Replication of hepatitis delta virus.

Hepatitis delta virus (HDV) is a unique viroid-like human pathogen that is always associated with hepatitis B infection. Replication of HDV involves the transcription of genomic RNA, probably by the host RNA polymerase II, by a rolling circle mechanism followed by self-cleavage and self-ligation. Editing of antigenomic RNA, possibly involving the enzyme adenosine deaminase, generates two functionally distinct forms of delta antigen. The molecular basis for HDV pathogenicity remains uncertain.