Usefulness of microsatellite typing in population genetic studies of Trypanosoma cruzi

Memórias do Instituto Oswaldo Cruz

Andrea M Macedo²  Juliana R Pimenta²  Renato S De Aguiar²  Anna Izabel R Melo²  Egler Chiari¹  Bianca Zingales¹  Sérgio Dj Pena²  Riva P Oliveira¹ 

[1] ,Universidade Federal de Minas Gerais Instituto de Ciências Biológicas Departamento de Bioquímica e Imunologia

关键词: Trypanosoma cruzi;    microsatellites;    genetic typing;    rDNA classification;    phylogenetic inference;   

DOI  :  10.1590/S0074-02762001000300023

来源: SciELO

【 摘 要 】

Through microsatellite analysis of 53 monoclonal populations of Trypanosoma cruzi, we found a remarkable degree of genetic polymorphism with no single multilocus genotype being observed more than once. The microsatellite profile proved to be stable during 70 generations of the CL Brener clone in culture. The microsatellite profiling presented also high diagnostic sensitivity since DNA amplifications could be achieved with less than 100 fg DNA, corresponding to half parasite total DNA content. Based on these technical attributes the microsatellite assay turns out to be an important tool for direct typing T. cruzi in biological samples. By using this approach we were able to type T. cruzi in feces of artificially infected bugs and in single cells sorted by FACS. The microsatellites have shown to be excellent markers for T. cruzi phylogenetic reconstruction. We used maximum parsimony based on the minimum number of mutational steps to build an unrooted Wagner network, which confirms previous conclusions based on the analysis of the D7 domain of the LSU rDNA gene that T. cruzi is composed by two major groups. We also obtained evidence that strains belonging to rRNA group 2 are subdivided into two genetically distant clusters, and that one of these clusters is more related to rRNA group 1/2. These results suggest different origins for these strains.

【 授权许可】

CC BY   
 All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License