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Updated: Jul 8, 2026
09:16
Array Comparative Genomic Hybridization (Array CGH) for Detection of Genomic Copy Number Variants
Published on: February 21, 2015
Segmental copy-number variation observed in Japanese by array-CGH
N Takahashi1, N Tsuyama, K Sasaki
1Department of Genetics, Radiation Effects Research Foundation, 5-2 Hijiyama Park, Minami-ku, Hiroshima, Japan. takahash@rerf.or.jp
Annals of Human Genetics
|January 22, 2008
Summary
This study identified rare and polymorphic copy-number variations (CNVs) in Japanese individuals. Rare CNVs, often novel and not overlapping segmental duplications, suggest population-specific genetic differences.
Area of Science:
- Human Genetics
- Genomics
- Molecular Biology
Background:
- Segmental copy-number variations (CNVs) are a source of human genetic diversity.
- Understanding the landscape of CNVs is crucial for human population genetics.
Purpose of the Study:
- To characterize rare and polymorphic CNVs in a Japanese population.
- To investigate the genomic features and potential origins of different CNV types.
Main Methods:
- Comparative genomic hybridization (array-CGH) using a microarray of 2,238 Bac-clones.
- Quantitative polymerase chain reactions (qPCR) for rare CNV validation.
Main Results:
- Identified 251 CNVs across 30 genomic regions in 80 individuals.
- Characterized 14 rare CNVs and 16 polymorphic CNV regions.
- Rare CNVs predominantly occurred outside segmental duplication regions, while polymorphic CNVs were often within them.
- Over 90% of polymorphic CNVs were previously identified; over 50% of rare CNVs were novel.
Conclusions:
- Rare and polymorphic CNVs likely arise from distinct genetic mechanisms.
- Novel rare CNVs suggest significant inter-population variation in CNV profiles, similar to SNPs and indels.
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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%...
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