124例耐多药结核分枝杆菌基因突变特征分析

目的对临床分离的耐多药结核分枝杆菌相关基因的突变特征进行分析。方法对124例耐多药结核分枝杆菌以及50株敏感株的耐药相关基因(包括异烟肼inh A、kat G、oxyR-ahp C间隔区以及利福平rpo B)进行序列测定,分析其基因突变情况。结果异烟肼耐药inh A基因突变率为14.5%;kat G基因突变率为70.2%(87/124),主要位于315位;oxyR-ahp C间隔区突变率为15.3%;inh A、kat G两种基因同时突变率75.0%,三种基因同时突变率为89.5%。利福平rpo B基因突变的检出率高达95.2%,突变主要发生在531、526、516位点。结论我省耐多药菌异烟肼耐药相关基因最常见突变为kat G 315、inh A C-T(-15)、axyR-ahp C间隔区(-10)C-T,利福平为rpo B531、526、516。结合MDR-TB耐药相关基因的特征分析,可以建立一种快速、准确、特异的适合于我省的检测结核菌耐多药性的新方法。

Analysis of characteristics of genetic mutation of 124 cases of multidrug-resistant mycobacterium tuberculosis

Objective To analyze gene mutation of mycobacterium tuberculosis. Methods The resistant genes of 124 cases of multi-drug resistant mycobacterium tuberculosis and 50 sensitive strains(including inhA, katG and oxyR-ahpC spacer of isoniazid, and rpoB of rifampicin)were given sequence determination to analyze the gene mutation. Results The gene mutation rate of inhA was 14. 5%, and 70. 2% for KatG(87/124), mainly at 315 site. The gene mutation rate of oxyR-ahpC spacer was 15. 3%, and inhA and katG at the same time for 75. 0%. The mutation rate of the three genes at the same time was 89. 5%. The gene mutation rate of rpoB of rifampicin was 95. 2%, and mutation occurred mainly at 531, 526, 516 sites. Conclusion The most common mutation of multi-drug resistant isoniazid genes in our province are katG 315, inhA C-T(-15), oxyR-ahpC spacer(-10)C-T, and that of rifampicin is rpoB531, 526, 516. The analysis of combining the feature of MDR-TB resistance related gene can establish a rapid, accurate, specific and suitable new method to detect multi-drug resistant tuberculosis.