The molecular biology of hepatitis B virus.

Techniques of recombinant DNA and molecular biology have recently been applied to the study of hepatitis B virus (HBV) in human tissues and have enhanced our knowledge of viral persistence and chronic liver disease. These molecular studies strengthen previous epidemiologic evidence for an association between HBV chronic carriers and hepatocellular carcinoma (HCC). A recently described group of animal viruses with structural and biological properties similar to HBV, termed Hepadna viruses, provides animal models for future studies of hepatitis B virus, especially with regard to the mechanisms for virus replication and persistance and the relationship of these processes to development of HCC.