The YWHAE gene confers risk to major depressive disorder in the male group of Chinese Han population.

Schizophrenia and major depressive disorder are two major psychiatric illnesses that may share specific genetic risk factors to a certain extent. Increasing evidence suggests that the two disorders might be more closely related than previously considered. To investigate whether YWHAE gene plays a significant role in major depressive disorder in Han Chinese population, we recruited 1135 unrelated major depressive disorder patients (485 males, 650 females) and 989 unrelated controls (296 males, 693 females) of Chinese Han origin. Eleven common SNPs were genotyped using TaqMan® technology. In male-group, the allele and genotype frequencies of rs34041110 differed significantly between patients and control (Pallele=0.036486, OR[95%CI]: 1.249442(1.013988-1.539571); Pgenotype=0.045301). Also in this group, allele and genotype frequencies of rs1532976 differed significantly (Pallele=0.013242, OR[95%CI]: 1.302007(1.056501-1.604563); genotype: P=0.039152). Haplotype-analyses showed that, in male-group, positive association with major depressive disorder was found for the A-A-C-G haplotype of rs3752826-rs2131431-rs1873827-rs12452627 (χ2=20.397, P=6.38E-06, OR[95%CI]: 7.442 [2.691-20.583]), its C-A-C-G haplotype (χ2=19.122, P=1.24E-05, OR and 95%CI: 0.402 [0.264-0.612]), its C-C-T-G haplotype (χ2=9.766, P=0.001785, OR[95%CI]: 5.654 [1.664-19.211]). In female-group, positive association was found for the A-A-C-G haplotype of rs3752826-rs2131431-rs1873827-rs12452627 (χ2=78.628, P=7.94E-19, OR[95%CI]: 50.043 [11.087-225.876]), its A-C-T-G haplotype (χ2=38.806, P=4.83E-10, OR[95%CI]: 0.053 [0.015-0.192]), the C-A-C-G haplotype (χ2=18.930, P=1.37E-05, OR[95%CI]: 0.526 [0.392-0.705]), and the C-C-T-G haplotype (χ2=38.668, P=5.18E-10, OR[95%CI]: 6.130 [3.207-11.716]). Our findings support YWHAE being a risk gene for Major Depressive Disorder in the Han Chinese population.

Association study on the DLG4 gene and schizophrenia in the Chinese Han population.

BACKGROUND: Abnormal expressions of the N-methyl-D-aspartate receptor and its interacting postsynaptic density (PSD) molecules have been hypothesized to be involved in the pathophysiology of schizophrenia. Few studies have carried out association studies with DLG4 gene (coding PSD-95 protein) and sought to validate the results with Asian schizophrenia patients. PATIENTS AND METHODS: To further investigate the significance of DLG4 in Asian schizophrenic patients, we examined seven single-nucleotide polymorphisms (SNPs) within this gene in 1504 unrelated Chinese mainland individuals (893 patients and 611 controls). RESULTS: No association was found between these seven SNPs and schizophrenia within our sample. No significant differences in allele or genotype frequencies between schizophrenic paranoid patients and controls were found. CONCLUSION: Although no allelic or genotypic variances of this gene were observed, the possibility that SNPs within DLG4 represent a positive schizophrenia risk gene cannot be excluded. Our research provided a reference for further research into this gene in other populations.

[Advances of genetics in diabetic nephropathy].

Diabetic nephropathy (DN) is one of the most serious chronic complications of diabetes mellitus. The observed incidence patterns in different ethnics and familial clustering have suggested that the genetic factor plays an important role in the development and progression of DN. This paper reviews the recent advances on genetics of DN, including candidate genes association studies, linkage studies and genome-wide association studies (GWASs). Candidate genes association studies and meta-analysis showed that a few candidate genes have been reproducibly associated with DN, such as ACE, AGT and PPARG genes. Linkage studies and genome-wide linkage studies have also identified susceptibility chromosomal loci. With the development of high-throughput sequencing and chip techniques, GWAS has become an important strategy to identify variants responsible for DN. The genetic factor has been the significant contribution to the pathobiology of DN. However, it is not the only cause of the pathobiology of DN, because the environment factor also influences the pathobiology of DN. Nonetheless, genetic studies may provide valuable information for the pathobiology of nephropathy and potential targets of its treatment.

Polymorphisms and haplotypes in the YWHAE gene increase susceptibility to bipolar disorder in Chinese Han population.

BACKGROUND: Schizophrenia and bipolar disorder are 2 major psychiatric illnesses sharing some specific genetic risk factors. Increasing evidence suggests the 2 illnesses might be more closely related than previously considered. OBJECTIVE: To test this hypothesis, we investigated the allele and genotype frequencies of 11 single nucleotide polymorphisms (SNPs) and the haplotypes in these SNPs of the YWHAE gene. METHOD: 1,982 patients were interviewed by 2 independent, experienced psychiatrists. Bipolar disorder diagnoses were made in strict accordance with Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria using the Structured Clinical Interview for DSM-IV Axis I Disorders. In 2011, we conducted this genetic association analysis between 11 SNPs in YWHAE and bipolar disorder, involving a male group and a female group. RESULTS: In the analysis of allele and genotype frequencies, the SNP rs1873827 increased susceptibility to bipolar disorder in the male group. The haplotype analysis of CAC in rs3752826, rs2131431, and rs1873827 in the male group (χ2 = 25.744, P = 3.97E-07, OR = 0.478 [95% CI, 0.358-0.639]) and of ACT and CAC in rs3752826, rs2131431, and rs1873827 in the female group (for ACT, χ2 = 30.365, P = 3.67E-08, OR = 0.040 [95% CI, 0.007-0.218]; for CAC, χ2 = 16.874, P = 4.04E-05, OR = 0.597 [95% CI, 0.466-0.765]) showed they are protective factors for bipolar disorder. However, the haplotype analysis of CAT in the male group (χ2 = 19.874, P = 8.39E-06, OR = 2.314 [95% CI, 1.587-3.374]) and of AAC and CAT in the female group (for AAC, χ2 = 38.561, P = 5.47E-10, OR = 7.104 [95% CI, 3.471-14.540]; for CAT, χ2 = 25.497, P = 4.52E-07, OR = 2.076 [95% CI, 1.556-2.770]) showed they are risk factors for bipolar disorder. CONCLUSIONS: Considering the size of our sample, the results suggest that YWHAE does play a major role in bipolar disorder in the Han Chinese population.

Association between a COMT polymorphism and clinical response to risperidone treatment: a pharmacogenetic study.

A total of 130 Chinese schizophrenic patients (45 male, 85 female) were enrolled in the study. Clinical efficacy was determined using Brief Psychiatric Rating Scale (BPRS) scores. We genotyped 10 single-nucleotide polymorphisms (SNPs) of the catechol-O-methyl transferase gene (COMT) in our patients and re-examined them for association with changes in BPRS scores after 8 weeks of risperidone monotherapy. COMT is one of the genes that confer susceptibility to schizophrenia, both because of its role in neurotransmitter metabolism and because of its location in the high-risk schizophrenia-related region 22q11. Recent studies also found that COMT functional polymorphisms influenced individual response to antipsychotic medication. Our aim in this study was to explore the influence of COMT polymorphisms on pharmacological response to risperidone in the Chinese population. Statistical analysis revealed a significant association between an upstream COMT SNP, rs9606186, and scores reduction of BPRS in all patients and in the male subgroup but not in the female subgroup (allele analysis: P=0.055 for all, P=0.012 for male patients; genotype analysis: P=0.046 for all, P=0.020 for male patients, uncorrected, odds ratio=3.95). The COMT gene polymorphism, SNP rs9606186, is associated with risperidone therapy efficiency in the Chinese population. This association exhibited a sexually dimorphic difference, which may shed light on the genetics of COMT and its enzymatic sex-dependent mechanism.

No association between the USP7 gene polymorphisms and colorectal cancer in the Chinese Han population.

Colorectal cancer (CRC), now the third most common cancer across the world, is known to aggregate in families. USP7 is a very important protein with an important role in regulating the p53 pathway, which is critical for genomic stability and tumor suppression. We here genotyped eight SNPs within the USP7 gene and conducted a case-control study in 312 CRC patients and 270 healthy subjects in the Chinese Han population. No significant associations were found for any single SNP and CRC risk. Our data eliminate USP7 as a potential candidate gene towards for CRC in the Han Chinese population.

Quantitative assessment of the effect of LRRK2 exonic variants on the risk of Parkinson's disease: a meta-analysis.

Leucine-rich repeat kinase 2 (LRRK2, PARK8) gene has attracted considerable attention since the variants in this gene are recognized as the most common cause of Parkinson's disease (PD) so far. A number of association studies concerning variants of LRRK2 gene and PD susceptibility have been conducted in various populations. However, some results were inconclusive. To derive a more precise estimation of the relationship between LRRK2 and genetic risk of PD, we performed a comprehensive meta-analysis which included 27,363 cases and 29,741 controls from 61 published case-control studies. Totally, the effect of five LRRK2 variants all within the coding regions, i.e. G2019S, G2385R, R1628P, P755L and A419V, were evaluated in the meta-analysis using fixed effect model or random effects model if heterogeneity existed. There were genetic associations between four variants (G2019S, G2385R, R1628P and A419V) and increased PD risk, while there was no evidence of statistically significant association between P755L and PD. Publication bias and heterogeneity were absent in most analyses. Within its limitations, this meta-analysis demonstrated that the G2019S, G2385R, R1628P and A419V variations are risk factors associated with increased PD susceptibility. However, these associations vary in different ethnicities.

Variations in/nearby genes coding for JAZF1, TSPAN8/LGR5 and HHEX-IDE and risk of type 2 diabetes in Han Chinese.

Several genetic loci (JAZF1, CDC123/CAMK1D, TSPAN8/LGR5, ADAMTS9, VEGFA and HHEX-IDE) were identified to be significantly related to the risk of type 2 diabetes and quantitative metabolic traits in European populations. Here, we aimed to evaluate the impacts of these novel loci on type 2 diabetes risk in a population-based case-control study of Han Chinese (1912 cases and 2041 controls). We genotyped 13 single-nucleotide polymorphisms (SNPs) in/near these genes and examined the differences in allele/genotype frequency between cases and controls. We found that both IDE rs11187007 and HHEX rs1111875 were associated with type 2 diabetes risk (for both variants: odds ratio (OR)=1.15, 95% confidence interval (CI) 1.04-1.28, P=0.009). In a meta-analysis where we pooled our data with the three previous studies conducted in East Asians, we found that the variants of JAZF1 rs864745 (1.09 (1.03-1.16); P=3.49 × 10(-3)) and TSPAN8/LGR5 rs7961581 (1.11(1.05-1.17); P=1.89 × 10(-4)) were significantly associated with type 2 diabetes risk. In addition, the meta-analysis (7207 cases and 8260 controls) also showed that HHEX rs1111875 did have effects on type 2 diabetes in Chinese population (OR=1.15(1.10-1.21); P=1.93 × 10(-8)). This large population-based study and meta-analysis further confirmed the modest effects of the JAZF1, TSPAN8/LGR5 and HHEX-IDE loci on type 2 diabetes in Chinese and other East Asians.

HTR2C promoter polymorphisms are associated with risperidone efficacy in Chinese female patients.

AIMS: A number of studies demonstrate that the polymorphisms in the 5 region of HTR2C play a pivotal role in antipsychotic drug efficacy. Since risperidone is an antagonist of HTR2C, polymorphic variations in HTR2C may explain variability in response to risperidone treatment. We analyzed HTR2C polymorphisms for association with efficacy of risperidone monotherapy. MATERIALS & METHODS: We genotyped five SNPs distributed throughout the HTR2C gene and examined them for association using the Brief Psychiatric Rating Scale score in 130 Chinese schizophrenic patients following an 8-week period of risperidone monotherapy. All the patients were receiving the atypical antipsychotic drug treatment for the first time and had a 4-week medication-free period before research began. RESULTS: We found rs518147, rs1023574 and rs9698290 were significantly associated with risperidone treatment in female patients (F = 4.75, degrees of freedom = 2 and p = 0.011; F = 4.329, degrees of freedom = 2 and p = 0.016; F = 4.188, degrees of freedom = 2 and p = 0.019, respectively) and they were also found to be in one linkage disequilibrium block. CONCLUSION: Our results indicate that variants in the HTR2C promoter region are likely to affect the risperidone therapeutic effect in female mainland patients. It may be helpful to investigate a combination of other clinical factors to predict atypical antipsychotic efficacy.

No association between EGR gene family polymorphisms and schizophrenia in the Chinese population.

Early growth response (EGR) genes are thought to have a role in the pathogenesis of schizophrenia because of their conserved DNA binding domain and biologically activity in neuronal plasticity. This zinc-finger motif could influence gene post-translational modification and expression. The multigenetic association model, using markers in genes of similar or antagonistic biological effects within a signal pathway or gene family, might be more appropriate to this aspect of the schizophrenia hypothesis than the single gene strategy. In this study we investigated the role of EGR1, EGR2, EGR3 and EGR4 within the EGR family. Taqman technology was used to examine 12 single nucleotide polymorphisms (SNPs) covering these four genes in 2044 Chinese Han subjects. Case-control analyses were performed to detect association of these 4 genes with schizophrenia and multifactor dimensionality reduction (MDR) analysis was employed to examine their potential gene-gene interaction in schizophrenia. Neither allelic nor genotypic single-locus tests revealed any significant association between EGR1-4 and the risk of schizophrenia nor was any such association found with regard to interaction within EGR1-4 (p(min)=0.623, CV Consistency=10/10). We concluded that although multiple candidate genes are involved in schizophrenogenic development, the EGR family may not play a major role in schizophrenia susceptibility in the Chinese Han population.

Prenatal malnutrition and adult schizophrenia: further evidence from the 1959-1961 Chinese famine.

OBJECTIVE: Evidence from the 1944-1995 Dutch Hunger Winter and the 1959-1961 Chinese famines suggests that those conceived or in early gestation during famines, have a 2-fold increased risk of developing schizophrenia in adult life. We tested the hypothesis in a second Chinese population and also determined whether risk differed between urban and rural areas. METHOD: The risk of schizophrenia was examined in Liuzhou prefecture of Guangxi autonomous region. Rates were compared among those conceived before, during, and after the famine years. Based on the decline in birth rates, we predicted that those born in 1960 and 1961 would have been exposed to the famine during conception or early gestation. All psychiatric case records in Liuzhou psychiatric hospital for the years 1971 through 2001 were examined and clinical/sociodemographic data extracted by psychiatrists blind to exposure status. Data on births and deaths in the famine years were also available, and cumulative mortality was estimated from later demographic surveys. Evidence of famine was verified, and results were adjusted for mortality. Relative risks (RRs) for schizophrenia were calculated for the region as a whole and for urban and rural areas separately. RESULTS: Mortality-adjusted RR for schizophrenia was 1.5 (1960) and 2.05 (1961), respectively. However, the effect was exclusively from the rural areas RR = 1.68 (1960) and RR = 2.25 (1961). CONCLUSIONS: We observe a 2-fold increased risk of schizophrenia among those conceived or in early gestation at the height of famine with risk related to severity of famine conditions.

BDNF gene is a genetic risk factor for schizophrenia and is related to the chlorpromazine-induced extrapyramidal syndrome in the Chinese population.

BACKGROUND: Brain-derived neurotrophic factor (BDNF) belongs to a family of the neurotrophin, which plays important roles in the neurodevelopment of dopaminergic-related systems and interacts with meso-limbic dopaminergic systems involved in the therapeutic response to antipsychotics. Functional experiments have suggested that BDNF may be involved in the etiology of schizophrenia. METHODS AND RESULTS: In this study, we genotyped two important functional polymorphisms in the BDNF gene using a sample of Han Chinese patients consisting of 340 schizophrenic patients and 343 healthy controls. We found a statistical difference in the 232-bp allele distribution of the BDNF gene (GT)n dinucleotide repeat polymorphism between the schizophrenic patients and controls. In early onset patients, the 234-bp allele had a risk role. For the chlorpromazine-induced extrapyramidal syndrome, the 230-bp allele and the 234-bp allele acted in opposite directions, that is, patients with the 230-bp allele of the (GT)n polymorphism exhibited a lower degree of induced extrapyramidal syndrome. Haplotype-based analysis also revealed a very important risk haplotype (P=0.0000226546). CONCLUSION: These findings suggest that BDNF plays an important role in the susceptibility to schizophrenia and that the (GT)n repeat polymorphism of the BDNF gene may be an independent contributor to the chlorpromazine treatment-sensitive form of schizophrenia.

Association study of a (TG)n dinucleotide repeat at chromosome 15q13.3 and schizophrenia in the Chinese population.

Linkage studies have suggested that chromosome 15q13-q14 may harbor a susceptibility locus for schizophrenia. In the current study, the association between a (TG)n dinucleotide repeat polymorphism at D15S976 and schizophrenia was investigated using two independent samples from the Han Chinese population. In a population-based study, no significant difference was found between the genotype and allele frequency distributions in schizophrenia patients and control subjects. In a family-based study, no significant transmission disequilibrium from heterozygous parents to affected offspring was observed. Further analysis of the parent-of-origin effect found nominally significant allele-wise transmission disequilibrium through maternal transmissions, while 157bp and 159bp alleles showed significant individual allelic transmission disequilibrium from heterozygous mothers to affected offspring. Our results did not support the hypothesis that the (TG)n dinucleotide repeat polymorphism plays a major role in schizophrenia susceptibility in the Chinese population. Further studies are needed to elucidate the putative parent-of-origin effect and its role in schizophrenia susceptibility.

[Genetic analysis of a Chinese pedigree with split hand and foot malformation].

OBJECTIVE: To analyze the clinical manefestation and genetic basis of split hand and foot malformation (SHFM) in a Chinese pedigree. METHODS: The affected people in the family were checked by X-rays. Eighteen patients provided their peripheral blood, and the genomic DNA of the samples was extracted. The linkage and haplotype analysis were carried out using the microsatellite markers, and the limb malformation related gene Dactylin (DAC) including the coding region, exon-intron boundaries and part of promoter region was sequenced. RESULTS: Most members of the family with the disease phenotype showed absence or hypoplasia of the index finger, and absence or 3-4 syndactyly of the middle finger. The degree of abnormality in feet was severer than that in hands. All phenotypes of the patients display the basic characters of SHFM. Since the maximum two point LOD score of the D10S192 was 3.50 (theta=0.00), the SHFM in this pedigree can be categorized to the SHFM3. The haplotype analysis of recombination events revealed the candidate locus to a 21cM region between D10S185 and D10S1693. No mutation was found by the sequencing result of DAC gene. CONCLUSION: Through the analysis of phenotype of the patients, the typical SHFM disease can be confirmed. The linkage and haplotype analysis demonstrated that the 21cM region in 10q23-q26 locus was the major cause to the disease in this pedigree. The mutation of DAC gene can be excluded from cause of SHFM3 phenotype.

[Association study of an (AC)n dinucleotide repeat and schizophrenia in Asian and European populations].

Linkage studies have suggested that chromosome 15q13-q14 may harbor a susceptibility locus for schizophrenia. In the current study, the association between a (AC)n dinucleotide repeat polymorphism at D15S118 and schizophrenia was investigated using three independent samples from the Han Chinese population and the Scotland population. In the population-based study, a significant difference was found between the allele frequency distributions in schizophrenia patients and control subjects in the Scottish samples (P = 0.04), but was not replicated in the Chinese samples. In a family-based study, no significant transmission disequilibrium from heterozygous parents to affected offspring was observed. Overall, our results did not support the hypothesis that the (AC)n dinucleotide repeat polymorphism plays a major role in schizophrenia susceptibility, at least in the Chinese population. Further studies are needed to elucidate its role in schizophrenia susceptibility in European population.

Association of AKT1 gene polymorphisms with risk of schizophrenia and with response to antipsychotics in the Chinese population.

BACKGROUND: A number of studies have pointed to the involvement of AKT signaling pathways in the etiology of schizophrenia. The purpose of this study was to determine whether the AKT1 gene is involved in the etiology of schizophrenia and whether it affects therapeutic outcomes in the Chinese population. METHOD: Five single nucleotide polymorphisms (SNPs) were genotyped among 384 schizophrenic patients (DSM-IV criteria) and 384 healthy controls from the Chinese population. We systematically analyzed the association of the AKT1 gene with schizophrenia on the basis of sex, age at onset, therapeutic response to typical antipsychotics and atypical antipsychotics, and presence or absence of extrapyramidal syndrome. The study was conducted from May 2004 to June 2006. RESULTS: We found a positive association of the G allele of the SNP marker rs3803300 with schizophrenia (p = .003), both in early-onset and late-onset subjects, and that a haplotype A-G-C-G-A constructed by the 5 SNPs showed significant association (p = .00004886). However, we found no relationship between any of the 5 SNP markers and therapeutic response to typical and atypical antipsychotics and chlorpromazine-induced extrapyramidal syndrome. CONCLUSIONS: Our study suggests that AKT1 is a susceptibility gene for schizophrenia in the Chinese population and that the AKT1 gene may play no major role in the therapeutic response to antipsychotics or in chlorpromazine-induced extrapyramidal syndrome.

Serum prolactin levels, plasma risperidone levels, polymorphism of cytochrome P450 2D6 and clinical response in patients with schizophrenia.

The object of this study is to assess 1) the relationship between plasma antipsychotic drug concentration, serum prolactin levels and the clinical efficacy of risperidone, 2) the relationship between the CYP2D6 polymorphisms and metabolizing of risperidone and 3) the role of 9-hydroxyrisperidone in elevating prolactin levels. One-hundred and eighteen Chinese schizophrenia patients (40 males, 78 females, age 15-60 years) were given risperidone at dosages ranging from 2-8 mg/day for 8 weeks. Clinical efficacy was determined using the Brief Psychiatric Rating Scores (BPRS). Serum prolactin levels were assayed before and after the 8 week treatment and plasma risperidone and 9-hydroxyrisperidone levels were also measured at the end of the 8-week treatment. The results showed there was no significant correlation between the concentration of active moiety and clinical response. Risperidone treatment significantly increased serum prolactin levels. Furthermore, changes of prolactin levels were not correlated with the clinical response. For the risperidone/ 9-hydroxyrisperidone ratio, there was a statistically significant difference among the CYP2D6*1/*1, *1/*10, *10/*10 genotypes (Kruskal-Wallis test, p = 0.012). No significant differences were found in the concentration of 9-hydroxyrisperidone and active moiety among the genotypes. In addition, the concentration of 9-hydroxyrisperidone was not significantly correlated with the increase of serum prolactin. In conclusion, our study has, for the first time, produced evidence that in Chinese schizophrenic patients, the metabolism of risperidone is dependent on CYP2D6. Neither changes in serum prolactin levels nor plasma concentration of active moiety were significantly correlated with clinical efficacy of risperidone. 9-hydroxyrisperidone may not play a predominant role in elevating serum prolactin level.

An association study between PPP1R1B gene and schizophrenia in the Chinese population.

Schizophrenia has been linked with dysfunctions of glutamatergic, dopaminergic, and serotonergic neurotransmission. Dopamine- and cAMP-regulated phosphoprotein of relative molecular mass 32 kDa (DARPP-32), encoded by PPP1R1B (protein phosphatase 1, regulatory/inhibitor subunit 1B) gene, is enriched in neostriatal medium spiny neurons. It plays a key regulator role in dopaminergic and glutamatergic signaling pathways. The combined evidence from reduced DARPP-32 expression in the dorsolateral prefrontal cortex (DLPFC) in schizophrenic patients and from abnormalities in mice with a genetic deletion of DARPP-32 or with point mutations in phosphorylation sites of DARPP-32 suggested that it would be worthwhile to investigate the association between DARPP-32 and schizophrenia. In the present study, we genotyped five single nucleotide polymorphisms (SNPs) in the PPP1R1B gene and conducted a case-control study involving 520 schizophrenic patients and 386 healthy subjects drawn from the Chinese population. No allelic, genotypic or haplotypic association was found. However, our results do not preclude the possibility that the PPP1R1B is a susceptibility gene for schizophrenia in the Chinese population, since, as a central molecular switch, PPP1R1B may contribute to schizophrenia by interacting with other genes. Further functional analysis and genetic association studies are needed to determine the potential roles of PPP1R1B and other related genes in the pathophysiology of schizophrenia.

A case-control association study between the GRID1 gene and schizophrenia in the Chinese Northern Han population.

The glutamatergic dysfunction hypothesis of schizophrenia implicates the genes involved in glutamatergic transmission as strong candidates for schizophrenia-susceptibility. Recent linkage and association studies have identified the glutamate receptor, ionotropic, delta 1 gene GRID1 on 10q22 as a strong candidate for schizophrenia. In this current association study, we genotyped five genetic variants within the GRID1 gene in 567 Chinese Han subjects recruited from Northeast of China (260 schizophrenics and 307 normal controls). Four SNPs, rs1902666 (P=0.024), rs2814351 (P=0.027), rs11591408 (P=0.0000107) and rs999383 (P=0.000093) were found to be significantly associated with schizophrenia. Haplotype analysis also revealed significance with global P values of 0.0081 and 0.00076 for SNPs 1-2 and SNPs 3-4-5 haplotypes, respectively. Our results strongly support previously reported association studies, implicating GRID1 in the etiology of schizophrenia.