2009年广东省肠道病毒71型vp1区全序列分析

目的研究广东省2009年肠道病毒71型的基因特征及流行趋势。方法收集广东省各地市手足口病病例的粪便、肛拭子、咽拭子、疱疹液和脑脊液等肠道病毒71型核酸阳性标本进行病毒分离及鉴定,选取粤东、粤西、粤北、珠三角4个地区16例病例的16株代表株进行vp1区全序列片段扩增,并运用DNASTAR 6和MEGA 4.02软件,将16株代表株的vp1全序列与从GenBank中下载的肠道病毒71型各代表基因型（亚型）进行同源性分析,并构建系统发生树。结果所选16株代表株经vp1区全序列片段扩增,扩增片段长度为1 042 bp,经测序和拼接后获得的序列片段长度为891 bp。16株代表株与肠道病毒71型A型和B型的亲缘性较远,核苷酸和氨基酸的同源性分别在81.5%～84.6%和94.3%～97.0%之间;与C型的亲缘性较近,核苷酸和氨基酸的同源性分别在87.4%～93.5%和97.6%～99.3%之间,其中与C4亚型的亲缘性最近,核苷酸和氨基酸的同源性分别在92.5%～93.5%和98.3%～99.3%之间。构建系统发生树表明,该16株代表株与国内外C4亚型处于同一簇,属肠道病毒71型的C4基因亚型C4 a群。结论广东省2009年肠道病毒71型的流行株属于C4亚型,为C4亚型的C4 a群,且全省范围内均有流行。

Entire vp1 nucleotide sequences of enterovirus 71 isolated from patients with hand-foot-mouth disease in Guangdong Province,2009

Objective To study the gene characterization and the epidemic tendency of enterovirus 71（EV71） in 2009 in Guangdong Province.Methods The EV71 positive samples including throat swabs,herpes fluid,anal swabs,feces,and cerebrospinal fluid from patients with hand-foot-mouth disease（HFMD） in Guangdong Province were collected for virus isolation and identification.EV71 strains isolated from samples were amplified for the entire vp1.The phylogenetic analysis between strains isolated and those downloaded from GeneBank was done by using the software DNASTAR 6 and MEGA 4.02.Results Sixteen EV71 strains were selected.The length of the fragment was 1 042bp,and the full length of vp1 sequence was 891bp.The nucleotide and the amino acid identity of the sixteen strains with the reference strains of type A and type B were 81.5%-84.6% and 94.3%-97.0%,respectively,which indicates that the relationship between them were relatively farther.The nucleotide and the amino acid identity of the sixteen strains with the reference strain of type C were 87.4%-93.5% and 97.6%-99.3%,indicating there was an closer relationship between them.The nucleotide and the amino acid identity of the sixteen strains with the reference strain of C4 subtype were 92.5%-93.5% and 98.3%-99.3% respectively,indicating their relationship was nearest.The phylogenetic tree based on vp1 gene constructed from the selected strains and other EV71 reference strains showed that they were all located in the same cluster,which suggested that the selected strains belonged to the C4a cluster of C4 subtype of EV71.Conclusion The EV71 isolated from HFMD-patients in Guangdong Province belonged to the C4a cluster of C4 subtype of EV71,which was the prominent epidemic strain all over the province.