title: Trisomy 21 with 47,+18 lymphocyte cell line: double mitotic nondisjunction.
abstract: A patient with Down's syndrome was found to have 47,XX,+18/47,XX,+21 mosaicism. Chromosome 18 trisomy was found only in 18% of lymphocytes and not in skin fibroblasts. A likely interpretation is double nondisjunction in a single lymphocyte precursor of a trisomy 21 embryo. A brief review of other cases of mitotic multiple nondisjunction and double aneuploid mosiacism is presented.
mesh_terms: D000328:Adult; D002902:Chromosomes, Human, 16-18; D004314:Down Syndrome / Q000235:genetics*; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics; D007621:Karyotyping; D009030:Mosaicism; D010641:Phenotype; D014314:Trisomy