Multilocus sequence analysis provides new insight into population structure and genetic diversity of Leishmania tropica in Morocco.

Cutaneous leishmaniasis (CL) is one of the most neglected tropical diseases, caused by different Leishmania species. Despite its high incidence in Morocco, CL due to Leishmania tropica is poorly understood in terms of its epidemiological status and population structure. In this study, we used multilocus sequence typing (MLST) in order to explore the genetic heterogeneity of L. tropica strains. Samples (N = 48) were collected from CL patients in two localities in Morocco (Foum Jamaa in the Azilal province and Imintanoute in Chichaoua province). PCR-sequencing of 18 strains was carried out for six housekeeping genes (cytb, me, fh, g6pd, pgd and gpi), Genetic diversity indices showed a high population genetic differentiation between and among populations. There was no shared haplotypes between the two localities studied. Our results reveal a considerable degree of differentiation through the relatively high FST value (> 0.4) and remarkable intraspecific polymorphism (S = 29). Imintanoute strains have more polymorphisms (S = 22) than the Foum Jamaa strains despite their small sample size. These results provide crucial background information of epidemiology in Imintanoute which raises questions about animal involvement in L. tropica transmission cycle.