IFIT1 polymorphisms predict interferon-α treatment efficiency for hepatitis B virus infection

AIM: To investigate the association between interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) polymorphisms and interferon-α (IFNα) treatment efficiency among Chinese hepatitis B virus (HBV) infection patients. METHODS: Two hundred and twenty five newly diagnosed chronic hepatitis B (CHB) patients were enrolled in the study. All of these patients received IFNα treatment for a course of 48 wk, and were followed up for 24 wk after the treatment was end. Clinical information about virological response, hepatitis B e antigen (HBeAg) seroconversion rate and combined response at the end of the treatment, as well as the sustained response by the time of following up 24 wk after the treatment, was collected. Four tag-single nucleotide polymorphisms (SNPs) of IFIT1 were selected and assessed for their association with these clinical outcomes. RESULTS: At the end of the treatment, HBeAg seroconversion was observed in 27.1% patients. Thirty-six point nine percent patients achieved virological response, and 15.6% patients exhibited combined response. Sustained response was obtained in 26.2% patients. The main HBV genotype of the study was genotype B. Patients who infected with HBV genotype B or C showed better treatment efficiency, no matter which clinical outcome was considered. Among the four SNPs assessed, rs303218 (A > G) was found to be significantly associated with the end point virological response when assuming additive model [OR = 0.64 (95%CI: 0.42-0.96), P = 0.032]. Patients who carried rs303218 GG genotype had a rather higher rate of achieving virological response (response rate: 52%, OR = 0.40, 95%CI: 0.18-0.91; P = 0.028) when compared to those had AA genotype (response rate: 27%). The most significant interaction was observed in patients who had relative lower baseline aspartate transaminase. No association between SNPs and HBeAg seroconversion, combined response or sustained response was observed. CONCLUSION: IFIT1 involves in the regulation of IFNα treatment for CHB and its polymorphism rs303218 can predict the end point virological response. The finding requires further validation.