结核分枝杆菌异烟肼耐药基因的研究

Study on the isoniazid- resistant gene in mycobacterrium tuerculosis

目的：探讨结核分枝杆菌异烟肼（INH）耐药与KatG基因突变和缺失的关系。方法：采用聚合酶链反应-单链构象多态性分析（PCR－SSCP）技术对结核分枝杆菌临床分离株的KatG基因进行分析。结果：28株INH敏感株KatG基因全部扩增阳性，其中1株（3．6％）SSCP泳动异常；30株INH耐药株中，3株（10．0％）KatG扩增阴性，27株KatG扩增阳性，其中20株（74．1％）SSCP泳动异常。与传统药敏试验相比，本法检测INH耐药的敏感性为76．7％，特异性为96．4％。结论：KatG基因突变和缺失可能是INH耐药的重要分子机理，PCR—SSCP有助于KatG基因的快速检测。

To investigate the relationship between isoniazid- resistance and Kat G gene mutation or deletion. Methods: Analyzing the Kat G gene in clinical isolates of M. tuberculosis by polymerase chainreaction and single- strand conformation ploymerphism (PCR- SSCP). Results: The kat G gene in 28 isoniazid - susceptible isolates was all positive, in 1 of 28 strains(3. 6 % )Kat G gene showed differences in the SSCPprofiles. Of 30 isoniazid - resistant isolates, 3Kat G gene (10. 0 % ) were not amplified, 20 (74. 1 % ) Kat Gshowed difference in the SSCP profiles. In comparison with conventional susceptibility testing method, the sensitivity and specificity was 76. 7 % and 96. 4 % respectively by PCR - SSCP method for detecting isoniazid- resistance. Conclusions: The mutation and deletion in Kat G gene was one of the important michanisms of isoniazid- resistance in M. tuberculosis, and PCR- SSCP technique could be helpful to rapid detection for Kat Ggene.