7个VNTRs用于65株中国分离的结核分枝杆菌基因多态性研究

Study on genetic diversity of 65 Mycobacterium tuberculosis strains isolated in China based on 7 variable number of tandem DNA repeats

目的 应用数目可变串联重复位点 (variablenumberoftandemrepeats ,VNTRs)分子分型技术 ,初步探讨我国结核分枝杆菌的基因多态性特征。方法 采用PCR和琼脂糖凝胶电泳技术 ,对结核分枝杆菌的 11个数目可变重复位点进行检测 ,并应用Gel Proanalyzer 3.1软件和BioNumerics(Ver sion 3.0 )软件进行结果分析 ,分析结核分枝杆菌DNA多态性特征。结果 选取结核分枝杆菌基因组中的 7个 (ETR A、ETR B、ETR C、ETR D、ETR E、ETR F、MPTR A)具有明显多态性特征的串联重复位点 ,检测分析了 6 5株来自安徽、湖南和江苏省的结核分枝杆菌 ,结果显示被测菌株可分为 10个不同的基因型 ,其中以 2个型别为主 ,占总菌株数的 6 9.2 % ,其他菌株呈散在分布。结论 采用VNTR分型技术初步分析表明 ,中国结核分枝杆菌具有明显的基因多态性 ,且存在主要流行菌群。

Objective To study the character of genetic di ve rsity of Chinese Mycobacterium tuberculosis strains based on variable number of tandem repeats (VNTRs) in the total genome. Methods E leven tandem repeat loci in the total genome were analyzed by PCR and agarose ge l electrophoresis. The character of the polymorphism of DNA fingerprinting of M.tuberculosis was analyzed with Gel-Pro analyzer 3.1 software and BioNumeric s 3.0 software. Results Seven VNTR loci (ETR-A, ETR-B, ETR-C, ETR-D, ETR-E, ETR-F, MPTR-A) were chosen to analyze the 65 M.tuber culosis isolates from the patients with tuberculosis in Anhui, Hunan and Jiang su provinces and these strains were classified into 10 genotypes according to th eir characters of VNTRs. Sixty-nine percent of them belonges to two main types. Conclusion There is obvious length polymorphism in the M.tuberculosis isolates and implies that there perhaps exist epidemic strain clusters in M.tuberculosis in China. [