Schizophrenia In Chinese Han Population Research Articles

Polymorphism of rs12294045 in EAAT2 gene is potentially associated with schizophrenia in Chinese Han population

BackgroundRecent studies have shown that the excitatory amino acid transporters (EAATs) are associated with schizophrenia. The aim of this study was to investigate the relationship between the polymorphism of EAAT1 and EAAT2 genes and schizophrenia in Chinese Han population.MethodsA total of 233 patients with schizophrenia and 342 healthy controls were enrolled. Two SNPs in EAAT1 gene (rs2269272, rs2731880) and four SNPs in EAAT2 gene (rs12360706, rs3088168, rs12294045, rs10836387) were genotyped by SNaPshot. Clinical features were collected using a self-made questionnaire. Psychotic symptoms of patients were measured by the Positive and Negative Syndrome Scale (PANSS), and patients’ cognitive function was assessed by Matrics Consensus Cognitive Battery (MCCB).ResultsSignificant difference in allelic distributions between cases and controls was confirmed at locus rs12294045 (Ρ = 0.004) of EAAT2 gene. Different genotypes of rs12294045 were associated with family history (P = 0.046), in which patients with CT genotype had higher proportion of family history of psychosis. The polymorphism of rs12294045 was related to working operational memory (LNS: P = 0.016) and verbal learning function (HVLT-R: P = 0.042) in patients in which CT genotype had lower scores. However, these differences were no longer significant after Bonferroni correction.ConclusionsOur study showed that the polymorphism of rs12294045 in EAAT2 gene may be associated with schizophrenia in Chinese Han population. CT genotype may be one of the risk factors for family history and cognitive deficits of patients.

Association of nitric oxide synthase 1 adaptor protein gene polymorphisms with schizophrenia in a Chinese Han population.

Introduction:Previous studies have analyzed the association between nitric oxide synthase 1 adaptor protein (NOS1AP) polymorphisms and schizophrenia; however, the results were inconsistent and there was a lack of evidence in a larger sample of Chinese Han population.Subjects and Methods:We decided to determine the association between four NOS1AP single-nucleotide polymorphisms (i.e., rs1858232A/G, rs4531275C/T, rs4657178C/T, and rs6704393C/T) and schizophrenia in northern Chinese Han population (350 patients and 522 controls) using restriction fragment length polymorphism.Results:Between schizophrenia group and healthy group, the genotype and allele frequencies for rs1858232A/G differed significantly (χ2 = 6.256, 4.145; P = 0.044, 0.045), but neither genotype nor allele frequencies of rs4531275C/T differed significantly. The genotype frequencies for rs4657178C/T and rs6704393C/T differed significantly (χ2 = 19.782, 12.683; P < 0.01, P = 0.002) between schizophrenia group and healthy group. In the gender-specific analysis, we found statistically significant difference in genotype frequencies between patients and controls in both subgroups for rs4657178C/T (χ2 = 9.356, 9.585; P = 0.009, 0.008). There was also a significant difference in the genotype frequency between patients and controls in male subgroup for rs6704393C/T (χ2 = 8.800, P = 0.012). In the haplotype analysis, only the TCT haplotype frequency of rs6704393C/T, rs4531275C/T, and rs4657178C/T differed significantly between patients and controls in total population (χ2 = 5.215, P = 0.022).In conclusion:Individuals with G allele of rs1858232A/G and C allele of rs4657178C/T which may be risk factors for schizophrenia should be given more attention, and also to individuals with the TCT haplotype, who are more likely to have schizophrenia. These results provide novel evidence for an association between NOS1AP polymorphisms and schizophrenia.

Glutathione S-transferase gene polymorphisms (GSTT1 and GSTM1) and risk of schizophrenia: A case-control study in Chinese Han population.

Schizophrenia (SCZ) is a chronic disability disorder related to oxidative stress. Glutathione S-transferase (GST) is a group enzyme that protects cells and tissues from oxidative stress damage. Among GSTs, GSTT1 and GSTM1 have well defined genetic polymorphisms. The purpose of our research was to explore the correlation between GSTT1 and GSTM1 polymorphism and SCZ risk in Chinese Han population.A total of 650 subjects (386 SCZ patients and 264 healthy individuals) were included in this case–control designed study. The GSTT1 and GSTM1 polymorphisms were analyzed by multiplex polymerase chain reaction (PCR). We explored the relationship between these 2 polymorphisms and the risk of SCZ.We found that the GSTT1 null genotype had a protective effect on the development of SCZ [odds ratio (OR) = 0.601, 95% confidence interval (95% CI) = 0.412–0.986, P = .031]. We also found that the combination of null genotypes of the GSTT1 and GSTM1 genes was made at a lower risk of SCZ (OR = 0.452, 95% CI = 0.238–0.845, P = .028). However, we found no correction between Positive and Negative Syndrome Scale score (PANSS) and GSTM1, GSST1 genotypes in SCZ patients.Our finding revealed that GSTT1 null polymorphisms may be related to the reduced risk of SCZ in Chinese Han population, and this risk was further reduced with the combination of GSTT1 null polymorphisms and GSTM1 null polymorphisms.

Association analysis of single nucleotide polymorphisms in the promoter region of GAD1 and GABRB3 with schizophrenia in Chinese Han population

Association analysis of single nucleotide polymorphisms in the promoter region of GAD1 and GABRB3 with schizophrenia in Chinese Han population

Association of the CACNA2D2 gene with schizophrenia in Chinese Han population.

BackgroundSchizophrenia (SCZ) is a severely complex psychiatric disorder in which ~80% can be explained by genetic factors. Single nucleotide polymorphisms (SNPs) in calcium channel genes are potential genetic risk factors for a spectrum of psychiatric disorders including SCZ. This study evaluated the association between SNPs in the voltage-gated calcium channel auxiliary subunit alpha2delta 2 gene (CACNA2D2) and SCZ in the Han Chinese population of Northeast China.MethodsA total of 761 SCZ patients and 775 healthy controls were involved in this case-control study. Three SNPs (rs3806706, rs45536634 and rs12496815) of CACNA2D2 were genotyped by the MALDI-TOF-MS technology. Genotype distribution and allele frequency differences between cases and controls were tested by Chi-square (χ2) in males and females respectively using SPSS 24.0 software. Linkage disequilibrium and haplotype analyses were conducted using Haploview4.2. The false discovery rate correction was utilized to control for Type I error by R3.2.3.ResultsThere was a significant difference in allele frequencies (χ2 = 9.545, Padj = 0.006) and genotype distributions (χ2 = 9.275, Padj = 0.006) of rs45536634 between female SCZ patients and female healthy controls after adjusting for multiple comparisons. Minor allele A (OR = 1.871, 95% CI [1.251–2.798]) and genotype GA + AA (OR = 1.931, 95% CI [1.259–2.963]) were associated with an increased risk of SCZ. Subjects with haplotype AG consisting of rs45536634 and rs12496815 alleles had a higher risk of SCZ (OR = 1.91, 95% CI [1.26–2.90]) compared those with other haplotypes.ConclusionsThis study provides evidence that CACNA2D2 polymorphisms may influence the susceptibility to SCZ in Han Chinese women.

Association Between Glutathione S-Transferase (GST) Polymorphisms and Schizophrenia in a Chinese Han Population.

BackgroundGlutathione S-transferase (GST) is an important antioxidant enzyme in the body. The weakening of the antioxidant system causes damage to the cells and tissues that make up the organism, adversely affects the function of the nervous system, and ultimately leads to schizophrenia (SCZ). Previous studies have yielded inconsistent results across different ethnic populations.PurposeThis case–control study was carried out to investigate whether genetic polymorphisms in GST could be associated with SCZ in the Chinese Han population.Patients and MethodsA total of 794 participants, including 379 SCZ patients (case group) and 415 healthy individuals (control group), were genotyped by polymerase chain reaction-restriction fragment length for polymorphisms in GST genes.ResultsThe study found that the frequency of the GSTM1 null genotype was higher in case group than control group (p=0.003). The frequency of the GSTM1 and GSTT1 double null genotype was also higher in case group than control group (p=0.008).ConclusionWe conclude that the GSTM1 null genotype and the GSTM1 and GSTT1 double null genotype may be related to the onset of SCZ in Chinese Han population.

Effects of GSTA1 and GPX3 Polymorphisms on the Risk of Schizophrenia in Chinese Han Population.

PurposeSeveral lines of evidence support the fact that the presence of oxidative stress plays an important role in the pathophysiological mechanisms of schizophrenia (SCZ). The glutathione peroxidases (GPXs) and glutathione S-transferases (GSTs) are the major antioxidant enzymes. Polymorphic variants of GPX and GST can affect the antioxidant activities of their encoded enzymes. This study explored the possible associations of the GSTA1 and GPX3 gene polymorphisms and schizophrenia in Chinese Han population.MethodsDNA from 648 healthy controls and 617 schizophrenic patients was genotyped for single-nucleotide polymorphisms (SNPs) rs3957357 in GSTA1 and rs736775 in GPX3 using a PCR-LDR genotyping assay. The χ2 test compared differences in genetic distributions between the two groups in a case–control study. The generalized multifactor dimensionality reduction (GMDR) was used to explore the interaction between the GSTA1 gene and the GPX3 gene on the risk of SCZ.ResultsSignificant differences in allelic and genotypic frequencies of GSTA1 rs3957357 were present between SCZ and control groups (GSTA1 rs3957357 χ2=6.172, P=0.046 by genotype, χ2=5.847, P=0.016, odds ratio=1.329, 95% confidence interval=1.055–1.674 by allele). No significant differences in allelic or genotypic frequencies of GPX3 rs736775 were detected between cases and controls (GPX3 rs736775: χ2=2.058, P=0.357 by genotype, χ2=1.853, P=0.173, odds ratio=1.131, 95% confidence interval=0.953–1.342 by allele). Moreover, the GMDR model showed that the interaction between GSTA1 rs3957357 and GPX3 rs736775 was associated significantly with SCZ risk, P=0.0107.ConclusionOur results suggest that GSTA1 rs3957357 SNP has an effect on the risk of SCZ and the interaction between GSTA1 rs3957357and GPX3 rs736775 may affect the development of SCZ in Chinese Han population. However, these results should be validated by replication in different populations with large sample sizes.

TP53 Polymorphism Contributes to the Susceptibility to Bipolar Disorder but Not to Schizophrenia in the Chinese Han Population.

TP53 has been reported to be involved in diverse neurological processes related to the pathogenesis of psychosis. In this study, we aim to determine the association of TP53 polymorphisms, rs1042522 and rs17879353, with the susceptibility to schizophrenia (SCZ) or bipolar disorder (BD) in Chinese Han population. A total of 548 SCZ patients, 512 BD patients, and 598 healthy controls were recruited. Genotyping was conducted through Sequenom MassARRAY technology platform. The quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect TP53 expression level. Results revealed that the allele frequency and genotype distribution of rs1042522 within BD patients were significantly different from those of the controls. Rs1042522 was significantly associated with BD risk under diverse genetic models. However, no significant association was found for rs17879353 and BD risk and for rs1042522 and rs17879353 and SCZ risk. TP53 expression was significantly increased in SCZ patients and BD patients compared with that in the controls but was significantly decreased in BD patients with CC genotype of rs1042522 compared with that in other BD patients with either CG or GG genotype. In summary, we observed for the first time that rs1042522 is significantly associated with BD risk in the Chinese Han population. The increased TP53 expression might affect the occurrence of BD and SCZ, and rs1042522 might affect the progress of BD by disturbing gene expression.

Association of polymorphisms of NAPE-PLD and FAAH genes with schizophrenia in Chinese Han population

To assess the association of polymorphisms of N-acyl-phosphatidylethanolamine-phospholipase D (DAPE-PLD) and fatty acid amide hydrolase (FAAH) genes, as well as their interaction, with schizophrenia. Polymorphisms of NAPE-PLD rs12540583 and FAAH rs324420, rs2295633, and rs6429600 were determined with PCR - restriction fragment length polymorphism assay and Sanger sequencing. The genotypes of 345 subjects of Han Chinese origin diagnosed with schizophrenia and a 403 controls were compared. The results were analyzed with SPSS 17.0, and the interaction of the two genes was analyzed using a multifactor dimensionality reduction (MDR) method. The frequency of NAPE-PLD rs12540583 polymorphism was significantly different between the two groups under both dominant and additive models (χ2=17.18 vs. χ2=18.94, P<0.0125). The frequencies of AC genotype and C allele of the patient group at rs12540583 were higher than those of the controls, and the interaction of NAPE-PLD and FAAH was associated with schizophrenia. A four-loci model (rs12540583, rs324420, rs2295633 and rs6429600) can best model the interaction between NAPE-PLD and FAAH. The AC genotype and C allele of NAPE-PLD rs12540583 locus are risk factors for schizophrenia, and the interaction between NAPE-PLD rs12540583 and FAAH rs324420, rs2295633 and rs6429600 is associated with schizophrenia.

Association study between T-182C and G1287A polymorphisms in norepinephrine transporter gene and schizophrenia

Objective To explore whether the norepinephrine transporter(NET) gene T-182C and G1287A polymorphisms are involved in the etiology of schizophrenics among the Chinese Han population. Methods 249 schizophrenics(case group) and 309 healthy physical examiners(control group) of the Chinese Han population were collected.Ligase detection reaction was used to detect the genotype distributions and allele frequencies of NET rs2242446 and rs5569 polymorphisms in the two groups.The genotype distributions and allele frequencies of these two single nucleotide polymorphisms(SNPs) were also compared in the case and control groups. Results In the case group, the TT genotype of the NET gene loci rs2242446 was the most, 48.6%, and the CC genotype of which was the least, 8.4%.In the control group, the CT genotype was the most, 47.9%, and the CC genotype was the least, 11.3%, the minimum allele frequency was 29.9%.In the case group, the GG genotype of the NET gene loci rs5569 was the most, 46.2%, and the CC genotype was the least, 9.6%.In the control group, GG genotype was the most, 51.5%, and the AA genotype was the least, 10.3%, and the minimum allele frequency was 29.4%.No significant differences in the genotype and allele distribution of NET rs2242446 and rs5569 were found in Chinese-Han patients with schizophrenia and control participants(all P>0.05). In gender-specific analyses, similarly, no significant differences were found for rs2242446 and rs5569 genotype and allele distributions in either the male or the female case-control comparisons(all P>0.05). Conclusion The NET rs2242446 and rs5569 polymorphisms are not associated with schizophrenia in Chinese Han population. Key words: Norepinephrine transporter gene; Single nucleotide polymorphism; Schizophrenia

The interaction of NOS1AP, DISC1, DAOA, and GSK3B confers susceptibility of early-onset schizophrenia in Chinese Han population

Although many major breakthrough had identificated potential susceptibility genes for schizophrenia, the aetiology of schizophrenia is still unknown. In the present study, we focused on the N-methyl-Daspartate receptors related genes nitric oxide synthase 1 adaptor gene (NOS1AP), disrupted in schizophrenia 1 gene (DISC1), d-amino acid oxidase activator gene (DAOA), and glycogen synthase kinase 3-beta gene (GSK3B). A family-based genetic association study (459 Han Chinese subjects in 153 nuclear families) using 3 single nucleotide polymorphisms in NOS1AP, 2 in DISC1, 1 in DAOA and 1 in GSK3B was conducted. We found rs12742393 have just positive trend with schizophrenia (SCZ) (p=0.07) after FDR correction. NOS1AP mRNA and serum levels were significantly elevated in SCZ patients (p<0.001; p<0.001) compared with healthy control. However, expression Quantitative Trait Loci (eQTL) analysis have demonstrated that rs12742393 genotype were not significantly associated with the NOS1AP mRNA expression. GMDR identified a significant seven-locus interaction model involving (NOS1AP-rs348624, rs12742393, rs1415263, DISC1-rs821633, rs1000731, DAOA-rs2391191and GSK3B- rs6438552) with a good testing accuracy (0.72). Our finding suggested statistically significant role of interaction of NOS1AP, DISC1, DAOA, and GSK3B polymorphisms (NOS1AP-rs348624, rs12742393, rs1415263, DISC1-rs821633, rs1000731, DAOA-rs2391191and GSK3B-rs6438552) in EOS susceptibility.

Association between NAT2 polymorphisms and the risk of schizophrenia in a Northern Chinese Han population.

The gene that encodes N-acetyltransferase 2 (NAT2), an enzyme that plays a crucial role in the metabolism of many drugs and xenobiotics, is located on chromosome 8p22, one of the most convictive susceptibility loci of schizophrenia. NAT2 genetic polymorphisms lead to various enzyme acetylation phenotypes. In the present study, six selected NAT2 exonic single nucleotide polymorphisms were genotyped in an independent case-control sample of a Northern Chinese Han population to verify the possible association between NAT2 and schizophrenia. Three (rs1801280T/341C, rs1799930/G590A, and rs1208/A803G) of the six single nucleotide polymorphisms showed significant allele frequency differences between the case and the control groups after rigorous Bonferroni correction. One protective fast-acetylation haplotype (NAT2*4) and two risk slow acetylation haplotypes (NAT2*5B and NAT2*6A) were discovered to be associated with schizophrenia. Our results indicate that NAT2 may be a susceptibility gene for schizophrenia in this Chinese Han population, and the risk haplotypes might cause the impairment of NAT2 in metabolizing neurotoxic substances.

Evidence for Association of Cell Adhesion Molecules Pathway and NLGN1 Polymorphisms with Schizophrenia in Chinese Han Population.

Multiple risk variants of schizophrenia have been identified by Genome-wide association studies (GWAS). As a complement for GWAS, previous pathway-based analysis has indicated that cell adhesion molecules (CAMs) pathway might be involved in the pathogenesis of schizophrenia. However, less replication studies have been reported. Our objective was to investigate the association between CAMs pathway and schizophrenia in the Chinese Han population. We first performed a pathway analysis utilizing our previous GWAS data. The CAMs pathway (hsa04514) was significantly associated with schizophrenia using hybrid gene set-based test (P = 1.03×10−10) and hypergeometric test (P = 5.04×10−6). Moreover, 12 genes (HLA-A, HLA-C, HLA-DOB, HLA-DPB1, HLA-DQA2, HLA-DRB1, MPZ, CD276, NLGN1, NRCAM, CLDN1 and ICAM3) were modestly significantly associated with schizophrenia (P<0.01). Then, we selected one promising gene neuroligin 1 (NLGN1) to further investigate the association between eight significant SNPs and schizophrenia in an independent sample (1814 schizophrenia cases and 1487 healthy controls). Our study showed that seven SNPs of NLGN1 and two haplotype blocks were significantly associated with schizophrenia. This association was confirmed by the results of combined analysis. Among them, SNP rs9835385 had the most significant association with schizophrenia (P = 2.83×10−7). Furthermore, in silico analysis we demonstrated that NLGN1 is preferentially expressed in human brain and SNP rs1488547 was related to the expression level. We validated the association of CAMs pathway with schizophrenia in pathway-level and identified one susceptibility gene NLGN1. Further investigation of the roles of CAMs pathway in the pathogenesis of schizophrenia is warranted.

-141C insertion/deletion polymorphism of the dopamine D2 receptor gene is associated with schizophrenia in Chinese Han population: Evidence from an ethnic group-specific meta-analysis.

Accumulate evidence has implicated dopamine D2 receptor gene polymorphisms in the etiology of schizophrenia. A single nucleotide polymorphism, -141C insertion/deletion (Ins/Del) (rs1799732), in the promoter region of the dopamine D2 receptor gene has been linked to schizophrenia; however, the data are inconclusive. This study investigated whether the -141C polymorphism is associated with the risk of schizophrenia in different ethnic groups by performing a meta-analysis. A total of 24 case-control studies examining the association between -141C Ins/Del polymorphism and schizophrenia were identified according to established inclusion criteria. Significant association was revealed between -141C Ins/Del polymorphism and schizophrenia risk in dominant genetic model (Ins/Ins + Ins/Del versus Del/Del) (odds ratio = 0.33, 95% confidence interval = 0.14-0.81, z = 2.41, P = 0.02) in Chinese Han but not in Caucasian, Japanese or India populations. Our results indicate that -141C Ins/Del polymorphism might be a susceptibility factor for schizophrenia in Chinese Han population.

Association study of GRM7 polymorphisms and schizophrenia in the Chinese Han population

Schizophrenia is a severe and complex mental disorder with high heritability. There is an evidence that metabotropic glutamate receptors (GRM) are associated with schizophrenia. GRM7 has been identified as a candidate gene for many psychiatric disorders especially schizophrenia. In this study, we investigated whether single nucleotide polymorphisms (SNPs) in GRM7 were associated with schizophrenia. Four SNPs (rs9814881, rs13353402, rs9870680 and rs1531939) were genotyped in 1034 schizophrenic patients and 1034 healthy controls of Chinese Han origin. The results showed that the two SNPs rs13353402 and rs1531939 demonstrated significant difference between schizophrenic patients and control subjects in allele frequencies (rs13353402: P value=0.0307, rs1531939: P value=0.0328, respectively). Nevertheless, there was no significant discrepancies in genotype distribution. In summary, our results indicate that the GRM7 SNPs rs13353402 and rs1531939 might be associated with schizophrenia in Chinese Han population.

Association study of the gene MeCP2 polymorphisms with schizophrenia in female

Objective To explore the association of methyl-CpG-binding protein2(MeCP2) polymorphisms with female schizophrenia in Chinese Han population. Methods By using the technology based on micro-array Chip, gene polymorphism analysis of 4 locus located in the gene MeCP2 was performed in 126 schizophrenia patients fulfilled with DSM-Ⅳ-TR criteria for schizophrenia and in 144 healthy controls.Chi square test was used to compare the inter-group differences of genotypic and allelic distribution. Haplotype case-control association analysis based on linkage disequilibrium was conducted using SNP stats online software after the data was screened .The significance of results was corrected by permutation test . Results To the point of Locus rs1616369 which located in Gene MeCP2, the distribution of the genotype G/A between two groups(24.8% vs 34.3%) reached significance (P<0.05); rs3027933, genotype G/C(25.6% vs 34.8%), P<0.05; rs17435, genotype T/A(25.6% vs 35.5%), P<0.05; rs2239464, genotype C/A(58.5% vs 71.8%), P<0.05. The distribution prevalence of Haplotype GCCA was 0.1581 in case group, and 0.2389 in control group, reached significant difference(P<0.05). Conclusion As to female MeCP2 gene, the genotype on the four locations might associate with the onset of schizophrenia, MeCP2 might be susceptibility gene of female schizophrenia. The Haplotype GCCA maybe the protective factor. Key words: MeCP2 gene; Polymorphism; Female; Schizophrenia; Association study

Lack of association of SLC1A1 variants with schizophrenia in Chinese Han population

In this study, we analyzed four single nucleotide polymorphisms (SNPs) (rs10491734, rs2228622, rs301430 and rs301443) of the solute carrier family 1 gene (SLC1A1) in a set of 616 schizophrenia patients and 638 matched healthy controls of Han Chinese descent. No significant differences of genotype or allele distribution were identified between the patients and controls. Our data suggest that SLC1A1 is unlikely to be a major susceptibility gene for schizophrenia in Han Chinese.

Myosin Vb gene is associated with schizophrenia in Chinese Han population

Myosin Vb (MYO5B) has recently been implicated in the etiology of bipolar disorder in a genome-wide association study (GWAS). This gene is involved in amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor subunit glutamate receptor 1 (GluR1) recycling and plays an important role in the primary excitatory neurotransmission. Dysfunction of the brain glutamate system has been postulated to be involved in the pathophysiology in schizophrenia. To further investigate the association between MYO5B polymorphisms and schizophrenia, we genotyped nine single nucleotide polymorphisms (SNPs) in an independent sample of 1463 individuals with schizophrenia and 1563 healthy control subjects, and detected three SNPs and two haplotype blocks which displayed significant association with schizophrenia. This association was further strengthened by the results of meta-analysis. Our data strongly supported that the MYO5B gene might be associated with schizophrenia in the Chinese Han population and they have implications for understanding the glutamate hypothesis of schizophrenia.

2085 – BDNF Val66Met polymorphism and anxiety/depression symptoms in schizophrenia in chinese han population

Background Although several lines of evidences suggest that the BDNF Val66Met polymorphism may be involved in the pathophysiology of schizophrenia, this association remains controversial. Here, we aim to investigate the genetic association between the BDNF Val66Met polymorphism and schizophrenia and to explore whether this polymorphism could influence the severity of clinical symptoms in schizophrenia patients in a Chinese Han population. Methods Genotyping of BDNF Val66Met polymorphism was carried out in 456 schizophrenia patients and 483 controls by the fluorescence resonance energy transfer method (FRET). The patients’ psychotic symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS). The general clinical data of schizophrenia patients were analyzed. Results There were significant differences in the genotype distribution and allelic frequencies of the BDNF Val66Met polymorphism between the schizophrenia group and normal control. Multiple linear regression analysis revealed that the BDNF Val66Met polymorphism explained approximately 16% for the variance of anxiety/depression symptoms in schizophrenia patients. Conclusion Our data provides evidence that the BDNF Val66Met polymorphism may be involved in the etiology of schizophrenia in Chinese Han population. Furthermore, the BDNF Val66Met polymorphism is a significant influencing factor on the severity of anxiety/depression symptoms in schizophrenia patients.

Effect of SOX10 gene polymorphism on early onset schizophrenia in Chinese Han population

Schizophrenia is one of highly heritable psychiatric disorders. Patients with early onset schizophrenia tend to have a greater genetic loading and may be an attractive subpopulation for genetics studies. A single nucleotide polymorphism (SNP) rs139887 in sex-determining region Y-box 10 (SOX10), a candidate gene for schizophrenia, was suggested to be associated with schizophrenia although inconsistent results had been reported. The aim of this study was to evaluate the association between SOX10 rs139887 polymorphism and schizophrenia using an early onset sample in the Chinese Han population. A total of 321 schizophrenic patients with onset before age 18 and 400 healthy controls were recruited for association study. In addition, two populations involved in three studies were selected for meta-analysis to determine the effect of rs139887 on schizophrenia. Our association study results showed that the allele and genotype frequencies were significantly different between schizophrenic patients and controls (P=0.013 and P=0.034, respectively). Interestingly, a significant association in allele and genotype frequencies were found in male patients (P=0.017 and P=0.045, respectively), but not female patients. Moreover, the C/C genotype had a significant association with an earlier age of onset in male schizophrenic patients (Kaplan–Meier log-rank test P=0.029), but not in female patients (Kaplan–Meier log-rank test P=0.876). The meta-analysis result showed the same C allele was significantly associated with schizophrenia (P=0.007). In conclusion, the SOX10 rs139887 polymorphism was related to the development of schizophrenia in a gender-specific manner, and may be a significant genetic marker for managing subgroups and etiological clues in schizophrenia.