2015—2016年新疆EV71VP1区基因特征分析

Analysis of genetic characteristics of EV71 VP1 region in Xinjiang, 2015—2016

目的分析并掌握2015—2016年新疆引起手足口病的EV71毒株的基因特征。方法收集2015年和2016年新疆各地(州)手足口病临床样本,从EV71阳性样本中随机抽取56份(2015年和2016年各28份),扩增VP1区基因并进行序列测定,用Chromas Pro 1.7.6,Bio Edit 7.1.9及MEGA 5.05等软件分析序列。结果共获得51株毒株的VP1区基因序列,新疆株之间核苷酸序列同源性为93.5%~100.0%,EV71新疆株与EV71 C4a基因亚型代表株同源性最高,为95.4%~97.9%,与EV71 C4b基因亚型代表株同源性为90.0%~93.2%,与EV71原型株之间同源性仅为81.9%~83.6%;多数2015年新疆株与2014年深圳株(SHZH2014JB141330327)及2015年福建株(FJQZ246/CHN/2015)亲缘关系较近,核苷酸同源性为97.6%~99.2%;多数2016年毒株与2016年北京株(BJ2016/5XCHFM-155)亲缘关系更近,核苷酸序列同源性为98.7%~99.5%。结论 2015年和2016年EV71新疆株均属于C4a基因亚型,相互之间同源性较高,与国内其他地区同时期毒株关系较近;2015年与2016年EV71新疆株在进化树上有分别归属两支的趋势。

Objective To analyze and master the genetic characteristic of hand, foot and mouth disease（HFMD）-associated enterovirus A 71（EV-A71） in Xinjiang, 2015—2016. Methods Samples of clinical HFMD patients were collected from all prefectures of Xinjiang. Fifty-six EV-A71 positive samples were collected randomly. Reverse transcription polymerase chain reaction（RT-PCR） was taken to amplify the VP1 gene. The products of RT-PCR were sequenced, and then genotype identification and genetic characteristics analysis were performed by bioinformatics software Chromas Pro 1.7.6, Bio Edit7.1.9 and MEGA 5.05. Results Fifty-one strains of EV-A71 VP1 gene sequences were obtained, and all of them belonged to C4 a subgenotype. The Xinjiang EV-A71 strains shared 93.5%-100.0% homology of nucleotide sequence with each other,shared the highest homology of 95.4%-97.9% with that of EV-A71 C4 a subgenotype, 90.0%-93.2% with C4 b, and only81.9%-83.6% with EV-A71 prototype strain. Most Xinjiang strains in 2015 had closer relationship with the Shenzhen strain（SHZH2014JB141330327） and the Fujian strain（FJQZ246/CHN/2015）, which shared 97.6%-99.2% homology of nucleotide sequence. Most Xinjiang strains in 2016 had closer relationship with the Beijing strain（BJ2016/5XCHFM-155）, which shared 98.7%-99.5% homology of nucleotide sequence. Conclusions Xinjiang HFMD-associated EV-A71 strains share higher homology of nucleotide sequence with each other. Most of them have closer relationship with those strains at the same time period in other provinces. Strains in 2015 and strains in 2016 had a tendency to belong to two separate subbranches inthe phylogenetic tree.