用IS6110限制性片段长度多态性方法分析中国南方部队结核分支杆菌DNA指纹特征

目的：分析南方部队结核病患者和当地患者中结核分支杆菌分离株DNA指纹特征，探讨南方部队结核病的分子流行病学特征。方法：用限制性内切酶PvuⅡ消化结核分支杆菌DNA，后用琼脂糖凝胶电泳，再用Southern免疫转印，用[α^32P]-dCTP标记的DNA IS6110序列中的245bp片段作探针，进行杂交后得到限制性片段长度多态性图谱，结合一般流行病学资料加以分析比较。结果：共检测185株结核分支杆菌分离株。检测菌株的IS6110拷贝数范围为1～22。部队患者和当地患者的IS6110拷贝数分布差异无显著姓。部队患者结核菌分离株的IS6110拷贝数主要集中在6～20个，当地分离株主要集中在7～20个；全部菌株指纹特征分成8个组，部队分离株和当地分离株均主要集中在Ⅰ、Ⅱ、Ⅲ 3个组里。耐药菌株指纹特征在各组中的分布与敏感菌株差异有显著性；患者是否接种卡介苗在各组中的分布差异无显著性。结论：南方部队患者与当地患者结核菌分离株在遗传关系上较接近，在基因水平上相关程度较强。提示部队结核病的发生与当地结核分支杆菌菌株的传播密切相关。

Study on DNA fingerprinting of Mycobacterium tuberculosis strains isolated in Southern Chinese army by IS6110-restriction fragment length polymorphism

OBJECTIVE: To study the correlation between DNA fingerprinting of Mycobacterium tuberculosis (MTB) stains isolated from the Chinese army in the south and from local residents, and to investigate the molecular epidemiological characteristics of tuberculosis (TB) in the army, for the sake of TB prevention in the army. METHODS: MTB DNA was digested with restriction endonuclease PvuII and electrophoresed in agarose gel, after Southern Blotting, the membrane was hybridized with a 245 bp fragment of IS6110 which labeled [alpha(32)P]-dCTP as probe. Finally, a restriction fragment length polymorphism (RFLP) patterns was shown, and analyzed logestic with epidemiological data from the patients. RESULTS: A total number of 185 TB strains were detected and the IS6110 copy numbers ranged from 1 - 22. No significant difference was found in the IS6110 copy numbers between patients from army and local patients. IS6110 copy numbers of TB strains in army patients were centered in 6 - 20, however, with 7 - 20 copies in local TB patients. The TB strains were dispersed into 8 groups and the majority of TB strains in both army and local patients was centered in groups I, II, III. The distribution of DNA fingerprint for drug resistance TB strains was significantly different from those for sensitive strains. No different distribution of among groups was found regarding BCG history. CONCLUSIONS: The genetics of TB stains were roughly the same between the army patients and local ones, but there was a strong correlation in the gene levels. Data suggested that a close connection should be considered on TB prevention and treatment for TB patients in the army and local residents.