High-resolution melting facilitates mutation screening of rpsL gene associated with streptomycin resistance in Mycobacterium tuberculosis.

Drug resistance remains a serious threat to tuberculosis control worldwide. As one of the important first-line antitubercular agents, resistance to streptomycin (SM) and its derivatives has increased in recent years and has become one of the characteristics of extensively drug-resistant tuberculosis (XDR-TB). A novel rapid assay to screen for rpsL gene mutations associated with SM resistance in Mycobacterium tuberculosis (M. tuberculosis), was developed using high-resolution melting (HRM) analysis. The HRM results of 134 SM-resistant clinical isolates and 20 SM-susceptible clinical isolates of M. tuberculosis for rpsL gene mutations were perfectly matched with those of DNA sequencing. SM resistance was highly associated with rpsL mutations in M. tuberculosis. HRM technique represented an inexpensive, highly sensitive and high-throughput method to facilitate the screening of large numbers of clinical samples for epidemiological studies of drug-resistance of M. tuberculosis, especially in developing countries.