分枝杆菌散在重复单位对结核分枝杆菌分型的研究

The application of mycobacterial interspersed repetitive unit(MIRU) in M.tuberculosis genotying

目的评价分枝杆菌散在重复单位(MIRU)分型方法在结核病流行病学上的应用,探讨该方法的应用前景。方法采用MIRU分型对158株结核分枝杆菌进行基因分型,这些菌株均已进行IS6110-RFLP分型。结果MIRU分型结果产生只需1d。158株结核分枝杆菌共产生105个类型,其中65个为独特类型。在MIRU的12个区中,重复区4、10、26、40具有较高的多态性。用Hunter-Gaston Index(HGI)对2种方法进行评价,IS6110-RFLP的分辨指数为99.4%,MIRU技术的分辨指数为97.8%。当IS6110拷贝数小于等于10个时,IS6110-RFLP的分辨指数为98%,MI-RU的分辨指数达到98.2%。结论MIRU分型方法具有快速、简便、分辨力较高的特点,便于普及,可在结核病分子流行病学研究中发挥重要作用。

Objective To assess the application of mycobacterial interspersed repetitive unit （MIRU） in the epidemiology of tuberculosis, and to discuss its prospect. Method 158 Mycobacterium tuberculosis isolates that had been typed by IS6110-RFLP were subjected to MIRU. Results The results were obtained by MIRU within 1 day. 105 patterns were produced, in which 65 patterns were unique. In MIRU loci, there were four loci（loci 4,10,26,40） with higher diversity. MIRU typing provided discrimination （Hunter-Gaston Index [HGI] of 0. 978） compared with the IS6110 RFLP method （HGI=0. 994）. For those strains lower than 10 copies, MIRU typing provided discrimination （HGI=0. 982） comparable to that of the RFLP method （HGI=0. 98）. Conclusion MIRU typing, which is simple, rapid, and easy to popularize, would exert important function in the epidemiological investigation of tuberculosis.