Polymorphisms at the topoisomerase II gene locus provide more evidence for the partition of Trypanosoma cruzi into two major groups.
We have dissected the topoisomerase II gene of members of the two recently characterized subgroups of Trypanosoma cruzi to obtain further evidence to support this dichotomy of isolates in this important parasite. Pulsed field gel electrophoresis showed a striking heterogeneity in the molecular karyotypes of the strains analyzed. Southern analysis of these chromosome gels also showed heterogeneity in the size and number of chromosomes containing the topoisomerase II gene. Analysis of DNA restriction fragment length polymorphisms of the topoisomerase II gene also showed two principal patterns consistent with the two previously characterized groups. Finally, the sequences of portions of the topoisomerase II genes from members of the T. cruzi groups showed two distinct patterns, again consistent with the previous grouping of this parasite. Thus, this work clearly supports previous observations suggesting an ancient divergence of known T. cruzi isolates into two main branches.
Dos Santos
W G
WG
Department of Microbiology and Immunology, Medical College of Virginia Campus, Virginia Commonwealth University, Richmond 23298-0678, USA.
Buck
G A
GA
D000818:Animals; D001483:Base Sequence; D017124:Conserved Sequence; D004250:DNA Topoisomerases, Type II / Q000235:genetics*; D016054:DNA, Protozoan; D017125:Genes, Protozoan; D018740:Genetic Heterogeneity; D007621:Karyotyping; D008969:Molecular Sequence Data; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D014349:Trypanosoma cruzi / Q000145:classification / Q000201:enzymology* / Q000235:genetics*
D016054:DNA, Protozoan; D004250:DNA Topoisomerases, Type II