New pieces on genetic diversity and evolutionary history of hepatitis B virus: Characterization of the novel subgenotype F6

Abstract

Hepatitis B virus (HBV) is a globally distributed human pathogen that causes acute and chronic infections. HBV shows a high genetic heterogeneity and has been classified into at least eight genotypes (A-H), based on an intergroup nucleotide divergence greater than 7.5% in the complete genome sequences. Moreover, “subgenotypes” are defined as groups characterized by a divergence between 4% to 7.5%, and “clades” are subgroups showing less than 4% nucleotide divergence (Kramvis et al., 2008; Shi et al., 2013).