Scientific article

Two high throughput technologies to detect segmental aneuploidies identify new Williams-Beuren syndrome patients with atypical deletions

Published inJournal of medical genetics, vol. 43, no. 3, p. 266-273
Publication date2006

OBJECTIVE: To develop and compare two new technologies for diagnosing a contiguous gene syndrome, the Williams-Beuren syndrome (WBS). METHODS: The first proposed method, named paralogous sequence quantification (PSQ), is based on the use of paralogous sequences located on different chromosomes and quantification of specific mismatches present at these loci using pyrosequencing technology. The second exploits quantitative real time polymerase chain reaction (QPCR) to assess the relative quantity of an analysed locus. RESULTS: A correct and unambiguous diagnosis was obtained for 100% of the analysed samples with either technique (n = 165 and n = 155, respectively). These methods allowed the identification of two patients with atypical deletions in a cohort of 182 WBS patients. Both patients presented with mild facial anomalies, mild mental retardation with impaired visuospatial cognition, supravalvar aortic stenosis, and normal growth indices. These observations are consistent with the involvement of GTF2IRD1 or GTF2I in some of the WBS facial features. CONCLUSIONS: Both PSQ and QPCR are robust, easy to interpret, and simple to set up. They represent a competitive alternative for the diagnosis of segmental aneuploidies in clinical laboratories. They have advantages over fluorescence in situ hybridisation or microsatellites/SNP genotyping for detecting short segmental aneuploidies as the former is costly and labour intensive while the latter depends on the informativeness of the polymorphisms.

  • Aneuploidy
  • Diagnosis, Differential
  • Humans
  • In Situ Hybridization, Fluorescence
  • Polymerase Chain Reaction
  • Polymorphism, Genetic
  • Sequence Deletion
  • Williams Syndrome/classification/diagnosis/ genetics
Citation (ISO format)
HOWALD, C. et al. Two high throughput technologies to detect segmental aneuploidies identify new Williams-Beuren syndrome patients with atypical deletions. In: Journal of medical genetics, 2006, vol. 43, n° 3, p. 266–273. doi: 10.1136/jmg.2005.034009
Main files (1)
ISSN of the journal0022-2593

Technical informations

Creation07/12/2010 11:58:22 AM
First validation07/12/2010 11:58:22 AM
Update time03/14/2023 3:51:23 PM
Status update03/14/2023 3:51:23 PM
Last indexation02/12/2024 6:52:38 PM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack