title: Trisomy 18/trisomy 13 mosaicism in an adult with profound mental retardation and multiple malformations.
abstract: We report on an adult woman with profound mental retardation and multiple anomalies who consists of 3 cell lines: one with trisomy 18, one with trisomy 13, and a normal cell line. Her phenotype includes manifestations of both trisomy syndromes. The origin of these cell lines could have been a doubly aneuploid (48,XX + 13, + 18) or singly aneuploid (47,XX + 18 or 47,XX + 13) zygote with subsequent mitotic nondisjunctions, or a normal zygote with multiple mitotic nondisjunctions. There have been four previous reports of mosaicism involving both trisomy D and trisomy E; all died in the first six months of life. Two of these cases had a doubly aneuploid (48,XX, + D + E) cell line. Our patient illustrates the need for study of several tissues in patients with complex aneuploidy syndromes or atypical manifestations of a given syndrome (such as prolonged survival), as well as the need for caution in counseling families about prognosis for survival in autosomal trisomies which usually are lethal.
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics*; D000328:Adult; D002901:Chromosomes, Human, 13-15; D002902:Chromosomes, Human, 16-18; D005145:Face / Q000002:abnormalities; D005260:Female; D006392:Hemangioma, Cavernous / Q000235:genetics; D006801:Humans; D008607:Intellectual Disability / Q000235:genetics*; D009030:Mosaicism; D014314:Trisomy