Association Study Between TGM2Gene And Schizophrenia In Chinese Han Population

Objective: The several lines of evidence have suggested an interesting link betweengluten ingestion and schizophrenia. The increased levels of gliadin antibodies havebeen observed in the patients with schizophrenia. Tissue transglutaminase(transglutaminase2, TGM2) is involved in the production of gliadin antibodies. Toinvestigate genetic association of TGM2gene with schizophrenia, we detected4single nucleotide polymorphisms (SNPs) present in the gene with schizophrenia in aChinese Han population.Methods: Genomic DNA was isolated from the whole blood samples. The method ofPCR-based restriction fragment length polymorphism (PCR-RFLP) was used toexamine the genotypes of the rs2076380, rs7270785, rs4811528and rs6023526loci.The Hardy-Weinberg equilibrium for genotypic distribution was estimated by thegoodness-of-fit χ2test. The frequencies of alleles and genotypes of TGM2gene werestatistically computed.Results: The genotypic distributions of rs2076380, rs7270785, rs4811528andrs6023526were not deviated from the Hardy-Weinberg equilibrium (P>0.05). Therewere no significant differences in the allelic frequencies of TGM2gene between thepatients and the controls (rs2076380：χ2=0.831, P>0.05; rs7270785: χ2=0.591, P>0.05; rs4811528: χ2=0.296, P>0.05; rs6023526: χ2=0.092，P>0.05), and thefrequency distributions of haplotypes had no significant differences between thepatients and the controls (rs2076380: χ2=1.951, P>0.05; rs7270785: χ2=1.399, P>0.05; rs4811528: χ2=0.313, P>0.05; rs6023526: χ2=0.701, P>0.05). In malesample, there were2haplotypes in association with chronic schizophrenia, includingrs4811528(G)-rs6023527(C), χ2=4.191, P=0.04; rs7270785(T)-rs4811528(T)- rs6023526(C), χ2=4.27, P=0.03. In female sample, there was1haplotype inassociation with chronic schizophrenia, which was rs2076380(G)-rs7270785(G)-rs4811528(A)-rs6023526(C), χ2=5.41, P=0.02.Conclusions: In male sample,2haplotypes may be associated with chronicschizophrenia, including rs4811528(G)-rs6023527(C) and rs7270785(T)-rs4811528(T)-rs6023526(C); in female sample,1haplotype may be associated withchronic schizophrenia, which was rs2076380(G)-rs7270785(G)-rs4811528(A)-rs6023526(C).