Association of IFNAR2 and IL10RB genes in chronic hepatitis B virus infection

In this study, we investigated the effects of two functional polymorphisms, type I interferon receptor 2 gene (IFNAR2)-F8S and interleukin-10 receptor subunit beta gene (IL10RB)-K47E, on chronic hepatitis B virus (HBV) infection. We included 227 Thai patients with chronic HBV infection [100 with hepatocellular carcinoma (HCC) and 127 non-HCC], 170 individuals with self-limited HBV infection and 150 healthy controls. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to analyze these two single nucleotide polymorphisms (SNPs). In this study, the C allele of IFNAR2-F8S was found to be significantly increased in chronic HBV patients when compared with healthy controls [odds ratio, OR (95% confidence interval, CI)= 3.31 (2.11-5.21), P = 6.214x10(-9) and corrected P-value, P-c = 1.864x10(-8)]. The effect of this allele was similar to that of an autosomal dominant gene in the presence of CC and CT genotype, when compared to TT with an OR of 4.02 (P = 4.631x10(-9) and P-c = 1.389x10(-8)). Furthermore, AA genotype of IL10RB-K47E was found to be significantly decreased in chronic HBV patients compared with individuals with self-limited HBV infection (P = 0.006, P-c = 0.018 and OR=0.45). For haplotype analysis, we found CA and CG haplotypes were associated with susceptibility to chronic HBV (P = 0.014, OR=6.84 and P = 0.002, OR=3.75, respectively) when compared with healthy individuals. This study suggests that IFNAR2-F8S polymorphisms might be involved in the susceptibility to chronic HBV infection. Moreover, AA genotype of IL10RB-K47E may provide a protective effect in this disease. However, an association study using a larger sample size should be performed to confirm these findings.