Polymorphisms within the Promoter Region of the Gamma Interferon (IFN-γ) Receptor1 Gene are Associated with the Susceptibility to Chronic HBV Infection in an Iranian Population

BACKGROUND chronic hepatitis B virus (HBV) infection is a multifactorial disease that can result in serious clinical complications. Host genetic background especially the genes that encode immunologic factors like INF-γ and its receptor (IFN-γ R) are critical in the pathogenesis of infection. OBJECTIVES The current study aimed to investigate the association between two single nucleotide polymorphisms (SNPs) at positions -611 and -56 within the promoter region of gamma interferon receptor1 gene (IFN-γ R1) and chronic HBV infection. MATERIALS AND METHODS Genomic DNA from peripheral blood samples of 200 chronically HBV infected patients and 200 healthy blood donors, as controls, were collected and genomic DNA was extracted by phenol-chloroform method and DNA analysis genotype identification was performed by PCR-RFLP. RESULTS The results indicated that both SNP's frequency had a significant difference in the patient and control groups. At position -56, TT genotype was associated with patient group and P value was 0.002 and at position -611, GG genotype was further observed in control group and P value was 0.006. CONCLUSIONS Presence of G allele at position -611 within promoter of IFN-γ R1 gene in the enrolled population for the study was related to lower risk of disease, and presence of T allele at position -56 was also related to susceptibility to chronic HBV infection. Men had higher frequency of chronic HBV infection, which might be the result of high risk behavior.