Identification and diagnosis ofLeishmania mexicanacomplex isolates by polymerase chain reaction

Abstract

SUMMARYFollowing cloning ofLeishmania(L.)amazonensiskinetoplast DNA two recombinant clones were identified: one specific forL. (L.)amazonensisand the other specific forL. (L.)amazonensisand closely related isolates. DNA sequences from these clones were compared with those of other kinetoplastids and oligonucleotide primers were designed to be used in the polymerase chain reaction. A pair of these primers has been shown not only to be highly specific forL. mexicanacomplex isolates but can also be used to distinguish betweenL. (L.)mexicanaandL. (L.)amazonensisisolates. These primers have been tested with water-lysed cultures, crude DNA extracts from human patients, potential host reservoirs, sandfly vectors and with cell pellets after isoenzyme characterization. The results of these tests indicate that the primers can be used specifically in the presence of excess host DNA originating from the majority of South American countries.