Mutations of rpoB gene in multi-drug resistant Mycobacterium tuberculosis isolates from Fujian province

Objective:To analyze the mutation characteristics of rpoB gene in multi-drug resistant(MDR) Mycobacterium tuberculosis isolates in Fujian province,and provide molecular evidence for fast diagnosis of multi-drug resistant tuberculosis. Methods:Seventy-five MDR M. tuberculosis isolates and 10 pan-susceptible isolates were selected from 30 survey sites,and the mutation patterns including RRDR in rpoB gene of these strains were detected by PCR and sequenced with H37Rv as control. Results:No mutation was detected in 10 pan-susceptible isolates. In 75 MDR M. tuberculosis isolates,the mutation rate of rpoB gene was 96. 0%(72 /75),mainly in RRDR region(94. 7%,71 /75). It was found 15 types of mutations,including 12 point mutations and 3 combination mutations,involving 9 sites in RRDR region and 1 site not(locus 569). The most frequent mutation sites in MDR M. tuberculosis isolates from Fujian province were codon531,codon526 and codon516,with total mutation rate of 84. 0%(63/75). Conclusion:The rapid diagnosis method for RFP drug resistance of MDR M. tuberculosis could be based on the 3 loci mutation characteristics