IDENTIFICATION AND DETERMINATION OF THE RELATIONSHIPS OF SPECIES AND STRAINS WITHIN THE GENUS LEISHMANIA USING SINGLE PRIMERS IN THE POLYMERASE CHAIN-REACTION

DNA polymorphisms were assessed in different species and strains withi n the genus Leishmania by amplifying genomic DNA with single non-speci fic primers. This polymerase chain reaction (PCR) method employed non- random primers which anneal to mini- and microsatellite DNA sequences like the M13 core sequence and the simple repeat sequences (GTG)(5) an d (GACA)(4), and the T3B primer derived from an intergenic spacer for tRNA genes. Distinctive and reproducible sets of amplified DNA fragmen ts were obtained for all Leishmania isolates tested. The number and si ze of amplification products were found to be characteristic for a giv en taxon. Highly similar PCR profiles were observed when genomic DNA o f representatives of the L. donovani, L. mexicana or L. braziliensis c omplexes was amplified. By comparing PCR patterns of unidentified Leis hmania isolates with those obtained from reference strains it was poss ible to identify these isolates at the species level. The information of the amplification patterns was used for the construction of phyloge netic trees to measure the genetic relatedness within the genus Leishm ania.