPHISM OF THE CANNABINOID RECEPTOR TYPE 1 (CNR1) GENE Krebs MO, Leroy S, Duaux E, Bourdel MC, Griffon N, Gorwood P, Loo H, and Poirier MF INSERM E0117, University Department of Psychiatry, Sainte-Anne Hospital, Paris, France Epidemiological studies have suggested that cannabis could precipitate schizophrenia in vulnerable subjects. We examined whether the susceptibility to psychotomimetic effects of cannabis could be related to the gener variants of CN1R. In a French Caucasian population, we assessed 102 schizophrenic patients, 85 non-schizophrenic opiate-addict subjects (all abuser of or dependent on cannabis) and 89 controls with a standardized interview (DSMIV criteria). Schizophrenic patients whose symptoms had been triggered or exacerbated in a context of cannabis consumption or misuse were defined ‘cannabis sensitive’ (CSS) patients. CSS patients had significantly more positive schizophrenic symptoms than nonCSS patients, even after adjustment on age and exclusion of recent users (less than one year) (P < 0.001). There were no difference in allele or genotype distribution between the whole group of schizophrenic patients and controls. By contrast, a significant lack of the allele 8 of the (ATT)n polymorphism of the CN1R was found in CSS patients when compared to the remaining patients (exact P ¼ 0.0028) or to controls (exact P ¼ 0.014). Interestingly, non-schizophrenic addict patients were not different from controls (exact P ¼ 0.13). Our results support the hypothesis that CNR1

Abstracts

receptor gene variants could predispose to the psychotomimetic effects of cannabis, precipitating vulnerable subjects in a positive form of the schizophrenia. Acknowledgment: This work received financial support from INSERM and Projet Cabanis (Pfizer France). P280 POLYMORPHISM SCREENING OF THE NEUROTROPHIN RECEPTOR P75 GENE AND ASSOCIATION ANALYSIS WITH SCHIZOPHRENIA Kunugi H1,2 and Nanko S1 1 Department of Psychiatry and Genome Research Center, Teikyo University School of Medicine, Tokyo, Japan 2 Department of Mental Disorder Research, National Institute of Neuroscience, Tokyo, Japan Based on both neurodevelopmental and neurodegenerative hypotheses in the etiology of schizophrenia, neurotrophic factors and their receptors may be involved in the pathogenesis of schizophrenia. In line with this, we previously reported a possible association between polymorphisms of the BDNF and NTF3 genes and the disorder. Here we go on to search for polymorphisms in the neurotrophin receptor p75 gene for genomic DNA from patients with schizophrenia. Currently we finished screening approximately 80% of the exonic regions by direct sequencing of PCR products, and found one silent and one missense nucleotide substitution. Then we performed an association analysis with respect to the missense polymorphism in a Japanese sample of 116 schizophrenics and 152 controls, matched for sex and age distributions. However, there was no significant difference in the genotype or allele frequency between the two groups, suggesting that the examined missense polymorphism is unlikely to play a major role in giving susceptibility to schizophrenia. P281 AUDITORY N1, N2, P3 IN PARENTS OF PATIENTS WITH SCHIZOTYPAL AND SCHIZOAFFECTIVE DISORDERS Lebedeva I, Orlova V, Kaleda V, Bondar V and Abramova L National Mental Health Research Center, Moscow. Russia It is established that some components of auditory eventrelated potentials (ERP) are similarly changed in patients with schizophrenia and their first-degree relatives. So, they are put under consideration in the search of endophenotypes of the disease. It is also known that similar ERP abnormalities are seen both in schizophrenics and patients with schizotypal and schizoaffective disorders. However, little is known about the latter’ relatives. To clarify the problem, preliminary study has compared parents of patients with schizotypal and schizoaffective disorder with parents of schizophrenics and a control group of mentally healthy subjects from unaffected families (diagnostics for patients done by ICD-10). All investigated parents comprised 14 right-handed subjects and were matched for age, sex and education. All parents of

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patients were from families without ancestors and other relatives with schizophrenia spectrum and affective disorders. Amplitudes and latencies of N1, N2 and P3 (recorded in standard oddball paradigm) were analyzed. Significant differences (P < 0.05) were found only between parents of schizophrenics and controls: the former had prolonged N2. No ERP abnormalities were observed in parents of patients with schizotypal and schizoaffective disorders; the relatively small sample size, however, as well as the absence of familal loading with disease may have obscured possible differences. P282 EVALUATION OF LINKAGE EVIDENCE OF SCHIZOPHRENIA TO CHROMOSOME 22q11-12 IN TAIWANESE FAMILIES Liu C-M,1 Hwu H-G,1 Ou-Yang W-C,2 Jann H-Y,3 Chen J-J,3 Lee SF-C,3 Hong C-J4 and Fann CS-J5 1 Department of Psychiatry, College of Medicine, National Taiwan University, Taipei, Taiwan 2 Institute of Public Health, National Yang-Ming University; Chia-Nan Psychiatric Center, Department of Health, Tainan, Taiwan 3 Taoyuan Psychiatric Center, Taoyuan, Taiwan 4 Department of Psychiatry, Veterans General Hospital, Taipei, Taiwan 5 Institute of Biomedical Science, Academia Sinica, Taipei, Taiwan Linkage evidence of schizophrenia to markers at chromosome 22q11-13 were reported in several studies. We intended to evaluate linkage evidence of schizophrenia to chromosome 22q11-13 in 106 Taiwanese schizophrenic families with at least two affected siblings. Two phenotype models (narrow: DSM-IV schizophrenia only; and broad: including schizophrenia, schizoaffective, and other non-affective psychotic disorders) were used to define the disease phenotype. To this date, we have genotyped 3 microsatellite markers over this region. Maximum non-parametric linkage (NPL) scores of 1.53 (P ¼ 0.05) and 1.04 (P ¼ 0.14) were obtained at the marker D22S156 under broad and narrow model, respectively. The marker is near the distal part of the 22q microdeletion region. We are continuing to genotype more markers at the proximal side, in the 22q microdeletion region. P283 HAPLOTYPE LINKAGE DISEQUILIBRIUM ANALYSIS Macciardi F Department of Medical Genetics, University of Milano & University of Toronto, Milan, Italy The aim of our study was to detect a possible susceptibility gene for schizophrenia on 22q12-13. Given that schizophrenia is a complex genetic trait and that consequently a susceptibility gene only conveys a small portion of the overall genetic risk, we adopted a case-control Linkage Disequilibrium strategy to detect a possible effect of such a locus, if

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existing. We analyzed 2 separate and independent populations, respectively from the Azores Island and Coimbra (Portugal) and Ontario (Canada): diagnosis of schizophrenia was made according to the DSM IV criteria, following a DIGS (Portugal) or a SCID-R interview. We collected 158 (P) and 189 (C) cases with matched controls. All patients and controls signed an informed consensus. We then typed 11 polymorphisms (5 microsatellites and 7 SNPs) on 22q12-13, covering a quite large area of about 5 cM. As expected considering their different evolutionary history, an analysis of the marker to marker LD in both cases and controls, showed different patterns in the 2 populations, requiring an independent haplotype-disease association strategy. To detect the possible effect of an etiologic gene of small effect on schizophrenia and to reduce the high variability of the extant haplotypes, we applied a haplotype analysis by also looking at the founding haplotypes in the 2 populations separately using the program DHSMAP [Mc Peek and Strahs, 1999]. Despite, the haplotypes in the Portuguese and in the Canadian populations were different, reflecting their different genetic background, in both cases we obtained the same exact and significant location for a putative susceptibility gene for schizophrenia, strongly supporting the hypothesis a true etiological genetic component for the disease exists in the area. Acknowledgment: This work has been supported by a NARSAD Independent Investigator Award to FM, 2001 Essel Investigator.

P284 TWIN CONCORDANCE FOR SCHIZOPHRENIA Machin PE, Farmer AE and McGuffin P The Social, Genetic and Developmental Psychiatry Research Centre, The Institute of Psychiatry, Kings College London, UK An important consideration in behavioural genetic research is how broadly to define schizophrenia and whether any other related disorders should be included within the phenotype. Schizophrenia shares a number of symptoms with other related disorders such as schizotypal personality disorder, affective disorder with psychosis and mood incongruent delusions, schizoaffective disorder and atypical psychoses. These disorders may be phenomenologically similar to schizophrenia, leading to the suggestion that they may be considered a variant of the same phenotype. Thus the effects of broadening the schizophrenia phenotype to include other related disorders will indicate the optimum definition of schizophrenia for genetic research. By applying the full range of possible Research Diagnosis Criteria (RDC) diagnoses to the probands and co twins from the Maudsley Hospital schizophrenic twin series, we calculated the effects of various combinations of diagnoses on the monozygotic to dizygotic (MZ/DZ) concordance ratio. The twin series was comprised

of 106 monozygotic and 118 dizygotic twin pairs. The highest MZ/DZ concordance ratio was found for schizophrenia alone (8.73), broadening the phenotype to include other related disorders resulted in a lowering of the ratio. These findings contrast with previous reports that the addition of affective disorder with mood incongruent delusions to the schizophrenia spectrum produces a large increase in the MZ/DZ concordance ratio (Farmer, McGuffin & Gottesman, 1985). However, the previous study used DSM III diagnoses and it remains to be seen whether the similar findings will occur in the current data when DSM III, rather than RDC diagnoses are used.

P285 INVESTIGATION OF MUSCARINIC 1 PROMOTER POLYMORPHISMS ON RECEPTOR EXPRESSION AND OUTCOME TO ANTIPSYCHOTIC TREATMENT Mancama D,1 Mata I,2 Munro J,1 Osborne S,1 Arranz MJ,1 and Kerwin R1 1 Section of Clinical Neuropharmacology, Institute of Psychiatry, London, UK 2 Fundacion Argibide, Pamplona, Navarra, Spain Muscarinic acetylcholine 1 (CHRM1) receptors are widely expressed within the brain, with particularly high densities found in those cortical and limbic regions thought to be important to the etiology of schizophrenia. Significant reductions in CHRM1 receptor density have been demonstrated in these regions among patients, and we reported comparable decreases in the levels of frontal cortical CHRM1 mRNA expressed in such individuals. We have examined putative CHRM1 promoter sequences for genetic alterations that may influence gene expression and, of those discovered, have identified significant association between a novel Tsp45I polymorphism and levels of receptor mRNA. Increased muscarinic activity has been proposed to exert a protective influence on the emergence of positive symptoms in schizophrenia, while a decrease in activity may impart an increase in positive symptoms. To investigate this potential, we have examined the CHRM1 polymorphisms in olanzapine treated patients prospectively rated for response according to PANSS and GAF. We have also investigated the potential influence of these polymorphisms on outcome to clozapine treatment. No association however has been observed between genotype at the Tsp45I polymorphism and improvement in either positive or negative symptoms during treatment (significance P ¼ 0.75; P ¼ 0.58 respectively). Similarly no association has been found between the promoter polymorphisms and overall response to clozapine and olanzapine. Our results suggest that CHRM1 promoter polymorphisms do not appear to influence outcome to clozapine or olanzapine treatment, though may be relevant to the expression of this receptor in frontal cortical tissue.

Abstracts

P286 CHROMOSOMAL ABNORMALITIES IN SCHIZOPHRENIA Martı´n B,1 Miro´ R,2 Salgado P,3 Catala´n R,4 Barrantes-Vidal N,5 Guitart M,1 and Fan˜ana´s L1 1 Unitat d0 Antropologia, Facultat de Biologia, Universitat de Barcelona, Spain 2 Dept. de Biologia Cellular, Universitat Auto`noma de Barcelona, Spain 3 Institut Municipal de Psiquiatria d0 Urge`ncies, Barcelona, Spain 4 Centre de Salut Mental Esquerra de l’Eixample, Hospital Clı´nic i Provincial de Barcelona, Spain 5 Dept. Psicologia de la Salut, Facultat de Psicologia, Universitat Auto`noma de Barcelona, Spain Cytogenetic approaches in psychiatric disorders have been demonstrated to be a useful tool to locate candidate genomic regions for molecular genetic studies in these complex disorders. The nature of chromosomal abnormalities reported in the literature for schizophrenic patients is wide. The aim of the present study was to explore the presence of three different types of chromosomal abnormalities in these patients: i) spontaneous numerical and structural anomalies, ii) spontaneous chromosomal breakage, and iii) telomeric associations. A preliminary sample of thirty unrelated patients meeting DSM-IV criteria for schizophrenia or schizophreniform disorder were analyzed. Fifteen healthy controls with the same age and sociodemographic profile were included for comparisons. A number of 683 and 359 metaphases in the case and control group respectively were examined (mean number per individual: 23.66, SD ¼ 2.96). i) The percentage of metaphases showing spontaneous numerical or structural abnormalities was similar in cases and controls. ii) Spontaneous fragile site expression (defined as the presence of gaps and breaks) was higher in patients than in controls, although this did not reach the significance level (6.7% vs 3.8%, P ¼ 0.08). iii) Patients showed a tendency to present more telomeric associations than controls (3.1% vs 1.3%). Spontaneous chromosomal breakage and telomeric associations may be of interest for the better understanding of the heterogeneous etiology of schizophrenia. These analysis will be extended to a bigger sample of cases and controls in order to confirm their relevance. Acknowledgements: This project was supported by Fundacio´ ‘La Caixa’ (99-111-00). P287 GLUTAMATE RECEPTOR GENES IN SCHIZOPHRENIA: TDT AND CASE-CONTROLS ANALYSES Martucci L, Wong AHC, Trakalo J, Cate T, Kennedy JL, and Macciardi FM Neurogenetics Section, CAMH, Clarke Division, University of Toronto, Ontario, Canada The N-Methyl-D-Aspartate Glutamate receptors (NMDAR) play critical roles in excitatory synaptic transmission, plasti-

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city and excitotoxicity in the CNS, and act as regulators of the release of neurotransmitters such as dopamine, noradrenaline, acetylcholine and GABA. It has been suggested that a weakened glutamatergic tone increase the risk of sensory overload and of exaggerated responses in the monoaminergic system, which is consistent with the symptomatology of schizophrenia. A variety of NMDAR subunits have been identified, and NMDAR functional properties are determined by subunit composition. NR1 is the only subunit that is expressed in all NMDA receptors. We focused on the study of two polymorphisms in the NR1 subunit gene (GRIN1): GRIN1/1 is a C/G substitution localized on the 50 untranslated region; GRIN1/10 is an A/G substitution localized in exon 6 of GRIN1. We genotyped 86 nuclear families and 91 ethnically matched case-control pairs. Both samples were collected from the Toronto area. We tested for the presence of an association between GRIN1 and schizophrenia using a case-control and family-based association strategy. The results are as follows: for the case-control sample: GRIN1/1: Ch1-square ¼ 0.013, P ¼ 0.908; GRIN1/10: Chi-square ¼ 0.544, P ¼ 0.461. For the nuclear families sample: GRIN1/1, Chi-square ¼ 2.19, P ¼ 0.14; GRIN1/10, Chi-square ¼ 1.5, P ¼ 0.22. Haplotype analyses showed a borderline significant result for the G/G, A/G haplotype (Chi-square ¼ 3.86, Pvalue ¼ 0.049). An analysis of variance was conducted to test the association between specific genotype groups and age at onset. No significant results were observed: GRIN1/1, F[df ¼ 2] ¼ 0.42, P-value ¼ 0.659; GRIN1/10, F[df ¼ 2] ¼ 0.16, P-value ¼ 0.853. We are currently enlarging our samples to increase the power of the analyses. P288 MOLECULAR CLONING, SEQUENCING, AND CHARACTERIZATION OF A NOVEL 500 KILOBASE GENE (MRDS1) FROM 6p24, A SCHIZOPHRENIA CANDIDATE REGION Matsumoto M, Weinberger DR and Straub RE Clinical Brain Disorders Branch, National Institute of Mental Health, NIH, Bethesda, Maryland Multipoint linkage analysis (ref.1) and family-based association analysis (ref.2) have implicated the 6p22.3 gene dysbindin (DTNBP1), and have also pointed to region 6p24. Based on computational annotation of the 1 megabase surrounding the associated 6p24 SSLP marker (D6S940), we searched the databases for non-repetitive ESTs. We found only one bovine spliced EST (AW428148) and one human spliced EST (BG185938). The next closest EST is AA256589, 540 kb distal. After PCR confirmation that the bovine exons were transcribed in human brain, we performed a combination of RT-PCR and RACE experiments to try and isolate and sequence full-length cDNAs from brain and peripheral tissues. ORFs of 204 amino acids in placenta and 300 amino acids in brain were found. This novel gene, MRDS1, contains more than 24 exons, and spans more than

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500 kb (130 kb distal to and 370 kb proximal to D6S940). Numerous splicing variants were evident, and exon prediction programs failed to predict many of the exons. All confirmed human splicing variants share four N-terminus exons in common, encoding 115 amino acids that correspond to part of the bovine EST. These exonic DNA sequences are also conserved in mouse, and the mouse ortholog shows 77% amino acid identity with the predicted human protein. However, the potential proteins show no obvious similarity to known proteins, and have few predicted motifs. MRDS1 transcripts containing these common exons were detected by RT-PCR in human brain (hippocampus, substantia nigra and frontal cortex) and several peripheral tissues. The spliced human EST (BG185938) is located 110 kb distal to D6S940, ie. it is within MRDS1, and it is transcribed in the opposite direction. We think that if the LD signal from D6S940 is true, then both genes should be considered strong schizophrenia positional candidates. References: 1) Straub et al. Molecular Psychiatry, in press, 2) Straub et al., Am J Human Genet, in press). P289 A GENOME SCAN OF EXTENDED FRENCH CANADIAN FAMILIES AFFECTED BY SCHIZOPHRENIA OR BIPOLAR DISORDER REVEALED COMMON AND SPECIFIC SUSCEPTIBILITY LOCI Maziade M, Chagnon Y, Roy MA, Fournier A and Me´rette C Centre de recherche Universite´ Laval Robert-Giffard, Que´bec, Canada Following our formerly published scan of 13 candidate chromosomes [Maziade et al., 2001], we have completed a full genome scan in a first sample of 21 large SZ and BP pedigrees (sample 1; N ¼ 480). This scan yielded strong linkage results, several of which are congruent with those of other international studies and deserve further investigation. In particular, we identified two linkages in 18q21.1 (Zmax of 4.46 and 4.03) which met our stringent threshold for significance, and one which reached the confirmatory threshold of linkage in 6p22.3 for SZ (Zmax of 3.47) (Maziade et al., 2002). Five other loci showed suggestive evidence of linkage: Zmax of 3.35 for BP in 15q11.1, Zmax of 3.30 for BP in 16p12.3, Zmax of 2.81 for SZ in 18q21.1, Zmax of 2.68 for BP in 3q21.2. Eight other linkage signals (1.9 < Zmax < 2.6) were obtained. These results support our original hypothesis that some linkages would appear common to SZ and BP (18q21.1 and 3q21) whereas others would be specific to either SZ (6p22.3) or BP (15q11, 16p12). The common phenotype definition for SZ and BP that we used to verify this common locus hypothesis was in fact the one leading to our best linkage result (Zmax of 4.46 in 18q21.1). Our progress now leads us to formulate a model in which a few genes of strong effects may explain a large proportion of SZ and BP cases in subsets of families. This model contrasts with the

generally held notion that SZ and BP both result from the combined effect of multiple genes of small effect. The number of sizeable linkage findings within the same sample shows the potential of our sampling strategy and methods, and offers grounds for the study of a complex interplay among susceptibility loci. In addition, we have gathered a new sample (sample 2) of 25 pedigrees (N ¼ 500) from the same population that will allow a solid replication of results and will provide a sizeable increase in power when combined with our sample 1 (total N ¼ 980). P290 AN ASSOCIATION ANALYSIS OF THE APOLIPOPROTEIN L GENE FAMILY IN AN IRISH SCHIZOPHRENIA SAMPLE McGhee KA,1 *Corvin AP,1 Morris DW,1 Schwaiger S,1 Quinn J,2 Scully P,2 Morgan M,2 Waddington JW2 and Gill M1 1 Neuropsychiatric Genetics Group, Department of Genetics, Trinity College, Dublin, Ireland 2 Department of Clinical Pharmacology, Royal College of Surgeons, Dublin, Ireland Schizophrenia (SZ) is a severe chronic psychiatric disorder characterized by delusions, hallucinations, disorganized thoughts and cognitive deficits. The pathophysiology is poorly understood, but SZ is a complex genetic disorder of neurodevelopmental aetiology. Many putative susceptibility loci have been reported, and some have received support by replication (including the 22q12 locus). None of these replications are consistent, because of the difficulties inherent in analysing complex genetic disorders. A recent metaanalysis of 20 SZ genome scans (including 2, 300 patients) allows clearer interpretation of the linkage data. Nine SZ loci, including 22q meet traditional criteria for statistical significance. Neuropathological, imaging and gene expressions increasingly suggest that the pathophysiology of SZ involves abnormal synaptic plasticity and maintenance; glial cell dysfunction and neurotransmission/signal transduction anomalies. A recent gene expression study (Mimmack et al., 2002) demonstrated up-regulation of the apolipoprotein L family in SZ and replicated this finding in an independent sample. This gene family (apoL1-6) represent outstanding candidates for SZ association analysis: 1 The family, although only relatively recently identified, are high-density lipoproteins which play a role in cholesterol transport. 2 They are expressed in brain and are involved in modulating cell membrane function-which could be relevant both to signal transduction and synaptic plasticity. 3 The family map to the chromosome 22q SZ susceptibility locus. Details will be presented of an apoL1-6 association analysis in a sample of Irish schizophrenia cases matched with population controls. We will present data on individual SNPs and haplotypes constructed across the genes.

Abstracts

P291 TEMPERAMENT IN SCHIZOPHRENIC PATIENTS AND THEIR FIRST DEGREE RELATIVES: A STUDY OF THE TRIDIMENSIONNAL PERSONNALITY QUESTIONNAIRE (TPQ) Me´ary A,1,2 Szo¨ke A,1,2 Schu¨rhoff F,1,2 Roy I,1,2 Bellivier F,1,2 Rouillon F1,2 and Leboyer M1,2 1 Service de psychiatrie adulte, Hoˆpital Henri Mondor et Albert Chenevier, AP-HP, Cre´teil, France 2 INSERM U 513, Laboratoire Neurobiologie et Psychiatrie, Faculte´ de Me´decine Henri Mondor, Cre´teil, France The aim of this study was to assess dimensions of temperament as defined by Cloninger’s neurobiological model using the TPQ in a sample of consecutively recruited schizophrenic patients and their first degree relatives. We used the French version of the TPQ to compare 50 stable, euthymic schizophrenic patients (SP), 86 of their first degree relatives (S-Rel) with no schizophrenia spectrum disorders and 175 controls (NC) with no personal or familial history of psychiatric disorder. The scores for the 4 TPQ’s scales were calculated for each group. We then performed a multivariate analysis using a general linear model to assess group influence on TPQ scores while avoiding the confounding effects of age and gender. For dimensions showing a significant difference between the three groups we performed a correlation analysis between SP and S-Rel scores. This analysis, which assessed familiality of TPQ’s dimensions, was realised in a subset of 25 independent case-relative pairs. Harm Avoidance (HA) was the only dimension for which the group effect was significant (P < 0.0001). HA was higher in SP (Mean ¼ 21.8  6.66) than in S-Rel (Mean ¼ 13.79  7.15) and in NC (Mean ¼ 11.02  5.49). All the differences between groups (SP vs S-Rel and NC, S-Rel vs NC) were statistically significant while correcting for multiple comparisons. We found no correlation between the SP and the S-Rel HA scores (r ¼ 0.13). This replicates previous studies suggesting that schizophrenic patients have high HA. Schizophrenic relatives also have slightly elevated HA, this could suggest that this dimension is a marker for underlying genetic vulnerability to schizophrenia, although the absence of correlation between SP and S-Rel on a small sample is against it.

P292 CLUSTER ANALYSIS OF SCHIZOPHRENIA PATIENTS USING LIFETIME DIMENSIONS OF PSYCHOSIS Medina R,1,2 Escamilla M,1 Dassori A,1 Contreras S,1 Levinson D,3 Raventos H,4 Montero P,4 Balderas T,1 Ontiveros A,5 Nicolini H,6 Mendoza R,7 Camacho A,8 and Delgado A7 1 University of Texas Health Science Center, San Antonio, Texas 2 South Texas Veterans Health System, San Antonio, Texas

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University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 4 Universidad de Costa Rica, Costa Rica 5 Universidad de Nuevo Leon, Monterrey, Mexico 6 Instituto Nacional de Psiquiatria, Mexico City, Mexico 7 University of California at Los Angeles, Los Angeles, California 8 University of California at San Diego, San Diego, California Despite extensive efforts for mapping genes for schizophrenia (SC), results are still inconclusive. Current categorical diagnostic systems allow different diagnoses to be assigned to subjects who differ only slightly in symptoms and course, while the same diagnosis may be applied to subjects having little resemblance. We used the Lifetime Dimensions of Psychosis Scale (LDPS), which encompasses positive, negative and disorganized symptom factors, plus moodrelated symptomatology, and degree of deterioration, to analyze how subjects cluster according with their lifetime dimensions of psychosis. We studied 114 patients clinically diagnosed with SC in Costa Rica, Mexico, and the US. Consensus best estimate diagnosis (CBED) and LDPS ascertainment were based on the DIGS, FIGS, and abstracts of clinical records. LDPS ratings were used for hierarchical cluster analysis. Only 84 subjects met DSM-III-R CBED of SC, while 3 were schizoaffective depressed, 11 with schizoaffective bipolar (SCAB), and 11 with bipolar disorder (BP). Most of patients diagnosed with SC grouped together in Cluster 4 (72%), but 12 (16%) fell into Cluster 2 (where most of SCAB and BP patients clustered). Comparison of DSMIII-R diagnoses with obtained clusters showed low but significant correlation (symetric lambda ¼ 0.18, P ¼ 0.044). Patients diagnosed with SC grouped together in three different clusters suggesting an inherent heterogeneity uncovered by lifetime dimensions of psychosis. P293 STUDIES OF SCHIZOPHRENIA IN COSTA RICA Mese´n A,1 Rodrı´guez C,1 Laprade B,1 Llach M,1 Bertheau A,1 Riondet S,1 and DeLisi LE2 1 The Psychiatric Genetics Research Center, San Jose´, Costa Rica and Hospital Nacional Psiquia´trico, Pavas, San Jose´, Costa Rica. 2 The Department of Psychiatry, New York University Since 1996 we have been evaluating families with multiple affected individuals with schizophrenia in Costa Rica. Approximately 160 such families have been identified thus far. With the aid of a geneologist, pedigrees were reconstructed and 3 large families appear to be originate from common founders and are composed of several of the previously thought to be unrelated nuclear families. Costa Rica is a small country located in Central America. The first large family under study is mostly located in Grecia, a small portion of the province of Alajuela. Two Hispanic founders of this family

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were identified; one who is only mentioned in the National Archives in 1780, and the other from who we know when and where he was born in Spain (Granada, 1610). Using the DIGS, Medical Records and the RPHQ, we have been able to identify that 18 patients (10 alive, 8 deceased) meet the criteria for Schizophrenia, 6 for Schizoaffective Disorder (4 alive, 2 deceased), 1 for Psychosis NOS (alive), 1 for Depression with Psychosis (alive), 1 for Bipolar Disorder (alive), 7 for Major Depression (6 alive, 1 deceased) and 14 with unknown diagnosis. Blood samples have been drawn from ill and well individuals for future genetic analysis. Currently, MRI scans are being done in all available members of the family for phenotype analysis, as well as a 15-individual control group with matching Hispanic origin, age and sex. All individuals are also being assessed with a neuropsychological test battery. The initial genome scan on the first 100 nuclear families yielded no significant results (in press, Neuropsychiatric Genetics). The highest lod score was on chromosome 5q, but only reached a peak score that was less than 2.0. Further work will be performed to analyze the extended families using the intermediate biological phenotypes, as well as the diagnosis of schizophrenia, in the analyses. P294 POSITIONAL CLONING OF SCHIZOPHRENIA-RELATED GENES ON CHROMOSOME 15q14-15 Meyer J, Schraut K, Johannssen K, Ortega G, Reif A, and Lesch KP Department of Psychiatry and Psychotherapy, University of Wuerzburg, Germany Schizophrenia is commonly regarded as a complex disorder and affects about 1% of the population. However, a separate entry in the Online Mendelian Inheritance in Man Database (OMIM) has been created for chromosome 15 related, hereditary, catatonic schizophrenia (SCZD10, OMIM 605419), which is inherited in an autosomal dominant manner. A possible role of the chromosome 15q14-15 region in the pathogenesis of schizophrenia and manic depressive disorder has recently been reported by several scientific groups. We have recruited two multiplex families affected with SCZD10; both families support strongly the chromosome 15 locus. An 8 centiMorgan region between genetic markers D15S1042 and D15S182 is shared by the affected members of both families. A number of genes expressed predominantly in the brain, and localized adjacent to this chromosomal region are excluded from the candidate gene panel by mutational analysis and fine mapping data. These include genes encoding the nicotinic a7 receptor subunit, the potassium-chloride cotransporter 3, the ryanodine receptor 3, and connexin 36. All these proteins are important factors for brain development and function. Other genes, like the gene encoding the member of the SNARE (soluble N-ethyl maleimide-sensitive

factor [NSF] attachment protein [SNAP] receptor)-complex SNAP23, remain potential candidates. We are currently narrowing down the region of interest by investigating more families and defining the gene (s) responsible for the disease by mutational analysis. P295 ANTICIPATION OF PATIENTS WITH SCHIZOPHRENIA AND COURSE OF THE DISEASE Mimica N, Henigsberg N, Vilibic M and Folnegovic-malc V University Department of Psychiatry, Psychiatric Hospital Vrapce, Zagreb, Croatia In this study, which was performed in Psychiatric Hospital Vrapce, Zagreb, Croatia, only those patients with schizophrenia who were admitted during 1996 for the first time in their life were included. Data were analysed according to following characteristics: gender; age at first hospitalisation; heredity (based on anamnestic and heteroanamnestic sources); type of schizophrenia and prognosis of illness. Prognosis evaluation was based on number of hospitalisations as well as on number of total inpatient days. At the end of the year 2001, after a 6-year follow-up, results showed a much better prognosis in patients with negative heredity and in those patients that were older at initial hospitalisation. Namely, in the group of patients with positive heredity the onset of the disease was statistically significant earlier; the catatonic subtype of schizophrenia occured less frequent than the simplex and hebefrenic subtypes. Those patients remain more frequent single, have less children, and less self-made income. Also, these patients spent higher persentage of time in hospital than those with negative heredity. So, the results of this study support the anticipation in schizophrenia. P296 IS SCHIZOPHRENIA GENETIC LIABILITY IMPORTANTLY WEIGHTED BY GLIAL ASTHENIA? Moises HW,1 and Gottesman II2 1 Department of Psychiatry, Kiel University Hospital, Germany 2 Departments of Psychiatry and Psychology, University of Minnesota, Minneapolis Genome scans and linkage studies have revealed several potential and significant chromosomal locations for schizophrenia susceptibility genes. Based on a convergent loci approach and a large amount of circumstantial evidence, we propose that a functional deficiency of glial growth factors and of growth factors produced by glial cells may be one of the distal causes in the genotype-to-phenotype chain leading to the development of schizophrenia. The hypothesis suggests that glial cells might be the locus of the genes-environment interactions in schizophrenia and that the genetic liability to the disorder is importantly weighted by glial asthenia. Reference: Moises HW, Zoega T, Gottesman II

Abstracts

[2002] The glial growth factors deficiency and synaptic destabilization hypothesis of schizophrenia (submitted). P297 ASSOCIATON OF TUMOR NECROSIS FACTOR ALPHA GENE -G308A POLYMORPHISM WITH SCHIZOPHRENIA Mondabon S,1 Schwab SG,1 Knapp M,2 Albus M,3 Hallmayer J,4 Borrmann-Hassenbach M,3 Lerer B,5 Maier W,6 and Wildenauer DB1 1 Molecular Genetics Laboratory, Department of Psychiatry, University of Bonn, Germany 2 Department of Medical Statistics, University of Bonn, Germany. 3Mental State Hospital, Haar, Germany 4 Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Palo Alto, California 5 Department of Psychiatry, Hadassah- Hebrew University, Jerusalem, Israel 6 Department of Psychiatry, University of Bonn, Germany Tumor necrosis factor alpha (TNFa), a cytokine involved in inflammatory processes, has been implicated in the pathophysiology of schizophrenia. The chromosomal location in the major histocompatibility complex (MHC) region on 6p21.1–21.3, a region with evidence for linkage, suggests a role in susceptibility to schizophrenia. In addition, association of the minor (A) allele of the -G308A TNFa gene polymorphism with schizophrenia has been reported. We studied association of the -G308ATNFa gene- and the lymphotoxinalpha (LTa) þ A252G gene polymorphisms with schizophrenia in 79 sib-pair families with linkage in the MHCregion and in 128 trio families using the transmission disequilibrium test (TDT). Biased transmission of the common G allele was detected for TNFa G308A in both samples independently, producing P ¼.003 in the combined samples, while LTa þ A252G, located approximately 2–3kb distally, revealed P ¼.03, and the two locus haplotype a P-value of .001. Our data suggests association of the common G allele of the G308A TNFa gene polymorphism with schizophrenia in a sample of 207 families, but linkage disequilibrium with a different allele of the TNFa gene or another gene in the MHC region cannot be excluded. P298 MINOR PHYSICAL ANOMALIES AND THE NEUROTROPHIC FACTOR GENE IN SCHIZOPHRENIA Mori T,1 Fujimaru K,1 Uraguchi M,1 Imamura A,1 Hashida A,1 Matsumoto S,2 Okazaki Y,3 and Nakane Y1 1 Department of Neuropsychiatry, Nagasaki University School of Medicine, Japan 2 Michino-o Hospital, Nagasaki, Japan 3 Department of Neuropsychiatry, Mie University School of Medicine, Tsu, Japan

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We assessed the prevalence of minor physical anomalies (MPAs) in schizophrenia patients (n ¼ 313) and normal controls (n ¼ 128) by using the modified Waldrop scale. There was a significant difference in Waldrop scale scores between the patients and controls (U ¼ 17274.5, P ¼ 0.02). Patients had significantly more MPAs than controls on Malformed ears (P ¼ 0.039), Soft and pliable ears (P ¼ 0.039), Furrowed tongue (P ¼ 0.006), and High steepled palate (P ¼ 0.041). There was a significant difference between patients and controls on head circumference, the average being 1.5 SDs lower in patients compared to normal controls (P ¼ 0.015). When the schizophrenia patients with Waldrop scores 3 (n ¼ 104) were compared with those with scores < 3 (n ¼ 208), there were significant differences in head circumference (U ¼ 8860.5, P ¼ 0.009) and distance between tear ducts (U ¼ 8448.0, P ¼ 0.003), though there were no significant differences in age (U ¼ 10423.5, P ¼ 0.601), onset age (U ¼ 10770.5, P ¼ 0.952), and height (U ¼ 10274.5, P ¼ 0.651). When the schizophrenia patients with Waldrop scores 3 or 4 were compared respectively with those with scores 0.05). We found a positive association between the 16 bp duplication in intron 3 of TP53 and schizophrenia (w2 ¼ 16.4466, df ¼ 2, P ¼ 0.0003 for genotypes; w2 ¼ 4.3431, df ¼ 1, P ¼ 0.0372 for allele frequencies). An overrepresentation of the genotype 16 bp duplication/duplication and allele 16 bp duplication emerged in schizophrenia patients compared to controls. No association was observed for the BstUI and MspI polymorphisms of TP53 in schizophrenia. Our results suggest that the 16 bp duplication in intron 3 of human TP53 may be associated with schizophrenia. Overall, our work also suggests that the differential screening of gene initiation sequences is a useful techniques to identify variations, which might be associated with complex genetic disorders in humans. P304 HELSINKI HIGH-RISK STUDY: A FOLLOW-UP STUDY OF 179 OFFSPRING OF MOTHERS WITH PSYCHOTIC DISORDER Niemi LT, Suvisaari JM, Haukka JK, Wrede G, and Lo¨nnqvist JK National Public Health Institute, Helsinki, Finland To study the occurrence of adulthood psychiatric disorders among offspring of mothers with psychotic disorder, and controls. Mothers are all female patients born between 1916 and 1948 and who had been treated because of schizophrenia, schizoaffective disorder, or schizophreniform psychosis in any of the mental hospitals of the city of Helsinki until the year 1974 and who had given birth in Helsinki between 1960 and 1964. Controls are the previous same-sex births from the same maternity hospitals. The current follow-up is based on the Finnish Hospital Discharge Register information on hospital treatments. All hospital and outpatient treatment records were collected and rated according to DSM-IV criteria. After diagnostic procedure, the mothers were divided into 4 HR groups: schizophrenia, schizoaffective disorder, other nonaffective psychoses, and affective disorders. The prevalence of psychiatric disorders among offspring of all these groups was calculated. The prevalence of any psychotic disorder among offspring of mothers with schizophrenia was 13.6%, among offspring of mothers with schizoaffective disorder 10.0%, among offspring of mothers with other

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schizophrenia spectrum psychosis 10.3%, and among offspring of mothers with affective disorder 4.0%. The prevalence of schizophrenia among offspring of mothers with schizophrenia was 5.8%. The risk of developing psychosis was approximately equal in the HR groups of mothers with schizophrenia, schizoaffective psychosis, and other. schizophrenia spectrum disorders. The observed prevalences are in the same range as those found for first-degree relatives in family studies and for adoptees having biological mothers with schizophrenia in adoption studies, but lower than in previous high-risk studies. P305 NIACIN FLUSH SKIN TEST IN PARENT-OFFSPRING TRIOS AFFECTED WITH PSYCHOSES Nikolov I,1 Poriazova N,2 Milev R,3 Toncheva D,1 and Kirov G4 1 Department Medical Genetics, Medical University Sofia, Bulgaria 2 Psychiatric Dispensary, Plovdiv, Bulgaria 3 Psychiatric Dispensary, Blagoevgrad, Bulgaria 4 Neuropsychiatric Genetics Unit, UWCM, Cardiff, UK Highly unsaturated fatty acids have been implicated in the pathogenesis of schizophrenia (SZ). Several studies have shown that SZ patients have reduced response to niacin, indicating an abnormality in the metabolism of fatty acids. We applied the test to 54 patients of Bulgarian origin and their parents.31 patients had SZ and 23 had bipolar or schizoaffective disorder (BP). The niacin was applied in four different concenrations (0.1, 0.01, 0.001, and 0.0001 M) on four pieces of blotting paper attached to a plastic strip. The strip was applied to the forearm of each participant for one minute. The skin reaction was rated according to a four-grade scale. Ratings were recorded at 5, 10, 15, and 20 minutes. A digital photograph was taken at 15 min and checked by a second rater. We used a global rating of the results of each concentration of niacin at every time point. We observed a clear sex difference: fathers had a mean of 8.6 points lower scores than their wives, 95% CI ¼ 4.4–12.8, P < 0.001). Female SZ (N ¼ 22) and male SZ probands (N ¼ 9) had lower levels than their mothers and fathers (1.1 and 1.6 points respectively), however the difference was not significant. BP females (N ¼ 17) had 5.18 points lower levels than their mothers (P ¼ 0.15). BP males (N ¼ 6) had 20.7 points higher levels than their fathers (P ¼ 0.011). There was no significant difference between the diagnoses, probably reflecting the small size of each subgroup. Future studies must consider males and females separately due to the strong sex difference in the test. Other factors affecting the test could be elucidated. Using parental controls we found a trend supporting reports that SZ patients have a reduced niacin skin flushing but a bigger sample will be required to confidently detect differences between diagnoses.

P306 MUTATION SCREENING OF THE HOMER GENE FAMILY AND ASSOCIATION WITH SCHIZOPHRENIA Norton N, Williams HJ, Williams NM, Spurlock G, Preece A, Zammit S, Jones G, Jones S, Owen R, O’Donovan MC, and Owen MJ Department of Psychological Medicine, UWCM, Cardiff, UK The Homer proteins are regulators of group 1 metabotropic glutamate receptors. We have determined the genomic structure of all three genes encoding Homer in silico and screened each for sequence variation in 14 unrelated individuals with schizophrenia. Allele frequencies of all SNPs detected were estimated in DNA pools of 368 schizophrenics and 368 controls. We found seven synonymous SNPs, of which Homer 1 IVS4 þ 18A > G was associated with schizophrenia, OR 1.4, CI 1.1-1.9, (P ¼ 0.01). IVS4 þ 18A > G was genotyped in a further sample of 315 cases and 313 controls. Rather than strengthened, the evidence for association in the combined sample of 680 cases and 671 controls was weakened, OR 1.2, CI 1-1.5, (P ¼ 0.05). We interpret this as suggesting that the initial finding is a chance positive, although as always, variable signal from weak genetic effects cannot be excluded. P307 MUTATION SCREENING OF THE METABOTROPIC GLUTAMATE RECEPTOR MGLUR7 (GRM7) GENE IN PATIENTS WITH SCHIZOPHRENIA Ohtsuki T and Arinami T Department of Medical Genetics, Institute of Basic Medical Sciences, University of Tsukuba, Japan Glutamate dysfunction has been implicated in the pathophysiology of schizophrenia. The metabotropic glutamate receptor mGluR7 is a G protein coupled receptor and has two alternative splice isoforms. mGluR7 mRNA is expressed in many regions of the human CNS, especially the cerebral cortex, hippocampus and cerebellum. The GRM7 gene is located on human chromosome 3p26, which has been suggested by a linkage study to contain a susceptibility locus for schizophrenia. In this study, we searched for mutations in the coding region of the GRM7 gene by direct sequencing in 24 Japanese patients with schizophrenia and evaluated associations between the detected polymorphisms and schizophrenia. We detected 16 polymorphisms: 222C/T (Asn74Asn), IVS1-76T/C, IVS1-66T/G, IVS1-23G/A, IVS4-35C/T, IVS5-20 (TG)13-17, 1298A/T (Tyr433Phe), 1575A/G (Leu525Leu), 1789C/T (Leu597Leu), 2196C/T (Tyr732Tyr), 2235G/A (Gly745Gly), IVS8 þ 49T/A, IVS8 þ 114T/ C, IVS8-123T/C, IVS9 þ 15G/A, 3363T/C. Case-control comparisons for genotype and allele frequencies of the detected polymorphisms and microsatellite markers, D3S1304 and D3S3728, which are located in this gene, resulted in no statistically significant differences. Genetic variations in the

Abstracts

GRM7 gene are not likely to contribute to genetic susceptibility to schizophrenia in the Japanese population. P308 LEFT SUBCORTICO-FRONTAL, LEFT SUBCORTICO-TEMPORAL AND SUBCORTICAL CHARACTERISTICS OF BRAIN REGIONS AS MULTIVARIATE NEUROPSYCHOLOGICAL PREDICTORS OF GENETIC RISK FOR SCHIZOPHRENIA Orlova V, Tsherbakova N, Korsakova N, Savina T, Yermakov I, and Sudakov S Mental Health Research Centre, Russian Academy of Medical Science, Moscow, Russia In order to study neuropsychological characteristics of brain function in schizophrenia patients and their first degree relatives and estimate their validity for the discrimination of high risk groups for schizophrenia 59 families were investigated (193 subjects: 59 schizophrenia—patients probands, 109 parents and 25 siblings). The control group comprised 23 subjects. Neuropsychological methods of Louria’s school were used. They included the analysis of functional peculiarities of cortico-subcortical, cubcortico-frontal, subcortico-parieto-occipital and subcortico-temporal brain regions of both hemispheres by parameters of audio-verbal and visual memory, praxis, gnosis, speech, attention. The results showed a wide spectrum of neuropsychological abnormalities for all studied brain regions of both hemispheres in patients and relatives as compares with controls. Multivariate integral characteristics of function of left and right subcortical, left subcortico-frontal and left subcortico-temporal regions were the most informative for the differentiation of the studied groups. Errors for the discrimination of subjects from the group of patients and controls (low genetic risk group—LRG) and LRG and siblings group (high genetic risk group) varied from 7 to 19%. The studied neuropsychological predictors can be used for the future development of complex criteria of genetic risk for schizophrenia. P309 GENOME SCAN OF SCHIZOPHRENIA, BIPOLAR DISORDER AND PSYCHOSIS IN PORTUGUESE FAMILIES Pato CN,1,2 Sklar P,3 Daly M,3 Verner A,3 Kirby A,3 Hudson T,3 Medeiros H,1 Morley CP,1 Macedo A,2 Dourado A,2 Coelho I,2 Valente J,2 Soares MJ,2 Ferreira CP,1,2 Carvalho C,1,2 Kennedy JL,1,4 Azevedo MH,2 Lander E,3 and Pato MT1,2 1 Center for Psychiatric and molecular Genetics, SUNY Upstate, Syracuse, New York 2 Universidade de Coimbra, Portugal 3 Whitehead Institute Center for Genome Research, Cambridge, Massachusetts 4 Clarke Division, Centre for Addiction and Mental Health, Toronto, Canada

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To identify genes for schizophrenia, bipolar disorder and psychosis, we have performed an initial genome-wide scan on 360 individuals from 67 multiplex Portuguese families mostly from island populations (85%). The island’s recent settlement in the 1500’s may be advantageous. We genotyped 391 markers (10 cM resolution approximately) with an average heterozygosity of 75%. Families were analyzed in three diagnostic categories: schizophrenia (DSM-IV diagnoses of schizophrenia and schiozaffective disorder depressed), bipolar disorder (DSM-IV bipolar disorder or schizoaffective manic) or psychosis (lifetime history of psychotic episode). Multipoint nonparametric linkage analysis using GENEHUNTER software was performed. In the schizophrenia families NPL scores of greater than 1.7 were obtained on chromosomes 1, 5, and 8. The regions on 1 and 5 also had NPL scores greater than 1.8 when all individuals with psychosis were considered regardless of disease phenotype. An additional chromosomal region was identified for psychosis on chromosome 11. In families with bipolar disorder, there were 6 chromosomal regions with NPL scores greater than 2.0 on chromosomes 2, 6, 9, 18, 19 and 20. We are currently fine mapping these regions in an additional 35 families to replicate previous findings and to characterize candidate genes in the region. Our observation of evidence for linkage common to schizophrenia and psychosis may indicate that genes in these regions play a role in both phenotypes, while other evidence for linkage appears to be specific for bipolar disorder and schizophrenia and not the common phenotype psychosis.

P310 MICROARRAY GENE EXPRESSION STUDIES OF PREPULSE INHIBITION, A SCHIZOPHRENIA ENDOPHENOTYPE Petryshen TL,1 Aldinger KA,1 and Sklar PB1,2 1 Whitehead Institute/MIT Center for Genome Research, Cambridge 2 Harvard Medical School, Charlestown, Massachusetts Our objective is to identify genes involved in prepulse inhibition (PPI) of startle by DNA microarray gene expression studies in inbred and consomic mouse strains. PPI is a phenomenon in which a weak sensory stimulus reduces the response to a subsequent startling stimulus. PPI is a measure of sensorimotor gating, a brain mechanism that filters extraneous stimuli to allow cognitive and motor centers to attend to relevant stimuli. Impaired PPI in schizophrenia patients suggests that gating deficits may underlie the disease etiology, thus are an endophenotype (risk factor) of schizophrenia. We are studying three inbred mouse strains, C57BL/ 6J, A/J, and 129SvEv, which are known to differ in PPI, and C57BL/6J. A/J consomic strains. Each consomic strain has a single A/J chromosome on a C57BL/6J genetic background,

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thus may have fewer gene interactions than the inbred strains, thereby improving gene detection. Twenty male mice from all strains are assessed for acoustic PPI, and results support significant PPI differences between C57BL/6J, A/J, and 129SvEv (P < 0.001). These three strains, and consomic strains that vary in PPI from the parental C57BL/6J strain, are undergoing further PPI testing with or without drug modulation of PPI. Immediately following testing, medial prefrontal cortex, hippocampus, striatum, and midbrain, regions involved in PPI, are removed for gene expression analysis using Affymetrix murine U74Av2 arrays (12,000 genes). Clustering algorithms are used to identify candidate PPI genes with significant differential expression between strains and drug treatment groups. Gene expression levels are confirmed by quantitative RT-PCR and in situ hybridization. SNP association studies in schizophrenia patient samples are planned for genes that map to PPI or schizophrenia susceptibility loci. We conclude that microarray studies of mouse strains that vary in PPI are feasible for identification of PPI genes, which may be important in schizophrenia etiology.

P311 FUNCTIONAL IMAGING OF VERBAL SELF MONITORING IN MONOZYGOTIC TWINS DISCORDANT FOR SCHIZOPHRENIA Picchioni MM, Chitnis XA, Fu CHY, Vythelingum N, Toulopoulou T, Williams SCR, Murray RM and McGuire PK Section of Neuroimaging, Division of Psychological Medicine, Institute of Psychiatry, London, UK Self-monitoring is a hypothetical system that discriminates internally generated events from those of external origin. Studies have shown that patients with schizophrenia positively misidentify their own distorted speech as originating from someone else. A failure of verbal self-monitoring has been proposed as a biological basis for auditory hallucinations in schizophrenia. We studied the neural correlates of verbal self-monitoring in five pairs of monozygotic (MZ) twins discordant for schizophrenia and four pairs of healthy MZ control twins using functional MRI. Subjects read aloud adjectives and heard either their own voice or their own voice distorted by a pitch change. Images were acquired at 1.5 T using a compressed acquisition sequence to allow task performance in the absence of scanner noise. Images were analysed using BAMM software (Institute of Psychiatry, University of London). Compared to the healthy control twins, when hearing their own voice distorted both the ill and well discordant twin groups showed a failure to activate the cerebellum, temporal pole bilaterally and superior temporal gyrus. Further deficits were detected in the ill discordant group in the hippocampus. Compared to their healthy cotwins, the schizophrenic twins showed a failure to activate the

cerebellum, hippocampal region and superior temporal gyrus bilaterally. On a task that hypothetically taps the neural substrate of a core psychotic symptom, we detected differences in cerebral activity between ill and well MZ twins discordant for schizophrenia and healthy control twins. These results suggest that abnormalities in a distributed cerebral network may be related to the experience of auditory hallucinations and that these deficits are at least partially genetic in origin. These abnormalities affect regions implicated in speech and language generation and perception.

P312 IDENTIFICATION AND GENOMIC STRUCTURE OF A HUMAN DTNBP1 GENE FROM A PUTATIVE SCHIZOPHRENIA SUSCEPTIBILITY LOCUS ON 6P22.3 IN SILICO Jiang Y,1 Straub RE,1 Sullivan PF,1 Harris-Kerr C,1 Webb BT,1 Wormley B,1 Wang X,1 Gibberman A,1 Cesare AJ,1 Chen X,1 O’Neill FA,2 Walsh D,3 Kendler KS,1 and Riley B1 1 Virginia Institute of Psychiatric and Behavioral Genetics, Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia 2 Department of Psychiatry, Queens University, Belfast, Northern Ireland. 3 The Health Research Board, Dublin, Ireland Schizophrenia is a relatively common, chronic and debilitating psychiatric disorder. It is highly heritable but the genetics are complex. Human chromosome 6p22.3 has previously been linked to schizophrenia in several studies. However, genes present in this region have not yet been investigated in detail. Here we report a full-length cDNA and genomic structure of the human dystrobrevin binding protein 1 gene (DTNBP1) identified between markers D6S260 and D6S1676 by an in silico pipeline and PCR from human brain cDNA libraries. Genome annotation revealed that human DTNBP1 spans 140 kb and has a putative promoter with features characteristic of housekeeping gene. We verified 10 exons in our transcript by direct sequencing. The corresponding cDNA is 1349 bp. The open reading frame encodes a 351-amino-acid protein that contains several conserved features: a coiled-coil region, a leucine-rich repeat and several protein kinase phosphorylation sites, which may indicate a role in intracellular signal transduction. It is a promising positional candidate gene for schizophrenia given its genomic localization and interaction with the dystrophin-associated protein complex (DPC) in brain. Three simple sequence repeats and 24 SNPs identified by database hunting and sequencing on pooled ISHDSF DNA samples are useful resources for further evaluating the candidate gene status.

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P313 DIFFERENCES IN MOUSE BRAIN MICROARRAY DETECTED GENE EXPRESSION PROFILES IN RESPONSE TO THE ANTIPSYCHOTIC DRUGS CLOZAPINE AND HALOPERIDOL: WHAT GENE EXPRESSION PATHWAYS MEDIATE CLOZAPINE’S SUPERIOR CLINICAL EFFICACY? *Rizig MA,1 McQuillin A,1 Fletcher D,2 Hubank M,3 Hunt SP2 and Gurling HMD1 1 Molecular Psychiatry Laboratory, Department of Psychiatry and Behavioural Sciences, Windeyer Institute, UCL, London, UK 2 Department of Anatomy and Developmental Biology, UCL, London, UK 3 Molecular Haematology Unit, Institute of Child Health, London, UK The atypical antipsychotic Clozapine has been found to produce a remarkably improved clinical response when compared to other antipsychotics. Clozapine can reverse and get rid of very resistant delusions. Patients often experience a state of positive well being without hallucinations and thought disorder and they experience few extrapyramidal side effects. Efforts to understand why Clozapine has such an improved clinical efficacy are in their infancy. Very little is known about the true therapeutic receptor targets of both the old and modern antipsychotics. The observation that antipsychotics cannot produce their positive clinical effect in less than two to three weeks suggests that the action of these drugs is mediated far more than just by simple receptor blockade. We have compared the expression profile in response to chronic treatment (4 weeks) of both clozapine and haloperidol in mouse brain using Affymetrix microarrays, which can detect changes in approximately 12,000 expressed genes. Genes which show a two or more fold increase or decrease in response to clozapine but not to Haloperidol have been identified as being correlated with the positive pharmacological effect of Clozapine. These genes are being further investigated, to confirm gene expression changes, by in situ hybridisation of mouse brain tissue. Genes implicated will be studied in terms of their chromosomal localization in relation to established susceptibility loci for schizophrenia and will be studied by case control allelic association studies and direct sequencing. P314 COMT GENE VARIABILITY AND PREFRONTAL NEUROCOGNITIVE FUNCTIONS IN DISCORDANT SIB PAIRS FOR SCHIZOPHRENIA SPECTRUM DISORDERS Rosa A,1 Zarzuela A,2 Cuesta MJ,2 Peralta V,2 Martı´nez-Larrea A,2 Serrano F2 and Fan˜ana´s1 1 Unitat d’Antropologia. Facultat de Biologia, Universitat de Barcelona, Spain 2 Psychiatric Unit Virgen del Camino Hospital, Pamplona, Spain

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Neurocognitive deficits of the dorsolateral prefrontal cortex have been consistently reported in schizophrenia. The COMT enzyme metabolises dopamine and could be an important factor modulating the execution of prefrontal tasks. A relationship between a functional COMT polymorphism, Val108/158Met, and performance on the Wisconsin Card Sorting Test (WCST), has been reported recently [Egan et al., 2001; Malhotra et al., 2002]. In the present study we have tested this polymorphism and two executive functions: i) The trail making test form b (TMTb) and ii) The WCST. The sample consisted in 89 Spanish sib-pairs discordant for schizophrenia and schizophrenia-related disorders (DSMIV). Affected sibs scored significantly worse compared to healthy sibs for the prefrontal cognitive variables analysed. The same association between COMT genotypes and the WCST-Perseverative errors reported by Egan and colleagues 2001, was found in the healthy group (P ¼ 0.04). However this association was not found in patients. A trend in the direction of the hypothesis (association in allele dosage to the performance of the test) was found for the TMT-B, although it does not reach the statistical level. Our results seem to confirm the interest of the COMT genotype in the modulation of the phenotype related with the dopaminergic function. Further studies will be necessary to clarify the specific risk of this gene for schizophrenia. References: 1. Egan et al., 2001: PNAS 12:6017–6922; Malhotra et al., 2002: Am J Psychiatry 159(4):652–654. Acknowledgements: This work was supported by the Vada and Stanley Foundation. P315 THE EFFECT OF THE IL-1ß GENE IN THE COMPLEX PHENOTYPE OF PSYCHOSIS Rosa A,1 Peralta V,2 Papiol S,1 Cuesta MJ,2 Serrano F,2 Martı´nez-Larrea A2 and Fan˜ana´s L1 1 Unitat d0 Antropologia, Facultat de Biologia, Universitat de Barcelona, Spain 2 Psychiatric Unit Virgen del Camino Hospital, Pamplona, Spain Schizophrenia (SZ) is a complex and severe disease affecting about 1% of the population. Twin and adoption studies have supported a genetic component in the aetiology of SZ. However, no gene has been identified, possibly because of the phenotypic complexity of psychosis. Several studies have suggested that combined action of many genes and environmental factors could play a role in the manifestation of symptoms. New strategies in phenotype definition have been suggested as useful tools for the detection of genes of minor effect. Interleukin-1ß (IL-1 ß) is a candidate gene for schizophrenia as it plays an important role in: i) the development of the CNS and ii) neurodegeneration. The aim of the present study was to analyze a genetic polymorphism of the promoter region of the IL-1ß gene in SZ patients according to: i) categorical diagnosis, ii)dimensional approach to the phenotype, in a family based association study. The sample con-

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sisted of 89 quadruplets (parents and discordant sibs for SZ and SZ-related disorders (DSM-IV)). For the dimensional approach, lifetime ratings of symptoms from the CASH were used to define the presence or absence of the six core dimensions of the psychotic illness: reality-distortion, disorganization, negative symptoms, mania, depression and catatonia (Van Os et al., 1996, Peralta et al., 2001). TDT was used to search for linkage of the alleles to psychiatric phenotype. A trend for biased transmission of allele 2 from heterozygous parents to the affected offspring, categorically defined, was found (P ¼ 0.07). This tendency was not observed in the healthy offspring. Using a multidimensional symptom approach to the diagnosis, the association was confirmed in SZ patients showing the depressive symptom dimension (P ¼ 0.02), suggesting the importance of the IL1ß gene in this symptom dimension of psychosis. Acknowledgements: This study was supported by the Vada and Stanley Foundation. P316 IMPAIRED NIACIN-INDUCED VASODILATATION AS A POSSIBLE PHENOTYPIC MARKER IN SCHIZOPHRENIA Ross B,1 MacLean R,2 and Glen, I1 1 Highland Psychiatric Research Foundation, Inverness, Scotland, UK 2 New Craigs Hospital, Inverness, Scotland, UK Niacin (nicotinic acid) induces vasodilatation in healthy individuals. This response is mediated by a signaling cascade involving the activation of phospholipase A2 and cyclooxygenase, and at least two cell types. Assessment of niacininduced vasodilatation is accomplished using the niacin derivative, methyl nicotinate, which produces localized increases in blood flow when applied topically. The response can be assessed either visually or by laser Doppler flowmetry. We and others have conducted a series of investigations showing that niacin response is absent or impaired in many, though not all, patients with schizophrenia. This effect is evident in medicated and un-medicated chronically ill patients and in first episode cases. Using both data collected from human subject studies and animal models, we have shown that impaired niacin-induced vasodilatation is unlikely to be due to confounding factors such caffeine and nicotine consumption or diet. Niacin response has also been studies in other mental illnesses. In bipolar disorder, response is largely normal, although severely ill patients show a mild deficit. Overall, subject with bipolar disorder are clearly differentiable from those with schizophrenia using this procedure. Interestingly, in unipolar depression although the extent of vasodilatation is normal, the time taken for the reaction to occur in lengthened. Thus, niacin response can differentiate schizophrenia from other major mental illness, as well as providing the basis for identifying subgroups of patients with schizophrenia with a normal or impaired reaction. We have utilized this method to

detect otherwise obscured biochemical abnormalities and suggest that niacin response may be useful as a phenotypic marker in molecular genetic studies. P317 QUANTITATION OF X-Y HOMOLOGOUS GENES IN PATIENTS WITH SCHIZOPHRENIA Ross NLJ,1 Mavrogiannis LA,2 Sargent CA,3 Knight SJL,2 Wadekar R,1 DeLisi LE,4 and Crow TJ1 1 University of Oxford, Department of Psychiatry, Warneford Hospital, Headington, Oxford, UK 2 Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Headington, Oxford, UK 3 Human Molecular Genetics Group, Department of Pathology, University of Cambridge, UK 4 New York University School of Medicine, Mill Hauser Laboratories-422, New York The genetic basis of schizophrenia is obscure. In an XX male patient with schizophrenia we previously showed that the X; Y translocation breakpoint was in the pseudoautosomal region 1 (PAR1)1. The segment of PAR1 extending proximally from the pseudoautosomal boundary to acetylserotonin Nmethyl transferase (ASMT) distally was triplicated in this patient. To determine whether dosage imbalances of X-Y homologous regions could be associated with schizophrenia, we developed a multiplex semi-quantitative PCR assay. We have included the MIC2 gene as a representative of PAR1 and the SYBL1 gene which maps in PAR2. An X-specific exon of protocadherin XY (PCDHXY), located at Xq21.3, provided an X-specific control. Each of the three loci was co-amplified with the autosomal locus MSw2 that served as an internal dosage control. The method was validated using genomes with sex chromosome aneuploidies and was found sensitive enough to detect a twofold difference in gene copy number. Although the method confirmed the MIC2 triplication in the XX male patient, no gene dosage imbalances were found in a panel of 17 patients with schizophrenia. P318 NUR-RELATED RECEPTOR 1 AND SCHIZOPHRENIA Ruano D,1,2 Macedo A,3 Dourado A,3 Soares M,3 Valente J,3 Azevedo MH,3 Coelho I,3 Goodman AB,4 and Palha JA1,2 1 Institute for Molecular and Cell Biology, Porto, Portugal 2 Health Sciences School, University of Minho, Braga, Portugal 3 Instituto de Psicologia Me´dica, Faculdade de Medicina, Universidade de Coimbra, Portugal 4 Department of Psychiatry at Massachusetts Mental Health Center, Harvard Medical School, Boston, Massachusetts The human Nur-related receptor 1 (Nurr1) is an orphan nuclear receptor that can be constitutively active as a transcription factor and for which no natural ligand has yet been identified. Nurr 1 heterodimerizes with the retinoic acid

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receptor, RXR, and serves as a partner to facilitate vitamin A (retinoid)-regulated nuclear transcription. In the presence of proper ligands, particularly 9-cis retinoic acid, a final product of the retinoid cascade, the Nurr-1/RXR heterodimer regulates nuclear transcription of target genes. Nurr 1 is a single gene, 8.3 Kb long, consisting of eight exons that maps to chromosome 2q22-23. Several groups have reported evidence supporting a role for Nurr1 in schizophrenia: 1) Nurr1 is expressed predominantly in the dopaminergic neurons in the brain. Studies with Nurr1-null mutant mice demonstrated that Nurr1 is essential for final differentiation of ventral mesencephalic dopaminergic neurons.2) Linkage studies of schizophrenia have implicated the 2q22-23 region.3) Alterations in retinoid metabolism have been suggested to be important in the etiology of schizophrenia.4) Recently, two different missense mutations in the third exon of the Nurr 1 gene have been identified in schizophrenic patients. In the present study we investigated 165 Portuguese patients (104 men, 62 women) and 77 Portuguese controls, both diagnosed in a life-time basis using the Diagnostic Interview for Genetic Studies and the OPCRIT system. We failed to detect the described mutations in any of the patients or controls. For all of the above reasons it will be worthwhile to continue to search for other mutations in Nurr-1, which may increase vulnerability to schizophrenia.

P319 A PHARMACOLOGICAL MODEL FOR PSYCHOSIS Rujescu D,1 Bender A,1 Keck M,2 Ohl F,2 Ra¨der H,1 and Grunze H1 1 Molecular Neurobiology, Department of Psychiatry, Ludwig-Maximilians-University, Munich, Germany 2 Max Planck Institute of Psychiatry, Munich, Germany Elevated levels of the endogenous NMDA receptor antagonist NAAG have been found in the brain of schizophrenic patients. To mimic this condition, we developed a pharmacological animal model for psychosis in rats treated chronically with very low doses of the NMDA receptor antagonist MK 801. We hypothesized that NMDA-receptor expressing interneurons might be involved in the pathogenesis of psychosis since they perform inhibitory control over excitatory glutamatergic neurons. Electrophysiological studies in the hippocampus showed an altered recurrent inhibition, immunohistochemical studies showed a selective decrease in the number of interneurons which are involved in these circuits, NMDA receptor expression studies revealed a differential expression of subunits and splice variants, and behavioral studies showed no neurological signs or gross disturbances in emotionality but cognitive dysfunction which is compatible with psychosis. In summary, this model can be valuable in the investigation of several aspects of psychosis and in the identification of candidate genes in schizophrenia.

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P320 PHARMACOGENOMIC STUDY OF RISPERIDONE IN SCHIZOPHRENIA: POLYMORPHISM OF DOPAMINE D2, D3, AND SEROTONIN 5HT2A RECEPTORS Rybakowski JK,1 Leszczyn´ska-Rodziewicz A,1 Czerski PM,2 Borkowska A,3 Dmitrzak M,2 and Hauser J1,2 1 Department of Adult Psychiatry, University of Medical Sciences, Poznan, Poland 2 Laboratory of Psychiatric Genetics, University of Medical Sciences, Poznan, Poland 3 Department of Psychiatry, University Medical School, Bydgoszcz, Poland The pharmacogenomic studies performed on atypical neuroleptics (clozapine and olanzapine) suggest a possibility of an association between response to treatment and polymorphisms of dopaminergic and/or serotoninergic system genes. There were no such studies performed so far on risperidone. Here, we present data on 74 schizophrenic patients treated with risperidone, for at least 8 weeks in the Department of Adult Psychiatry in Poznan, with dose range of the drug from 2–6mg/day. Sixty patients responded favorably to treatment, and 14 were poor responders. We did not find an association between the efficacy of risperidone and the -141C ins/del polymorphism of DRD2 gene (P ¼ 0.757 for genotypes, P ¼ 0.773 for alleles) as well as for Ser9Gly DRD3 gene polymorphism (P ¼ 0.254 for genotypes and P ¼ 0.172 for alleles) and 5HT2A receptor gene T102C polymorphism (P ¼ 0.747 for genotypes and P ¼ 1 for alleles). However, a trend was noticed toward an association of Ser/Ser genotype of DRD3 gene and good response to risperidone (51.1% of good responders with Ser/Ser genotype versus 34.5% of poor responders). P321 IDENTIFICATION OF DIFFERENT GENE EXPRESSION PATTERNS IN CLOZAPINE RESPONSIVE AND CLOZAPINE RESISTANT SCHIZOPHRENIC PATIENTS BY DIFFERENTIAL DISPLAY Salehi M,1 Salehi R,1 and MH. Goyns2 1 Department of Genetics and Molecular Biology, Isfahan University Medical School, Iran 2 School of Sciences, Sunderland University, England The response of the schizophrenic patients to Clozapine is very different. While some patients demonstrate significant improvement and are considered as good responders, some others demonstrate mild improvement and are considered as bad responders. The aim of this study was to find genetic markers that can predict efficacy of the treatment with Clozapine in schizophrenic patients. The patients chosen for this study were a subset of the patients participating in a prospective two years study to evaluate the effect of Clozapine in schizophrenic patients. We have chosen 6 patients, 3 of whom have experienced good response to Clozapine and 3

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who have not responded so good. We then have compared the pattern of gene expression in the blood samples of these two groups, by the polymerize chain reaction (PCR) based technique of differential display. By using a combination of 26 primer pairs it was possible for us to survey the expression pattern of about 2000 different genes that are expressed in the leukocytes of the patients. Although the majority of these genes appeared to have the same expression between the two groups but there were at least 21 genes that demonstrated differential expression pattern between the two group. Our results clearly demonstrated that there are genes that their pattern of expression is different in the two schizophrenic groups, good responders compared to bad responder to Clozapine. This pattern of gene expression can be used in predicting efficacy of the Clozapine treatment in schizophrenic patients. P322 AN INTRAGENIC MARKER OF CENTRAL NICOTINIC A7 RECEPTOR CORRELATES WITH PSYCHOPATHOLOGY OF SCHIZOPHRENIA Sanak M Department of Biochemistry, Institute of Pharmacology Polish Academy of Science, Cracow, Poland Abnormal sensory inhibition has been proposed as a indicator of schizophrenia. Sensory filtering, measured by paired auditory stimuli, is abnormal in patients and their relatives. A similar effect has been reproduced in animal model of mice with reduced density of central nicotinic a 7 receptor. However, in psychiatric practice, rating scales have established value in assessment and monitoring of the disease. We looked for a genetic polymorphism of the nicotinic a 7 subunit gene (ACRA7) in patients with schizophrenia and its correlation to schizophrenia scales (KOSS, PANSS) and to auditory evoked potentials (AEP). Studied group consisted of 286 Polish patients with schizophrenia diagnosed on ICD10 criteria (142 females; age 37.2  13 y., age of onset of disease 24.8  7.5 y.). By mutation screening we found a single nucleotide polymorphism in ACRA7 gene, a C1044T conservative transition of the 348 proline codon. Genotyping results were compared to the population sample (n ¼ 170, 80 females). In patients during early clinical improvement phase (n ¼ 38) auditory evoked potentials (P50) were measured and compared to 18 relatives of patients and 26 controls. Heterozygosity for 1044T allele of ACRA7 was found in 26 schizophrenia patients and 15 controls, thus allelic frequency was the same in both groups (4.4% vs.4.5%). Within the subjects tested for AEP, 5 patients and 5 controls were heterozygous. Patients heterozygous for 1044T allele, at the presentation of the disease were scored as more agitated (2.69 vs.1.93; P < 0.05) but having less blunted affect (2.65 vs. 3.43; P < 0.05). This findings were replicated with different scales, and were consistent in correlated items. Response to classical neuroleptic treatment was better in

ACRA7 heterozygotes, as scored by a KOSS (14.1  7.7 vs. 10.3  7.2, P < 0.05) or a simple 4 level scale (2.0  0.7 vs. 1.7  0.5; P < 0.05). No differences in P50 AEP were detected in relation to the ACRA7 polymorphism, however AEP were better gated in controls than in patients and their relatives (70% vs. 13%; P ¼ 0.07). A conservative polymorphism of ACRA7 may by a marker for psychopathology symptoms and response to treatment in schizophrenia, however, the study had no power to detect its association with AEP. P323 ASSOCIATION STUDIES OF POLYMORPHISMS AT SIX CANDIDATE GENES IN SCHIZOPHRENIC PATIENTS WITH AUDITORY HALLUCINATIONS AND THE ANTIPSYCHOTIC RESPONSE Sanjuan J,1 Pajuelo JC,2 Gonzalez JC,1 Toirac I,2 Can˜ete C,1 Molto´ MD,2 Echanove MJ.,1 de Frutos R,2 Leal C,1 and Na´jera C2 1 Unidad de Psiquiatrı´a, Facultad de Medicina, Universitat de Valencia, Spain 2 Departamento de Gene´tica, Facultad de Biologı´a, Universitat de Valencia, Spain To address the genetic studies in schizophrenia, one strategy has been dissecting the phenotypes in clinical subtypes. Auditory hallucinations show several advantages in this way. Disturbances in dopaminergic or serotoninergic systems have long been implicated in the pathogenesis of schizophrenia, principally because of the role as sites for antipsychotic drug action. On the other hand, several studies have found significant associations between polymorphic variants of the CCK receptors and auditory hallucinations. We have assessed the association between several polymorphims of DRD2, DRD3 DRD4, HT2A, 5HTT, and CCK-AR with auditory hallucinations and with the antipsychotic response in 104 patiens. Most of them fulfilled criteria for schizophrenia and the rest for schizoafective disorder according to DSM-IV diagnosis. All patients have been for at least one year with antipsychotic treatment. No association between all of these polymorphisms and auditory hallucinations was observed. However the group of patients with null response to the antipsychotic correlated with the CCK-AR polymorphim (P ¼ 0.001). P324 COMMON GENETIC BASIS OF FUNCTIONAL PSYCHOSES Scharfetter C,1 Bridler R,1 Nu¨rnberg P,3 Weisbrod M,2 and Stassen HH1 1 Psychiatric University Hospital, Zurich, Switzerland 2 Psychiatric University Hospital, Heidelberg, Germany 3 Max-Delbruck-Center, Berlin, Germany The functional psychoses ‘schizophrenia’, ‘schizoaffective disorder’, and ‘bipolar illness’ are complex diseases with

Abstracts

a strong genetic component that does not follow simple Mendelian or near Mendelian modes of inheritance. There is considerable overlap between the clinical syndromes of these diagnostic entities, and the lifetime prevalences of schizophrenia and bipolar illness are each 1% across ethnically diverse populations. Our recent genome scan of 77 nuclear families ascertained through index cases with a diagnosis of schizophrenia revealed 12 vulnerability loci on chromosomes 1, 4, 5, 6, 13, 14, 18 and 20 which were reproducible across Afro-American and NonAfro-American families, thus constituting an ethnicity-independent vulnerability model. In our current study of 87 multiplex nuclear families (5 families with index diagnosis MD, 29 with index diagnosis BP, 19 with index diagnosis SA, 34 with index diagnosis SZ; 477 genotyped subjects) we investigate the extent to which the clinical syndromes underlying functional psychoses -and differently expressed in the diagnostic entities ‘schizophrenia’, ‘schizoaffective disorder’ and ‘bipolar illness’- share a common genetic basis. Following a genotypeto-phenotype strategy, we search for oligogenic marker configurations (>12 loci) that display significant deviations of genetic similarity from the expected values in families with affected and unaffected sib pairs. The search is done under the constraint of reproducibility in the diagnostic entities. Once a marker configuration has been detected, the multidimensional structures on the genotype level are correlated with the characteristics of the disorder on the phenotype level using quantitative, syndrome-oriented measures of psychopathology. Supported in part by a grant of the Swiss National Science Foundation (SNF 32-61578.00), part of the data is from the NIMH Human Genetics Initiative.

P325 ANHEDONIA IN SCHIZOPHRENIA: A DISTINCT FAMILIAL SUBTYPE? Schu¨rhoff F,1,2 Szo¨ke A,1,2 Bellivier F,1,2 Rouillon F,1,2 and Leboyer M1,2 1 Service de Psychiatrie Adulte, Hoˆpital Albert Chenevier et Henri Mondor (AP-HP), Cre´teil, France 2 Unite´ INSERM U 513, ‘Neurobiologie et Psychiatrie’, Hoˆpital Henri Mondor, Cre´teil, France Failures to replicate results in psychiatric genetics might be due to our inability to define the heritable phenotype. Instead of relying entirely on classical nosographical approaches, the use of a candidate symptom approach to identify more homogeneous forms of diseases among affected subjects and sub-clinical traits among first-degree relatives may increase genetic validity. Anhedonia may be a marker for subjects at risk of schizophrenia or schizophrenia spectrum disorders. We compared the familiality of anhedonia characterized by a high level of physical anhedonia (score above 23) in a sample of schizophrenic probands (N ¼ 80) and their relatives (N ¼ 78), with that in bipolar patients (N ¼ 109), their re-

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latives (N ¼ 33) and normal controls (N ¼ 94). We identified a subform of schizophrenia characterized by highly anhedonic schizophrenic probands with a three-fold higher familal risk of schizophrenia and schizophrenic spectrum disorders. We also found that their first-degree relatives had a high level of anhedonia. An intrafamilial correlation analysis confirmed the familial nature of anhedonia. Our data suggest that anhedonia is a candidate symptom for schizophrenia. Refining phenotype definition by studying subgroups of anhedonic and non anhedonic probands with relevant candidate genes might be fruitful.

P326 A LARGE SAMPLE WITH SIB-PAIR FAMILIES WITH SCHIZOPHRENIA FROM INDONESIA FOR LINKAGE STUDIES IDENTITY BY DESCENT Irmansyah,1 Schwab SG,2 Heriani,1 Nasrun MW,1 Amir N,1 Widyawati I,1 Wibisono S,1 Handoko HY,3 Hallmayer J,4 Hanses C,2 Sewekow C,2 Jablensky A5 and Wildenauer DB2 1 Department of Psychiatry, University of Indonesia, Jakarta, Indonesia 2 Department of Psychiatry, University of Bonn, Germany 3 Queensland Institute of Medical Research, Brisbane, Australia 4 Department of Psychiatry, Stanford University, Palo Alto 5 University of Western Australia, Perth, Australia In collaboration with 25 Mental State Hospitals (total number in Indonesia: 31) located in Java, Sumatra, Kalimantan, Bali, Sulawesi, we recruited more than 120 families having at least two affected siblings with schizophrenia or schizoaffective disorder (mainly schizophrenic). Both parents were available for interview in about 70% of the families. The remaining families had at least one parent and several unaffected siblings available. Blood for DNA isolation was drawn from all individuals. Thus, the sample is ideal for sib-pair analysis strictly identity by descent. All relevant data and the Diagnostic Interview for Psychoses (DIP), a semi-structured interview, were used for clinical characterization. In addition, we used the Personal Psychiatric History Schedule (PPHS), the Family Interview for Genetic Studies (FIGS) and OPCRIT. Diagnosis according to DSM III-R and ICD-10 was made by experienced clinicians. Diagnostic instruments had been translated into Bahasa Indonesian, randomly selected records were back-translated. Previously we had analyzed regions with reported evidence for linkage on chromosome 8p, 10p, and 13q in a subset of the families. We have added the additional recruited families and have extended genotyping to candidate regions on chromosome 1p, 4q, 5q, 6, 18, 15q, and 22q. These regions are currently being evaluated using sib-pair analysis. (supported by a grant from the German Federal Ministry for economic co-operation and development).

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P327 INVESTIGATION OF CHROMOSOMAL REGIONS WITH REPORTED LINKAGE TO SCHIZOPHRENIA IN A SAMPLE WITH 57 AFFECTED SIB-PAIR FAMILIES FROM CROATIA Schwab SG,1 Ljubimir V,2 Hrabak-Zerjavic V,3 Folnegovic-Smalc V,2 Folnegovic Z,4 Ivezic S,2 Hanses C,1 Markovic D,5 Ott J,5 Knowles JA,6 Erlenmeier-Kimling N,6 and Wildenauer DB1 1 Department of Psychiatry, University of Bonn, Germany 2 Department of Psychiatry, Psychiatric Hospital Vrapce, University of Zagreb, Croatia 3 Department of Epidemiology and Informatics, University of Zagreb, Croatia 4 Croatian National Institute of Public Health, Zagreb, Croatia 5 Rockefeller University, New York 6 Department of Psychiatry, Columbia University, New York Families having at least two siblings with schizophrenia or schizoaffective disorder (mainly schizophrenic) according to RDC were identified through the Croatian National Psychosis Register. Initially (1988), the search was for large pedigrees. As the incidence of schizophrenia had been reported in epidemiological studies to be higher in Croatia’s Istrian peninsula than the usual rate of about 1%, it seemed possible that there might be more large pedigrees than usually found elsewhere. However, later epidemiological work did not show an increase of schizophrenia in Istria, and the study therefore followed the field in adopting the affected sib-pair method. Most families in the sample came from areas surrounding Zagreb. Individuals were interviewed with SADSL, blood was drawn, and diagnosis was made by experienced clinicians (i.e. the interviewer in Croatia and one or two expert diagnosticians in New York). Fifty seven families met the criteria. Among them, 9 families had both parents available, 26 were with one parent and additional unaffected siblings, 17 without parents, but with unaffected siblings, and 4 families without parents and without additional unaffected siblings. The sample comprised 280 individuals including 137 with schizophrenia/schizoaffective disorder (2.4/family). Genotyping with microsatellite markers has been performed for candidate regions on chromosomes 1p, 4q, 5q, 6, 8p, 10p, 13q, 18, 15q, and 22q. These regions are currently evaluated using parametric and model-free methods.

P328 IMMUNOGENETIC INVESTIGATIONS SUPPORTING THE TH2-HYPOTHESIS OF SCHIZOPHRENIA Schwarz MJ, Riedel M, Kroenig M, Minov C, Strassnig M, Sikorski C, Mo¨ller HJ, Mu¨ller N, and Ackenheil M Psychiatric Hospital, University of Munich, Germany

In recent years, evidence has accumulated supporting the involvement of an immune process in the pathophysiology of the disease, characterized by a predominance of the Th2-like humoral immune response and a reduction of the Th1-like cellular immune response (Schwarz et al., 2001). Genes coding for cytokines that regulate the balance between Th1 and Th2 immune response are located on the short arm of chromosome 5. The existence of a susceptibility locus within this cytokine gene cluster was repeatedly reported (e.g. Schwab et al., 2000). Thus we investigated the following single nucleotide polymorphisms (SNP) of genes, located in this region as candidate genes for schizophrenia in 150 unrelated schizophrenic patients and 150 healthy controls: IL-4 C589T SNP (promotor region), IL-12 p40 G1188T SNP (untranslated region), IL-13 A4254G SNP (coding region), and CD14 C159T SNP (promotor region). There was no difference between the two study groups in genotype distribution regarding the IL-4 and IL-12 SNPs; homozygosity for the polymorphic A allele of the IL-13 gene polymorphism was more frequent in the schizophrenic patients than in the healthy controls (Chi* ¼ 9.51; df ¼ 2; P ¼.009). The most intriguing result was found in the CD14 gene, as homozygosity for the T allele was present in 51% of the healthy controls, but only in 26% of the patients (Chi* ¼ 25.15; df ¼ 2; P OR) for these variants. It is also possible that the original associations reflect associations with sub-phenotypes of schizophrenia, or other phenotypical confounders that lead to differential ascertainment across datasets. We are currently using our large ethnically homogeneous samples to explore these possibilities.

P331 DOPAMINE D3 RECEPTOR AND IMPROVEMENT IN POSITIVE SYMPTOMS OF SCHIZOPHRENIA Staddon S,1 Arranz MJ,1 Mata I,2 Munro J,1 Osborne S,1 Collier D,1 and Kerwin R1 1 Department of Clinical Neuropharmacology, Institute of Psychiatry, London, UK 2 Fundacion Argibide, Pamplona, Navarra, Spain The dopamine hypothesis of schizophrenia suggests that enhanced dopaminergic activity is responsible for the pathophysiology of the disease, and this activity is responsible for generation of positive symptoms such as delusions and hallucinations. Neuroleptic drugs, which block dopamine transmission by binding to its receptors, relieve psychotic symptoms. The dopaminergic 3 (D3) receptor is expressed in brain limbic areas related to the pathophysiology of schizophrenia and is a target for antipyschotic drgs. Several groups have reported an altered frequency of a polymorphism in the coding region of the D3 receptor gene (DRD3), Ser9Gly, among schizophrenic patients. Polymorphisms in the DRD3 may influence general response and/or the improvement in symptoms in treated patients. We have investigated the Ser9Gly polymorphism and two polymorphisms in the promoter region of the DRD3, -205-A/G and Ala38Thr, in a sample of 111 patients of Spanish origin treated with olanzapine. Clinical response was assessed using GAS and PANSS scales after at least three months of treatment. Preliminary results show an association between the rarer variants of the Ser9Gly and -205-A/G polymorphisms and improvement in positive symptoms (P ¼ 0001).

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P332 THE ASSOCIATION OF AGGRESSIVE BEHAVIOR IN SCHIZOPHRENIA WITH THE LOW ENZYME ACTIVITY COMT POLYMORPHISM Strous RD,1 Nolan K,2 Lapidus R,1 Saito T,3 Kotler M,1 and Lachman HM3 1 Beer Yaakov Mental Health Center, Sackler School of Medicine, Tel Aviv University, Israel 2 Nathan S. Kline Institute for Psychiatric Research, Orangeburg, New York 3 Department of Psychiatry and Behavioral Sciences Albert Einstein College of Medicine, Bronx, New York Increased violent behavior in schizophrenic patients has been associated with a polymorphism at codon 158 of the catechol O-methyltransferase (COMT) gene that encodes a low enzyme activity variant. While this finding has been replicated at least by one group, others have demonstrated discordant findings which may be attributed to different diagnostic criteria used to assess violent behavior and, considering the complexity of aggressive behavior, may be due to both either type I and or type II statistical errors. Consequently, additional studies with a much larger cohort are required. One hundred and twenty two patients with schizophrenia were assessed for violent behavior using the Lifetime History of Aggression (LHA) scale, an 11-item questionnaire that is subdivided into Aggression, Self Directed Aggression, and Consequences/Antisocial Behavior subscales. DNA was genotyped for the COMT 158 polymorphism. Similar to our previously reported findings, a statistically significant association was found between violent behavior in schizophrenia and the COMT 158 polymorphism. Mean LHA scores were higher in subjects homozygous for the low enzyme activity COMT variant, 158Met. Analysis of the major LHA subscales revealed that the association with 158Met was due to high scores on the Aggression, and Self Directed Aggression subscales, but not the Consequences/Antisocial Behavior subscale. Our findings further suggest the likelihood that COMT is a modifying gene playing a role in determining interindividual variability in the tendency for outward and self directed violent behavior found in a subgroup of schizophrenic patients.

P333 FAMILY-BASED ASSOCIATION STUDY OF THE NOTCH 4 GENE IN SCHIZOPHRENIA USING JAPANESE AND CHINESE FAMILIES Takahashi S,1,2 Cui J-H,3 Kojima T,2 Han Y-H,3 Yu S-Y,2 Tanabe E,2 Yara K,2 Matsuura M,2 Matsushima E,5 Nakayama J,4 Arinami T,4 Shen Y-C,3 Faraone SV,1 and Tsuang MT1 1 Massachusetts Mental Health Center, Department of Psychiatry, Harvard Medical School, Massachusetts 2 Department of Neuropsychiatry, Nihon University, School of Medicine, Tokyo, Japan

3

Institute of Mental Health, Beijing Medical University, Beijing, China 4 Department of Medical Genetics, Institute of Basic Medical Sciences, University of Tsukuba, Japan 5 Department of Neuropsychiatry, Faculty of Medicine, Tokyo Medical and Dental University, Japan A family-based association study of chromosome 6p21.3 in a British sample showed the NOTCH4 gene was associated with schizophrenia. However, all six replication studies (two European samples, two Japanese samples, one American sample and one Chinese sample) have failed to confirm the association between NOTCH4 and schizophrenia. In this study, we performed a family-based association study of NOTCH4 gene in schizophrenia to replicate the prior studies. We performed a TDT (transmission/disequilibrium test) in 123 trios (16 Japanese and 107 Chinese trios). In addition to the original study’s polymorphisms, we examined four new SNPs (single nucleotide polymorphisms) (SNP#1, #2, #4 and #5) around the SNP1 of the original study (SNP#3 of our study). We genotyped all samples for the SNP#1–5 and the (CTG)n of the original study. There were no significant associations between the NOTCH4 gene and schizophrenia for all polymorphisms. However, we did find that SNP#1 may be associated with early onset schizophrenia; and SNP#3 (SNP1 of the original study) may be associated with negative type schizophrenia. In conclusion, NOTCH4 is not a significant susceptibility gene for schizophrenia, when clinical heterogeneity is ignored. However, the NOTCH4 gene may be associated with early onset schizophrenia or negative type schizophrenia, but these findings should be interpreted cautiously. P334 TUMOR NECROSIS FACTOR ALPHA GENE PROMOTER POLYMORPHISM AND GENETIC SUSCEPTIBILITY TO SCHIZOPHRENIA Tan EC,1 Chong SA,2 Tan CH,3,4 Teo YY,1 KT Peng,1 and Mahendran R2 1 Defence Medical Research Institute, Defence Science and Technology Agency 2 Woodbridge Hospital/Institute of Mental Health 3 Department of Pharmacology, National University of Singapore, Singapore 4 Department of Psychological Medicine, National University Hospital, Singapore Significant increase in the level of certain cytokines have been reported for patients with schizophrenia and there is evidence that cytokines may modulate the course of disease progression and also influence the response to treatment. In particular, alterations in the plasma concentration of interleukins 1 and 6 and tumor necrosis factor alpha have been reported. For TNFalpha on chromosome 6 within the MHC class III region, there is a promoter polymorphism which is associated with susceptibility to or severity of several

Abstracts

immune related disorders. We genotyped three hundred and two cases who are patients from a mental hospital and one hundred and fifty-two healthy controls for a promoter polymorphism in the TNF gene. All the subjects are second or third generation Chinese and resident in Singapore. Genotype distribution for both patient and control groups conformed to Hardy-Weinberg equilibrium. There was significant difference in the distribution of the three genotypes between the patient and control groups. The association remained significant even after the correction for age and gender in subsequent analysis (P ¼ 0.016). There was also highly significant difference in the allele frequencies between the two groups (P ¼ 0.001). Our data suggest the presence of a susceptibility locus for schizophrenia in this region of chromosome 6 and that immune dysfunction involving TNF could have a role in the pathogenesis of schizophrenia. P335 ASSOCIATION STUDIES OF THE METABOTROPIC GLUTAMATE RECEPTOR GENES, GRM3 AND GRM4, WITH SCHIZOPHRENIA Tani A,1 Fujii Y,1 Shibata H,1 Kikuta R,1 Makino C,1 Hirata N,1 Shibata A,1 Ninomiya T,2 Tashiro N,3 and Fukumaki Y1 1 Division of Disease Genes, Research Center for Genetic Information, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan 2 Fukuoka Prefectural Hospital Psychiatric Center, Dazaifu, Japan 3 Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan Glutamatergic dysfunction is one of the major hypotheses of schizophrenia pathology. We have been conducting systematic studies on the association between glutamate receptors and schizophrenia. We now report positive associations of haplotypes of the metabotropic glutamate receptor genes, GRM3 (7q21.1-21.2) and GRM4 (6p21.3), with schizophrenia. We genotyped Japanese schizophrenics (n ¼ 100) and controls (n ¼ 100) for six nucleotide polymorphisms (SNPs) in GRM3 and four SNPs in GRM4 at intervals of approximately 50 kb. A case-control association study of GRM3 revealed a significant difference in allele frequencies of SNP in intron 3 of GRM3 between cases and controls (P ¼ 0.011). We also observed significant differences (P ¼ 8.30  104) in haplotype frequencies constructed from the three SNPs of GRM3. A case-control association study of GRM4 revealed significant differences in haplotype frequencies constructed from the SNPs in introns 1 and 2 of GRM4, although no significant difference in allelic or genotype frequencies of GRM4 were detected between cases and controls (P ¼ 0.0085). These results suggest that susceptibility loci for schizophrenia are situated within or very close to the GRM3 and GRM4 regions in the Japanese patients.

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P336 CHARACTERISATION OF A MICRODELETION IN Xp11.23 ASSOCIATED WITH X-LINKED RETINITIS PIGMENTOSA (RP2) AND PSYCHOSIS IN A SMALL FAMILY Thiselton DL,1,§ Brandau O,2,# Meindl A,2 Riley BP,3 Kendler KS,3 Van Maldergem L,4 and Hardcastle AJ1 1 Department of Molecular Genetics, Institute of Ophthalmology, University College London, UK 2 Abteilung fu¨r Padiatrische Genet der LMU, Munich, Germany 3 Virginia Institute of Psychiatric and Behavioural Genetics, Virginia Commonwealth University, Richmond, Virginia 4 Dept of Medical Genetics, Institute of Pathology and Genetics, Gerpinnes, Belgium Current address: §Virginia Institute of Psychiatric and Behavioural Genetics, VCU, Richmond, Virginia #Max Planck Institute of Biochemistry, Department of Molecular Medicine, Martinsried/Munich, Germany As part of a targetted STS-deletion screen of XLRP families to pinpoint the genomic critical region encompassing the RP2 gene, a family was identified in which 2 brothers, both affected with RP, shared a common deletion in Xp11.23. PCR analysis using a dense array of STS markers positioned onto a comprehensive physical map established that the deletion spanned 700 kb between markers DXS1408 and stsG9154. In addition to RP, the brothers share a history of psychosis, the more severely affected having a DSM-IV diagnosis of paranoid schizophrenia. By analysis of genomic sequence data, we have generated novel STSs to more precisely delineate the deletion end-points, and used both RT-PCR and bioinformatic tools to functionally annotate the deleted interval and identify genes and pseudogenes located within it. Long-range PCR, cloning and sequencing is now underway to determine the exact deletion breakpoint. Several reports have provided evidence of a schizophrenia susceptibility locus on Xp11. The family described here may offer cytogenetic support for such a notion and assist in the search for associated genetic variants. Studies are in progress to more definitively ascertain the psychiatric phenotype in this family, to develop a characterized SNP map of the interval, and to examine the affected genes for mutations or sequence variants which may be associated with a similar disorder in relevant patient cohorts. P337 GENETIC ANALYSIS OF DISC1, A CANDIDATE SUSCEPTIBILITY GENE FOR MAJOR PSYCHIATRIC ILLNESS Thomson PA,1 Millar JK,1 Taylor MS,2 Devon RS,1 Christie S,1 Muir WJ,1,3 Blackwood DHR,1,3 and Porteous DJ1 1 Medical Genetics Section, Department of Medical Sciences, The University of Edinburgh, UK 2 MRC Human Genetics Unit, Edinburgh, UK 3 Department of Psychiatry, Royal Edinburgh Hospital, UK

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In a large Scottish family, a balanced translocation t(1: 11) (q42; q14) co-segregates with major psychiatric illness, with a maximum LOD score of 7.1. The translocation directly disrupts two novel genes on chromosome 1: DISC1, a large alternatively spliced gene of approximately 414 kb containing 13 exons, and an antisense gene DISC2. A thorough search for functional sequence variants in non-translocation families showing linkage to the region is justified. We are using a combined approach of cDNA library screening to identify splice variants, and investigation of haplotype sharing in affected families to identify regions for further analysis. cDNA library screening and RT-PCR between known exons and ESTs in the public databases has identified additional functional intronic sequences. This has resulted in the identification of two alternative 30 untranslated regions in intron 9 and alternative polyadenylation signals. These additional sequences will be included in the mutation detection screen and polymorphisms tested for association with psychiatric illness in unrelated individuals. Analysis of affected families with a combination of microsatellite and SNPs has identified three families showing linkage spanning the original translocation breakpoint; two primarily affected by bipolar affective disorder, the third by schizophrenia. Analysis of affected trios will allow us to assess regions of haplotype sharing in the three families and provide a preliminary linkage disequilibrium map of the DISC1/DISC2 locus. Polymorphisms occurring on the associated haplotypes will be identified and tested in association studies. This targeted approach should ensure complete screening of DISC1/DISC2 regions for linkage with psychiatric illness.

P338 A RIGOROUS TEST OF THE CAG TRINUCLEOTIDE REPEAT EXPANSION HYPOTHESIS OF SCHIZOPHRENIA Tsutsumi T,1 Holmes SE,1 Sawa A,1,3 Callahan C,1 McInnis MG,2 Ross CA,1,2,4 DeLisi L,5 and Margolis RL1,4 1 Division of Neurobiology, Johns Hopkins University of School of Medicine, Baltimore, Maryland 2 Division of Psychiatric Genetics, Johns Hopkins University of School of Medicine, Baltimore, Maryland 3 Department of Neuroscience, Johns Hopkins University of School of Medicine, Baltimore, Maryland 4 Program of Cellular and Molecular Medicine, Johns Hopkins University of School of Medicine, Baltimore, Maryland 5 Department of Psychiatry, New York University, New York We and others have proposed that the genetic risk for schizophrenia and other psychiatric disorders could at least partly stem from expansion of trinucleotide repeats, particularly of the CAG/CTG type. To search for novel CAG/CTG repeat expansions, we examined 100 unrelated probands with fami-

lial schizophrenia using the Repeat Expansion Detection (RED) technique, an assay that detects the presence of CAG/ CTG repeats larger than about 50 triplets in length in genomic DNA.28 subjects with CAG/CTG expansions were detected using the RED assay. Using PCR and genomic Southern blots, we tested each RED positive sample for all known pathogenic and nonpathogenic repeat expansions. The expansion in 20 subjects could be accounted for by the nonpathogenic expansion at the Dir1 locus on 17q21.7 of the 8 remaining subjects had expansions of the CTG repeat in SEF2-1 on 18q21, another expansion with no known consequences. The remaining subject had an expansion of the spinocerebellar ataxia type 8 (SCA8) locus on 13q21; this expansion may cause spinocerebellar ataxia type 8, but also occurs in the normal population. In conclusion, all RED positive cases could be explained by expansion of one of three loci known to undergo CAG/CTG repeat expansion in the normal population. While none of the repeat expansions that we detected were novel, we cannot exclude the possibility that the SEF2-1 repeat, expanded in 7% of our patients vs.3% of the general population, could contribute to the risk for schizophrenia. This analysis also does not address CAG/CTG expansions below the threshold of detection for RED or other types of repeats, several of which have been associated with CNS disease.

P339 GENETIC LOADING ASSOCIATES WITH IMPAIRED VISUAL WORKING MEMORY AMONG HEALTHY SIBLINGS OF SCHIZOPHRENIA PATIENTS Tuulio-Henriksson A, Araja¨rvi R, Partonen T, Schreck M, Haukka J, and Lo¨nnqvist J Department of Mental Health and Alcohol Research, National Public Health Institute, Helsinki, Finland The effect of genetic loading on neurocognitive deficits in relatives of schizophrenia patients has been detected in family and twin studies. In the present study we examined this effect among unaffected siblings of schizophrenia patients in a Finnish isolate with high lifetime risk for schizophrenia. We assessed performance in working memory tests, ability tests and declarative verbal memory and learning tasks in 37 and 72 unaffected siblings from 31 families with one schizophrenia patient and 53 families with two or more patients, respectively. The effect of genetic loading was detected in the test measuring visual working memory, in which the siblings from multiply affected families performed significantly worse than the other group (t ¼ 2.03, df ¼ 82, P ¼ 0.045). Furthermore, their scores in that test were significantly below the age-corrected population mean. The result is in line with previous suggestions that visual working memory may be a strong endophenotypic marker for schizophrenia.

Abstracts

P340 GENOME-WIDE LINKAGE DISEQUILIBRIUM (LD) ANALYSIS OF SCHIZOPHRENIA (SC) IN THE COSTA RICAN POPULATION: PRELIMINARY FINDINGS ON CHROMOSOMES 1, 8, 13, 18 AND 22 Walss-Bass C,1 Escamilla MA,1 Raventos H,2 Montero AP,2 Armas R,3 Dassori A,1 Contreras S,1 Levinson D,4 Benavides E,1 Rodriguez S,1 Pereira R,2 Balderas TG,1 Pereira M,2 Atmella I,2 Medina R,1 Gutierrez L,1 Castro R,2 Hernandez M,2 Garbarz JJ,5 Katz I,6 and Almasy L7 1 Department of Psychiatry, University of Texas Health Science Center at San Antonio, Texas 2 Centro de Investigacion en Biologia Celular y Molecular, Universidad de Costa Rica, Costa Rica 3 Langley Porter Psychiatric Institute, University of California, San Francisco, California 4 Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 5 Department of Mental Health, San Francisco, California 6 San Francisco General Hospital, Univ of California, San Francisco, California 7 Southwest Foundation for Biomedical Research, San Antonio, Texas We report here the results of the first part of a genome-wide LD screen for SC susceptibility genes carried out with SC probands and their parents from the isolated founder population of the Central Valley of Costa Rica. Best estimate diagnosis for SC (DSM IV) was made using information from DIGS, FIGS and medical records. Using LD techniques, we genotyped markers at a 5 cM density on chromosomes 1, 8, 13, 18 and 22, all of which have been previously shown to contain putative loci for SC predisposition in other populations. Alleles from a total of 159 chromosomes from probands and 124 control chromosomes were compared using the CLUMP test of Sham and Curtis and the Terwilliger LD test. Preliminary results show possible LD (p values below 0.05) on Ch 8p (D8S1825 and D8S258), Ch 13q (D13S1263, D13S173, and D13S286), and Ch 18p (D18S63 and D18S54). These results support previous findings of SC susceptibility loci on chromosomes 8, 13 and 18. Further analyses, including haplotype analysis and more densely spaced marker screens in these regions will provide information for a finer localization of putative SC genes in this population. Supported by the American Psychiatric Association’s PMRTP, the ICGEB, and NIH grants K01 MH0145304, R01-MH61884 and R01-MH61884-02S1.

P341 ANALYSIS OF PRODH IN VCFS AND SCHIZOPHRENIA Williams HJ,1 Williams NM,1 Norton N,1 Spurlock G,1 Preece A,1 Jones S,1 Zammit S,1 Murphy KC,2 Owen MJ,1 and O’Donovan MC1

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1

Neuropsychiatric Genetics Unit, Division of Psychological Medicine, University of Wales College of Medicine, Tenovus Building, Cardiff, UK 2 Department of Psychiatry, Royal College of Surgeons, Dublin, Eire

PRODH has been proposed as a susceptibility gene for schizophrenia, primarily because it maps to the VCFS deleted region, but also because mice with a homozygous mutation causing premature termination of translation of PRODH show abnormal sensory gating, a phenotype that some consider to be an intermediate phenotype for schizophrenia. Recently, Liu and colleagues (PNAS 2000; 99 (6): 3717-3722) reported that variation at the PRODH locus increases susceptibility to schizophrenia, particularly to juvenile onset schizophrenia. We have attempted to replicate this in our sample of 51 VCFS samples (including 12 with a DSM IV diagnosis of schizophrenia), a schizophrenia case control sample comprising 677 schizophrenic patients and 679 matched controls, and a subset of our case control sample which consists of Juvenile Onset Psychosis (JOP) patients defined as psychotic symptoms before the age of 18. We tested the three marker ‘risk haplotype’ that was reported to be a risk haplotype for schizophrenia, and also tested the hypothesis that mutations within exon 12 (exon 11 in Liu et al paper) of PRODH are more common in schizophrenics. The ‘risk haplotype’ was not present in any of our VCFS samples and in the large case control and JOP sample it was less common in our schizophrenic subjects. We also did not find excess missense mutations in exon 12 in psychotic VCFS subjects (n ¼ 12) nor in the JOP sample (n ¼ 46). Our samples had 99% power to replicate effects of the magnitude described by Lui and colleagues. We conclude that at least in the UK, either PRODH is not a susceptibility gene for schizophrenia, or if it is, the effect sizes are much smaller that reported by Lui and colleagues.

P342 CANDIDATE GENE SCREENING OF THE VCFS DELETED REGION FOR MUTATIONS ASSOCIATED WITH SCHIZOPHRENIA Williams NM,1 Norton N,1 Preece A,1 Spurlock G,1 Williams HJ,1 Zammit S,1 Murphy KC,2 O’Donovan MC,1 and Owen MJ1 1 Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, Wales, UK 2 Department of Psychiatry, Royal College of Surgeons, Dublin, Eire The df1 murine model of VCFS (del 22q11) displays phenotypic characteristics considered by some to model certain neuro-psychological features of schizophrenia. The df1 deletion spans 22 genes with human orthologs in the 22q11 (ES2, Gscl, Ctp, Vpreb2, Dgcr6, Prodh, ym24d07, Op53c05, Ranbp1, Htf9C, Vo59c07, T10, Arvcf, Comt, TrxR2,

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Wdr14, Tbx1, Gp1bb, Pnutl, TmVCF, Cdc45l, Ufd1l). In light of the association between VCFS and psychosis, and also the neuro-psychological findings in the df1 mice, these 22 genes are positional candidate genes for schizophrenia. We have examined whether variation within any of these genes confers susceptibility to schizophrenia. We screened the exons and flanking intronic sequence of each gene for sequence variation in 14 individuals with DSM-IV. All polymorphisms identified were genotyped using DNA pooling in a sample of 368 schizophrenics and matched controls. Evidence for association has been found for 1 of the df1 genes, a finding that has been confirmed by individual genotyping of the 368 subjects. We are currently examining this finding in our extended sample of more than 700 schizophrenic cases and controls, in family based association samples, and in VCFS subjects with and without psychosis. P343 SCREENING OF NEUREGULIN GENES FOR POLYMORPHISMS ASSOCIATED WITH SCHIZOPHRENIA Williams NM, Preece A, Spurlock G, Norton N, Williams, HJ, Kirov G, Zammit S, Owen MJ, and O’Donovan MC Department of Psychological Medicine, University of Wales College of Medicine, Cardiff, Wales, UK Positive linkage reports have been reported for schizophrenia at chromosomes 8p21-22 and 5q22-31. Neuregulins are a family of structurally related glycoproteins which through interaction with ERBB receptors are essential for neuronal development, inducing the growth and differentiation of epithelial, neuronal, glial, and other types of cells. The neuregulin family consists of 4 genes of which the genes NRG1 and NRG2 are located at 8p22-p11 and 5q23-q33 respectively. We have examined whether variation within the genes NRG1 and NRG2 confer susceptibility to schizophrenia. We screened the available exonic and flanking intronic sequence of each gene for sequence variation in 14 individuals with DSMIV. Further polymorphisms in NRG1 were obtained from patent WO0164877. All polymorphisms were genotyped in a sample of 184 schizophrenics and matched controls. Using this approach, we have been unable to find any evidence for association between the neuregulin polymorphisms and schizophrenia. P344 ASSOCIATIONS BETWEEN TARDIVE DYSKINESIA, ETHNICITY, POLYMORPHISMS FOR THE DOPAMINE D3 RECEPTOR GENE (DRD3), AND OTHER CANDIDATE GENES IN SCHIZOPHRENIA Wonodi I,1 Stine C,2 Mitchell B,2 Buchanan R,1 Lin K,3 and Thaker GK1 1 Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, Maryland

2

Department of Epidemiology, University of Maryland, Baltimore, Maryland 3 Department of Psychiatry, Harbor-UCLA Medical Center, University of California Los Angeles, California One to fifteen year follow-up data in patients with tardive dyskinesia (TD; n ¼ 543; 340 were of European descent, EA, and 203 were African-American, AA), showed a significant time by ethnicity interaction (F (1,539) ¼ 5.23, P ¼ 0.02). Subsequent analyses suggested a significant improvement in TD in EA, reducing from an average score of 0.55 þ 0.02 to 0.44 þ 0.02, but not in AA group (average TD score changed from 0.49 þ 0.03 to 0.47 þ 0.03). These findings were unchanged when age, change in antipsychotic drug dose, and duration of follow-up were covaried. Genetic variability contributes to inter-individual, and cross-ethnic phenotypic variance, due to differential allelic frequencies that determine pharmacokinetic and pharmacodynamic effects of medications. The glycine variant of the dopamine D3 receptor gene (DRD3) has been found to be associated with TD in patients with schizophrenia. Polymorphisms of cytochrome P450 isozymes influence drug metabolism. The gammaaminobutyric acid (GABA) system has been implicated in the pathophysiology of TD. With these issues in mind, we are examining associations between TD, ethnicity, and polymorphisms for drug metabolism (CYP2D6), the DRD3, GABA A receptor subunit gene locus (GABRA5), and other candidate GABA A subunits. So far, we have investigated 220 schizophrenic subjects with and without TD. Preliminary analysis in a subset of these subjects (n ¼ 80) showed a preponderance of glycine allele. However, considering the small sample size this was not statistically significant. Analysis of the larger sample is under way.

P345 LINKAGE STUDIES OF DELTA OPIOID RECEPTOR GENE AND PAIN INSENSITIVITY IN SCHIZOPHRENIA Xu J,1 Leo RJ,1 DiMartino S,1 Qi Li D,1 Riester SM,1 and Pato CN2 1 Department of Psychiatry, SUNY at Buffalo, New York 2 Center for Psychiatry and Molecular Genetics, Upstate Medical University, SUNY at Syracuse, New York Pain insensitivity among individuals with schizophrenia has been described in the psychiatric literature. Yet, this condition is not well recognized, and may lead to misdiagnoses or delayed diagnoses of serious medical conditions contributing to significant morbidity and mortality among schizophrenics. Various studies have suggested that endogenous opioids are involved in the pathogenesis of pain insensitivity; elevated levels of these neuropeptides have been found in some schizophrenic patients. Pain insensitivity has also been described among healthy family members of schizophrenic patients (Hooley & Delgado). Pain insensitivity may con-

Abstracts

stitute a biological marker of underlying liability and genetic risk to psychosis. The present study assessed the linkage of variants of the opioid receptor among schizophrenics and their families. Two allelic variants of the delta otioid receptor gene, distinguished by a single base exchange T to C in codon 307 of the translated region, were detected in humans. The resulting C and T alleles combined to give the three genotypes CC, CTand TT. A previous study reported that there is a high frequency of heterozygotes CT and homozygotes TT in normal populations (11% CC, 36% TT, 68% CT). We have studied delta opioid receptor in 25 schizophrenia trios and found significantly increased CC homozygotes in schizophrenic trios (50% CC, 35%TT, 15%CT). We found that schizophrenia trios are significantly more likely than controls to possess a CC genotype and less likely to possess a CT genotype. An increase in genotype CC in the schizophrenic may be involved in the pathophysiology of pain insensitivity in schizophrenia. The direct relevance of such delta opioid receptor variants to pain or analgesic sensitivity in schizophrenia appears significant and warrants further investigation.

P346 EVIDENCE FOR TRANSMISSION DISTORTION IN SCHIZOPHRENIA ON 11q12.1 AND 16P13.3 Yamada K,1 Iwayama-Shigeno Y,1 Yoshida Y,1 Toyota T,1,2 Itokawa M,1,3 Hattori E,1 Yoshitsugu K,1,2 Shimizu H,4 and Yoshikawa T1 1 Laboratory for Molecular Psychiatry, RIKEN Brain Science Institute, Saitama, Japan 2 Department of Neuropsychiatry, Tokyo Medical and Dental University, Japan 3 Department of Schizophrenia Research, Tokyo Institute of Psychiatry, Japan 4 Hokushin General Hospital, Nagano, Japan To explore the susceptibility regions for schizophrenia in the Japanese population, we performed a genome-wide survey for susceptibility loci in Japanese schizophrenic pedigrees using the pedigree disequilibrium test (PDT) and the extended transmission disequilibrium test (ETDT). We genotyped 464 polymorphic microsatellite markers at an average distance of 9.2 cM throughout the whole genome, and for chromosomes 6, 18 and 22, we further genotyped at a density of 4.6 cM. As an initial screen, we performed PDT in 119 multiplex pedigrees and revealed 14 genomic loci on 9 chromosomes which showed significant association with schizophrenia. The highest P value was obtained on 11q12.1 (D11S987, P ¼ 0.0013), followed by 15q22.31 (D15S153, P ¼ 0.0018) and 9p21.3 (D9S171, P ¼ 0.0084). Although evidence for linkage has been repeatedly reported for chromosomes 6, 18 and 22, we failed to detect transmission distortion in these chromosomes. To confirm these results, a

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follow-up analysis was performed using ETDT and 80 independent complete trios, which consisted of members of the multiplex pedigrees and newly recruited families. We found significant evidence for transmission distortion with the markers D11S987 on 11q12.1 (P < 0.0001) and D16S423 on 16p13.3 (P ¼ 0.002). Our results provide evidence suggesting that 11q12.1 and 16p13.3 may harbor susceptibility genes for schizophrenia in the Japanese population. We are now narrowing down the region by using more densely located markers.

P347 MULTIVARIATE ADAPTIVE REGRESSION SPLINE (MARS) ANALYSIS OF SCHIZOPHRENIA GENOTYPES York TP,1,3 Sullivan P,2,3 Webb BT,1,3 Kendler KS,1,2,3 Riley B,2,3 Straub RE,4 and Eaves LJ,1–3 1 Departments of Human Genetics, Virginia Commonwealth University, Richmond, Virginia 2 Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia 3 Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University, Richmond, Virginia 4 Clinical Brain Disorders Branch, IRP, NIMH, NIH, Bethesda, Maryland We have used a modern regression technique, Multivariate Adaptive Regression Splines (MARS), to analyze SNP markers from chromosomal region 6p22 of which some have been previously reported (ref.1) to be associated with schizophrenia and schizophrenia spectrum disorders. MARS simultaneously analyzes all inputs, in this case SNPs, and selectively eliminates variables contributing insignificantly to a fit criteria by internal cross-validation to arrive at a generalizable predictive model of the response. The dataset consisted of approximately 1,400 individuals from the Irish Study of High-Density Schizophrenia Families genotyped for 20 SNP markers. We compare the results obtained by this method, which treats family members as independent observations, to more traditional genetic association methods, which consider a familial structure (TRANSMIT, FBAT, & SDT). Our results show that 13 of the 20 SNPs were found to be associated with one or more schizophrenia diagnostic criteria by at least one of the methods. MARS identified 11 of these SNPs and an additional two not observed by other methods. TRANSMIT selected two SNPs not identified by any other method. We conclude that in comparison MARS performs as well as more popular methods for genetic association and could further be a useful method for whole genome SNP association studies where inherent low signal to noise ratios, multiple testing issues, and atypical pedigree structure can complicate analysis. References: 1) Straub et al., Am J Hum Genet, in press.

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P348 ASSOCIATION ANALYSIS BETWEEN THE POLYMORPHISM OF D6S470, D6S274, D6S296, D9S175 AND SCHIZOPHRENIA PATIENTS FROM SHANGHAI Zhang X-N,1 Jiang S-D,2 He X-H,1 Qian Y-P,2 Wang D-X,2 and Zuo J3 1 Department of Genetics, School of Medicine, Ningbo University, China 2 Department of Genetics, Shanghai Mental Health Center, China 3 Center of Genetic Medicine, School of Medicine, Fudan University, Shanghai, China For analyzing the probable susceptibility loci of schizophrenia loci on human chromosome 6, we genotyped one hundred and seventy-eight schizophrenia patients from Shanghai, including eighty-two chronic schizophrenics who had been suffering from the disease for longer than 10 years, and eighty-eight healthy controls, with four short tandem repeat (STR) markers: D6S470, D6S274, D6S296 and D9S175 by amplified fragment length polymorphism (AFLP). The allele 264bp of D6S296 was significantly more frequent in chronic schizophrenics (0.1688) than in healthy controls (0.0390, w2 ¼ 17.68, P < 0.001). Other allele frequencies did not differ between patient and control populations. Thus, we obtained a strong association between the chronic schizophrenics and the allele 264bp of D6S296 (RR ¼ 8.30, w2 ¼ 17.68, P < 0.001). The results suggest that D6S296 may be a susceptibility marker for schizophrenia on chromosome 6. This work was supported by the KC Wong Education Foundation Fund.

Poster Session 11: Neurobiology P349 FUNCTIONAL EFFECTS OF A TANDEM DUPLICATION POLYMORPHISM IN THE 50 FLANKING REGION OF THE DRD4 GENE D’Souza UM, Russ C, Tahir E, Browes C, Mill J, McGuffin P, Asherson PJ, and Craig IW Social, Genetic and Developmental Psychiatry Research Centre, Institute of Psychiatry, London, UK A tandem duplication of 120 bp was previously identified approximately 1.2 kb from the initiation codon in the 50 flanking region of the DRD4 gene. The frequency of the duplicated allele ranged from 0.4–0.81 in 11 populations and then later found to be associated with ADHD in children in one study. Our aim was to investigate the functional effects of this tandem duplication polymorphism at a cellular level. Oligonucleotide primers were designed flanking the duplication and PCR products were cloned into the luciferase vector pGL3Basic, sequenced and transiently transfected into a range of mammalian cell lines. These included HEK293 (human embryonic kidney), SH-SY5Y (human neuroblastoma), SK-N-MC (human neuroblastoma) and HeLa (human

adenocarcinoma), which were all found to endogenously express the DRD4 gene using Taqman real-time quantitative RT-PCR assays. Dual-luciferase reporter gene assays were carried out on cell lysates and the transfection efficiencies controlled for using Renilla luciferase. The results revealed the shorter construct (pGL3Basic-DRD4S) to have higher luciferase transcriptional activity than the longer construct (pGL3Basic-DRD4L, consisting of the tandem duplication) in the different cell lines tested and are represented as fold values to pGL3Basic. The results for the short and long construct are indicated for each cell line, respectively as follows: HEK293, 4.2  0.8; 2.4  0.2, SH-SY5Y, 13.1  2.0; 8.3  1.2, SK-N-MC, 12.8  1.3; 9.1  0.7 and HeLa, 24.7  1.5; 17.0  1.2. Significant differences (adjusted for multiple testing) in luciferase activity were observed between the long and short constructs at P < 0.0001 in SK-N-MC, SH-SY5Y and HeLa cells and at P ¼ 0.02 in HEK293 cells. Bioinformatics suggest that the tandem duplication binds to various transcription factors. Together with our findings on the functional effects of this polymorphism in cell lines, these data indicate that the duplication may have a potential role in regulating the expression of the DRD4 gene. P350 MOLECULAR CLASSIFICATION OF MENTAL DISORDERS BY GENE EXPRESSION PROFILES AND CHARACTERIZATION OF THE UNIQUENESS OF BIPOLAR DISORDER Iwamoto K,1 Kakiuchi C,1 Ikeda K,2 and Kato T1 1 Laboratory for Molecular Dynamics of Mental Disorders, Brain Science Institute, RIKEN, Saitama, Japan 2 Department of Ultrastructure and Histochemistry, Tokyo Institute of Psychiatry, Tokyo, Japan Molecular basis of the uniqueness of bipolar disorder and its similarity to the other two disorders, schizophrenia and major depression is poorly understood. We profiled gene expression profiles of autopsied prefrontal cortex provided by the Stanley Foundation Brain Collection. Number of samples that were successfully obtained gene expression profiles by HU95A chip (Affymetrix) was 50 (11 bipolar disorder, 11 major depression, 13 schizophrenia, and 15 control subjects). By comparing these gene expression profiles, we searched the bipolar disorder-specific gene expression changes as well as those shared with the other two disorders. We further report that mental disorders can be classified postmortem by comparing the expression of selected genes. The usefulness of the 40 selected genes for classification was confirmed by performing the cross-validation of 50 repetitions of the discriminant analyses by leave-one-out method, in which each sample is classified by the functions derived from all samples other than that sample. When same analysis was performed using 40 randomly selected genes, the correct classification ratio of the cross-validation was similar to by chance. These

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results suggest the 40 selected genes in our study would be useful for classification and prediction of unknown samples.

P351 PHARMACOGENOMICS OF ANTIDEPRESSANT DRUG RESPONSES McHugh P,1 Rogers G,1 Allington M,1 Cameron V,2 Edgar P,3 Begg E,4 Joyce P3 and Kennedy M1 1 Department of Pathology, Christchurch School of Medicine and Health Sciences, University of Otago, Christchurch, New Zealan 2 Department of Medicine, Christchurch School of Medicine and Health Sciences, University of Otago, Christchurch, New Zealan 3 Department of Psychological Medicine, Christchurch School of Medicine and Health Sciences, University of Otago, Christchurch, New Zealan 4 Department of Clinical Pharmacology, Christchurch School of Medicine and Health Sciences, University of Otago, Christchurch, New Zealand Genetic variation in individuals may affect their ability to respond to antidepressant drug treatment. We are currently developing two models, an embryonic stem (ES) cell-derived neuronal culture model and a rat model to understand the variable antidepressant drug responses that occur in individual humans. Microarray and Proteomic assays are being developed to look at genes and proteins that show altered expression after exposure of neuronal cells and rats to antidepressants. These genes will be reasonable candidates for harbouring variability that might account for inter-individual differences in antidepressant drug response. Proteomics is generally less sensitive, and therefore will sample a smaller range of expressed genes, although it has the advantage of identifying translated products that are likely to be functionally relevant in each cell. The transcriptome analysis is more sensitive but less discerning, as it interrogates any transcript that is present in the cell whether or not it is functionally important. However, the combined information from both approaches should point to a set of genes or pathways that undergo changes in expression in response to antidepressants. The ultimate goal of this project is to develop and apply two model systems to identify genes that may be relevant to clinical responses to antidepressant treatment. Genes identified in the two model systems may play a role in cellular and molecular responses to antidepressants, and therefore inherited variation in these genes may contribute to inter-individual variability in antidepressant response. As candidate genes are derived from the two model systems, polymorphic variants will be identified in the human equivalents. These will then be used in allelic association studies in a clinical research setting to test their validity and relevance to antidepressant drug response.

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P352 THE-1438-A/G SEROTONIN 2A RECEPTOR PROMOTER POLYMORPHISM AFFECTS PROMOTER EXPRESSION Parsons MJ,1 Makoff A,1 D’Souza U,2 Arranz MJ,1 and Kerwin R1 1 Department of Clinical Neuropharmacology, Institute of Psychiatry, London, UK. 2 Department of Molecular Genetics, SGDP Research Centre, Institute of Psychiatry, London, UK The 5-HT2A-receptor (5-HT2A-R) promoter polymorphism -1438-A/G is associated with numerous psychiatric disorders. Additionally, the 5-HT2A-R plays a potential role in clozapine response. The -1438-A/G polymorphism was found to affect the 5-HT2A receptor mRNA expression levels from human brain (Polesskaya and Sokolov, 2002, J Neuro Res, 67, 812-22) suggesting that the polymorphism has functional consequences on 5-HT2A-R gene expression. Conversely, the two -1438-A/G variants had equal levels of basal expression in a reporter gene assay [Spurlock et al., 1998: Mol Psy 3:42–49]. In order to clarify whether the polymorphism has functional effects at the promoter level we cloned part of the 5-HT2A-R promoter (1536 to 536) for both -1438-A/G variants into the following vectors: pCATbasic, pCAT-enhancer, and p-CAT-promoter. These vectors were transformed into SHSY-5Yand IMR-32 neuroblastoma cell lines (transformation into HeLa cells is currently underway) and CAT activity was determined using a CAT ELISA kit. pCAT expression levels were lower for the -1438-G variant within pCAT enhancer in SHSY-5Y cells (P < 0.005), with a trend in the pCAT basic vector (P < 0.08), suggesting that the -1438-G variant decreases basal promoter activity. Preliminary evidence suggests that there are no differences in the IMR32 cell line between the -1438-A/G variants. We are currently attempting to replicate these findings using the Luciferase receptor gene system in the same cell lines. P353 POLYMORPHISMS WITHIN NEURONAL GENES CORRELATING WITH PREDISPOSITION TO BEHAVIOURAL DISORDERS ACT AS NEURONAL SPECIFIC DIFFERENTIAL REGULATORS OF GENE EXPRESSION Quinn JP,1 MacKenzie A,2 Bubb VJ,1 and Scott A1 1 Physiological Laboratory & Dept Human Anatomy and Cell Biology, University of Liverpool, UK 2 Institute of Medical Sciences, Aberdeen, UK Genetic factors have been implicated in the aetiology of mental illness. Abnormalities in monoamine metabolism, in particular serotonin (5-HT) and dopamine have been implicated in the pathophysiology of many CNS related disorders. Clinical studies have suggested a polymorphism termed a variable number tandem repeat (VNTR) within intron 2 of the Serotonin transporter gene (5HTT) and the 30 untranslated region of the dopamine transporter (DAT1) gene

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are potentially associated with the susceptibility to such disorders. Although these clinical correlates have often been conflicting, the DAT 1 VNTR polymorphism has been more consistently correlated with attention-deficit hyperactivity disorder. Further the VNTR in the DAT1 gene can determine bioavailability of the transporters in vivo. Biochemically we have identified transcription factors binding the 5HTT VNTR by yeast one hybrid selection and demonstrated that a number of transcription factors will differentially regulate VNTR function. Previously clinical correlation with a specific disorder has been solely linked to copy number of the repeats, we have extended these studies further and demonstrated that individual repeat elements within the VNTR domain also differ in their enhancer activity in ES cells. This may in part explain the differential activity demonstrated by 5HTT VNTRs of different copy number [Fiskerstrand et al., 1999: FEBS Letters 458:171–174]. Thus clinical data should also address specific sequence of the VNTR in addition to copy number. We have demonstrated that these VNTR polymorphisms are functionally related in both binding similar transcription factors and in supporting tissue specific and differential enhancer activity. We have demonstrated that the 5HTT restricts marker gene expression in the developing CNS to areas associated with the initial endogenous 5-HTT expression [MacKenzie et al., 1999: Proc Natl Acad Sci 96:15251–15255]. Similarly the DAT 1 gene strongly enhances transcription of a marker gene within DA neurones in organotypic adult rat CNS cultures [Michelhough et al., 2001: J Neurochem 79:1033–1038]. Our data clearly indicates a potential mechanism by which such regulatory polymorphisms might influence severity, onset or susceptibility to disease. They can act to vary the active complement of these crucial neurotransmitter regulators in a tissue specific and concentration dependent manner. These VNTRs are found in numerous other genes and potentially define a novel regulatory domain.

P354 GENE EXPRESSION CHANGES IN HUMAN NEURONS PRODUCED BY ANTIPSYCHOTIC DRUG TREATMENT Widdern OV,1 Bo¨nisch H,2 Maier W,1 and Rietschel M1 1 Department of Psychiatry and Psychotherapy 2 Department of Pharmacology, University of Bonn, Germany Clinical response and patterns of side-effects are different to treatment with ‘classical’ (e.g., haloperidol) and novel (e.g., risperidone) antipsychotic drugs. Both show high affinity to G-protein coupled dopamine D2 receptors, which inhibit adenylyl cyclase. The further molecular mechanism of action however is not well understood yet. This study aimed to investigate the gene regulating effects of haloperidol vs. risperidone on differentiated human neuroblastoma cells in vitro. Retinoic acid-induced differentiated SKN-SH-SY5Y

cells were examined. We studied the differential gene expression profile of ‘treated’ and ‘untreated’ human neuronal cells after short time and long time ‘treatment’ under different pharmacological concentrations. The differential gene expression was assessed by cDNA-microarrays containing 588 genes (Neurobiology Atlas Array, Clontech). In cases of selected gene products RT-PCR-methods (TaqMan, Applied Biosystems) were used to decrease the detection threshold. Additionally the ProteinChip-technology (SELDI) was used for the protein expression profiling. Beside others we identified differentially expressed genes which are involved in complex signal transduction pathways and in the dopaminergic pathway (e.g., dopamine beta-hydroxylase, MAO, COMT).

P355 INTERPHASE FISH ANALYSIS OF EMBRYONIC CNS CELLS: EVIDENCE FOR HIGH LEVEL OF CHROMOSOMAL ANEUPLOIDY Yurov YB,1 Vostrikov VM,1 Monakhov VV,1 Sharonin VO2 and Vorsanova SG2 1 National Research Center of Mental Health, RAMS, Moscow, Russia 2 Institute of Pediatrics and Children Surgery, Russian Ministry of Health, Moscow, Russia Fluorescence in situ hybridization (FISH) was used to study interphase chromosomes in human embryonic central nervous system (CNS) cells cultured in vitro. DNA probes included (i) centromeric alphoid DNA probes for sex chromosomes (X and Y) and (ii) classical satellite DNA probe for chromosomes 1. Six primary cultures of embryonic human CNS cells [Vostrikov et al., 2002] were analyzed. Six control cell cultures obtained from human peripheral blood lymphocytes, six samples of human spermatozoa from healthy individuals and post-mortem brain cells of four individuals were used as control in FISH experiments. 3.000–10.000 hybridized cells were analyzed for each sample. The level of aneuploidy (per individual chromosome) was in the range of 0.1–0.4% in spermatozoa; 0.3– 0.8% in lymphocytes; 0.0–0.2% in post-mortem brain cells and 4–7% in embryonic CNS cells. However, significant levels of aneuploidy (0.5–4%) were detected in post-mortem brains of patients with schizophrenia (Yurov et al., 2001). Our results indicate that embryonic CNS cells and somatic or germ-line human cells differ in aneuploidy frequency. These data are in agreement with the results of Rehen et al. [2001] concerning chromosomal variations in neurons in mouse embryonic CNS. High levels of chromosomal aneuploidy in embryonic human neuronal cells could, therefore, lead to genetic mosaicism in fetal and, probably, adult CNS. ‘‘Cryptic’’ chromosomal mosaicism of the brain could have substantial effects on normal brain development and, there-

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fore, may have relevance to some neuropsychiatric diseases. Supported in part by grant Copernicus 2.

Poster Session 12: Animal Models P356 STUDY OF EXPRESSION PROFILES IN THE STRIATUM AND THE HIPPOCAMPUS OF NORMAL AND NEURODEVELOPMENTALLY COMPROMISED RATS USING CDNA MACROARRAY METHODOLOGY Gak E,1 Koronyo-Hamaoui M,1,2 Zuckerman L,3 Guetta E,1 Barkai G,1,2 Goldman,1,2 and Weiner I3 1 Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel Hashomer, Israel 2 Sackler Faculty of Medicine, Tel Aviv University, Israel 3 Psychobiology Unit, Department of Psychology, Tel Aviv University, Israel We have recently found that immune activation during pregnancy in rats by means of administration of the synthetic cytokine releaser poly i:c leads in the offspring to neurochemical and histological aberrations in the brain, as well as long term deficits in attention, memory and behavior. Moreover, these deficits were not present at puberty (35 days) but emerged at adulthood (90 days), therefore could be considered maturation-dependent. The present study used this animal model for a comparative analysis of multiple gene expression profiles in selected brain regions, striatum and hippocampus, from the offspring of poly i:c treated and control dams, in order to identify molecular mediators of neurodevelopmental processes leading to the manifestation of normal and abnormal phenotypes. To this end, we used cdna macroarrays clontech technology applied on hybond membranes (hybond-atlas rat 1.2 #7854) containing 1200 rat genes relevant to neuroresearch, and housekeeping genes for quantitative standardization of expression products. Brain sections were obtained from adult female rats after the behavioral test. Preparations from four matched brain-sections were pooled in equal proportions to avoid inter-individual variation. In two independent experiments we have found that the synapsins 1a and 1b were up-regulated in both the striatum and the hippocampus of poly i:c offspring. Several other mediators of synaptic remodeling were up-regulated in both these regions in comparison with the controls. In addition, several kinases associated with signal transduction and cell proliferation demonstrated poly i:c specific expression profiles. Although these findings need further validation by other molecular methodologies, they do suggest that prenatal poly i:c administration may interfere with neurodevelopmental processes involving neuronal connection formation and proliferation. Further study of this model in a more controlled and systematic experimental scheme is ongoing.

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P357 SUBLINES OF RATS WITH CONSTITUTIONALLY UPREGULATED AND DOWNREGULATED 5HT HOMEOSTASIS: DIFFERENCES IN ANXIETY AND EXPLORATORY BEHAVIOR Hranilovic D, Cicin-Sain L, Bordukalo T, and Jernej B Laboratory of Neurochemistry and Molecular Neurobiology, Rudjer Boskovic Institute, Zagreb, Croatia By the breeding selection for the extreme values of platelet 5HT level and platelet 5HT uptake two sublines of Wistarderived rats, with constitutionally high or low values of both parameters, have been developed. Molecular genetic studies demonstrated that the observed differences were underlied by differences in the expression of platelet 5HT transporter, at both protein and mRNA levels, between the sublines. Neurochemical studies indicated that similar differences between the sublines might be expected in the expression of neuronal 5HT transporter. In order to search for the potential differences in 5HT functioning in brains of the mentioned animals, we investigated two types of behavior known to be mediated by serotonin: exploratory behavior and anxiety. Exploratory behavior was investigated as number of nose pokes and number of rearings in a hole board. Level of anxiety was measured in zero-maze as number of transitions between open and close quadrants and percent of time spent in open area. Animals from ‘‘low-5HT’’ subline showed significantly higher exploratory behavior than animals from ‘‘high-5HT’’ subline: 9.5  0.83 vs. 5.3  0.73 nose pokes and 8.2  1.1 vs. 3.8  0.7 rearings, respectively (P < 0.001, N ¼ 26 per group). Accordingly, ‘‘low-5HT’’ rats demonstrated significantly lower level of anxiety than high-5HT rats: 7.3  1.35 vs. 1.3  0.3 transitions and 12.1  2.4 vs. 2.4  0.9 percent time in open, respectively (P < 0.001, N ¼ 26 per group). These preliminary results suggest that our selectively bred animals posses alterations in brain 5HT homeostasis and could serve as a useful model for studies of 5HT (dis)regulation. P358 TRANSGENIC MODELS TO DETERMINE BOTH EXPRESSION AND FUNCTION OF THE HUMAN TACHYKININ GENES IN VIVO MacKenzie A2 and Quinn JP1 1 Physiological Laboratory & Dept Human Anatomy and Cell Biology, University of Liverpool, UK 2 Department of Molecular and Cell Biology, University of Aberdeen, UK Towards an understanding of the mechanisms controlling PPTA expression we have generated a model to determine both the tissue specific and stimulus inducible expression of the Human PPT-A gene and to address the function of the tachykinin gene products. We introduced 380kb human yeast artificial chromosome (YAC) containing the PPTA gene tagged with a bacterial b-galactosidase gene into transgenic

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mice. This resulted in a pattern of LacZ expression in the central nervous system (CNS) remarkably similar to that reported for PPTA mRNA in the rodent [MacKenzie et al., 2000: Mol Cell Neurosci 16:620–630; MacKenzie and Quinn, Mol Cell Neurosci, in press]. Differences of LacZ expression occurred where the human gene drove expression in areas of the CNS not associated with strong PPTA expression in rodents but which have been shown to express PPTA in the human. Due to the sensitively of the marker gene we have also been able to extrapolate PPT gene expression in the embryo to several days prior to that currently in the literature using standard technologies such as immunohistochemistry and in situ [MacKenzie and Quinn, Mol Cell Neurosci, in press]. We can delineate tissue specific and stimulus inducible regulatory domains by deletion and mutation. Furthermore, because the introduction of the b-galactosidase gene into the human PPTA only affected exon 7, the integrity of much of the PPTA coding sequence, including those of exons 3 and 6 which encode for SP and NKA respectively, remains. We have demonstrated that our YAC construct expresses substance P (2). Current opinion within murine genetics now suggests that the over expression of genes may be very useful in determining gene function. We believe that these transgenic models will be invaluable in ascertaining the possible contributions of the PPTA gene in the progression of several disease states. We are now humanising the high affinity receptor for Substance P, NK1. Both human PPTA and NK1 loci will be crossed onto their respective knock-outs and then breed to have a humanised model on a KO background for analysis of tachykinin transmission. This will provide a better preclinical model for addressing pharmaceutical intervention in the role of tachykinins in a variety of disorders.

P359 ESSENTIAL ROLE OF LIMBIC CORTICOTROPIN-RELEASING HORMONE RECEPTOR 1 IN NEUROENDOCRINE ADAPTATION TO STRESS AND ANXIETY-RELATED BEHAVIOR Mu¨ller MB Molecular Neurogenetics Group, Max Planck Institute of Psychiatry, Mu¨nchen, Germany Corticotropin-releasing hormone (CRH) plays a key role in coordinating the responses to a variety of stress-associated stimuli. Recent clinical data implicate CRH in the pathophysiology of affective disorders. The effects of CRH are mediated via two receptors, CRHR1 and CRHR2. Conventional knockout of CRHR1 severely impairs the stress response of the hypothalamic-pituitary-adrenocortical (HPA) system and reduces anxiety. Part of the CRH effects on emotional behaviour may also be mediated via activation of the HPA system and subsequent glucocorticoid release. To genetically dissect CRH/CRHR1 pathways modulating be-

haviour from those regulating endocrine function we generated a region-specific knockout using the Cre/loxP system under the control of the CaMKII alpha promotor. In Crhr1loxP/loxPCaMKCre mutants Crhr1 function is inactivated postnatally in forebrain and limbic brain structures while sparing hypothalamic and pituitary expression sites so as to leave stress-induced activation of the HPA system intact. Crhr1loxP/loxPCaMKCre mutants display reduced anxiety while basal HPA system activity is unaltered. Limbic Crhr1 supplies regulatory features to the endocrine stress response as corticosterone levels were higher following ten minutes of restraint stress and remained elevated 90 minutes post-stress. Our data suppport a key role of limbic Crhr1 in modulating emotional behaviour, independently of HPA system function. Further, we provide evidence for a novel role of Crhr1 in central control of HPA system feedback and hormonal adaptation to stress.

P360 PARTICIPATION OF ENDOGENOUS REGULATORS OF APOPTOSIS IN MECHANISMS OF SPECIFIC BRAIN FUNCTIONS AT NORMAL AND PATHOLOGICAL CONDITIONS Sherstnev VV,1 Gruden MA,1 Storogeva ZI,2 Kostanyan IA,2 Proshin AT,1 Urasov VV,1 Gubskaya OB,3 Yakovleva NK,1 and Skvortcova VI1 1 P. K. Anokhin Institute of Normal Physiology, RAMS 2 M. M. Shemyakin and U. A. Ovchinikov Institute of Bioorganic Chemistry, RAS 3 State Medical University, Moscow, Russia Clinic-experimental investigation concerning participation of apoptotic factors proteins—S100b and HLDF—in mechanisms of brain specific activity and development of cerebral ischemia was performed. We revealed that application of protein S100b at proapoptotic dose (500 ng) at cerebellar vermis of adult Wistar rats caused the breaking of long-term and short-term habituation of the acoustic startlereaction and formation of fear-conditioned freezing. At antiapoptotic dose protein S100b (5 ng) stimulated elaboration of passive defense behavior. Peptide fragment of HLDF, named HLDF6, which possesses antiapoptotic activity at dose 100 mcg/kg, stimulated long-term memory in rats and mice C57Bl/6 and Wistar rats in the Morris water maze; at dose 3 mg/kg peptide it enhanced mice short-term performance in this memory task. During clinical-immunological observation of patients with acute ischemic stroke at first day after stroke, increase in S100b liquor content was revealed without change of HLDF content. Patient sera HLDF content was down compared to controls. Basic therapy didn’t change sera or liquor S100b content at 1–3 day of treatment. In contrast, therapy by natural neuroprotective drug ‘‘Semacs’’ had a positive clinical effect, which was accompanied by an increase of protein S100b and a decrease of HLDF in liquor

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without changing the HLDF content in sera of patients. The obtained data provide evidence that that both investigated factor-regulators of apoptosis are involved in neurochemical mechanisms of learning and memory in adult animals as well as in development of ischemic cerebral disturbances. Support by RFBR, grant *02-04-48847 and RHSF, grant *02-0600148a.

P361 ANIMAL MODELS ON AGGRESSIVE BEHAVIOR: FOCUS ON UNDERLYING DIMENSIONS AND Y CHROMOSOMAL EFFECTS IN MALE MICE te Boekhorst D,1 Rijsdijk FV,2 Veenema AH,1 Koolhaas JM,1 and Sluyter F2 1 Animal Physiology, Rijksuniversiteit Groningen, The Netherlands 2 SGDP Research Centre, Institute of Psychiatry, London, UK Violence is perceived as becoming an increasingly serious social issue. Although environmental factors seem to play an imminent role, several studies clearly show the importance of genetic variation in the aetiology. Thus, questions rise on the nature of gene-environment interplay and the specific genes (e.g., encoded proteins) involved. Actual identification of the alleged ‘aggression’ genes is a huge task in which especially mouse models are useful, since they share many genes with humans; with similar DNA sequences coding for structurally and functionally similar proteins. The aims of this study were to understand the factorial structure of offensive aggression in male mice and to determine Y chromosomal effects. We assessed several measures of aggressive behavior in a design focused on the environment in which the encounters take place. Thus, aggressive (A) and nonaggressive (NA) mice from one pair of selection lines (SAL&LAL, Dutch origin), as well as congenic Y chromosome lines (abb. SAL. LY&LAL. SY) were tested in 4 paradigms: the resident intruder, neutral cage, inverse resident intruder and a more naturalistic paradigm. Animals were tested twice per test, against standard opponents on consecutive days. Males were also tested against a female. Preliminary rotated principal component analyses reveal two factors: a general one which seems to identify mainly territorial aggression and a more extreme, almost pathological factor which seems to tap in a more unnatural dimension of aggressive behavior. The latter might provide a model for domestic violence. Y chromosomal effects on dimensions of aggression seem rather bizarre. Whereas Y chromosome polymorphisms have no effect on a NA background, they do seem to be important on an A background. Aggressive males with a NA-Y chromosome (SAL. LY) show slightly less territorial aggression, but far more pathological aggression than normal aggressive males.

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Poster Session 13: Ethics and Genetics of Behavior P362 CLINICIAN AND PATIENT ATTITUDES TOWARDS THE CLINICAL APPLICATION OF DNA TESTING FOR DIAGNOSIS, COUNSELING AND DRUG RESPONSE IN PSYCHIATRIC DISORDERS Bhatia P Department of Psychiatry, University of California San Diego Medical Center, La Jolla, California We explore attitudes in both psychiatric clinicians and patients towards the potential of clinical application of DNA testing for diagnosis and counseling as it relates to onset of psychiatric symptoms and prediction of drug response. For example, current genetic counseling is the care standard in the field of oncology. The BRCA1/2 genes and mutations and other risk factors have significant implications in counseling patients with breast and ovarian cancers, and can potentially influence the choice of chemotherapeutic agents. Since our current understanding of the genetics of psychiatric disorders is not quite as advanced, we argue that the identification of several genes is at hand, and the potential clinical application of that information may be near. The oligogenic nature of psychiatric disorders is such that DNA testing is more likely to take the form of panels of tests of multiple mutations in several genes. Such a panel would then ideally have probabilistic predictive value for possible clinical applications. These include: 1) clarification of diagnosis, 2) prediction of drug response and 3) risk testing. We explore the potential early application of such tests in a clinical setting. The most controversial and ethically complex of these applications is risk testing in asymptomatic individuals, and given the risks and limited knowledge, we argue this is premature at this time. However, diagnostic and pharmacogenomic applications have much lower risks and will likely soon have some clinical value. A model for such clinical application is presented as a genetic-based specialty clinic. In this proposed setting, DNA tests of a few genes with more robust reported associations are interpreted in the light of standardized diagnostic methods (SCID, DIGS, MAGIC) and detailed family history. Such a model may be useful for diagnostic clarification for first onset symptomatic patients towards clarification of diagnosis and probabilistic recommendations for drug treatment. This clinical consultative model is presented along with preliminary results of an attitude survey of clinicians and patients regarding its potential value and their concerns. P363 GENOMIC IMPRINTING, X-INACTIVATION AND MALE SEXUAL ORIENTATION Bocklandt S and Hamer DH 1 Laboratory of Biochemistry, National Cancer Institute, National Institutes of Health, Bethesda, Maryland

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Genomic imprinting of X-chromosome genes could lead to sex-specific gene expression, and is therefore a candidate mechanism for the regulation of sex specific traits, including sexual orientation. The existence of such imprinted X linked genes is indirectly supported by studies on the social skills of girls with Turner syndrome and the male/female ratio in the families of male-to-female transsexuals and male homosexuals. Since X-inactivation and genomic imprinting share several molecular mechanisms, we measured X-inactivation in the mothers of gay men. X chromosome inactivation was analyzed in 96 mothers of gay men compared to 108 control women matched for age and ethnicity. Skewing was assayed in white blood cell DNA by an androgen receptor gene assay and confirmed at the fragile X locus. The results of the two assays were highly correlated (Pearson correlation ¼ 0.74). We found a significant difference (P ¼ 0.004) in X chromosome skewing in the two groups. The mothers of gay men showed a bimodal distribution in which 14% of the cases displayed extreme skewing (more than 90% inactivation of one chromosome). The control women showed a normal distribution in which only 3% of the sample had extreme skewing. Analysis of mouthwash samples showed that individuals with extreme skewing in blood DNA also displayed higher skewing in buccal cell DNA (Pearson correlation ¼ 0.75). Analysis of 47 members of a large family suggests that the extreme skewing is shared by sisters of the mother, indicating that the effect is genetic and not caused by any biological influence of the gay son. However, it is not passed on to the next generation of daughters, indicating the skewing is not caused by a lethal mutation on the X chromosome. We are further investigating the genomic imprinting hypothesis using a full genome linkage scan on gay brother pairs, micro array gene expression analysis of cell lines derived from gay and straight men and their families, and sequencing and methylation analysis of candidate genes.

P364 ASSOCIATION STUDY BETWEEN THE T102C POLYMORPHISM OF THE 5-HT2A GENE AND SEVERE SUICIDE ATTEMPTS IN PSYCHIATRIC INPATIENTS Correa H,1,2 De Marco L,1 Boson W,1 Machado M,1 Noronha J,1 Lima V,1 and Romano-Silva MA1 1 Departamento de Farmacologia- Laborato´rio de Fa´rmacogene´tica-Universidade Federal de Minas Gerais-UFMG, Belo Horizonte, Brasil 2 Instituto de prevideˆncia dos Servidores de Minas Gerais-IPSEMG, Belo Horizonte, Brasil Central serotonergic dysfunction and genetic factors are associated with suicidal behavior in psychiatric patients. The objective of this study was to examine the association between the 5HT2A gene polymorphism (102T/C) and suicide in a sample of Brazilian psychiatric inpatients. Subjects

were: 95 schizophrenic, [(age; 43.3  7.8; 34 with a life-time history of suicide attempt (35.7%)], 78 major depressed [(age; 42.5  8.2; 32 with a life-time history of suicide attempt (41.1%)] and 52 healthy controls (age; 39  9.2). Diagnosis was based on a structured interview (MINIPLUS), according DSM-IV criteria, and patients underwent a semi-structured interview for suicide history assessment. Chi-square tests were used to compare frequencies. No differences were found in genotypic frequencies across patients and controls. Overall, no differeces were found between patients with a suicide attempt history (n ¼ 66) and without (n ¼ 107): TT [18 (27.3%), 30 (28%)], TC [35 (53%), 55 (51.4%)], CC [13 (19.7%), 22 (20.5%)]. Neverthless, patients with a history of severe suicide attempts [lethality >3; (n ¼ 32)] and patients without such a history (n ¼ 107) exhibited different genotypic frequencies (P < 0.01), TT [12 (37.5%), 30 (28%)], TC [17 (53%), 55 (51.4%)], CC [3 (9.4%), 22 (20.5%)]. These preliminary results showed that 5HT2A gene polymorphism (102T/C) may be involved in the genetic susceptibility to suicidal behavior.

P365 MULTILEVEL ANALYSIS OF AN INTER-FAMILIAL SLEEPINESS-ALERTNESS QUESTIONNAIRE De Valck E and Cluydts R Department of Cognitive and Physiological Psychology, University of Brussels (VUB), Belgium We report on an exploratory study on daytime sleepiness/ alertness within 219 Belgian families. Aim of the study is to identify the impact of genetic and stable environmental factors in the subjective daytime sleepiness/alertness dimension. Classic sleep-wake regulation models make no distinction between state (short-term fluctuations) and trait (stable and person-specific) aspects in daytime sleepiness/alertness. Recent studies however suggest genetic components to be involved. Within each of the 219 families studied, a parent between 46 and 74 years (M ¼ 59.2; SD ¼ 7.4) and one child between 21 and 51 years of age (M ¼ 32.9; SD ¼ 6.1) completed the Epworth Sleepiness Scale (ESS), the Hyperarousal Scale, the Pittsburgh Sleep Quality Inventory (PSQI), the Pre-Sleep Arousal Scale (PSAS), the Sleep-Wake Activity Inventory (SWAI), the Profile of Mood States (POMS) and the Athens Insomnia Scale (AIS). Using the multilevel analysis technique (MLwiN1.1), a random intercepts model with 2 levels (persons within families) for the ESS-score as the response variable, is tested. It is shown that the variance between families is significant (3.354; P 160). Two markers, D4S2460 and D14S65, were significant at both the original and replication individual genotyping stages, but failed to show a TDT association. Power analyses showed that our most powerful sample is, in fact, our replication sample (stages 2 and 4), with 100%, 100% and 98% power to detect a QTL with 5%, 2.5% and 1% heritability, where D’ is 1.0. Even when D0 is 0.5, our replication sample remains the most powerful, with power estimates of 100%, 92% and 54% respectively. In order to ensure we had not been unnecessarily stringent at stage 1, thereby increasing the number of false negative results, we have reduced our significance level at stage 1 to 0.1, so that a further 53 markers were tested in our replication sample (stage 2). Subsequently, markers had to yield a significant association at the P < 0.05 level. Relaxing the stringent criteria in this way at stage 1 yielded additional markers that progressed through stage 4 but again they did not pass the final TDT hurdle. We suggest that the problem is not likely to be ethnic stratification but may be the lack of power for the TDT. We are currently examining additional samples in an attempt to resolve these issues.

investigated scales, show significant differences between the different knowledge groups in the direction of the correlation: psychiatric genetic research (F ¼ 6.4, P ¼ 0.000), predictive testing (F ¼ 16.3, P ¼ 0.000), prenatal testing (F ¼ 26.2, P ¼ 0.000) and access to genetic information. (F ¼ 42.5, P ¼ 0.000). For a further analyzes of the influence of knowledge on attitudes in the field of psychiatric genetics, knowledge about schizophrenia and ethical standards in the application of psychiatric genetics was tested in 88 medical students before and after a short teaching program. Before the intervention the knowledge about schizophrenia was alarmingly low and misbeliefs with respect to clinical symptoms and course of schizophrenia widespread. Although knowledge could be significantly increased common misbeliefs showed to persist in a substantial part of the students. Our findings show that knowledge influences attitudes and furthermore indicate that specific training programs are warranted to fight widespread misbeliefs.

P369 KNOWLEDGE INFLUENCES ATTITUDES TOWARDS PSYCHIATRIC GENETICS Illes F,1 Rietz C,2 Matschinger H,3 Rudinger G,2 Angermeyer M,3 Maier W,1 and Rietschel M1 1 Department of Psychiatry, University of Bonn, Germany 2 Institute of Psychology, University of Bonn, Germany 3 Department of Psychiatry, University of Leipzig, Germany

P370 POLYMORPHISMS IN THE PROMOTERS OF THE SEROTONIN TRANSPORTER GENE AND MAO-A GENE AND THEIR RELATIONSHIP TO DIMENSIONS OF TEMPERAMENT MEASURED BY TCI, NEO-FFI, AND EPQ-R IN HEALTHY VOLUNTEERS Samochowiec J,1 Ryz˙ewska A,1 Syrek S,1 Parus M,1 Kucharska-Mazur J,1 Kamin˜ski R,1 Horodnicki J,1 Rybakowski F,2 Rybakowski J,2 Czerski P,2 Wernicke C,3 Hauser J,2 and Zakrzewska M4 1 Departement of Psychiatry, Pomeranian Academy of Medicine, Poland 2 Departement of Psychiatry, Medical Academy Poznan˜, Poland 3 Departement of Neuropsychobiology, Free University of Berlin, Germany 4 Departement of Psychology, University of Adam Mickiewicz, Poznan˜, Poland

In the framework of the German Human Genome Project we conducted a study to assess the attitudes towards psychiatric genetic research and testing and to identify factors influencing them in a representative sample of 3077 persons of the German general population. One factor assumed to influence the attitudes is knowledge about psychiatric disorders and genetics, which was assessed by questions about psychiatric illnesses and genetics. Our results show that a higher knowledge concerning psychiatric illnesses and genetics is correlated with more critical -but still positive- attitudes towards psychiatric genetic research (r ¼ 0.200, P ¼ 0.000), predictive testing (r ¼ 0.125, P ¼ 0.000), prenatal testing (r ¼ 0.255, P ¼ 0.000) and access to genetic information (r ¼ 0.323, P ¼ 0.000). Further analyzes concerning the means of the

Several reports suggest that polymorphisms in monoamine genes show an association with personality dimensions. We study an association between temperament dimensions and polymorphisms of the serotonin transporter and MAO-A. The personality traits were measured by the TCI and NEO Five Factor Inventory (NEO—FFI) and the Eysenck Personality Questionnaire-Revised (EPQ-R). The group of 100 healthy volunteers was representative for the population of the city of Szczecin in sex, age and education dividing. There were 53 females and 47 males, the mean age was 42  17 years. The post hoc exploration in the Tuckey test indicated that males with higher scores in Neuroticism scale in EPQ-R and NEO—FFI (P ¼ 0.024, P ¼ 0.042 respectively), have MAO-A with lower activity as well as those

Abstracts

possessing high scores on RD3 TCI subscale—attachment, who prefer intimacy over privacy (P ¼ 0.018). Females possessing the same MAO-A alleles show higher scores on NS4 subscale (P ¼ 0.02) and RD4 (P ¼ 0.035), tend to be more irritable and disorderly. In contrast males with higher activity of MAO-A prove to have more fear of uncertainty (HA2; P ¼ 0.012) i.e. they can not tolerate uncertainty, unfamiliar circumstances that are potentially dangerous. Both genders possessing ‘‘long’’ (L/L) alleles of the serotonin transporter seem to be dependent on emotional support and approval from others. Due to our small sample those findings should be regarded as preliminary. Supported by grants: KBN 3P05D 146 22 and H01F 030-19, BMBF 01/ 063.

P371 THE ATTITUDES OF TURKISH PSYCHIATRISTS TOWARDS THE GENETICS OF MENTAL ILLNESSES Saylan M Department of Psychiatry, Istanbul medical faculty, Turkey Prejudges about mental illnesses could negatively influence its prognosis by decreasing accessibility to treatment resources. However, early recognition and treatment intervention may improve the outcome and minimise the disabilities. The results of recent researches on the genetics contributed to the comprehension of pathogenesis and aetiology of mental disorders. The identification of susceptibility genes for mental illnesses may cause a more biological concept of the disease, which may lead to either a decrease or an increase of stigmatisation of patients. The progresses in the genetics of mental disorders spontaneously reveal also some ethical questions that clinician will have to resolve in the future. Opinions of clinicians will be very important to guide future genetic researches and their clinical applications. In Turkey, there are approximately 1200 psychiatrists who practice in 120 institutions and private offices. The number of psychiatrist per 100.000 is less than 1 based on WHO data. We are conducting an explorative survey to assess the attitudes and expectations and fears of Turkish psychiatrists towards psychiatric genetics research and its clinical applications e.g., predictive genetic testing. We requested psychiatrists to fill the Turkish version of Gen-Ethics Questionnaire. The questionnaire has been recently developed in Rheinische Friedrich-Wilhelms-Bonn University, Department of Psychiatry. It consists of 10 different parts. We performed within group analysis to assess the effect of gender, age, marital status, believe in religion on the answers. Results: 139 psychiatrist filled out the questionnaire. Most of the Turkish Psychiatrists in the survey agree with the protection of genetic privacy but they also want that the results of a psychiatric genetic investigation should be shared between

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family members (%47). They approve genetic research (%75) but oppose the commercialization of genetic information. They support prenatal and presymptomatic genetic testing for mental and medical illnesses (%47). Female Psychiatrists are more reserved to have children if they have a risk of developing schizophrenia (%70 vs %30).

P372 RELEVANCE AND ACCEPTABILITY OF GENETIC TESTING FOR SUSCEPTIBILITY FOR NEUROLOGICAL IMPAIRMENT IN OCCUPATIONAL HEALTH Van Damme K,1 and Casteleyn L2 1 Center for Human Genetics, University of Leuven, Belgium 2 Epidemiology and Social Medecine, University of Antwerp, Belgium The simultaneous protection of both health and employment of each individual employee, irrespective of any shortcomings he or she may have, must form the core objective in occupational medicine. Neurological impairments may affect fitness at work. Neurological impairments can also be a consequence of occupational exposures. Susceptibility for neurological impairments related to monogenic or polygenic disorders or to genetic metabolic variants may therefore be of concern in occupational health. A methodology is presented allowing to assess the relevance and acceptability of genetic tests to predict neurological impairment in occupational health. Accuracy, need, relevance and consequences of these tests and the decision making processes are analysed to determine the level of consistency with a set of predefined social values. Although correlations can be demonstrated between certain exposure induced disorders and specific genetic traits, testing only has a low predictive value at the individual level. Hitherto, genetic test results cannot form a reliable basis for excluding potential employees from certain jobs to prevent occupation-related illnesses. Also, in a protective approach to occupational health, genetic tests to predict future neurological impairment irrespective of occupational exposure but due to certain inherited diseases must not have a place in occupational health practices. In contrast to clinical medicine, the principle of informed consent may not be used as a major regulatory principle in occupational settings, especially because of the specific context of power inequality.

P373 A GABRA6 CODING VARIANT IS ASSOCIATED WITH THE NEO-PI DOMAIN NEUROTICISM, A RISK FACTOR FOR DEPRESSION Villafuerte S,1 Sen S,2 Nesse RM,3,4 Hopcian J,7 Gleiberman L,5 Weder AB,5 and Burmeister M1–3,6

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Mental Health Research Institute, University of Michigan, Ann Arbor, Michigan 2 Neuroscience Program, University of Michigan, Ann Arbor, Michigan 3 Department of Psychiatry, University of Michigan, Ann Arbor, Michigan 4 Department of Psychology and Institute for Social Research, University of Michigan, Ann Arbor, Michigan 5 Department of Internal Medicine, University of Michigan, Ann Arbor, Michigan 6 Department of Human Genetics, University of Michigan, Ann Arbor, Michigan 7 Kalamazoo College, Kalamazoo, Michigan Psychiatric disorders are considered to be influenced by multiple genes and the environment. An increased interest has arisen in the study of personality traits as risk factors that are correlated with depression and/or severity of depression. The strong genetic basis of such traits increases the power to detect genes that confer vulnerability to depression. As has been proposed, high scorers of Neuroticism, measured by the NEO Personality Inventory (NEO-PI), have shown a significant and consistent association with depression. The Gamma-aminobutyric acid (GABA) system has been extensively studied in psychiatric disorders such as alcoholism, anxiety and most recently in unipolar depression where cortical GABA levels are reduced. Furthermore, evidence for linkage to bipolar disorder has been reported by several independent studies to chromosome 5q. These lines of evidence prompted us to investigate a coding SNP, Pro385Ser, located in the second intracellular domain of the GABA A6 receptor (GABRA6) subunit adjacent to a putative phosphorylation site, in 391 subjects of a large community sample (Tecumseh sample) who completed the NEO-PI questionnaire. The more common, Pro-Pro genotype was associated with significantly higher mean Neuroticism scores (P ¼ 0.007). Within the Neuroticism domain, the facets Anxiety, Depression, Hostility, and Vulnerability were associated with GABRA6 Pro-Pro genotype (P ¼ 0.026, P ¼ 0.014, P ¼ 0.011 and P ¼ 0.013, respectively). Our results suggest that GABRA6 should be investigated as a candidate gene for depression and bipolar disorder.

P374 PROTOCADHERINX/Y STRUCTURE AND SEQUENCE DIVERGENCE IN HOMO SAPIENS RELATIVE TO OTHER GREAT APES Williams NA and Crow TJ POWIC, Dept. of Psychiatry, University of Oxford, Warneford Hospital, Oxford, UK The Xq21.3/Yp11.2 block of homology is Homo sapiensspecific and genes located here are of particular interest when investigating genetic regulation of human-specific and sexspecific traits. ProtocadherinX/Y (PCDHX/Y), a cell adhesion molecule, is expressed predominantly in the foetal and adult brain and is active on both the X and Y chromosomes. Initial tests suggest human PCDHX escapes X-inactivation. To identify hominid-specific and human X/Y-specific changes we identified and analysed chimpanzee (Pan troglodytes) and gorilla (Gorilla gorilla) genomic homologues of PCDHX/Yexons. We detected a single sequence from males, consistent with the hypothesis that the PCDHX/Y homologue is present only on their X chromosome (and thus subject to X-inactivation). Comparison of chimp, gorilla and human sequences reveals a high ratio of non-synonymous to synonymous changes in PCDHY (possible evidence of positive selection) although tests suggest this sequence divergence is not significant possibly due to the relatively short (approximately three million years) divergence time of hominid PCDHX and PCDHYand/or a higher male to female mutation rate. However we note some changes may alter PCDHY properties e.g., different initiator methionines, and different stop codons in some transcripts. We also detect structural changes-PCDHY has lost two exons due to a chromosomal deletion of 108 kb. In contrast, we show significant negative (or purifying) sequence selection occurred after the split of the lineages leading to gorillas and chimps/hominids. The apparent loss of negative selection between chimp and human sequences may correlate with a change in regulation and/or function of the proto-PCDHX/Y gene during early hominid evolution. These sequence and structure changes and alteration of X-inactivation status may be relevant to the evolution of human-specific characteristics of the brain as well as those characteristics that differ quantitatively between the sexes.