title: Hepatitis B virus taxonomy and hepatitis B virus genotypes.
abstract: Hepatitis B virus (HBV) is a member of the hepadnavirus family. Hepadnaviruses can be found in both mammals (orthohepadnaviruses) and birds (avihepadnaviruses). The genetic variability of HBV is very high. There are eight genotypes of HBV and three clades of HBV isolates from apes that appear to be additional genotypes of HBV. Most genotypes are now divided into subgenotypes with distinct virological and epidemiological properties. In addition, recombination among HBV genotypes increases the variability of HBV. This review summarises current knowledge of the epidemiology of genetic variability in hepadnaviruses and, due to rapid progress in the field, updates several recent reviews on HBV genotypes and subgenotypes.
authors.affiliation: Abteilung für Virologie, Institut für Medizinische Mikrobiologie, Virologie und Hygiene, Universität Rostock, Schillingallee 70, D-18057 Rostock, Germany. stephan.schaefer@med.uni-rostock.de
authors.forename: Stephan
authors.initials: S
authors.lastname: Schaefer
mesh_terms: D000818:Animals; D017917:Avihepadnavirus / Q000145:classification / Q000235:genetics; D004274:DNA, Recombinant / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D005838:Genotype; D006509:Hepatitis B / Q000453:epidemiology; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D017918:Orthohepadnavirus / Q000145:classification / Q000235:genetics; D010802:Phylogeny; D015995:Prevalence
chemical_list: D004274:DNA, Recombinant; D004279:DNA, Viral