Study on rpoB gene mutations in Mycobacterium tuberculosis

  Objective   To understand rpoB gene mutaions in rifampin(RIF)-resistant Mycobacterium tuberculosis(M.TB)strains isolated from tuber culosis(TB)patients in rural area and to provide genetic evidence for TB control in rural areas.

  Methods   145 isolates from two counties were examined for rpoB gene mutations by the polymerase chain reaction single strand conformation polymorphism(PCR-SSCP)method compared with virulent M.TB H₃₇R_v.

  Results   The prevalence of rpoB gene mutation was 71.4% in RIF-resistantor multidrug resistant M.TB from patients in this rural area.rpoB gene mutations were not found in all the 117 susceptible strains.In comparison with drug suscept ibility test results the sensitivity and specificity of PCR-SSCp assay were 71.4% and 100%, respectively.

  Conclusion   RIF-resistance of M.TB is strongly related to rpoB gene mutations.PCR-SSCP assay can detect rpoB gene mutations of RIF-resistant M.TB.It may thus be helpful to include a rapid detection of drug resistance of M.TB in resistance containment.