Characterization of hepatitis D virus genotype III among Yucpa Indians in Venezuela.

The complete genome sequences of hepatitis D virus (HDV) strains isolated from three Yucpa Amerindians in Venezuela were determined and found to be genotype III. Comparison of these three genotype III sequences demonstrated the presence of a hypervariable region containing numerous substitutions, insertions/deletions and a highly conserved region containing the self-cleavage domains, which have been reported previously for genotypes I and II. Amino acid changes within the first 90 amino acids of the hepatitis D antigen (HDAg) were found in the genotype III sequences, while the remainder of the HDAg-coding sequence was conserved. The secondary structure for the RNA-editing site differed between genotypes I and III. It was concluded that the serious delta hepatitis outbreaks characterized epidemiologically in the Yucpa Amerindians were caused by HDV genotype III isolates that were related to HDV genotype III isolates from other regions of South America.