[Hepatitis B and C virus mutants--clinical relevance].

Hepatitis B virus (HBV) mutants and hepatitis C virus (HCV) genotypes have recently been identified in patients with acute and chronic infections. Mutations may be associated with a specific clinical course of infection, e.g. chronic active or fulminant-hepatitis as well as the development of hepatocellular carcinoma (HCC). Further, mutations may affect clearance of HBV or HCV infection and the response to antiviral therapy with alpha-interferon; however, the exact contribution of specific mutations organotypes to the course of HBV or HCV infection remains to be established.