Wang H, Chen H, Xia N, Tan W, Chen G, Liu Y, Cong Y, Sun J, Zeng D, Hou Y, Wang Y, Zhan M
Institute of Virology, Beijing 100052, China.
Chin Med J (Engl). 1999 Aug;112(8):747-9.
To obtain full-length sequence of a Chinese hepatitis G virus (HGV) strain (HGVch) and investigate the genetic characteristic of HGVch and its identity to other isolates.
Reverse transcription (RT) and nested-PCR were used to screen HGV RNA positive serum and amplify cDNA fragments. A positive serum without known hepatitis virus markers was selected for isolating HGV RNA template. The HGV genome was divided into 12 overlapping fragments and directly cloned into pGEM-T vector. Sequences were determined by dideoxy terminus-end method of DNA sequencing and then analyzed by computer.
The twelve fragments of HGVch cover 9213 nucleotides in length, containing a large open reading frame (ORF) encoding 2873 animo acids polyprotein that began with a methonine residue and ended at termination codon. HGVch is about 86.5%-89.5% identical to other known HGV isolates at the nucleotide level and about 93.9%-96.2% at the deduced animo acid level.
HGV is a non-A-E hepatitis causal agent, proved to be related with posttransfusion hepatitis in all over the world. Chinese HGV isolate has very close relationship to other isolates from Africa, Europe, Japan, without significant difference across the entire genome. It is suggested that the sequences of HGV isolates are very conservative and the evolution is very slow.
获取一株中国庚型肝炎病毒（HGV）毒株（HGVch）的全长序列，研究HGVch的基因特征及其与其他分离株的同源性。
采用逆转录（RT）和巢式PCR筛选HGV RNA阳性血清并扩增cDNA片段。选择一份无已知肝炎病毒标志物的阳性血清用于分离HGV RNA模板。将HGV基因组分为12个重叠片段，直接克隆到pGEM-T载体中。采用DNA测序的双脱氧末端终止法测定序列，然后进行计算机分析。
HGVch的12个片段全长9213个核苷酸，包含一个大的开放阅读框（ORF），编码2873个氨基酸的多聚蛋白，起始于一个甲硫氨酸残基，终止于终止密码子。HGVch与其他已知HGV分离株在核苷酸水平上的同源性约为86.5%-89.5%，在推导的氨基酸水平上约为93.9%-96.2%。
HGV是一种非甲-戊型肝炎病原体，在世界各地被证明与输血后肝炎有关。中国HGV分离株与来自非洲、欧洲、日本的其他分离株关系非常密切，整个基因组无显著差异。提示HGV分离株的序列非常保守，进化非常缓慢。
