PCR-ribotyping of pathogenic mycobacteria by an amplified ribosomal DNA fingerprinting assay

Alarming increase in the tuberculosis cases globally has led to increase in the interest for development of newer molecular techniques for identification and for strain variation of pathogenic mycobacteria. PCR-ribotyping has emerged as an important and powerful approach for characterization of various organisms. Based on extensive experiments, PCR assay targeting 1.8 kb fragment of spacer and flanking regions has been developed at CJIL, Agra. In this study 55 isolates of M. tuberculosis and other mycobacteria were analyzed to find out the usefulness of this method. DNAs from these isolates were purified by physio-chemical method. 1.8 Kb fragment was amplified and amplicons were digested with various restriction enzymes and electrophoresed to elicit variation. The technique has been observed to be useful for the characterization of isolates of pathogenic mycobacteria at species level.