贵州及周边省市狂犬病病毒的分群和进化研究

目的 全面掌握贵州及周边省市狂犬病病毒(RABV)的遗传进化特征和分群特点,了解狂犬病疫苗株与流行株的分子遗传差异,为贵州狂犬病疫情的预防和控制提供指导依据.方法 搜索GenBank数据库中贵州及周边5个省市具有明确时间、地区及宿主信息的流行毒株,对其糖蛋白基因(G)全序列进行汇总,并结合本实验室获得的贵州毒株和国内现役疫苗株G序列,利用MEGA和BEAST软件分别进行系统进化和时间进化分析.结果 贵州及周边省市79株RABV均属于基因1型,9个类群的RABV流行株具有明显的地域特征,11株疫苗株分化为2个类群;RABV流行株与疫苗株G基因核苷酸和氨基酸同源性分别为0.827～0.999和0.713～0.998;贵州及周边省市RABV流行毒株的最近共同祖先(TMRCA)可追溯至150年前.结论 贵州及周边省市流行的RABV优势毒株群仍属于基因1型,但毒株经过多年流行已经出现了分化,有必要对流行毒株与疫苗株的遗传变异一致性进行深入研究.

Classification and evolution of rabies virus in Guizhou and neighboring provinces and cities

Objective To understand the classification and evolution of rabies virus (RABV) in Guizhou and its neighboring provinces and cities,as well as molecular genetic differences of rabies vaccine strains and epidemic strains,so as to provide guidance for the prevention and control of rabies epidemic situation in Guizhou.Methods Epidemic strains with clear information of time,location and host from Guizhou and its 5 neighboring provinces and cities were searched in GenBank,then the glycoprotein (G) gene complete sequences were summarized.Combining with G gene complete sequences of epidemic and vaccine stains obtained from our laboratory,the phylogenetic analysis and evolutionary time analysis were conducted by MEGA and BEAST software,respectively.Results The analysis indicated that 79 RABV strains from Guizhou and its neighboring provinces and cities belonged to Genotype 1.All epidemic strains could be classified as 9 different geographical groups which had obvious regional characteristics,and 11 vaccine strains were classified as 2 groups.The nucleotide and amino acid homology of G gene for epidemic and vaccine strains were 0.827-0.999 and 0.713-0.998,respectively.It was estimated that time to the most recent common ancestor(TMRCA) of RABV strains from Guizhou and its neighboring provinces and cities was detected about 150 year ago.Conclusions RABV genotype 1 is predominant in Guizhou and its neighboring provinces and cities.However,the strain has differentiated after years of evolution.It is necessary to further reassess the consistency and effectiveness of the RABV epidemic strains and vaccine strains.