Detection of Mycobacterium leprae by three-primer PCR

Recently, polymerase chain reaction has been introduced for the species-specific assessment of Mycobacterium leprae (1). To avoid Southern blotting techniques using radioactively labelled oligonucleotide probes, the aim of this study was to establish a three primer-based single-step PCR technique. Using primers designed for this purpose we amplified a part of the gene encoding for the 16S ribosomal RNA of slowly growing mycobacteria. Due to the species-specific antisense primer a second, smaller fragment specific for M. leprae was amplified. Our results show that the employment of a second antisense primer in the PCR may be a substitution for Southern blot hybridization.