Gel electrophoresis of multiplex Genus (A) and RD9 (B) typing for isolates of Mycobacterium species. A: The multiplex Genus typing method used defines the genus Mycobacterium, MTBC, M. avium and M. intracellulare. Expected PCR Product for Mycobacterium genus, M. intracellulare, MTBC and M. avium were 1030 bp, 850 bp, 372 bp and 180 bp respectively. Lane 1, 100 bp DNA ladder; Lanes 2–9, selected isolates (Lanes 2–4, 6, 8, 9, isolates identified as of Mycobacterium genus; Lanes 2–4, 8, 9, isolates of MTBC; Lane 6, isolate of NTM); Lane 10–12, controls (Lane 10, M. tuberculosis H37Rv; Lane 11, M. bovis BCG; Lane 12, Negative control. B: RD9 typing showing expected PCR products for M. tuberculosis (RD9 intact, 396 bp) and for MTBC members other than M. tuberculosis (RD9 deleted, 575 bp). Lane 1 and 12, 100 bp DNA ladder; Lanes 2–8, selected isolates (Lanes 2 and 7, no PCR product (not of MTBC); Lane 3–6, 8, identified as M. tuberculosis; Lane 9–11, controls (M. tuberculosis H37Rv; Lane 10, negative control (H2O Qiagen); Lane 11, M. bovis AF2122/97.