title: Hepatitis B virus genotypes.
abstract: Eight genotypes of hepatitis B virus (A-H) are currently recognized, and subgenotypes have recently been described in four of these genotypes (A, B, C and F). The genotypes show a distinct geographical distribution between and even within regions, and are proving to be an invaluable tool in tracing the molecular evolution and patterns and modes of spread of hepatitis B virus. Structural and functional differences between genotypes can influence the severity, course and likelihood of complications, and response to treatment of hepatitis B virus infection and possibly vaccination against the virus. Although the number of studies on these genotypes has increased dramatically during recent years, much remains to be learnt about their full implications.
authors.affiliation: MRC/University Molecular Hepatology Research Unit, Department of Medicine, University of the Witwatersrand Medical School, 7 York Road, Parktown, 2193 Johannesburg, South Africa. kramvisa@medicine.wits.ac.za
authors.forename: Anna
authors.initials: A
authors.lastname: Kramvis
authors.forename: Michael
authors.initials: M
authors.lastname: Kew
authors.forename: Guido
authors.initials: G
authors.lastname: François
mesh_terms: D000818:Animals; D019143:Evolution, Molecular; D005838:Genotype; D006509:Hepatitis B / Q000821:virology*; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics*; D006801:Humans; D017720:Molecular Epidemiology; D010802:Phylogeny