RESUMEN
The present study applies multilocus microsatellite typing (MLMT) for studying the polymorphism among 55 strains of Leishmania infantum from Algeria. These strains from different Algerian foci representing different zymodemes, hosts and clinical forms were analysed using 14 microsatellite markers. All 55 strains had individual MLMT profiles and no relationship was observed between them and different host or geographical origins. Three populations of Algerian L. infantum were identified by a Bayesian clustering approach implemented in STRUCTURE software and supported by genetic distance analysis. Two populations, A and B, consisted mainly of strains belonging to zymodeme MON-1, and the third population, C, mainly of MON-24 strains isolated from cutaneous leishmaniasis cases. Interestingly, a small group of strains appeared as a mixture of different populations and might be putative hybrids. Genetic migration was noticed among the two MON-1 populations, A and B, as well as between populations A and C. Due to its high discriminatory power MLMT could be also successfully applied for differentiating relapses or re-infection for patients suffering from multiple episodes of visceral leishmaniasis.
Asunto(s)
Enfermedades de los Perros/epidemiología , Leishmania infantum/clasificación , Leishmania infantum/genética , Leishmaniasis Cutánea/epidemiología , Leishmaniasis Visceral/epidemiología , Repeticiones de Microsatélite/genética , Polimorfismo Genético , Argelia/epidemiología , Animales , Teorema de Bayes , ADN Protozoario/análisis , ADN Protozoario/aislamiento & purificación , Enfermedades de los Perros/parasitología , Perros , Genética de Población , Genotipo , Humanos , Leishmania infantum/aislamiento & purificación , Leishmaniasis Cutánea/parasitología , Leishmaniasis Visceral/parasitología , Epidemiología Molecular , Análisis de Secuencia de ADNRESUMEN
In recent years, new methods have been developed for the molecular typing of Leishmania that need to be extensively validated by studies of clinical isolates in a well defined epidemiological context. The present study is a contribution to this effort. Using PCR-RFLP of gp63 and cpb genes, we analysed 59 isolates of L. (L.) infantum obtained from different regions of Algeria and originating from different clinical forms, hosts and zymodemes. PCR-RFLP identified 15 different genotypes among the four zymodemes analysed, thereby demonstrating a higher discriminatory power than multilocus enzyme electrophoresis. We did not see any significant relationships between PCR-RFLP patterns and host origin. However, cpb polymorphism showed two interesting trends: a possible relationship with the cutaneous origin of the isolates and an association with a West-East cline. We verified the proof of evidence of the direct applicability of gp63 and cpb PCR-RFLP in blood samples from dogs. Further work is needed to compare the sensitivity of pattern detection with cpb and gp63 PCR-RFLP but our results pave the way to future multilocus PCR-RFLP studies of L. (L.) infantum populations.