The Relationships Between IFN-γ Gene Polymorphism And Hepatitis C Virus Infection In An Epidemic Region In Fujian Province

Objective: This study is aiming to investigate the relationships between the polymorphism of interferon-gamma gene and susceptibility to hepatitis C virus infection.Methods : A total of 186 cases with HCV infection in a highly epidemic region in Fujian province, and 191 cases of normal control were enrolled in this case-control study. The polymorphisms of IFN-γ+874(rs2430561)、-183(rs2069709)and-764(rs2069707) were identified using the Taq Man Methods. Their frequencies were calculated. The population distribution in control group was tested using Hardy–Weinberg equilibrium and the frequencies of the genotypes between the two groups were compared using the Pearson chi-squared test.Results:⑴The allele distribution for IFN-γ+874 is consistent with Hardy-Weinberg equilibrium measurements(P>0.05),which indicates that the selected control group represents statistically acceptable sample.(2) There are two allele(T and A) and three genotypes(TT, TA and AA) at IFN-γ+874. The frequency of T allele in HCV and control groups were 85.42% and 86.83%,respectively, while A allele were 14.58% and 13.17%, respectively. There were no significant differences of IFN-γ+874A/T allele frequency between the HCV group and the control group(χ2=0.315,P=0.575). The differences in TT and AT genotype frequency between cases and controls were not statistically significant(71.35% vs 74.19%,28.13% vs 25.27%,respectively). The frequency of AA genotype in cases and controls were both less than 1%. There were no significant differences of IFN-γ+874 genotypes frequency between the HCV group and the control group(χ2=0.394,P=0.821). ⑶ Logistic regression analyses revealed that the +874 polymorphism had no association with HCV. ⑷ All participants had G allele and GG genotype at-764 and-183 sites. ⑸ The relationship between allele, genotypes and gender or HCV RNA load: We re-assigned the participants into two groups: A group with +874TT genotype, and B group with +874AT or AA genotypes. No significant difference was observed in gender and HCV-RNA level between two groups(χ2=0.019,P=0.891;χ2=0.424,P=0.515, respectively). And there were no significant relationships between T/A allele and gender or HCV-RNA level(χ2=0.002,P=0.962;χ2=0.239,P=0.625, respectively).Conclusions:⑴ Our findings indicate there are polymorphisms of IFN-γ +874 site in the study population, but not at position-183 and-764.⑵ There was no significant relationships between the polymorphism of IFN-γ +874 and susceptibility to HCV infections.