Three different GB virus C hepatitis G virus genotypes - Phylogenetic analysis and a genotyping assay based on restriction fragment length polymorphism

The 5'-untranslated region (5'-UTR) sequences of 33 GB virus C/hepatitis G virus (GBV-C/HGV) obtained from different geographic areas were determined through reverse-transcription polymerase chain reaction and dideoxy chain termination sequencing, the alignment of sequences, the estimation of the number of nucleotide substitution per site, and construction of phylogenetic trees, The 5'-UTR of GBV-HGV was found to be heterogeneous, with 70.9-99.5% homology. Three distinct phylogenetic branches were observed consistently in all phylogenetic trees, GBV-C is the prototype for one, HGV for another, and there is a new branch which consisted of GBV-C/HGV isolates from Asia, Genotype-specific restriction sites for the restriction enzymes, ScrFI and BsmFI, were identified, and a simple restriction fragment polymorphism analysis was developed for genotyping, These data provide evidence that GBV-C/HGV consists of three different genotypes, Our simple genotyping assay mill also provide a tool for epidemiological studies of GBV-C/HGV infection. (C) 1997 Federation of European Biochemical Societies.