We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Atypical deletions suggest five 22q11.2 critical regions related to the DiGeorge/velo-cardio-facial syndrome.
- Authors
Amati, Francesca; Conti, Emanuela; Novelli, Antonio; Bengala, Mario; Digilio, Maria Cristina; Marino, Bruno; Giannotti, Aldo; Gabrielli, Orazio; Novelli, Giuseppe; Dallapiccola, Bruno
- Abstract
Deletions of chromosome 22q11.2 have been associated with distinct phenotypes including DiGeorge syndrome (DGS) and velo-cardio-facial (VCFS) syndrome. These diseases result from a failure to form derivatives of the third and fourth branchial arches during development. DGS/VCFS deletions usually encompass about 3 Mb of genomic DNA in more than 90% of patients. However, deletion mapping studies have failed to demonstrate the existence of a single small region of overlap (SRO) and ruled out any obvious correlation between site or size of deletion and severity of clinical phenotype. We describe three patients carrying 'atypical' deletions presenting the DGS/VCFS phenotype. A comparative analysis of deletions in our patients and those previously published has suggested the existence of five distinct critical regions within the 22q11.2 locus. This observation argues that DGS/VCFS results from haploinsufficiency secondary to a complex and as yet unexplained molecular mechanism, probably involving chromatin effects in mediating gene expression throughout the entire region.
- Subjects
GENE expression; HUMAN chromosome abnormalities; HUMAN genetics
- Publication
European Journal of Human Genetics, 1999, Vol 7, Issue 8, p903
- ISSN
1018-4813
- Publication type
Article
- DOI
10.1038/sj.ejhg.5200399