Related Experiment Video
Updated: Jun 15, 2026
09:16
Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants
Published on: February 21, 2015
Delineation of 15q13.3 microdeletions
A Masurel-Paulet1, J Andrieux, P Callier
1Centre de Génétique et Centre de Référence Anomalies du développement et syndromes malformatifs, Hôpital d'Enfants, CHU, Dijon.
Clinical Genetics
|March 19, 2010
Summary
The 15q13.3 microdeletion, identified via array-CGH in developmental delay patients, shows variable symptoms and incomplete penetrance. Males are more often affected, and a rare homozygous deletion causes severe neurodevelopmental issues.
Area of Science:
- Genetics
- Human Genetics
- Medical Genetics
Background:
- Array-comparative genomic hybridization (array-CGH) is crucial for identifying copy number variations (CNVs).
- The 15q13.3 microdeletion, a recognized genomic imbalance, is associated with developmental delay (DD) and related features.
- Previous studies have reported approximately 100 index cases, highlighting a broad phenotypic spectrum.
Purpose of the Study:
- To report a new cohort of patients with the 15q13.3 BP4-BP5 microdeletion.
- To confirm clinical expressivity and incomplete penetrance.
- To investigate the role of CHRNA7 and describe homozygous and smaller deletions.
Main Methods:
- Array-comparative genomic hybridization (array-CGH) screening of 4625 patients with DD.
- Analysis of 12 new index patients and 13 relatives with heterozygous BP4-BP5 microdeletion.
- Literature review and sequence analysis of the CHRNA7 gene.
Main Results:
- Confirmed clinical expressivity and incomplete penetrance in seven families.
- Males were found to be more frequently symptomatic.
- Reported the first case of a homozygous 15q13.3 microdeletion with severe epileptic encephalopathy, retinopathy, autistic features, and choreoathetosis.
- Identified three index patients with a smaller 500 kb microdeletion encompassing CHRNA7.
Conclusions:
- The 15q13.3 microdeletion presents a wide range of phenotypes and incomplete penetrance, with males being more susceptible.
- The CHRNA7 gene sequence analysis did not reveal recessive variants as a cause for phenotypic variability.
- The study expands the understanding of 15q13.3 microdeletion phenotypes, including homozygous and smaller deletion variants.
