Evaluation of Mycobacterium tuberculosis rpoB for detecting rifampicin resistance

The resistance mechanism of Mycobacterium tuberculosis to rifampicin (RIF) involves point mutation in the 81 bp region in the rpoB, namely, rifampicin resistance–determining region (RRDR). Mutations in these regions did not fully cause resistance to RIF. Therefore, a molecular rapid test would be less effective in diagnosing multidrug–resistant TB (MDR–TB). Here, we evaluated the rpoB of M. tuberculosis to obtain the variation and differentiation of its nucleotide sequences leading to MDR–TB. A total of 6,972 M. tuberculosis rpoB were identified in the NCBI, but only 200 data were considered eligible for analysis. Inclusion criteria were nucleotide bases determined through sequencing methods and isolated from human. We found that the polymorphic base of M. tuberculosis mutation–causing rpoB involved codons 413, 435, 451, 490, 511, 513, 516, 521, 522, 526, 530, 531 and 533. Phylogenetic tree analysis showed that mutation in the RRDR was a result of evolution in different geographical regions. This study could be used as a basis for rationally designing molecular tests to rapidly screen RIF resistance–related mutations that might contribute to MDR–TB control in Indonesia.