我国部分省市手足口病EV71 VP1基因特征分析

摘要:目的　分析我国部分省市手足口病EV71 VP1基因特征。方法　对从NCBI 上获得我国部分省市和本实验室来源的VP1 基因序列99株进行分析，采用MEGA软件构建系统进化树，计算相同或不同基因型及基因亚型毒株的核苷酸与氨基酸的相似性。结果　研究序列中C4亚型占96.0%，A亚型（3.0%）和B5亚型（1.0%）较少；A亚型毒株氨基酸变异为非同义突变；部分毒株发生氨基酸突变位点与病毒致病力相关；南方株相对北方株基因序列变异较大，东部株相对中部和西部株基因序列变异较大。结论　我国EV71以C4亚型为主；南方株较北方株、东部株较中西部株基因序列变异较大可能与我国气候、交通和人口流动有关；我国A亚型毒株非同义突变及2011年分离自浙江的KF358275突变位点增多是否会引起新的流行需加强后续监测。

Analysis of the genetic characteristics of EV71 VP1 in hand-foot-and-mouth disease in certain provinces and cities of China

Abstract: Objective The objective of the study was to analyze the genetic characteristics of EV71 VP1 in hand-foot-and-mouth disease (HFMD) in certain provinces and cities of China. Methods Gene sequences of VP1 in 99 strains of EV71 from certain provinces and cities of China and our laboratory were obtained from NCBI and analyzed by the MEGA software to establish a phylogenetic tree and to determine the similarity of nucleotides and amino acids between viral strains with identical or different genotypes or subtypes. Results Subtype C4 accounted for 96.0% of the studied sequences, while Subtype A (3.0%) and B5 (1.0%) occurred less frequently. Amino acids variation in Subtype A was non-synonymous mutation. Sites of amino acid mutation in some viral strains were correlated with viral pathogenicity. Strains from the South had greater gene sequence variation than those from the North, and strains from the East had greater gene sequence variation than those from the West and central China. Conclusion C4 is the main subtype of EV71 in China. Strains from the South, as compared with those from the North, and strains from the East, as compared with those from the Midwest, have greater gene sequence variations, which may relate to the climate, traffic, and population flow in China. Follow-up surveillance is required to monitor whether the non-synonymous mutations in Subtype A and the increasing mutation sites of KF358275 isolated from Zhejiang in 2011 would lead to new HFMD outbreaks.