Hepatitis B virus genotypes and variants.
At least 10 hepatitis B virus (HBV) genotypes (A to J) with distinct geographic distributions and several HBV mutants, including precore/core promoter mutations and pre-S/S deletion mutations, have been recognized to be not only predictive of liver disease progression but also associated with response to antiviral therapy. HBV genotype-specific pathogenesis may contribute to heterogeneous clinical outcomes in chronic hepatitis B patients across the world. For example, patients with HBV genotypes C and D infection have a lower rate of spontaneous HBeAg seroconversion. In addition, HBV genotypes C and D have a higher frequency of core promoter and pre-S mutations than genotypes A and B. Genotypes C and D also carry a higher lifetime risk of cirrhosis and HCC development than genotypes A and B. Core promoter and pre-S mutations also correlate with an increased risk of hepatocellular carcinoma (HCC). Therapeutically, genotypes A and B patients have a better response to interferon-based therapy than genotypes C and D patients, but the response to nucleos(t)ide analogs is comparable across different HBV genotypes. In conclusion, HBV genotypes and variants may serve as viral genetic markers to predict disease progression as well as help practicing physicians optimize individualized antiviral therapy in clinical practice.
Department of Gastroenterology, Ren-Ai Branch, Taipei City Hospital, Taipei 106, Taiwan Department of Psychology, National Chengchi University, Taipei 106, Taiwan.
Chih-Lin
CL
Lin
Department of Internal Medicine, National Taiwan University Hospital, Taipei 100, Taiwan Graduate Institute of Clinical Medicine, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei 100, Taiwan Hepatitis Research Center, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei 100, Taiwan Department of Medical Research, National Taiwan University College of Medicine and National Taiwan University Hospital, Taipei 100, Taiwan.
Jia-Horng
JH
Kao
D000998:Antiviral Agents / Q000627:therapeutic use; D015415:Biomarkers / Q000097:blood*; D006528:Carcinoma, Hepatocellular / Q000821:virology*; D004279:DNA, Viral / Q000235:genetics; D018450:Disease Progression; D005838:Genotype; D006513:Hepatitis B e Antigens / Q000097:blood; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics*; D019694:Hepatitis B, Chronic / Q000821:virology*; D006801:Humans; D008113:Liver Neoplasms / Q000821:virology*; D009154:Mutation; D011401:Promoter Regions, Genetic
D000998:Antiviral Agents; D015415:Biomarkers; D004279:DNA, Viral; D006513:Hepatitis B e Antigens