title: Secondary nondisjunction causing regular trisomy 21 in the offspring of a mosaic trisomy 21 mother.
mesh_terms: D000328:Adult; D002904:Chromosomes, Human, 21-22 and Y; D003582:Cytogenetics; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007621:Karyotyping; D009030:Mosaicism; D014314:Trisomy