Objective: To study the genotype distribution of hepatitis G virus (HGV) isolated from different population in some areas of China.
Methods: A total of 12 strains of HGV were isolated from different areas of China (three from Guangxi Zhuang Autonomous Region, three from Hebei Province, one from Heilongjiang, Jiangxi, Guangdong, Jiangsu, Anhui, Jilin Provinces and Xinjiang Autonomous Region each). The HGV 5' untranslated region (UTR) of the 12 isolates was sequenced and compared with other 26 isolates previously reported (17 from China and nine from other countries).
Results: The nucleotide sequences of five HGV clones isolated from the same patient with HGV infection were identical, with the homology of 99.1% - 100%, indicating that variation of HGV in the same human body was very limited. Genotyping could be based on the sequence of one positive clone isolated from a patient with HGV infection. The homology of the nucleotide sequences in the 12 isolates was 96.8% - 99.4%, suggesting that they belonged to the same genotype. The homology of the 12 isolates was 88.0% - 89.7%, 87.2% - 90.3% and 94.7% - 96.3%, respectively, as compared with HGV genotypes 1 (U36380), 2 (U44402) and 3 (D90601), which indicated that all the 12 HGV isolates belonged to genotype 3. Phylogenetic distance analysis of the 38 isolates suggested that HGV strains isolated from China could be further divided into different subgroups.
Conclusion: The majority of Chinese HGV isolates belonged to genotype 3 and they could be further divided into different subgroups.