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Detection of Copy Number Alterations Using Single Cell Sequencing
Published on: February 17, 2017
Somatic mosaicism for copy number variation in differentiated human tissues
Arkadiusz Piotrowski1, Carl E G Bruder, Robin Andersson
1Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama 35294-0024, USA.
Human Mutation
|June 24, 2008
Summary
Humans commonly exhibit somatic mosaicism due to copy number variations (CNVs) in a significant cell fraction. These genetic changes, affecting genes, may be misidentified as germline, impacting phenotype studies.
Area of Science:
- Genetics
- Genomics
- Human Biology
Background:
- Genetic variation includes single nucleotide polymorphisms (SNPs) and copy number variations (CNVs).
- Somatic mosaicism, genetic differences within an individual's cells, is not well understood for CNVs.
- Normal cells are generally assumed to be genetically identical.
Purpose of the Study:
- To investigate the occurrence and characteristics of somatic copy number variations (CNVs) in human tissues.
- To determine if CNVs arise in somatic cells and contribute to genetic mosaicism.
- To assess the implications of somatic CNVs for understanding human phenotypes and genetic variation.
Main Methods:
- Analysis of 34 tissue samples from three individuals.
- High-sensitivity detection of CNVs in a small fraction of cells (< or =10^-6).
- Characterization of CNV size, location, and potential gene impact.
Main Results:
- At least six CNVs were detected per subject, affecting single organs or multiple tissues.
- Observed CNVs ranged from 82 to 176 kb and frequently encompassed genes.
- Results indicate widespread somatic mosaicism for stochastic CNVs in humans.
Conclusions:
- Humans are commonly affected by somatic mosaicism for copy number variations (CNVs).
- Some CNVs previously identified as germline may actually be somatic events.
- Understanding somatic mosaicism is crucial for studying phenotypes and requires multi-tissue sampling in biobanks.
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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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