新疆鼠疫菌株多位点可变数目串联重复序列基因分型研究

MLVA genotyping of Yersinia pestis isolates from natural foci in Xinjiang,China

目的应用多位点可变数目串联重复序列基因分型方法,对新疆维吾尔自治区(新疆)4个类型鼠疫自然疫源地鼠疫耶尔森菌(鼠疫菌)分离株进行基因分型研究,探析新疆分离株与我国其他鼠疫疫源地分离株之间的遗传进化关系。方法收集2015-2019年新疆4个类型鼠疫自然疫源地18株分离株,提取鼠疫菌基因组DNA,采用多位点可变数目串联重复序列分析(MLVA)(14+12 VNTR位点)技术、多色毛细管电泳方法进行基因分型,运用BioNumerics 7.6软件对基因分型结果进行聚类分析。结果 18株鼠疫分离株被14位点MLVA分为3个群、12个基因型;被14+12位点MLVA分为3个群、15个基因型,且同类型鼠疫自然疫源地分离株聚为一个分支。不同时期、同类型鼠疫自然疫源地的分离株亲缘关系较近,基因型存在明显的地区聚集性,遗传性相对稳定。结论新疆4个类型鼠疫自然疫源地分离株基因型呈多态性,遗传性相对稳定;MLVA分型方法适宜新疆鼠疫分离株遗传进化与溯源研究。

Objective To study the genotypes of Yersinia pestis isolated from four types of the plague natural foci in Xinjiang Uygur Autonomous Region(Xinjiang), China by multiple-locus variable-number tandem repeat analysis(MLVA), and to investigate the genetic and evolutionary relationship of the isolates between Xinjiang and other plague natural foci in China. Methods The genomic DNA of 18 Y. pestis isolates from four types of natural foci in Xinjiang from 2015 to 2019 was extracted. MLVA(14+12 VNTRs) and multicolor capillary electrophoresis were used for genotyping, and the BioNumerics 7.6 software was used for cluster analysis. Results The 18 isolates were divided into three groups with 12 genotypes by MLVA 14, and three groups with 15 genotypes by MLVA 14+12. The isolates from the foci of the same type could be clustered into one branch, and the isolates from the same type of foci in different periods had close genetic relationship, with obvious regional clustering of genotypes, exhibiting relatively high genetic stability.Conclusion MLVA analysis shows polymorphism in Y. pestis isolates from four types of the natural foci in Xinjiang,with relatively high genetic stability. MLVA typing is suitable for the phylogenetic and traceable study of Y. pestis isolates in Xinjiang.