Objective: To analyze the characteristics of embB gene mutation in ethambutol-resistant Mycobacterium tuberculosis (M. TB) strains isolated from patients in Xi'an for establishing a rapid method to detect the mutation of embB gene in M. TB.
Methods: The embB gene of 104 Mycobacterium tuberculosis isolates was detected by PCR-Single Strand Conformation Polymorphism (PCR-SSCP) and PCR-Restriction Fragment Length Polymorphism (PCR-RFLP).
Results: Taking strain H37Rv as a control, the SSCP and RFLP profiles of embB of 35 drug-sensitive strains in 104 Mycobacterium tuberculosis isolates were normal. The display of SSCP profiles in 39 of 69 (56.52%) ethambutol-resistant isolates and the display of RFLP profiles in 19 of 69 (27.54%) ethambutol-resistant isolates were abnormal.
Conclusion: The EMB-resistance of M. TB strains isolated from patients in Xi'an is related to the mutation of embB gene, PCR-SSCP and PCR-RFLP are sensitive methods for detecting ethambutol-resistance of M. tuberculosis.