Review ArticleGenetic variations of hepatitis B virusTong, C.Y. William Author Information Virology Section, Department of Infection, St Thomas Hospital, London, UK Correspondence to C.Y. William Tong, Virology Section, Department of Infection, 5th Floor North Wing, St Thomas Hospital, London SE1 7EH, UK. Tel: +44 20 7928 9292 (ext. 2405); fax: +44 20 7922 8387; e-mail: [email protected] Abbreviations anti-HBc: antibodies against hepatitis B core antigen anti-HBe: antibodies against hepatitis B e antigen HBcAg: hepatitis B core antigen HBeAg: hepatitis B e antigen HBsAg: hepatitis B surface antigen HBV: hepatitis B virus ORF: open reading frame Current Opinion in Infectious Diseases 13(5):p 481-487, October 2000. Buy Abstract The emergence of hepatitis B virus genetic variants occurs under the influence of host immunity, immunization, the use of immune globulin or antiviral chemotherapy. Most of these are probably the result of the ‘immune escape’ phenomenon. Some variants, in particular those in the precore and core promoter regions, have been associated with disease severity and progression. Surface antigen variants have implications for the accuracy of laboratory diagnosis and may reduce the effectiveness of vaccination. Polymerase variants are selected as a result of the use of antiviral chemotherapeutic agents. It is important to monitor the occurrence of these variants. © 2000 Lippincott Williams & Wilkins, Inc.