Widespread hepatitis B virus genotype G (HBV-G) infection during the early years of the HIV epidemic in the Netherlands among men who have sex with men

Background Hepatitis B virus (HBV) variants belong to different genotypes, A-J, whose worldwide distribution is linked with geography, probably because viral spread was associated with ancient human migrations. HBV genotype G (HBV-G) is an aberrant genotype with little sequence divergence, suggesting a recent origin. HBV-G is strongly associated with certain risk groups such as intravenous drug users (IDUs) and men who have sex with men (MSM), but hardly with geography. The origin and epidemiology of HBV-G remain unresolved, as is the disease association.