title: Trisomy 9p and unusual translocation mongolism in siblings due to different 3:1 segregations of maternal translocation rcp(9;21)(p11;q11).
abstract: Two sisters are described, each with a specific retardation syndrome due to a balanced reciprocal translocation 9p;21q in the mother. As a result of different 3:1 segregations, one of them has a trisomy 9p with all typical features; the other one reveals a typical Down's syndrome having an unusual translocation karyotype.
mesh_terms: D000293:Adolescent; D000328:Adult; D001399:Azure Stains; D002675:Child, Preschool; D002875:Chromosomes / Q000648:ultrastructure; D002904:Chromosomes, Human, 21-22 and Y; D002906:Chromosomes, Human, 6-12 and X; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D006801:Humans; D007621:Karyotyping; D010375:Pedigree; D011796:Quinacrine; D014178:Translocation, Genetic; D014314:Trisomy
chemical_list: D001399:Azure Stains; D011796:Quinacrine