丙型肝炎病毒1b型NS5 A区基因结构变异与α干扰？…

目的 观察丙型肝炎患者丙型肝炎病毒（ＨＣＶ）１ｂ型基因组部分ＮＳ５ Ａ区核苷酸，氨基酸的变异情况并探讨其与α干扰素疗效的相关性。方法 患者干扰素治疗前，中，后留血标本，用聚合酶链反应（ＰＣＲ）扩增ＨＣＶ病毒ＮＳ５ Ａ区部分基因片段并用直接测序法测序。与ＨＣＶ－Ｊ株及ＨＣＶ－河北株（ＨＣＶ－ＨＢ）比较核苷酸及氨基酸序列的同源性，根据α干扰素疗效分析ＨＣＶ１ｂ是否存在干扰素敏感决定区。

Analysis of genome character and amino acid residues 2 209 to 2 248 of NS5 A region of hepatitis C virus in relation to the response to interferon therapy

OBJECTIVE: To observe nucleotide sequence variations and amino acid residues 2,209 to 2,248 of the NS5 A region of hepatitis C virus in relation to interferon therapy in Chinese patients infected with HCV genotype 1b. METHODS: We collected sera from 22 patients infected with HCV genotype 1b, performed nested RT-PCR using extracted serum RNA from sera, amplified NS5 A region 2,209 to 2,248 and sequenced the PCR product directly. The deduced amino acid sequences were compared with the corresponding region of the HCV-J prototype strain. RESULTS: Only 4 isolates were intermediate type, and no mutant type was found. In 18 patients treated with IFN-alpha, only 4 were HCV RNA negative at present, No correlation was found between amino acid mutation and IFN response. CONCLUSION: Variations in the NS5 A region between amino acid residues 2,209 to 2,248 failed to predict IFN response in Chinese patients infected with HCV genotype 1b. IFN may accelerate nucleotide variation but has little influence on amino acid variations.