10P DUPLICATION CHARACTERIZED BY FLUORESCENCE IN-SITU HYBRIDIZATION

We describe a patient with severe failure to thrive, mild-moderate dev elopmental delay, cleft lip and palate, and other anomalies. Routine c ytogenetic analysis documented a de novo chromosome rearrangement invo lving chromosome 4, but the origin of the derived material was unknown . Using chromosome specific painting probes, the karyotype was defined as 46,XY,der(4) t(4;10) (q35;p11.23). Characterization of the dup(10p ) by fluorescence in situ hybridization (FISH) analysis provides anoth er example of the usefulness of this technology in identifying small d eletions, duplications, or supernumerary marker chromosomes. (C) 1994 Wiley-Liss, Inc.