上海地区庚型肝炎病毒感染的分子流行病学

Molecular epidemiology of hepatitis virus G in Shanghai

目的 了解 Ｈ Ｇ Ｖ 的感染及分子病毒学特征。方法 设计针对 Ｈ Ｇ Ｖ 基因组５′－ Ｎ Ｃ Ｒ和 Ｎ Ｓ３ 的引物，利用逆转录－ 聚合酶链反应（ Ｒ Ｔ Ｐ Ｃ Ｒ） 对上海地区不同人群进行血清 Ｈ Ｇ Ｖ Ｒ Ｎ Ａ 的检测，并对 Ｐ Ｃ Ｒ 产物进行测序、分析。结果 Ｈ Ｇ Ｖ 感染普遍存在于乙肝（１５ ％ ） 、丙肝患者（２１ ％ ） 及具有肠道外肝炎感染高危因素的人群（ 静脉吸毒者为７２ ．５ ％ ，肾透析患者为１４ ％ ） ，且多为乙肝、丙肝病毒的混合感染（ 合并感染率为７５ ．９ ％ ） ；在非甲～戊型肝炎患者中的检出率仅为５ ．３ ％ 。部分 Ｐ Ｃ Ｒ阳性标本的测序和分析表明， Ｈ Ｇ Ｖ５′ Ｎ Ｃ Ｒ 在不同地区分离株间存在高度同源性（ 与国内外报道株的同源性在９１ ．１５ ％ ～９８ ．２３ ％ 之间） ； Ｎ Ｓ３ 区虽在核苷酸水平上变异较大（ 与国内外报道株的同源性在８３ ．２３ ％ ～９２ ．２２ ％ 之间） ，但在氨基酸水平上无明显变化（ 同源性为９６ ．３６ ％ ～９８ ．１８ ％ 之间） 。结论 庚型肝炎病毒在上海地区多为混合感染； Ｈ Ｇ Ｖ 基因组存在相对保守性。

Objective To investigate the characteristics of HGV/GBV C infection and its moleculer biology. Methods Serum samples from blood donors, intravenous drug abusers, patients with chronic hepatitis B and C, hemodialysis patients and non A E hepatitis patients in Shanghai city were analyzed by a highly sensitive nested RT PCR using primers specific for the 5′ non coding region of HGV genome. For part of the positive samples, HGV RNA was also amplified with two sets of primers derived from NS3 helicase region of HGV genome. The nucleotide sequences of selected PCR products were determined and analyzed by multiple sequence alignments. Results Viral RNA was detected in 3/57 non A E hepatitis patients(5.3%), 7/50 hemodialysis patients(14%), 29/40 intravenous drug abusers(72.5%), 8/53 hepatitis B(15%) and 7/34 hepatitis C patients(21%), whereas none in the 20 ALT normal blood donors. Above all, 41/54 HGV RNA positive patients(75.9%) were co infected by hepatitis B and/or C virus. Sequence analysis of PCR products revealed that the nucleotide sequence of 5′ NCR region were highly conserved(91.15～98.23% homology). Although the changes at the NS3 region were apparent at the nucleotide level(83.23%～92.22% homology), the amino acid sequences were highly conserved(96.36%～98.18% homology).Conclusion HGV/GBV C infections are common among hepatitis(B,C) patients and persons with high risk factors for parenteral hepatitis virus infection. The considerable similarity at the nucleotide and amino acid sequence among isolates from different regions indicates the conservation of HGV genome. (Shanghai Med J, 1999,22∶603 605)