A nationwide molecular epidemiological study on hepatitis B virus in Indonesia: identification of two novel subgenotypes, B8 and C7

Upon phylogenetic analysis of a partial S gene sequence [396 nucleotides (nt)], 928 hepatitis B virus (HBV) strains obtained from 899 viremic subjects in 28 major cities on 15 islands of Indonesia in 1989-2007 segregated into four HBV genotypes. Genotype B was predominant (66%), followed by genotype C (26%), genotype D (7%), and genotype A (0.8%). Comparative and phylogenetic analyses of the 396-nt S gene sequence of 928 HBV isolates and whole genomic sequences of 25 selected HBV isolates revealed a total of 14 subgenotypes within genotypes A-D: two (A1 and A2) in genotype A (HBV/A), five (B2, B3, B5, B7, and a novel subgenotype, tentatively designated B8) in HBV/B, five (C1, C2, C5, C6, and another novel subgenotype, C7) in HBV/C, and two (D1 and D3) in HBV/D. The distribution of HBV genotypes/subgenotypes, including B8 and C7, seems to be associated with ethnological origins in Indonesia.