中国柯萨奇病毒A组2型的遗传进化分析

Phylogenetic analysis of coxsackievirus A2 in China

目的探讨中国柯萨奇病毒A组2型(coxsackievirus A2,CV-A2)毒株的遗传进化特征。方法收集中国CV-A2毒株的VP1区及全基因序列,采用MEGA 10.2.4软件构建系统进化树并开展氨基酸位点突变分析,采用SimPlot 3.5.1软件进行基因重组分析。结果共收集到118条VP1序列和26条全基因序列。CV-A2毒株主要来源于广东省,毒株数量自2011年开始迅速增多。基于VP1序列构建的进化树有7个分支,原型毒株为独立A组,多数CV-A2毒株聚集于G组。具有全基因组序列的CV-A2代表株的基因重组分析显示毒株间存在基因重组。另外,VP1氨基酸序列共有22个突变位点。结论中国流行的CV-A2毒株已发生较明显的基因重组和VP1区域氨基酸位点突变,监测CV-A2的演化对于手足口病的防控具有重要意义。

Objective To analyze the phylogenetic character of coxsackievirus A2(CV-A2)strains in China.Methods Sequences of the VP1 region and complete genomes of CV-A2 strains in China were collected.The phylogenetic tree and analysis of amino acid mutation were conducted by MEGA 10.2.4 software.The analysis of genetic recombination was carried out through SimPlot 3.5.1 software.Results A total of 118 sequences of CV-A2 VP1 were collected,and 26 strains had complete genome sequences.CV-A2 strains mainly originated from Guangdong Province.The number of CV-A2 strains had increased rapidly since 2011.Phylogenetic tree based on the VP1 region was clustered into seven distinct lineages,and the prototype strains were a separate lineage A while most of strains gathered in lineages G.The analysis of gene recombination of CV-A2 representative strains with complete genome sequences exhibited recombinant segments.The amino acid variations were found at 22 sites of VP1 protein.Conclusion CV-A2 strains circulating in China have undergone gene recombination and mutations in the amino acid sites of the VP1 region,suggesting that monitoring the evolution of CV-A2 is of great significance for the prevention and control of hand-foot-mouth disease.