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为探讨丙型肝炎病毒（ＨＣＶ）感染在肝癌发生中的作用，从３５例ＨＣＶ－ＲＮＡ阳性的非甲非乙型肝病患者血清中提取ＨＣＶ－ＲＮＡ，经随机引物逆转录合成ｃＤＮＡ，在病毒的Ｃ基因区进行分型，再于病毒５＇－末端至Ｅ１区间以多对引物进行巢式ＰＣＲ扩增，其最终产物（４２５ｂｐ和６２１ｂｐ）分别连接ｐ－ＧＥＭ－Ｔ载体，在大肠杆菌中表达后进行测序分析。ＨＣＶ基因型表现为８２％Ⅱ型，９％Ⅲ型及９％Ⅱ＋Ⅲ混合型。核心蛋白基因（５７３ｂｐ）与已报道的其他株比较，其核苷酸同源性为：慢性肝炎株９３．０±２．４％，肝癌株９１．４±１．５％；氨基酸同源性为：前者９３．９±０．８％，后者９１．０±１．６％；核心蛋白基因中核苷酸置换在肝癌株较明显地高于慢性肝炎株。研究结果提示，ＨＣＶ核心蛋白基因的错义突变，与ＨＣＶ的慢性持续感染及肝癌发生的关系密切。
To investigate the role of hepatitis C virus (HCV) in the pathogenesis of hepatocellular carcinoma, HCV-RNA was extracted from serum of 35 patients with HCV-RNA positive non-A non-B hepatitis and reverse transcribed into cDNA by random primers. C gene region was typed. Then, multiple pairs of primers were used for nested PCR amplification at the 5’-end of the virus. The final products (425 bp and 621 bp) were respectively linked to the p-GEM-T vector and expressed in E. coli After sequencing analysis. HCV genotypes showed 82% type Ⅱ, 9% Ⅲ and 9% Ⅱ + Ⅲ mixed type. The nucleotide sequence of core protein (573bp) was 93.0 ± 2.4% for chronic hepatitis B and 91.4 ± 1.5% for hepatoma, compared with the other reported strains. Amino acid homology The former was 93.9 ± 0.8% and the latter 91.0 ± 1.6%. Nucleotide substitutions in the core protein gene were significantly higher in hepatocellular carcinoma than those in chronic hepatitis. The results suggest that the HCV core protein gene missense mutation, and HCV chronic persistent infection and the occurrence of liver cancer are closely related.