Association of polymorphism in MicroRNA 219-1 with clearance of hepatitis B virus infection.

Polymorphisms in the primary microRNA region may be associated with natural course of hepatitis B virus (HBV) infection. This study evaluated if the mircoRNA 219-1 (miR-219-1) polymorphism can influence the susceptibility towards persistence of HBV infection and the progression to hepatocellular carcinoma (HCC) in patients with chronic HBV infection. A total of 1,439 individuals having either past or present evidence of HBV infection were enrolled for the study. The subjects were divided into four groups; (1) spontaneous recovery (n = 404), (2) chronic HBV carrier (n = 313), (3) chronic HBV carrier with cirrhosis (n = 305), and (4) hepatocellular carcinoma (n = 417). Genotyping was performed at three polymorphic variants (rs421446, rs107822, and rs213210) in the pri-miRNA region of miR-219-1. The rs421446 T allele was found to be strongly associated with HBV clearance (OR = 0.73, P = 0.0005 in a codominant model and OR = 0.67, P = 0.0009 in a dominant model, OR = 0.69, P = 0.04 in a recessive model, respectively). The rs107822 G allele was also found to be associated with HBV clearance (OR = 0.79, P = 0.008 in a codominant model and OR = 0.72, P = 0.01 in a dominant model, respectively). In haplotype analysis, ht2 (T-G-T) and ht1 (C-A-C) were found to be in significant association with the clearance of HBV. However, no significant association was observed between miR-219-1 polymorphism and the risk of HCC occurrence. This result suggests that polymorphisms in the pri-miRNA region of miR-219-1 might be a genetic factor for HBV clearance after infection.