title: Probing the genetic population structure of Trypanosoma cruzi with polymorphic microsatellites.
abstract: We describe here the identification of eight polymorphic microsatellite loci with (CA)n repeats in the Trypanosoma cruzi genome based on the affinity capture of fragments using biotinylated (CA)12 attached to streptavidin-coated magnetic beads. The presence of two peaks in PCR amplification products from individual clones confirmed that T. cruzi is diploid. Hardy-Weinberg and linkage disequilibrium analyses suggested that sexual reproduction is rare or absent and that the population structure is clonal. Several strains, especially those isolated from nonhuman sources, showed more than two alleles in many loci demonstrating that they were multiclonal. The phylogenetic analysis of T. cruzi based on microsatellites revealed a great genetic distance among strains, although the strain dispersion profile in the Wagner network was in general agreement with the species dimorphism found by PCR amplification of the divergent region of the rRNA 24Salpha gene.
authors.affiliation: Departamento de Bioquímica e Imunologia, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, 31270-901 Brazil.
authors.forename: R P
authors.initials: RP
authors.lastname: Oliveira
authors.forename: N E
authors.initials: NE
authors.lastname: Broude
authors.forename: A M
authors.initials: AM
authors.lastname: Macedo
authors.forename: C R
authors.initials: CR
authors.lastname: Cantor
authors.forename: C L
authors.initials: CL
authors.lastname: Smith
authors.forename: S D
authors.initials: SD
authors.lastname: Pena
mesh_terms: D000818:Animals; D004276:DNA, Satellite / Q000235:genetics*; D005828:Genetics, Population; D018503:Genome, Protozoan; D011110:Polymorphism, Genetic; D014349:Trypanosoma cruzi / Q000235:genetics*
chemical_list: D004276:DNA, Satellite