Abstract: Objective To realize the gene mutation of Mycobacterium tuberculosis strains resisted with isoniazid,rifampicin,ethambutol an d streptomycin isolated from coal workers’ pneumoconiosis with tuberculosis in order to find more effective therapy and prevention methods.Methods 64 strains of isoniazid, rifampicin,streptomycin or eth ambutol resistant Mycobacterium tuberculosis were separa ted from 96 coal workers’ pneumoconiosis with tuberculosis. Then we amplified t heir katG, rpoB or rpsL fragments of genome with PCR and compared their SSCP pro files with standard strains.Results Out of 64 drug-resistant strains,42 rpsL,47 rpoB and 42 katG SSCP profiles appe ared abnormal separately.Conclusion Most of the resistant strai ns in our analyse showed evidences on gene mutation.The mutation rate was lower than that of rutinc test.

Key words: Tuberculosis,pulmonary, Tuberculosis,Multidrug-resis tant, M.tuberculosis, Genes,bacterial