Genetic Association Between The Polymorphism Of TPH2 Genes And Schizophrenia

Objective This study aims to explore the association of the two single nucleotide polymorphisms(SNPs)rs4570625,rs4131347 of Tryptophan Hydroxylase 2 gene promtor region with schizophrenia in Yunnan Han Nationality,and to determine the influence of the two SNPs on symptoms components,depressive symptoms,the age of onset and aggression behavior.Methods A case-control study was designed,and the blood samples came from 102 patients and 100 health controls who are Han Nationality in Yunnan province.Polymerase Chain Reaction-Restriction Fragment Length polymorphisms (PCR-RFLP)technique was used to detect rs4570625,rs4131347 polymorphisms.All patients were evaluated with the positive and negative syndrome scale(PANSS)and the Overt Aggression Scale(OAS).Association analysis was carried out between the polymorphism and schizophrenic symptoms,and depression,and age of onset,and aggression behavior in all the schizophrenic samples.Results(1)No significant difference genotype and allele frequency of the 2 loci was observed in Yunnan Han Nationality samples(P＞0.05),but the G/G genotype frequency ofrs4570625 is significantly higher in male patients than in male controls(P=0.008,OR=5.6,95%CI:1.583～19.808).For male group,the frequency of allele TPH2-703G is significantly higher in patients than in controls (P=0.015,OR=1.956,95%CI:1.138～3.363),but not in female patients than in female controls(P＞0.05).(2)No significant difference genotype and allele frequency of the 2 loci was observed in violent and nonviolent patient group of Yunnan Han Nationality samples(P＞0.05).The frequency of allele TPH2-8396C was significantly higher in male violent patients than in male nonviolent patients(P=0.021,OR=2.5,95%CI:1.148～5.445),but not in female violent patients than in female nonviolent patients(P＞0.05).(3)No significant difference genotype and allele frequency of the 2 loci was observed in early and late onset schizophrenic patients group of Yunnan Han nationality samples(P＞0.05).(4) No significant difference genotype and allele frequency of the 2 loci was observed in depressive symptoms and non-depressive symptoms with schizophrenic patients group of Yunnan Han nationality samples(P＞0.05).(5)No significant association genotype of the 2 loci with scores of PANSS was observed(P＞0.05).Conclusions(1)Tph2G-703T polymorphism may be associated with the vulnerability of male Han nationality schizophrenia in Yunnan,the variant of the G allele may contribute to the morbidity.(2)The TPH2 gene polymorphism was associated with aggressive behavior of male Han nationality schizophrenic patients in Yunnan,and the -8396C alleles of male schizophrenic patients may contribute to aggressive behavior.(3)There was no association between the polymorphism and the depressive emotion with schizophrenic patients of Han nationality in Yunnan.(4)There was no association between the polymorphism and the onset age of schizophrenic patients of Han nationality in Yunnan.