Deletion (9) (p13.1 p21.1)

We report on a 22-month-old girl with minor facial anomalies, global develo pmental delay, growth retardation, seizures, and leukoencephalopathy, Initi al clinical assessment suggested the diagnosis of Williams syndrome, Result s of fluorescence in situ hybridization testing for elastin were normal. Ho wever, chromosome analysis showed a 46,XX,del(9) (p13.1p21.1) karyotype in pe ripheral lymphocytes. Parental chromosomes were normal, indicating a de novo de letion, This patient's manifestations are compared with those of tw o other cases with overlapping deletions of the proximal short arm of chrom osome 9, (C) 2000 Wiley-Liss, Inc.