不同基因型HCV膜区（E2）基因克隆及亲、疏水性分析

目的 研究丙型肝炎病毒（HCV）不同基因型膜区序列变异及其变异规律。方法 克隆不同基因型HCV的膜区基因，序列测定，核苷酸和氨基酸序列比较和分析。结果 不同基因型膜区基因相似性不同，从同一血清样本获得的不同克隆间，其同源性核苷酸大于99．2％，氨基酸大于99．9％。相同亚型核苷酸和氨基酸同源性大于80％。同型基因核苷酸和氨基酸同源性分别为（63．9－75．0）％和（64．9－72．8）％。异型基因同源性核苷酸为（59．4－67．0）％，氨基酸为（56．5－66．3）％。氨基酸序列变化在某些部位有一定保守性。不同基因HCV高变区（HVR）的亲水性和疏水性变化小于其下游3′端区域。结论 HCV基因变化可能有一定规律性。

Cloning of HCV envelop region of different genotype and analysis of their hydrophilicity and hydrophobicity

Objective To study gene variation of the hepatitis C virus (HCV) envelope region isolated from different genotypes (1a, 1b, 2a, 2c, 3a). Methods Genes of the envelope region (1300 1870nt) of different genotypes of HCV were cloned, sequenced and analyzed. Results The sequences of different HCV genome was not identical. The homology of the nucleotide sequences of different HCV clones isolated from the same sample was more than 99.2%, with the amino acid more than 99.9%. The homology of the nucleotides and amino acid sequences of the same subtype was more than 80%, whereas 63.9% 75.0% and 64.9% 72.8% for the homology of the nucleotides and amino acid sequences of the same type. The homology of the nucleotides sequences of different HCV types was 59.4% 67.0%, and 56.5% 66.3% for amino acid. Some amino acids among the sequences of different genotypes were relatively conservative. The hydrophilicity and hydrophobicity of the HVR region among different genotypes were less variable than that of its downstream gene. Conclusion Gene variation of HCV envelope region may have some regular patterns.