安徽省391株结核分枝杆菌临床分离株MLVA基因分型研究  

Genotyping of Mycobacterium tuberculosis clinical strains isolated Anhui province with variable number tandem repeats

作　　者：王庆[1,2] 董海燕[3] 包训迪[1,2] 赵秀芹[3] 徐东芳[1,2] 万康林[3] 

机构地区：[1]安徽省结核病防治研究所 [2]安徽省胸科医院检验科,合肥230032 [3]中国疾病预防控制中心传染病预防控制所传染病预防控制国家重点实验室

出　　处：《中国防痨杂志》2013年第1期17-21,共5页Chinese Journal of Antituberculosis

基　　金："十一五"国家重大科技专项(2008ZX100/03-010-02);上海市结核病重点实验室开放基金(2009K03)

摘　　要：目的初步探讨安徽省结核分枝杆菌多位点可变数目串联重复序列分析(MLVA)的分型及分布特征。方法选取安徽省结核分枝杆菌391株临床分离菌株,常规培养、收集菌体,提取基因组DNA,采用聚合酶反应(PCR)对15个VNTR位点进行检测分析,基因分型聚类分析采用BioNumerics 5.0软件。结果经基因聚类分析,可分4个基因群(Ⅰ群、Ⅱ群、Ⅲ群和Ⅳ群),分别为Ⅰ群占3.32%(13/391),Ⅱ群占3.07%(12/391),Ⅲ群所占89.00%(348/391),Ⅳ群占4.60%(18/391);共含183个基因型,其中149株为独特类型,余242株分为34簇,其中最大的一簇包含64株(基因型为424343357333544);研究显示明显的基因多态性,Mtub21和MIRU26位点显示较高多态性(h),分别为0.591和0.527;ETR-B、ETR-C、ETR-D和MIRU23显示较低多态性,h分别为0.125、0.08、0.124和0.137;基因群分布与药敏间的差异无统计学意义(χ2值分别为0.22、0.00、0.01、0.07,P值均>0.05)。结论初步证实安徽省结核分枝杆菌菌株存在明显的基因多态性,以Ⅲ型菌株为主,应加强对此型菌株流行的监控。Objective To investigate the genotype distribution of Mycobacterium tuberculosis clinical isolates from Anhui province with the multiple-locus variable number tandem repeats analysis （MLVA）. Methods 391M. tuberculosis clinical isolates randomly selected from Anhui province were cultured in Lowenstein-lensen medium. The bacteria were collected, and then their genome DNAs were extracted. The polymorphism of 15 VNTR locus in the DNA samples was analyzed by PCR respectively. The clustering of genotype was analyzed with the software BioNumerics（Version 5.0）. Chi-square test was used for statistical analysis. Results The clustering analyses of genotype showed that 391 strains were categorized into 4 gene clusters （genogroup Ⅰ,Ⅱ,Ⅲ and Ⅳ）, in which 3.32%（13/391）was belong to genogroup Ⅰ, 3.07% （12/391）was genogroup Ⅱ, 89.00% （348/391） was genogroup Ⅲ, and 4. 60%（187391）was genogroup Ⅳ. The 391 strains were typed to 183 distinct MIRU patterns. 149 isolates were unique, 242 strains were grouped into 34 diferent MIRU dusters, in which the largest cluster was genotype 424343357333544 and included 64 strains. There were obvious polymorphisms of VNTRs in these strains, Mtub21 and MIRU26 were highly discriminative （h=0. 591 and 0. 527, respectively）, ETR-B, ETR-C, ETR-D and MIRU23 were poorly discriminative （h = 0. 125, 0.08, 0. 124 and 0. 137, respectively）. Distribution of genotypes was not significantly associated with the resistance to four drugs （the values of χ^2 were 0. 22, 0. 00, 0. 01, 0.07 respectively,P〉0. 05）. Conclusion M. tuberculosis clinical strains from Anhui province had obvious VNTR polymorphisms. There were at least 4 clusters of VNTR genotypes, and cluster type Ⅲ was predominant. The surveil lance on this type of M. tuberculosis needs to be strengthened.

关 键 词：分枝杆菌 结核 基因型 小卫星重复 

分 类 号：R440[医药卫生—诊断学]