[Cytogenetic study of the parents of 85 index cases with regular trisomy 21].
The parents of 85 Down syndrome cases with regular 21 trisomy were studied cytogenetically. The lymphocyte chromosomes were stained with G-banding technique and 100 metaphases were analyzed in the father, the mother and the index case. Among the mothers two cases of mosaic 46, XX/47, XX, +21 (2.35%) were found and among the fathers no mosaic cases were found. Reciprocal and robertsonian translocations were not observed. In one of the fathers a pericentric inversion of the Y chromosome (0.61%) was found. The results are compared with those of similar studies and discussed in relation to genetic counseling and to the possible existence of an "interchromosomal effect" in man.
Armendares
S
S
Instituto de Investigaciones Antropológicas, Universidad Nacional Autónoma de México.
Buentello
L
L
Salamanca
F
F
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D009030:Mosaicism; D009630:Nondisjunction, Genetic; D014178:Translocation, Genetic
Estudio citogenético en los progenitores de 85 casos índice con trisomía 21 regular.