Efficient discrimination by MIRU-VNTRs of Mycobacterium tuberculosis clinical isolates belonging to the predominant SIT11/EAI3-IND ancestral genotypic lineage in Kerala, India

The present study evaluated the ability of MIRU-VNTRs to discriminate Mycobacterium tuberculosis [MTB] clinical isolates belonging to the SIT11/EAI3-IND ancestral genotypic lineage, which is highly prevalent in Kerala, India. Starting from 168 MTB clinical isolates, spoligotyping [discriminatory index of 0.9113] differentiated the strains into 68 distinct patterns, the biggest cluster being SIT11/48 SIT11 [n = 48]. The present study shows that 12-loci MIRUs and 3 ETRs allowed an efficient discrimination of these isolates [discriminatory indexes of 0.7819 and 0.5523, respectively]