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Updated: Jun 6, 2026
09:45
Detection of Copy Number Alterations Using Single Cell Sequencing
Published on: February 17, 2017
Screening for common copy-number variants in cancer genes
Jess Tyson1, Tamsin M O Majerus, Susan Walker
1Institute of Genetics, School of Biology, University of Nottingham, Queen's Medical Centre, Nottingham NG7 2UH, United Kingdom.
Cancer Genetics and Cytogenetics
|December 16, 2010
Summary
This study investigated copy number variants (CNVs) in colorectal cancer (CRC) predisposition genes. Researchers found a very low incidence of CNVs, suggesting they play a minimal role in hereditary CRC risk.
Area of Science:
- Genetics
- Oncology
- Molecular Biology
Background:
- Most colorectal cancer (CRC) cases without a family history are thought to involve a heritable predisposition from multiple genetic loci.
- While single nucleotide variants are studied, the role of low-penetrance copy number variants (CNVs) in CRC risk remains largely unexplored.
Purpose of the Study:
- To screen for CNVs in key colorectal cancer predisposition genes using a high-resolution assay.
- To assess the frequency and potential contribution of CNVs to hereditary colorectal cancer risk.
Main Methods:
- Utilized multiplex amplifiable probe hybridization (MAPH) in a fourfold multiplex (QuadMAPH) format.
- Screened 1.56 Mb of genomic DNA at high resolution (one probe per 2 kb) for CNVs.
- Focused on intronic and flanking regions of nine cancer-associated genes: APC, AXIN1, BRCA1, BRCA2, CTNNB1, HRAS, MLH1, MSH2, and TP53.
Main Results:
- Detected two deletion events: one upstream of MLH1 in a control and one in APC in a CRC patient.
- These identified deletions did not appear to be common copy number polymorphisms in the population.
- Demonstrated a very low incidence of deletion and duplication variants within the targeted regions of the nine genes in both CRC patients and controls.
Conclusions:
- The high-resolution QuadMAPH assay is capable of accurately detecting CNVs.
- CNVs within the intronic and flanking regions of the studied genes occur at a very low frequency.
- CNVs likely play a minimal role in the heritable predisposition to colorectal cancer for most sporadic cases.
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