IDENTIFICATION OF TRYPANOSOMA-EVANSI, TRYPANOSOMA-EQUIPERDUM AND TRYPANOSOMA-BRUCEI-BRUCEI USING REPETITIVE DNA PROBES

The phylogenetic relatedness of 15 stocks of Trypanosoma evansi, three stocks of Trypanosoma equiperdum and one stock of Trypanosoma brucei brucei was determined using Southern blot analysis of restriction enzyme digested DNA, probed with two repetitive DNA sequences from T. b. brucei. A dendrogram derived by cluster analysis of restriction fragment length polymorphism (RFLP) revealed three groups of related stocks. Group 1 included 14 stocks of T. evansi and one stock of T equiperdum. Group 2 included two stocks of T. equiperdum and one stock of T. evansi. Group 3 included the one stock of T brucei brucei. Group 2 is more closely related to Group 3 than Group 1, by analysis of the banding patterns. Further analysis of the T evansi in Group 1 revealed that the patterns of isolates from different provinces in China were identical, but differed from T. evansi isolated from Africa, South America and the Philippines. These results provide insight into the origins of T. evansi and suggest that RFLP may be a useful means of distinguishing closely related trypanosomes.