Genetic diversity of Leishmania from Sudan and possible correlation to clinical signs: preliminary results

Leishmania species can cause diseases with a wide spectrum of clinical manifestations. Different types of diseases are caused by the same species group, whereas different species may cause the same type of disease. In this study we report the preliminary results of a multilocus molecular and phylogenetic analysis of Leishmania isolated from Sudanese patients. Samples were obtained from the eastern part of the country where the disease is endemic and from the Institute of Endemic Diseases, University of Khartoum. PCR and direct sequencing were used to analyse the polymorphisms in gp63 and minicircle kDNA genes of Leishmania strains from patients showing different clinical manifestations. The interspecific difference in the gp63 sequences ranged from 1.8% to 2.7%. A higher interspecific difference (0.8%-7.7%) was recorded for the kDNA sequences. The intraspecific nucleotidic variation ranged from 0.0% to 0.8% for both genes. Phylogenetic analysis of the Leishmania species sequenced in this study and of those available in GenBank™ were concordant in clustering Leishmania in two major clades, corresponding to L.donovani complex and L.major. Patients with visceral leishmaniasis, mucocutaneous or Post Kala-azar Dermal Leishmaniasis were infected by members of L.donovani complex. Patients with cutaneous lesions were infected by L.major with the exception of two patients infected by L.donovani.