四川省德阳市柯萨奇病毒A组4型基因特征分析

Genetic Characterization of Coxsackievirus A4 in Deyang City,Sichuan Province

目的分析四川省德阳市柯萨奇病毒A组4型(coxsackievirus A4,CV-A4)的基因特征。方法对2014-2015年德阳市手足口病咽拭子标本进行病毒分离和核苷酸测序,VP1区序列与世界各地的CV-A4参考株序列构建进化树并分析基因特征。结果德阳市5株CV-A4分离株之间,VP1区核苷酸序列一致性91.5%~96.8%(推导氨基酸序列一致性97.7%~99.3%);同CV-A4原型株(High Point)比较,核苷酸序列一致性≥84.0%(推导氨基酸序列一致性≥97.0%);进化树分析显示,德阳市CV-A4分离株均为G1B基因亚型,分别与云南、上海和浙江分离株有较近的亲缘关系。G1B基因亚型内的平均核苷酸遗传距离为10.4%。结论德阳市CV-A4为G1B基因亚型,为中国大陆的优势基因亚型;VP1区核苷酸变异较大,形成不同的进化分支并在德阳市循环传播。

Objective To analyze genetic characteristics of coxsackievirus A4(CV-A4)in Deyang city.Methods Virus isolation was performed on throat swab specimens collected from patients with handfoot-mouth disease(HFMD)in 2014 and 2015,nucleotide sequencing and genetic characterization of Deyang CVA4 strains were carried out with other CV-A4 reference strains based on phylogenetic relationship of VP1 region.Results Of 5 Deyang CV-A4 strains,nucleotide(nt)and deduced amino acid(aa)sequence identities were 91.5%-96.8%and 97.7%-99.3%,respectively;compared with CVA4 prototype strain(High Point),nt and aa sequence identities were at least 84.0% and 97.0%,respectively.Phylogenetic analysis indicated Deyang strains pertained to G1 Bsubgenotype,and were most closely related to those strains isolated in Yunnan,Shanghai,and Zhejiang;mean genetic distance of nucleotide was 10.4% within G1 Bsubgenotype.ConclusionCV-A4 in Deyang City pertains to G1 B subgenotype that is dominant in China's Mainland.CVA-4 clusters on different phylogenetic branches and co-circulate in Deyang city.