6 CASES OF 7P DELETION - CLINICAL, CYTOGENETIC, AND MOLECULAR STUDIES

To date, 32 cases of partial 7p monosomy have keen described, 14 of wh ich have been associated with craniosynostosis (CRS). There is conside rable variation in the size and location of the deleted segment. Howev er, CRS appears to be consistently associated with either a deletion o r partial deletion 7p21-->7p22 or more rarely a deletion of 7p13-->7p1 4. Analysis of a panel of six 7p deletion cases (three with CRS) was u ndertaken using informative DNA probes, in order to characterize and d efine the extent of the deletions at the molecular level. There were f ive de novo deletions and one resulting from the unbalanced product of a paternal balanced insertion. The putative proximal CRS locus at 7p1 3-->7p14 does not appear to be allelic with Greig cephalopolysyndactyl y syndrome. Three probe positions have been refined: pJ5.11 (D7S10) pr eviously mapped to 7p14-->pter does not appear to map proximal to p15; TM102L (D7S135) does not map distal to p22; CRI-P137 (D7S65) maps dis tal to 7p13. (C) 1994 Wiley-Liss, Inc.