Nucleotide sequence analysis of new genotype of hepatitis G virus in population at high risk for HCV infection in Guangxi

Objective To examine the prevalence and the sequence of the genes of new genotypes of hepatitis G virus (HGV) in Guangxi, China. Methods Serum samples were collected from 85 intravenous drug abusers (IVDAs), 80 patients with liver diseases (PLDs) and 50 blood donors (BDs). All sera ( n =215) were tested by using EIA for HBsAg,anti HCV and anti HIV, and by using nested PCR for HGV RNA. In 62 subjects positive for HGV, HGV RNA was sequenced, and a phylogenetic tree was constructed for analyzing genotypes of HGV.Results HGV RNA was detected in 85 of 215 serum samples (39.53%). The positivity rates for HBsAg, anti HCV and anti HIV were 39.07%,42.79% and 0, respectively. First, 11 nucleotide sequences were determined and the isolates were grouped into three clusters with HGV. 5 of 11 HGV isolates clustered in a distinct phylogenetic branch (genotype Asia)which was different from the described GBV C and HGV sequences, suggesting the presence of a new genotype of HGV in this locality. Second, 51 nucleotide sequences were determined and analyzed for their genotypes of HGV, and showed genotype GBV C (3.23%),genotype HGV 30 65% and new genotype (genotype Asia)64.51%,respectively. Conclusion There were subgenotypes in 3 genotypes of HGV;The predominant genotypes of HGV were genotype Asia and genotype HGV among IVDAs, PLDs, and BDs patients in Guangxi, China.