Genotypic Analysis of Multidrug-Resistant Mycobacterium tuberculosis Isolates Recovered From Central China.

DNA sequencing analysis was used to investigate genetic alterations in therpoB, katG, andinhAregulatory region andembBin 66Mycobacterium tuberculosisisolates recovered from Central China. Of the 36 multidrug-resistant isolates, 33 (92%) had mutations in the amplified region ofrpoB. The most frequent mutation (58%, 19/36) was S531L (TCG→TTG). At least one mutation was found in thekatGandinhAregulatory region in 83% (30/36) of the multidrug-resistant isolates, and mutations atkatGcodon 315 were identified in 78% (28/36). Alterations atembB306 may not confer resistance to EMB, andembB306 mutants were more frequently accompanied byrpoBmutations (100%, 16/16) than bykatG315 mutations (75%, 12/16). Our results show that geographic variation in the molecular genetic mechanism is responsible for drug resistance in multidrug-resistantM. tuberculosis. This observation will facilitate the development of a rapid molecular drug resistance screening approach for drug-resistantM. tuberculosis. [ABSTRACT FROM AUTHOR]