Background/purpose: Hepatitis delta virus (HDV) is the only animal RNA virus that has an unbranched rod-like genome with ribozyme activity. It replicates in the nucleus by host RNA polymerase via a rolling circle mechanism. Similar to many RNA viruses encoding their own RNA-dependent RNA polymerases, homologous recombination of HDV occurs in mixed-genotype infections and in cultured cells cotransfected with two HDV sequences, as demonstrated by molecular analyses.
Methods: Among 237 published complete genomic sequences, 34 sequences were reported from the small and isolated Miyako Island, Japan, and belonged to the Asia-specific genotypes, HDV-2 and HDV-4 (the majority of them belonged to the known Miyako Island-specific subgroup, HDV-4M). We investigated the presence of naturally occurring HDV recombinant in Miyako Island using phylogenetic and recombination analyses.
Results: We identified a two-switch HDV-4/4M intersubtype recombinant with an unbranched rod-like RNA genome.
Conclusion: Our data suggest that RNA recombination plays an important role in the rapid evolution of HDV, allowing the production of new HDV strains with correct genomic structures.
Keywords: RNA recombination; hepatitis delta virus.
Copyright © 2015. Published by Elsevier B.V.