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目的研究中国庚型肝炎患者分离的病毒基因的特异性及变异规律。方法应用逆转录－巢式聚合酶链反应（ＰＣＲ）技术从１６例庚型肝炎病毒（ＨＧＶ）感染住院病人血清中扩增了ＨＧＶＮＳ５区部分基因片段（１４１ｎｔ）。经纯化后采用双脱氧链末端终止法进行序列分析。结果观察到在ＨＧＶＮＳ５区第７８２０－７９６０核苷酸之间的５′端较３′端核苷酸及其编码氨基酸变异率高。与Ｌｉｎｎｅｎ等报道的美国株ＨＧＶ相比，中国人ＨＧＶＮＳ５区核苷酸的变异主要集中在ＨＧＶＮＳ５工第７８２４，７８４５～７８６０，７８９２，７９１４，７９１７和７９３５核苷酸位点及区域，各个核苷酸位点的变异率在０～８９．５％，与美国株相比核苷酸序列的同源性为８３．６％～９５．７％，平均８９．６％；氨基酸为８３．０％～１００％，平均为９１．２％。在７９３３核苷酸位点与美国株相比变异率为９３．７％。结论中国人群之间ＨＧＶＮＳ５区部分基因及其推测编码蛋白较保守，但与美国株有明显差别。不同硷基在序列中呈散在分布，而在某些位点虽与美国株相比变异很大，但中国人群之间离散度较小，ＨＧＶ核酸的变异可能与地域因素有关。
Objective To study the specificity and variation of viral genes isolated from patients with hepatitis G in China. Methods Reverse transcriptase-nested polymerase chain reaction (PCR) was used to amplify a portion of HGVNS5 gene fragment (141 nt) from 16 inpatients with hepatitis G virus (HGV) infection. After purification, sequence analysis was performed by dideoxy chain termination. As a result, it was observed that the 5 ’end of the nucleotide between the 7820th and the 7960th nucleotide in the HGVNS5 region had a higher mutation rate than the 3’end nucleotide and its encoded amino acid. Compared with the American strain HGV reported by Linnen et al., The nucleotide variation in Chinese HGVNS5 region mainly concentrated at the nucleotide positions and regions of HGVNS5 workers 7824, 7845-7860, 7892, 7914, 7917 and 7935, The mutation rate of the acid sites ranged from 0 to 89.5%. The homology of the nucleotide sequences to the American strain was 83.6% ~ 95.7% with an average of 89.6% and the amino acid was 83.0% ~ 100%, with an average of 91.2%. The mutation rate was 93.7% in the 7933 nucleotide compared with that of the American strain. Conclusion Some Chinese HGVNS5 genes and their putative encoded proteins are more conservative than those from the U.S. strain. The different bases are scattered in the sequence, while in some loci, although they vary greatly from those in the American strain, the dispersion among Chinese populations is small. The variation of HGV nucleic acid may be related to the geographical factors.