Comparison of gene expression profiles between high and low dose isoniazid resistance in multidrug resistant mycobacterium tuberculosis

Tuberculosis (TB) is one of the oldest serious infection disease in developing countries caused by Mycobacterium tuberculosis complex (MTBC). The aim of the current study is to see the effect of low (0.1 μg/ml) and high (0.4 μg/ml) doses of INH respectively on MDR and sensitive M. tuberculosis complex strains by investigating the expression levels on 18 efflux pump genes. polA was considered as a housekeeping gene to see the effectiveness of the drug in the two different doses in comparison with Pan-sensitive isolates. In addition to that to investigate the relation between the efflux pump genes expression levels and the mutations on four genes katG, rpoB, inhA and oxyR-ahpC on M. tuberculosis complex isolates. It was found that eight of the efflux pump genes Rv0849, Rv1634, mmpl 13a, mmpl 13b, stp, Rv3239c, emrB and Rv2994 were overexpressed in 100% of the isolates when comparing the three groups with the sensitive isolates, however there were no significant differences among these three groups, we also found that 100% of the isolates which have mutations on the genes rpoB, katG and inhA were overexpressed.