Mutations in the rpoB Gene of Multidrug-Resistant Mycobacterium tuberculosis Clinical Isolates from India

Mutations in the 81-bp rifampin resistance-determining region (RRDR) of the rpoB gene were analyzed by DNA sequencing of 50 Mycobacterium tuberculosis clinical isolates (44 resistant and 6 sensitive) from various parts of India. Fifty-three mutations of 18 different kinds, 17 point mutations and one deletion, were observed in 43 of 44 resistant isolates. Three novel mutations and three new alleles within the RRDR, along with two novel mutations outside the RRDR, are reported in this study.