Differentiation of M. tuberculosis strains by using our PCR-based genotyping method (A) and by IS6110-RFLP fingerprinting (B). Lanes: 1 and 2, M. tuberculosis ITM3288; 3 and 4, M. tuberculosis ITM3255; 5 and 6, M. tuberculosis ITM3192; 7, M. tuberculosis ITM3153; 8, M. tuberculosis ITM4454; 9, M. tuberculosis ITM3132; 10, M. tuberculosis ITM4451; 11, M. tuberculosis ITM4424; 12, M. tuberculosis ITM4337; 13, M. tuberculosis ITM4339; 14, M. tuberculosis MZ1830; 15, M. tuberculosis MZ1799; 16, M. tuberculosis KP8689; 17, M. tuberculosis KP2398; 18, M. tuberculosis KP3189; 19, M. tuberculosis SL19; 20, M. tuberculosis SL11; N, negative control; M, 100-bp DNA Ladder Plus (MBI Fermentas).