FISH ANALYSIS IN PRADER-WILLI AND ANGELMAN SYNDROME PATIENTS

We report on a combined high resolution cytogenetic and fluorescent in situ hybridization study (FISH) on 15 Prader-Willi syndrome (PWS) and 14 Angelman syndrome (AS) patients. High resolution banding showed a microdeletion in the 15q11-q13 region in 7 out of 15 PWS patients, and FISH analysis of the D15S11 and SNRPN cosmids demonstrated absence of the critical region in three additional cases. Likewise 8 out of 14 A S patients were found to be deleted with FISH, using the GrABRB3 speci fic cosmid, whereas only 4 of them had a cytogenetically detectable de letion. (C) 1995 Wiley-Liss, Inc.