目的　研究重庆地区结核分支杆菌对利福平 (R)的耐受与rpoB基因突变的关系。方法　PCR扩增 6 7株分离自重庆地区肺结核患者的耐R结核分支杆菌的rpoB基因片段 (319bp) ;测定扩增片段的序列 ,并与野型株序列作对比分析。 结果　 6 7株临床分离的耐R株中 ,8株 (12 % )无变异 ,5 9株 (88% )有突变 ,突变涉及 8个氨基酸位点。突变有 14种类型 ,4 9株(83% )的突变为单个密码子取代 ,9株为双密码子取代 ,1株为 3个碱基 (一个密码子 )插入 ,未检出碱基缺失。突变高发位点为 5 31位 (37/ 5 9)密码子 ,其次为 5 16位 (13/ 5 9)和 5 2 6位 (7/ 5 9)。 3株菌在 4 77位的谷氨酸 (Glu) ,天冬氨酸 (Asp)突变为首次发现。结论　重庆地区结核分支杆菌耐利福平的发生与rpoB基因的突变密切相关 ,突变的类型与国外的报告基本相似。PCR扩增和产物测序将是临床检测结核分支杆菌耐利福平和耐多药的一种迅速、准确的方法 Objective To study the relationship between rifampin (R) tolerance and rpoB gene mutation in Mycobacterium tuberculosis in Chongqing area. Methods The rpoB gene fragment (319 bp) of 6 7 Mycobacterium tuberculosis strains isolated from patients with pulmonary tuberculosis in Chongqing area was amplified by PCR. The sequence of the amplified fragment was determined and compared with the wild-type strain sequence. Results Of the 67 R strains isolated from clinical isolates, 8 (12%) showed no mutation, 59 (88%) had mutations and 8 mutations were involved in the mutation. There were 14 types of mutations, of which 49 (83%) were single-codon substitutions, 9 were double-codon substitutions, and 1 was 3-base (one codon) insertions and no base deletions were detected. There were 5 31 (37/59) codons for the high incidence of mutations, followed by 5 16 (13/59) and 526 (7/59). The first three mutations were found in the mutants of glutamic acid (Glu) and aspartic acid (Asp) at position 4 77. Conclusion The occurrence of rifampin in Mycobacterium tuberculosis in Chongqing is closely related to the mutation of rpoB gene. The type of mutation is basically similar to that reported in foreign countries. PCR amplification and product sequencing will be a rapid and accurate method for the clinical detection of Mycobacterium tuberculosis ritonifampin and multidrug resistance