吉林省110株结核分枝杆菌临床分离株MLVA基因分型

MLVA analysis of 110 clinical isolates of Mycobacterium tuberculosis from Jilin Province

目的:利用多位点可变数目串联重复序列(MLVA)分型技术,了解近期吉林省结核分枝杆菌临床分离株基因型分布情况。方法:收集分离自吉林省2011—2012年不同市县来源患者标本的结核分枝杆菌分离株,提取基因组DNA,对12个数目可变串联重复序列(VNTR)位点进行扩增和产物电泳分析,使用Totalab软件对电泳条带进行数据化分析,使用BioNumerics(6.0)软件获得聚类分析结果。结果:对110株结核分枝杆菌临床分离株的12个VNTR位点进行检测,结果显示这些菌株有明显的多态性。12个VNTR位点中Hunter-Gaston指数能达到0.5以上的VNTR位点有9个,位点分辨能力最高的是MIRU26,最低的是MIRU20。基于12个位点的聚类分析,110株分离株可分为6个基因型群,其中分布最多是5群,占34%;其次是1群,占15%。分布最多的5群主要流行于吉林省通化市和松原市等地区。结论:吉林省流行的菌株存在着明显的遗传多态性;不同市县分布的主要基因型群存在差异,表明吉林省内不同地区结核分枝杆菌基因型的流行趋势不同。

Objective To analyze the genotypes of clinical isolates of Mycobacterium tuberculosis in Jilin Province with multiple locus variable numbers of tandem repeats（MLVA）genotyping.Methods Mycobacterium tuberculosis strains were isolated from patient samples in Jilin Province.Genomic DNA was extracted and 12 variable numbers of tandem repeats（VNTR） loci were amplified.The gels were analyzed by Totalab software and the results were clustered with BioNumerics（6.0）.Results Analysis of a total of 110 isolates with the 12 VNTR loci showed great genetic polymorphism in these isolates.Nine of the 12 loci showed the Hunter-Gaston index（HGI） were higher than 0.5.The clustering results showed that total of 6 genotype groups could be defined,of which group 5 was the most represent one,accounting for 34% of the isolates.The less represented genotypes included group 1,accounting for 15%.Strains of group 5 mainly distributed in Tonghua and Songyuan.Conclusion Mycobacterium tuberculosis isolates in Jilin Province shows great genetic polymorphisms.Different cities have different genotype profiles.