Association of P2X7 Gene Polymorphisms with Chronic Hepatitis B Virus Infection in Duhok, Iraqi Kurdistan

Abstract

Host and viral factors are important determinants in the pathogenesis of chronic HBV infection. To date, polymorphisms in several genes such as tumor necrosis factor-alpha, tripartite motif-containing 22, have been found to contribute to the risk of developing chronic HBV infection. The polymorphism in P2X7 gene has recently been demonstrated to be associated with susceptibility or resistance to infectious diseases. However, still no clear association between P2X7 gene and chronic HBV infection has been reported in the literature. Hence, this study aimed to investigate whether two polymorphisms of P2X7 (1513 and -762) genes confer susceptibility to chronic HBV infection. In a case control study, single nucleotide polymorphisms (SNPs) in P2X7 (1513, -762) genes were assessed using allele-specific PCR and PCR- RFLP. Thereafter, frequency of the genotypes and alleles in patients and control groups were compared and analyzed. For the 1513 loci, the heterozygosity (AC) was higher in patients (73; 50.0%) than controls (14; 23.3%) [P = 0.001, OR 3.286, 95% CI 1.587-6885]. Furthermore, we found that the C allele was a risk factor for predisposition to chronic HBV infection (P = 0.006, OR 2.247, 95% CI 1.207-4.231). For the -762 loci, there were no significant statistical differences between the case and control groups in the genotype and allele frequencies (P > 0.05). In conclusion, in our study population, the P2X7 gene polymorphisms could be associated with susceptibility to chronic HBV infection.