The genotypes and sequence characteristics of NS5B region of subtype 1b among hepatitis C viruses in Liuzhou, Guangxi, from 2014 to 2018
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摘要:
目的 分析2014―2018年广西柳州市丙型肝炎病毒(hepatitis C virus,HCV)的基因型分布和HCV 1b亚型NS5B区的序列特征。 方法 收集慢性丙型病毒性肝炎患者血清,提取HCV RNA,反转录后用巢式PCR扩增NS5B区序列,测序后构建进化树分析HCV基因型和基因亲缘关系。用聚类分析法对比HCV 1b本地群、非本地群和参照株NS5B区基因和蛋白序列的差异。 结果 广西柳州市HCV流行的基因型包括1a、1b、2a/c、3a、3b、6a、6c/d和未分型(NT),分别占3.39%、43.01%、0.42%、13.98%、6.99%、28.81%、3.18%和0.21%;HCV 1b亚型中61.6%的病毒与各参照株进化距离均较远,其比例在2014―2018年分别占HCV 1b亚型的69.8%、78.6%、43.3%、47.6%和59.6%;该群HCV的NS5B基因有15个经常性突变位点,可导致NS5B蛋白I2682V和S2755N发生经常性变异。 结论 广西柳州市HCV流行的主导基因型依次为1b、6a和3a;HCV 1b亚型中的大部分属于本地亲缘性群,该群HCV的NS5B蛋白存在特征性的变异位点并可能影响直接抗病毒药的作用。 Abstract:Objective To analyze the genotypes distribution of hepatitis C virus(HCV)and the sequence characteristics of NS5B region of HCV subtype 1b from 2014 to 2018 in Liuzhou, Guangxi. Methods HCV RNA was extracted from serum of patients with chronic hepatitis C, and the NS5B gene was amplified by nested PCR after reverse transcription. The genotype and genetic relationship of HCV were analyzed by gene sequencing and constructing gene evolutionary tree. The differences of NS5B gene and protein sequence among local, non-local and reference strains of HCV 1b were compared by cluster analysis. Results The genotypes of HCV epidemic in Liuzhou included 1a, 1b, 2a/c, 3a, 3b, 6a, 6c/d and undermined type(NT), which accounted for 3.39%, 43.01%, 0.42%, 13.98%, 6.99%, 28.81%, 3.18% and 0.21%, respectively. The evolutionary distances for 61.6% of the HCV 1b subtype were far away from those of the reference strain. From 2014 to 2018, the proportion of this group accounted for 69.8%, 78.6%, 43.3%, 47.6% and 59.6% of HCV 1b, respectively. Fifteen frequent point mutations of NS5B gene in this group were determined, which caused I2682V and S2755N frequent mutations of NS5B protein. Conclusions The dominant genotypes of HCV epidemic in Liuzhou, Guangxi are 1b, 6a and 3a. Most of the subtypes of HCV 1b belong to the local genetic group. The NS5B proteins of this group have characteristic mutational sites and may affect the antiviral effect with direct antiviral drugs. -
Key words:
- Hepatitis C virus /
- Genotype /
- HCV 1b /
- NS5B region /
- Mutation
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表 1 2014―2018年柳州CHC患者感染HCV基因型分布
Table 1. HCV genotype distribution in CHC patients in Liuzhou from 2014 to 2018
年份 例数[n(%)] 1a 1b 2a/c 3a 3b 6a 6e/d NT 2014 6(3.6) 86(50.9) 0(0.0) 22(13.0) 7(4.1) 44(26.0) 4(2.4) 0(0.0) 2015 0(0.0) 14(35.9) 0(0.0) 2(5.13) 8(21.0) 11(28.2) 4(10.3) 0(0.0) 2016 2(2.9) 30(42.9) 1(1.4) 9(12.9) 4(5.7) 20(28.6) 3(4.3) 1(1.4) 2017 2(3.4) 21(35.6) 0(0.0) 11(18.6) 4(6.8) 20(33.9) 1(1.7) 0(0.0) 2018 6(4.4) 52(38.5) 1(0.7) 22(16.3) 10(7.4) 41(30.4) 3(2.2) 0(0.0) 合计 16(3.4) 203(43.0) 2(0.4) 66(14.0) 33(7.0) 136(28.8) 15(3.2) 1(0.2) -
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