IS6110-限制性片段长度多态性DNA分型在结核分子流行病学研究中的应用

目的 建立宁夏、北京和上海等地结核分支杆菌发离株IS6110－RFLP DNA指纹图谱，观察其流行病学特征。方法 提取结核分支杆菌基因组DNA，经限制性内切酶PvuⅡ切割、琼脂糖凝胶电泳和Southern转印后，用荧光标记的IS6110DNA序列中245bp探针杂交，以核酸化学发光试剂盒探测荧光信号，比较各菌株指 IS6110拷贝数和带型，分析不同地理区域流行菌株的特点。结果 103例结核患的临床分离株，经245bp探针杂交后的指纹图谱显示大部分菌株含8－21个IS6110拷贝，在宁夏和北京地区流行的结核分支杆菌带型具有共同特点，并有成簇分布的现象，在上海分离株中发现1株零拷贝株和1株单拷贝株。结论 IS6110－RFLP DNA分型方法可用于我国流行的结核分支杆菌分子流行病学研究；宁夏分离株与北京分离株在基因上亲缘关系较相近。

IS61 10-restriction fragment length polymorphism based DNA fingerpr inting in molecular epidemiology of tuberculosis

OBJECTIVE: To identify the IS6110-restriction fragment length polymorphism (RFLP) DNA fingerprinting patterns of some clinical isolates of Mycobacterium tuberculosis (MTB) isolated from Ningxia, Beijing and Shanghai in recent years, and to observe their epidemiological characteristics. METHODS: Chromosomal DNA of MTB was digested with endonuclease PvuII, then electrophoresed on agarose gel plate and transferred capillarilly to a nylon filter and hybridized with 245 bp fragment of IS6110 which labeled using random primer fluorescein labeling kit. The RFLP patterns of Southern hybridization were inspected autofluorographically and the chromosomal DNAs of MTB were thereby typed. RESULTS: Most of 103 isolates of MTB shared 8 approximately 21 copies. Some of them were clustered. Strains isolated from Ningxia and Beijing had similar DNA fingerprinting patterns. One zero copy strain and one single copy strain were found among isolates from Shanghai. CONCLUSIONS: IS6110-RFLP based typing is feasible for MTB molecular epidemiological study in China. Most of isolates of MTB show analyzable patterns. Isolates of MTB from Ningxia and Beijing have close genomic relation.