TRISOMY-12 MOSAICISM IN A 7 YEAR-OLD GIRL WITH DYSMORPHIC FEATURES AND NORMAL MENTAL-DEVELOPMENT

We present the case of a mentally normal 7 year old girl with short st ature, scoliosis, atrial septal defect, and dysmorphic features includ ing linear pigmented streaks on the forearms and lower legs. Chromosom e analysis of cultured fibroblasts showed trisomy 12 in 9% and 13% of cells from two skin biopsies. Two trisomy 12 cells were found in lymph ocytes after analysis of 500 metaphases. Her clinical features are com pared with those of other liveborn cases of trisomy 12 mosaicism and t he problems of prenatal diagnosis of such an abnormality are discussed .