title: Down's syndrome at young maternal age; cytogenetical and genealogical study of eighty-two families.
mesh_terms: D000293:Adolescent; D000328:Adult; D002869:Chromosome Aberrations; D002901:Chromosomes, Human, 13-15; D002904:Chromosomes, Human, 21-22 and Y; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007621:Karyotyping; D008297:Male; D008423:Maternal Age; D009030:Mosaicism; D012730:Sex Chromosomes