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Updated: Jun 23, 2026
09:16
Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants
Published on: February 21, 2015
Comparative genomic hybridization: DNA labeling, hybridization and detection
Richard Redon1, Tomas Fitzgerald, Nigel P Carter
1Wellcome Trust, Sanger Institute, Cambridge, UK.
Methods in Molecular Biology (Clifton, N.J.)
|April 22, 2009
Summary
Array comparative genomic hybridization (Array-CGH) compares test genomes to reference genomes using microarrays. This method analyzes DNA copy number variations for genomic research and diagnostics.
Area of Science:
- Genomics
- Molecular Biology
- Biotechnology
Background:
- Array comparative genomic hybridization (Array-CGH) is a molecular-cytogenetic technique.
- It is used to detect chromosomal copy number variations (CNVs).
Purpose of the Study:
- To describe the protocols for Array-CGH using microarrays.
- To explain the process from DNA labeling to data interpretation.
Main Methods:
- Comparing test and reference genomes using fluorescently labeled DNA probes on microarrays.
- Co-hybridization with Cot-1 DNA to suppress repetitive sequences.
- Image acquisition via laser scanner and data analysis using specialized software.
Main Results:
- Extraction of fluorescent intensities and calculation of normalized intensity ratios.
- Enables detection of genomic imbalances.
Conclusions:
- The described protocols are applicable to large-insert clone microarrays.
- Adaptations for shorter DNA sequences on microarrays are also discussed.
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