Association Studies On IGF2BP2, SlC30A8 Gene Polymorphisms And Schizophrenia In Chinese Han Population

Objective:Schizophrenia is a serious mental disorder characterized by the abnormal mental functions and disturbed behaviors, which characteristically appears as a series of clinical features, such as positive and negative symptoms, and disturbances in basic cognitive functions. It belongs to complex diseases and its cause remains unknown. It is quite imperative to establish a procedure of treating and preventing schizophrenia, since the illness causes heavy economical and social burdens to families and societies. Type 2 diabetes mellitus is one of the important diseases threatening human Health in the world at present and is an important risk factor for many diseases. Up to now its pathogenesy is not clear. It is thought to be a complication that results from an interaction between genetic back ground and environmental factors now.Over the past decade, serious efforts have been put into the search for T2DM susceptibility genes, but progress has been slower than anticipated. Recently, significant progress of T2DM susceptibility gene studies was made by genome-wide association studies (GWAS) which have identified common variants in CDKAL1, CDKN2A/B, IGF2BP2, SLC30A8, HHEX, PPARG, KCNJ11, EXT2 and LOC 387761 loci that significantly increase risk of T2DM in several studies of European descents. But the contributions of these genetic variants in other ethnic groups are less clear. In parent study, we aimed to elucidate the genetic association between IGF2BP2, SLC30A8 gene polymorphisms and schizophrenia in a Han descent population in the north of China.Methods:Genomic DNA was isolated from the whole blood samples. A single nucleotide polymorphism, rs4402960 present in the IGF2BP2 gene and rs 13266634 present in the SLC30A8, was detected using PCR-based restriction fragment length polymorphism (PCR-RFLP) analysis among 790 Chinese Han patients with schizophrenia and 1083 ethnicity-matched healthy controls. The Hardy-Weinberg equilibrium for genotypic distribution was estimated by the goodness-of-fitχ2 test. The relationship between frequencies of alleles and genotypes of SNPs and schizophrenia and its clinical phenotypes were statistically computed.Results:The goodness-of-fitχ2 test showed that the genotypic distributions of rs13266634 did not deviate from Hardy-Weinberg equilibrium in both patient group and control group (P>0.05). Theχ2 test did not show allelic association and genotypic association for rs13266634 (P>0.05). There were no correlations between allelic or genotypic frequencies and the clinical phenotypes of schizophrenia (P>0.05)The goodness-of-fitχ2 test showed that the genotypic distributions of rs4402960 did not deviate from Hardy-Weinberg equilibrium in both patient group and control group (P>0.05). Theχ2 test show allelic association for rs4402960 (χ2=7.056, P= 0.008) and show genotypic association for rs4402960 (χ2=7.316, P=0.026). There were no correlations except for delusion of observation (χ2=4.145, P=0.042) between allelic or genotypic frequencies and the clinical phenotypes of schizophrenia (P>0.05)Conclusion:The SLC30A8 locus may not be associated with schizophrenia, IGF2BP2 locus may be associated with schizophrenia and it may be a shared susceptibility gene in Chinese Han population.