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Updated: May 23, 2026
09:16
Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants
Published on: February 21, 2015
Differences in Copy Number Variation between Discordant Monozygotic Twins as a Model for Exploring Chromosomal
J Breckpot1, B Thienpont, M Gewillig
1Center for Human Genetics, University Hospitals Leuven, Leuven, Belgium.
Molecular Syndromology
|April 19, 2012
Summary
Somatic copy number variations (CNVs) may play a role in congenital heart defects (CHDs). This study found CNV differences in one pair of monozygotic twins discordant for CHDs, suggesting postzygotic events contribute to heart development.
Area of Science:
- Genetics
- Developmental Biology
- Cardiology
Background:
- Studies on somatic copy number variation (CNV) in congenital heart defects (CHDs) are limited due to the difficulty of obtaining cardiac tissue.
- Monozygotic (MZ) twins discordant for CHDs offer a model to study chromosomal mosaicism in heart development.
Purpose of the Study:
- To investigate the occurrence of copy number differences in MZ twins discordant for CHDs.
- To explore the potential role of somatic CNVs in the etiology of CHDs.
Main Methods:
- Array comparative genomic hybridization (aCGH) was used.
- DNA from 6 discordant MZ twin pairs and controls was analyzed.
- Each twin's DNA was hybridized against its co-twin and a normal control.
Main Results:
- Three copy number differences were detected in one out of six MZ twin pairs.
- This confirms the occurrence of somatic CNV events in MZ twins.
- The findings suggest postzygotic genetic events can influence heart development.
Conclusions:
- Somatic CNV events occur in MZ twins and may contribute to CHD development.
- Further research using copy number and (epi)genome sequencing in discordant MZ twins is needed.
- Understanding the interplay of genetic, environmental, and stochastic factors is crucial for human heart development.
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Sequencing of the human genome has opened up several best-kept secrets of the genome. Scientists have identified thousands of genome variations that exist within a population. These variations can be a single nucleotide or a larger chromosomal variation.
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
Copy number variations or CNVs are the structural variations that cover more than 1kb of DNA sequence. The single nucleotide polymorphism (SNP), on the other hand, is a single nucleotide change or a point mutation that is found in more than 1%...
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