IFNA1 and hepatitis B virus infection: The present study aimed to investigate the role of HBV genotypes and IFNAR2 in response to Peg-IFN-α-2a in Chinese patients with hepatitis B. Until now, based on an intergroup divergence of 8 % or more in the complete nucleotide sequence, HBV can be classified into nine genotypes (A-I) [14][15][16][17].