Genome-wide association study identifies a potent locus associated with human opioid sensitivity.

Opioids, such as morphine and fentanyl, are widely used as effective analgesics for the treatment of acute and chronic pain. In addition, the opioid system has a key role in the rewarding effects of morphine, ethanol, cocaine and various other drugs. Although opioid sensitivity is well known to vary widely among individual subjects, several candidate genetic polymorphisms reported so far are not sufficient for fully understanding the wide range of interindividual differences in human opioid sensitivity. By conducting a multistage genome-wide association study (GWAS) in healthy subjects, we found that genetic polymorphisms within a linkage disequilibrium block that spans 2q33.3-2q34 were strongly associated with the requirements for postoperative opioid analgesics after painful cosmetic surgery. The C allele of the best candidate single-nucleotide polymorphism (SNP), rs2952768, was associated with more analgesic requirements, and consistent results were obtained in patients who underwent abdominal surgery. In addition, carriers of the C allele in this SNP exhibited less vulnerability to severe drug dependence in patients with methamphetamine dependence, alcohol dependence, and eating disorders and a lower 'Reward Dependence' score on a personality questionnaire in healthy subjects. Furthermore, the C/C genotype of this SNP was significantly associated with the elevated expression of a neighboring gene, CREB1. These results show that SNPs in this locus are the most potent genetic factors associated with human opioid sensitivity known to date, affecting both the efficacy of opioid analgesics and liability to severe substance dependence. Our findings provide valuable information for the personalized treatment of pain and drug dependence.

DPP6 as a candidate gene for neuroleptic-induced tardive dyskinesia.

We implemented a two-step approach to detect potential predictor gene variants for neuroleptic-induced tardive dyskinesia (TD) in schizophrenic subjects. First, we screened associations by using a genome-wide (Illumina HumanHapCNV370) SNP array in 61 Japanese schizophrenia patients with treatment-resistant TD and 61 Japanese schizophrenia patients without TD. Next, we performed a replication analysis in 36 treatment-resistant TD and 138 non-TD subjects. An association of an SNP in the DPP6 (dipeptidyl peptidase-like protein-6) gene, rs6977820, the most promising association identified by the screen, was significant in the replication sample (allelic P=0.008 in the replication sample, allelic P=4.6 × 10(-6), odds ratio 2.32 in the combined sample). The SNP is located in intron-1 of the DPP6 gene and the risk allele was associated with decreased DPP6 gene expression in the human postmortem prefrontal cortex. Chronic administration of haloperidol increased Dpp6 expression in mouse brains. DPP6 is an auxiliary subunit of Kv4 and regulates the properties of Kv4, which regulates the activity of dopaminergic neurons. The findings of this study indicate that an altered response of Kv4/DPP6 to long-term neuroleptic administration is involved in neuroleptic-induced TD.

Schizophrenia with the 22q11.2 deletion and additional genetic defects: case history.

The 22q11.2 deletion is the most prominent known genetic risk factor for schizophrenia, but its penetrance is at most approximately 50% suggesting that additional risk factors are required for disease progression. We examined a woman with schizophrenia with this deletion for such risk factors. She had high plasma pentosidine levels ('carbonyl stress') and a frameshift mutation in the responsible gene, GLO1. She also had a constant exotropia, so we examined the PHOX2B gene associated with both schizophrenia and strabismus, and detected a 5-alanine deletion. We propose that the combination of these genetic defects may have exceeded the threshold for the manifestation of schizophrenia.

A nonsynonymous polymorphism in cannabinoid CB2 receptor gene is associated with eating disorders in humans and food intake is modified in mice by its ligands.

Marijuana use activates cannabinoid receptors (CB-Rs) producing several behavioral effects related to addiction, mood, and appetite. We investigated the association between CNR2 gene, which encodes cannabinoid CB2 receptor (CB2-R) and eating disorders in 204 subjects with eating disorders and 1876 healthy volunteers in Japanese population. The effect of treatment with CB2-R ligands on mouse food consumption was also determined. The CB2-R ligands used suppressed food intake in a time- and strain-dependent manner when food was available ad libitum and during the 12-h fast except, AM 630-the CB2-R antagonist that stimulated food consumption in food-deprived mice. There is an association between the R63Q polymorphism of the CNR2 gene and eating disorders (P = 0.04; Odds ratio 1.24, 95% CI, (1.01-1.53). These results suggest that cannabinoid CB2-R is involved in the endocannabinoid signaling mechanisms associated with the regulation of food intake and in eating disorders.

Meta-analysis of 32 genome-wide linkage studies of schizophrenia.

A genome scan meta-analysis (GSMA) was carried out on 32 independent genome-wide linkage scan analyses that included 3255 pedigrees with 7413 genotyped cases affected with schizophrenia (SCZ) or related disorders. The primary GSMA divided the autosomes into 120 bins, rank-ordered the bins within each study according to the most positive linkage result in each bin, summed these ranks (weighted for study size) for each bin across studies and determined the empirical probability of a given summed rank (P(SR)) by simulation. Suggestive evidence for linkage was observed in two single bins, on chromosomes 5q (142-168 Mb) and 2q (103-134 Mb). Genome-wide evidence for linkage was detected on chromosome 2q (119-152 Mb) when bin boundaries were shifted to the middle of the previous bins. The primary analysis met empirical criteria for 'aggregate' genome-wide significance, indicating that some or all of 10 bins are likely to contain loci linked to SCZ, including regions of chromosomes 1, 2q, 3q, 4q, 5q, 8p and 10q. In a secondary analysis of 22 studies of European-ancestry samples, suggestive evidence for linkage was observed on chromosome 8p (16-33 Mb). Although the newer genome-wide association methodology has greater power to detect weak associations to single common DNA sequence variants, linkage analysis can detect diverse genetic effects that segregate in families, including multiple rare variants within one locus or several weakly associated loci in the same region. Therefore, the regions supported by this meta-analysis deserve close attention in future studies.

Expression profiling of genes related to asthma exacerbations.

BACKGROUND: Asthma is a chronic airway inflammatory disease; however, the molecular mechanisms that underlie asthma exacerbation are only partially understood. OBJECTIVE: To identify gene expression signatures that reflect the acute exacerbation of asthma, we examined the differential expression of genes during asthma exacerbation and stable condition by using microarray analysis. METHODS: The subjects were mite-sensitive asthmatic children and non-asthmatic control children. The children were divided into four groups (AE: asthma exacerbation, n=12; SA: stable asthma, n=11; IC: infected control, n=6; and NC: non-infected control, n=5). Total RNA was extracted from peripheral blood mononuclear cells and subjected to microarray analysis with Illumina Human Ref8 BeadChip arrays. Welch's t-test was performed to identify genes whose expression was altered during asthma exacerbation. Quantitative real-time RT-PCR was performed on samples collected from 43 asthmatic children and 11 control children to verify the microarray results. RESULTS: The expression of 137/16 genes was significantly up/down-regulated during asthma exacerbation assessed by microarray analysis. Of the genes, 62 were also differentially expressed during upper respiratory infection. Many of the asthma exacerbation related genes were involved in defence responses and responses to external stimuli, but these associations disappeared after excluding the infection-related genes. Quantitative real-time RT-PCR confirmed that the genes related (S100A8 and GAS6) and unrelated to infections (CD200 and RBP7) were differentially expressed during asthma exacerbation (P<0.01). CONCLUSIONS: Previously unidentified immune responses during asthma exacerbation may provide further clarification of the molecular mechanisms underlying asthma.

Associations between decay-accelerating factor polymorphisms and allergic respiratory diseases.

BACKGROUND: Allergic diseases such as asthma and allergic rhinitis are major causes of morbidity in developed countries. The pathology underlying allergic respiratory diseases is considered to be IgE-mediated type I allergy characterized by mucosal inflammation that occurs in response to allergen exposure. They are common diseases involving a complex inheritance. Complement systems are known to play an important role in allergic diseases. Decay-accelerating factor (DAF) is important for the regulation of the complement system and is a good candidate for determining the susceptibility to allergic diseases. OBJECTIVE: The present study aimed to investigate whether polymorphisms in the DAF gene are associated with allergic respiratory diseases in the Japanese population. METHODS: We performed mutation screenings of DAF and conducted a tag single-nucleotide polymorphisms (SNP) association analysis for 684 unrelated adult individuals with seasonal allergic rhinitis (SAR) with Japanese ceder pollen, 188 mite-sensitive adults with asthma, and 346 unrelated non-allergic healthy controls. RESULTS: DAF is located in the tight linkage disequilibrium (LD) block spanning 62 kb. The tag SNP analysis revealed that rs10746463 was significantly associated with SAR (P=0.00033) and mite-sensitive adult asthma (P=0.044). The rs2564978 and rs3841376 haplotypes, which are located in the promoter region of DAF, were in complete LD with rs10746463 (r2=1). Luciferase reporter assays with constructs containing the 5' flanking regions of DAF showed that the plasmid with rs2564978 C/rs3841376 deletion (the risk haplotype) had a statistically significantly lower transcriptional activity than that containing the rs2564978 T/rs3841376 insertion. CONCLUSIONS: Our results suggest that DAF is one of the genes involved in conferring susceptibility to allergic respiratory diseases and show that decreased levels of DAF may be associated with the enhanced specific IgE responses occurring in allergic diseases in the Japanese population.

Association of polymorphisms in the haplotype block spanning the alternatively spliced exons of the NTNG1 gene at 1p13.3 with schizophrenia in Japanese populations.

Chromosome 1p13 is linked with schizophrenia in Japanese families, and one of the candidate genes in this region is the netrin G1 (NTNG1) gene at 1p13.3. Associations of 56 tag single-nucleotide polymorphisms (SNPs) with schizophrenia were explored by transmission disequilibrium analysis in 160 Japanese trios and by case-control analysis in 2,174 Japanese cases and 2,054 Japanese controls. An association between SNP rs628117 and schizophrenia was identified by case-control comparison (nominal allelic p=0.0009; corrected p=0.006). The associated polymorphism is located in intron 9 and in the haplotype block encompassing the alternatively spliced exons of the gene. Allelic association of a different SNP in the same haplotype block in Japanese families was previously reported. These findings support that the NTNG1 gene is associated with schizophrenia in the Japanese.

RGS4 is not a susceptibility gene for schizophrenia in Japanese: association study in a large case-control population.

The regulator of the G-protein signaling 4 (RGS4) has been implicated in the susceptibility to schizophrenia. RGS4 interacts with ErbB3 that acts as receptors for neuregulin 1 and these proteins may play a role in the pathogenesis of schizophrenia via glutamatergic dysfunction. Recently, two meta-analysis studies provided different interpretations for the genetic association between RGS4 and schizophrenia. We attempted to confirm this association in a case-control study of 1918 Japanese patients with schizophrenia and 1909 Japanese control subjects. Four widely studied single nucleotide polymorphisms (SNPs) were genotyped, and none showed association with schizophrenia. SNP 1 (rs10917670), p=0.92; SNP 4 (rs951436), p=0.91; SNP 7 (rs951439), p=0.27; and SNP 18 (rs2661319), p=0.43. A haplotype block constructed by these SNPs spans the 5' flanking region to the 5' mid-region of the RGS4 gene. Previous meta-analysis showed that both two major haplotypes of this block were risk haplotypes. The two common haplotypes were observed in the Japanese population. However, neither haplotype was significantly associated with schizophrenia. We conclude that the common haplotypes and SNPs of the RGS4 gene identified thus far are unlikely to contribute to the genetic susceptibility to schizophrenia in the Japanese population.

PICK1 is not a susceptibility gene for schizophrenia in a Japanese population: association study in a large case-control population.

The protein interacting with C-kinase 1 (PICK1) has been implicated in the susceptibility to schizophrenia. PICK1 interacts with enzymes and receptors that play roles in the pathogenesis of schizophrenia via glutamatergic dysfunction. Recently, two studies reported associations between schizophrenia and two PICK1 gene polymorphisms, rs3952 in Chinese and Japanese populations and rs2076369 in a Japanese population. We attempted to confirm these associations in a case-control study of 1765 Japanese patients with schizophrenia and 1851 Japanese control subjects. Neither polymorphism was associated with schizophrenia (rs3952, p=0.755; rs2076369, p=0.997). A haplotype block with these polymorphisms spanning the 5' region of the PICK1 gene showed high linkage disequilibrium in the Japanese population (D'=0.98, r(2)=0.34); however, neither haplotype was significantly associated with schizophrenia. We conclude that the common haplotypes and polymorphisms of the PICK1 gene identified thus far are unlikely to contribute to genetic susceptibility to schizophrenia in the Japanese population.

Association between severity of alcoholism and the A1 allele of the dopamine D2 receptor gene TaqI A RFLP in Japanese.

The allelic association of TaqI A restriction fragment length polymorphism (RFLP) of the dopamine D2 receptor gene with alcoholism was examined in 78 Japanese alcoholics and compared with Japanese controls. A significantly higher frequency of the A1 allele (0.42) was found in 100 Japanese unscreened controls compared with those reported in white populations. Among 70 alcoholics whose severities were determined, the A1 allele was present in 77% of 43 more severe alcoholics and in 59% of 27 less severe alcoholics. The A1 allele was present significantly less frequently in the alcoholics at the age of 60 or older (42%), compared with those under the age of 60 (74%). In the subjects under the age of 60, the A1 allele was present in 83% of the 35 more severe alcoholics, being significantly more frequent than in 60% of the 35 nonalcoholic controls. All of the 7 alcoholics homozygous for the A1 allele were classified as severe. The average severity of alcoholism increased in the order A2/A2, A1/A2, and A1/A1 genotypes. These data suggest that the A1 allele is associated with severe alcoholism in the Japanese population and that the effect is related to or has a linkage disequilibrium with a genetic factor that has a small but not negligible additive effect on alcoholism.

An insertion/deletion polymorphism in the angiotensin converting enzyme gene is associated with both brain substance P contents and affective disorders.

Because of a potent action of angiotensin converting enzyme (ACE) to degrade substance P (SP) and an association of the insertion/deletion (I/D) polymorphism of the ACE gene with ACE activity, an association between the SP level and the ACE I/D polymorphism were examined using 20 human postmortem brain samples. The results showed a significant association between the polymorphism and SP levels in the basal ganglia and substantia nigra, where both ACE and SP concentrate, and a higher SP level in the subjects with the DD genotype than in those with the II genotype, with an intermediate level in heterozygotes. Associations of the polymorphism with schizophrenia and affective disorders were also investigated in 292 unrelated Japanese schizophrenics, 65 patients with affective disorders, and 579 controls. The D allele was significantly more frequent in the patients with affective disorders than in the controls (p < .02), and the DD genotype was significantly more frequent in the patients with affective disorders than in the controls (p < .002). There is no significant difference in the frequencies of the allele and the genotype between the controls and schizophrenics. These results suggest that the ACE I/D polymorphism is one of the genetic factors for an interindividual variability of brain SP levels, and that the ACE polymorphism may contribute to the susceptibility to affective disorders.

Association between serotonin transporter gene polymorphism and smoking among Japanese males.

The serotoninergic system may be involved in smoking behavior because nicotine increases brain serotonin secretion, nicotine withdrawal decreases serotonin levels, and a selective serotonin reuptake inhibitor antagonizes the response to nicotine. Compared with the L allele, the S allele of the polymorphism in the upstream regulatory region of the serotonin transporter gene is associated with decreased transcription efficiency of the 5-HTT gene promoter. We examined this polymorphism in a Japanese population consisting of 387 males from two different areas in Japan. The L allele was observed significantly more often in smokers (21%) than in nonsmokers (lifetime nonsmokers + ex-smokers, 14%; P = 0.005). The presence of the L allele (the L/L + L/S genotypes) was also significantly increased in smokers (37%) compared with that in nonsmokers (24%; P = 0.003). The present study suggests that individuals with the S/S genotype are less inclined to smoke and/or can more easily stop smoking than others, supporting a role of the serotoninergic system in smoking behavior.

Apolipoprotein(a) and pentanucleotide repeat polymorphisms are associated with the degree of atherosclerosis in coronary heart disease.

To evaluate whether a high level of lipoprotein(a) (Lp(a)) is a risk for the development of coronary heart disease (CHD), 94 Japanese patients and 64 age-matched Japanese controls, diagnosed after coronary angiography (CAG), were analyzed with special reference to the relations between the degree of atherosclerosis, Lp(a) levels and the apolipoprotein(a) (apo(a)) genotypes. the degree of atherosclerosis was evaluated based on CAG findings in the following three ways: the number of diseased vessels, the Gensini score, and the presence or absence of vascular ulcers and/or irregular outlines of coronary stenotic lesions. Apo(a) protein sizes and the pentanucleotide (TTTTA) repeat polymorphism in the 5' control region of the apo(a) gene were analyzed. Multivariate predictors for the number of diseased vessels were, in decreased order of significance, plasma Lp(a) levels, history of smoking, hypertension, diabetes mellitus, and body mass index (BMI). Independent factors associated with the Gensini score were Lp(a) levels, BMI, hypertension, and diabetes mellitus. A negative association of Lp(a) levels with apo(a) protein sizes, and higher Lp(a) levels in those homozygous for an allele with 8 8 (TTTTA)-repeats, was found in both the controls and patients. In decreasing order of significance, apo(a) protein sizes, the degree of atherosclerosis, the genotype of the pentanucleotide repeat, and gender were independent predictors of Lp(a) levels in stepwise regression models. Apo(a) protein sizes were a significant predictor, and the genotype homozygous for the 8 (TTTTA)-repeats was a possible predictor, for the degree of atherosclerosis in CHD. These findings support the notion that a high Lp(a) level is a risk for the development of atherosclerosis in CHD.

Methylenetetrahydrofolate reductase and apolipoprotein E polymorphisms are independent risk factors for coronary heart disease in Japanese: a case-control study.

A missense variant of the C677T (Ala --> Val) polymorphism in the methylenetetrahydrofolate reductase gene (MTHFR) (the T allele) may increase levels of plasma homocysteine. Apolipoprotein E4 increases plasma LDL-cholesterol levels. Increased levels of homocysteine and LDL-cholesterol have been recognized as risk factors for coronary heart disease (CHD). To examine whether the polymorphisms in the MTHFR gene and the APOE gene are associated with CHD in the Japanese, we analyzed 214 CHD patients with an onset age before 65 and 310 apparently healthy persons. In the controls, significantly higher plasma concentrations of homocysteine were observed in the MTHFR TT genotype (15.1+/-6.0 mmol/l) compared with the CT genotype (11.2+/-1.9 mmol/l) and the CC genotype (10.5+/-3.3 mmol/l). The MTHFR TT genotype was significantly more frequent in the CHD patients (28.5%) compared with the control subjects (13.5%); the odds ratio was 2.54 (P < 0.00003). Subjects with the apo E4 allele were significantly more frequent in the CHD group (22.9%) than in the control group (10.0%); the odds ratio was 2.74 (P < 0.00004). Multivariate analysis showed that the TT genotype of MTHFR and the apoE4 allele are independent risk factors for CHD in the Japanese.

A synergistic effect of serotonin transporter gene polymorphism and smoking in association with CHD.

Serotonin induces vasoconstriction in the presence of atherosclerotic lesions. Platelets acquire serotonin from the extracellular space by serotonin transporter and release it following aggregation. There is a functional polymorphism in the serotonin transporter (5-HTT) gene promoter associated with transcriptional efficacy and plasma serotonin levels. To examine whether the polymorphism is associated with coronary heart disease (CHD) in the Japanese, we analyzed 144 male CHD patients with an onset age before 65 and 222 apparently healthy men. The L allele was observed significantly more frequently in the CHD patients (26%) than in the control subjects (19%); the odds ratio was 1.48 (p <0.03). A significant interaction between the polymorphism and smoking was observed for CHD (p = 0.03), suggesting that the two have a synergistic effect on CHD. Odds ratio of the combination of the L allele and smoking was 1.95 (p <0.003). The 5-HTT gene promoter polymorphism may play a role in susceptibility to CHD, particularly when it is combined with smoking.

Candidate genes for atopic asthma: current results from genome screens.

Atopic asthma is one of the most common childhood diseases in developed countries. Asthma is characterized by reversible airway obstruction, bronchial hyper-responsiveness, and airway inflammation. Atopy in childhood is considered the strongest predisposing factor for asthma. The etiology of asthma is complex and is thought to involve the interaction of multiple genes and a variety of environmental factors such as allergens and viral and bacterial infections. To identify genes conferring susceptibility for asthma and atopy, many genome-wide screens for asthma and its associated traits have now been carried out, and genetic linkage has been consistently identified in several regions. Several independent genome-wide screens found regions of linkage with asthma on chromosomes 5, 6, 11, 12, 13, 16 and 19, identifying candidate susceptibility genes including FCER1B, the IL-4 gene cluster, TNFalpha, HLA loci and others. However, the evidence for linkage is still only suggestive for most regions. In an effort to clarify the mechanism underlying the development of asthma, further studies utilizing new technologies and data from the Human Genome Project are ongoing. It is hoped that this accumulation of data will lead to improved genetic testing and assist in the development of new drugs.

Haplotypes of the 5' region of the IL-4 gene and SNPs in the intergene sequence between the IL-4 and IL-13 genes are associated with atopic asthma.

IL-4 and IL-13 are important in IgE synthesis and allergic inflammation. Therefore, genes encoding IL-4 and IL-13 are candidates for predisposition to asthma and atopy. A recent study in the YAC transgenic mouse has revealed that one of the conserved noncoding sequences (CNS-1) between IL-4 and IL-13 influences the expression of IL-4, IL-5, and IL-13, suggesting that CNS-1 acts as a coordinate regulator of these genes. This investigation screened for mutations in the 13-kb region between IL-4 and IL-13, which includes the human equivalent of the murine CNS-1. Four single nucleotide polymorphisms (SNPs) were found in the region between IL-4 and IL-13 (IL-4-IL-13SNP1, IL-4-IL-13SNP2, IL-4-IL-13SNP3, and IL-4-IL-13SNP4). There was no mutation in the human CNS-1. We genotyped these and other previously reported polymorphisms in IL-4 and IL-13 using asthmatic families, and examined association by transmission disequilibrium test. Two-locus haplotype analysis revealed that haplotypes composed of the IL-4 RP2del, IL-4 +33T, or IL-4 -589T alleles and either IL-4-IL-13SNP3G or IL-4-IL-13SNP4C are transmitted significantly to asthma-affected children (p = 0.002). This data suggests that haplotypes composed of the 5' region polymorphisms in the IL-4 gene and SNPs in the intergene sequence between IL-4 and IL-13 influence the development of asthma.

Comparison between the cytogenetic test for fragile X and the molecular analysis of the FMR-1 gene in Japanese mentally retarded individuals.

The prevalence of the fragile X syndrome has been estimated by the results of population studies in which the disease was mostly diagnosed by cytogenetic examinations. To examine the reliability of the cytogenetic analysis for the estimation of the prevalence of the fragile X syndrome, the CGG repeat in the FMR-1 gene was assayed by Southern blot hybridization and polymerase chain reaction (PCR) in an institutionalized group of mentally retarded individuals consisting of 305 males and 129 females. The data thus obtained were compared with the cytogenetic data. The DNA analysis detected 7 full mutations among the alleles of the 296 unrelated males and 2 full mutations among the alleles of the 129 unrelated females. These findings were consistent with the cytogenetic data. No premutation was found in 554 X chromosomes in the unrelated mentally retarded patients nor 826 X chromosomes in unrelated control individuals. The distribution of the CGG repeat number in the normal range was not significantly different between the mentally retarded individuals and the control individuals. These data suggest that the estimates of the prevalence of the fragile X syndrome based on cytogenetic data in the population studies are almost reliable. Based on the finding that no premutations were found in this study, a small difference in the prevalence of the fragile X syndrome between Caucasians and Japanese is suggested.

Mutation and association analysis of the Fyn kinase gene with alcoholism and schizophrenia.

Lack of Fyn tyrosine kinase increases alcohol sensitivity. Fyn phosphorylates a component of the NMDA receptor, which may be involved in schizophrenia. The Fyn gene is located on human chromosome 6q21, to which linkage of schizophrenia has been suggested. We hypothesized that the Fyn gene is a candidate for predisposition to alcoholism and schizophrenia, and we performed a mutation study of the 5'-flanking region, all coding exons, and exon-intron junctions of the Fyn gene. The SSCP mutation analysis was performed in 48 unrelated alcoholics and 16 unrelated schizophrenics. Three polymorphisms, -93A/G in the 5'-flanking region, IVS10+37T/C in intron 10, and Ex12+894T/G in the 3'-untranslated region, were identified. A rare variant of Ex12+1162TG in the 3'-untranslated region was also detected. Neither missense nor nonsense mutations were found. Case-control studies using a larger sample of unrelated patients and controls did not reveal significant associations between these polymorphisms and alcoholism or schizophrenia. In addition, genotyping a microsatellite marker, D6S302, located in intron 10 of the Fyn gene, did not show a significant association between the marker and alcoholism or schizophrenia. Results of the present study did not provide evidence for the involvement of the genomic Fyn gene mutations in alcoholism or schizophrenia. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:716-720, 2000.