Copy Number Variation in the Williams Syndrome Region: Detection of 7q11.23 Duplication by Microarray Allows Phenotypic Comparison

Abstract

Event Abstract Back to Event Copy Number Variation in the Williams Syndrome Region: Detection of 7q11.23 Duplication by Microarray Allows Phenotypic Comparison C. A. Morris1*, S. L. Velleman2, C. B. Mervis3, A. E. John3, A. Currier3, E. Peregrine3, C. Rios1, K. Kimberley1, H. Hobart1, G. Gowans3 and M. Gulbronson3 1 University of Nevada, School of Medicine, United States 2 University of Massachusetts, United States 3 University of Louisville, United States Williams syndrome (WS) is caused by a deletion of ~25 genes on chromosome 7q11.23 mediated by nonallelic homologous recombination. The advent of chromosome microarray technology has resulted in detection of the reciprocal duplication of the region. The purpose of this report is to define the WS region duplication phenotype, and to compare it to WS in order to identify traits that are sensitive to copy number/gene dosage. Method: Physical examinations and cognitive and language assessments were performed on 8 children and one adult (mother of 2 of the children) with duplications of the classic WS region (dup7q11.23), and on 2 children with longer duplications including HSP27 (deletion of which is associated with more severe intellectual disability in individuals with WS with long deletions). Phenotypic features were compared to individuals with classic WS. Results: Dysmorphic features included prominent forehead (65%), high broad nose (70%), long columnella (41% of total, but 90% of those over age 8), short philtrum (54%), and facial asymmetry (95%). Birth defects were rare, including one person each with ASD/VSD, microcephaly, hydrocephaly, and severe micrognathia. About 50% had ADHD, and 82% had anxiety (social and separation anxiety). Interestingly, all individuals with a duplication had language delay and current or former difficulty with motor speech. Discussion: The facial phenotype of duplication of the WS region is subtle, but recognizable. GTF2IRD1 has been implicated in the facial asymmetry in WS, and may be copy number sensitive, since it is a trait shared by the dup7 group. Both groups share anxiety as a behavioral problem, but those with WS typically have specific phobia (loud noises), while those with dup7 have separation and social anxiety. These findings suggest that one or more genes in the Williams syndrome region are dosage sensitive, including genes that contribute to facial and language development. Conference: 12th International Professional Conference on Williams Syndrome, Garden Grove,CA, United States, 13 Jul - 14 Jul, 2008. Presentation Type: Oral Presentation Topic: SESSION 4: Phenotype of the 7Q11.23 Duplication Citation: Morris CA, Velleman SL, Mervis CB, John AE, Currier A, Peregrine E, Rios C, Kimberley K, Hobart H, Gowans G and Gulbronson M (2009). Copy Number Variation in the Williams Syndrome Region: Detection of 7q11.23 Duplication by Microarray Allows Phenotypic Comparison. Conference Abstract: 12th International Professional Conference on Williams Syndrome. doi: 10.3389/conf.neuro.09.2009.07.012 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 29 Apr 2009; Published Online: 29 Apr 2009. * Correspondence: C. A Morris, University of Nevada, School of Medicine, Las Vegas, United States, cmorris@medicine.nevada.edu Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers C. A Morris S. L Velleman C. B Mervis A. E John A. Currier E. Peregrine C. Rios K. Kimberley H. Hobart G. Gowans M. Gulbronson Google C. A Morris S. L Velleman C. B Mervis A. E John A. Currier E. Peregrine C. Rios K. Kimberley H. Hobart G. Gowans M. Gulbronson Google Scholar C. A Morris S. L Velleman C. B Mervis A. E John A. Currier E. Peregrine C. Rios K. Kimberley H. Hobart G. Gowans M. Gulbronson PubMed C. A Morris S. L Velleman C. B Mervis A. E John A. Currier E. Peregrine C. Rios K. Kimberley H. Hobart G. Gowans M. Gulbronson Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.