天津地区肠道病毒71型的分子特征分析

Molecular characterization of enterovirus 71 strain isolated in Tianjin

目的：分析天津地区手足口病（Hand-Foot-Mouth Disease,HFMD）肠道病毒71型分离株（Enterovirus 71,EV71）的分子特征。方法：从2008年手足口病患者标本中分离EV71病毒,随机挑取12株并结合09年4个阳性标本经RT-PCR扩增VP1区,并进行核苷酸序列分析。结果：16株EV71与C4亚型代表株具有较高的核苷酸序列同源性,同源性在91.5%－93.5%。在亲缘性关系树上,其与C4亚型代表株处于同一分支,属于C4基因亚型。结论：近两年天津地区HFMD的主要流行株为EV71 C4亚型,在进化树中形成紧密相连的三簇,处于不同的进化链中,提示天津地区可能存在多个传播链,应加强对引起HFMD的EV71的分子流行病学监测。

Objective：To explore the molecular characteristics of the VP1 coding fragment from EV71 strains that isolated in Tianjin. Methods ：The strains of virus were isolated by cell culture, 12 isolated strains as well as 4 positive specimen were selected for sequencing of complete VP1 coding gene and analyzed by software. Results：The VP1 -based analysis indicated that the strains detected from Tianjin formed a distinct cluster in subgenotype CA, having 91.5% to 93.5% nucleotide sequence identities. They also clustered with reference strains of C4 subgenotype in the phylogenetic tree. Conclusion ： The CA subgenotype of EV71 is one of the important pathogens of HFMD in Tianjin. The 16 specimen in this study cluster three close together in our phylogenetic analysis, suggesting that there may be several transferchains in Tianjin, but we still need to get more molecular epidemiologic data.