Trypanosoma cruzi: data supporting clonality in Mexican stocks.
To further study genetic heterogeneity of Mexican stocks of Trypanosoma cruzi, genomic Southern analyses from 54 Mexican isolates and 5 South American reference stocks were carried out. The membranes were hybridized with a homologous cDNA clone from the ribosomal protein S4 that identifies allelic bands from a single gene type locus. These allelic bands were sequentially numbered depending on their relative size. Mexican T. cruzi stocks were quite homogeneous: 31 cases (57%) showed a homozygous genotype 3/3, and 21 isolates (38%) exhibited the heterozygote genotype 2/3. Just 2 Mexican stocks (3%) showed a different genotype 2/5, but the potential parental homozygous 2/2 was never observed. Being that T. cruzi is a diploid organism, the apparent absence of the presumptive parental homozygous genotype 2/2 argues against sexual reproduction within the population, at least as a common event. Therefore, these data support a clonal population structure of T. cruzi in Mexico.
Hernández
R
R
Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, México City.
Herrera
J
J
Bosseno
M F
MF
Brenière
S F
SF
Espinoza
B
B
D000818:Animals; D015139:Blotting, Southern; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics*; D014644:Genetic Variation; D008800:Mexico; D012269:Ribosomal Proteins / Q000235:genetics; D014349:Trypanosoma cruzi / Q000737:chemistry / Q000145:classification / Q000235:genetics*
D016054:DNA, Protozoan; D012269:Ribosomal Proteins; C031798:ribosomal protein S4