Genetic clustering among Sudanese and geographically representative L. donovani strains. The multidimensional scaling plot shows a discriminant analysis of principal components based on 14 microsatellite loci. The optimal number of populations (10) is defined in the Bayesian information criterion (BIC) curve on the right hand side, by the `elbow’ of the BIC (y axis) vs population number (x axis) curve. Seven principal components were retained, explaining 80% of the total variation. Numeric labels correspond to population identities (see Additional file 1: Table S1 for further details). Yellow boxes indicate country of origin: SD - Sudan, IN-India, KE-Kenya, ET-Ethiopia, PT-Portugal, FR-France, ES-Spain. Red dashed boxes are used to table groups of clusters. Dog symbols alongside populations or dashed boxes indicate the presence of canine L. donovani strains. Green circles (1-3 in proportion to abundance) indicate clusters to which strains from Barbara El Fugara belong.