title: Microsatellite analysis reveals genetic structure of Leishmania tropica.
abstract: The current rapid spread of leishmaniases caused by Leishmania tropica and the complexity of its clinical spectrum call for this parasite's epidemiological and evolutionary investigation. Evaluation of its population structure by isoenzyme electrophoresis and previous molecular biological analysis has proved difficult. In this study, we used 21 microsatellite loci to type 117 strains from different African and Asian locations. Eighty-one different genotypes were found. A genetic bottleneck supported by a gradient in the number of alleles and consistent with the geographical structure of the Middle East suggests an African origin of this species. A Bayesian approach identified 10 genetic clusters that correlated predominantly with geographical origin. The strains in the 'Asia' cluster form a very heterogeneous sub-population, with a varied but inter-related genotype that is geographically very widely dispersed and consistent with anthroponotic transmission of the parasite. The other nine clusters were more homogenous. The propagation of L. tropica appears to be predominantly clonal. In Africa and the Middle East, anthroponotic and zoonotic systems of distribution may contribute to the development of overlapping, genetically distinct populations of L. tropica.
authors.affiliation: Institute of Microbiology and Hygiene, Humboldt University, Charité Campus Mitte, Dorotheenstr. 96, D-10117 Berlin, Germany. jschwenk@vet.uga.edu
authors.forename: Jan M
authors.initials: JM
authors.lastname: Schwenkenbecher
authors.forename: Thierry
authors.initials: T
authors.lastname: Wirth
authors.forename: Lionel F
authors.initials: LF
authors.lastname: Schnur
authors.forename: Charles L
authors.initials: CL
authors.lastname: Jaffe
authors.forename: Henk
authors.initials: H
authors.lastname: Schallig
authors.forename: Amer
authors.initials: A
authors.lastname: Al-Jawabreh
authors.forename: Omar
authors.initials: O
authors.lastname: Hamarsheh
authors.forename: Kifaya
authors.initials: K
authors.lastname: Azmi
authors.forename: Francine
authors.initials: F
authors.lastname: Pratlong
authors.forename: Gabriele
authors.initials: G
authors.lastname: Schönian
mesh_terms: D000349:Africa; D000818:Animals; D001208:Asia; D017125:Genes, Protozoan; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D005843:Geography; D007895:Leishmania tropica / Q000235:genetics*; D018895:Microsatellite Repeats; D008957:Models, Genetic