Résumé
Here we define a new approach for the detection and characterisation of
Leishmania complexes by polymerase chain reaction (PCR) and specific hybridisation. The first step consists of PCR amplification of kDNA minicircles using general kinetoplastid primers, which generate a polymorphic multi-banding pattern for all
Leishmania species and other Kinetoplastidae. The second step is the identification of the
Leishmania species complexes by hybridisation of the PCR products with specific kDNA probes. Polymorphic PCR-products from a genetically diverse set of
Leishmania species were analysed by electrophoresis and the banding patterns compared with multi-locus enzyme electrophoresis (MLEE) data. The banding patterns produced by
Leishmania species were very heterogeneous, making kDNA-PCR useful for determining closely related strains and for fingerprinting individual strains. The degree of kDNA-PCR and MLEE polymorphism was compared using UPGMA dendrograms. Three complex-specific probes were generated from major PCR bands of reference stocks belonging to the
Leishmania mexicana,
Leishmania donovani and
Leishmania braziliensis complexes, and hybridisation of these probes to membrane-bound PCR products could reliably identify the strain to a complex level. A combination of kDNA-PCR fingerprinting and hybridisation with kDNA probes was found to be useful for both sensitive detection and direct identification of
Leishmania species complexes.