Bogliolo A R, Lauria-Pires L, Gibson W C
Departamento de Patologia, Faculdade de Ciencias da Saude, Universidade de Brasilia, Brasil.
Acta Trop. 1996 Mar;61(1):31-40. doi: 10.1016/0001-706x(95)00138-5.
The ploidy of Trypanosoma cruzi is until now undetermined although analysis of isoenzymes, molecular karyotype and DNA content suggest diploidy in a very plastic genome. Also, there has been no convincing demonstration of genetic exchange and it has been proposed that reproduction is clonal. We have compared 18 T cruzi stocks and clones from the same area or host by means of isoenzyme analysis (12 loci) and restriction site polymorphisms in and around three glycolytic genes (glyceraldehyde-3-phosphate dehydrogenase, aldolase and glucosephosphate isomerase). The analysis demonstrated the presence of homozygotes and heterozygotes and is compatible with diploidy for these housekeeping genes. This strongly supports the hypothesis of genetic exchange in T cruzi and further elucidates the genetic diversity within natural T cruzi populations.
克氏锥虫的倍性至今尚未确定，尽管对同工酶、分子核型和DNA含量的分析表明，在一个可塑性很强的基因组中存在二倍体。此外，尚未有令人信服的基因交换证据，有人提出其繁殖方式为克隆繁殖。我们通过同工酶分析（12个位点）以及三个糖酵解基因（甘油醛-3-磷酸脱氢酶、醛缩酶和葡萄糖磷酸异构酶）内部及周围的限制性位点多态性，比较了来自同一地区或宿主的18个克氏锥虫株系和克隆。分析表明存在纯合子和杂合子，这与这些管家基因的二倍体情况相符。这有力地支持了克氏锥虫存在基因交换的假说，并进一步阐明了克氏锥虫自然种群内部的遗传多样性。
