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An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
Widespread monoallelic expression on human autosomes
Alexander Gimelbrant1, John N Hutchinson, Benjamin R Thompson
1Center for Human Genetic Research and Department of Medicine, Massachusetts General Hospital, Harvard Medical School, Simches Research Building, 185 Cambridge Street, Boston, MA 02114, USA.
Science (New York, N.Y.)
|November 17, 2007
Summary
Random monoallelic gene expression, where only one of two parental gene copies is active, is more common than previously thought. This finding in human cells suggests a novel mechanism for generating cellular diversity.
Area of Science:
- Genetics and Genomics
- Molecular Biology
- Epigenetics
Background:
- Monoallelic gene expression, involving the random selection of either the maternal or paternal allele, is a known characteristic of X-inactivated genes and certain autosomal gene families.
- Understanding the prevalence and mechanisms of monoallelic expression is crucial for comprehending gene regulation and cellular heterogeneity.
Purpose of the Study:
- To conduct a genome-wide assessment of allele-specific transcription in human cells to identify genes exhibiting random monoallelic expression.
- To investigate the extent of random monoallelic expression across a large set of human genes and its implications for cellular diversity.
Main Methods:
- Utilized a genome-wide approach to analyze allele-specific transcription.
- Examined approximately 4000 human genes in clonal cell lines to identify patterns of monoallelic and biallelic expression.
Main Results:
- Identified over 300 human genes that are subject to random monoallelic expression.
- Observed that a majority of these monoallelic genes also exhibited biallelic expression in some clonal cell lines, indicating independent allelic choices.
- Demonstrated that random monoallelic expression can lead to variations in expressed protein sequences and gene expression levels among cells.
Conclusions:
- The widespread occurrence of random monoallelic expression suggests it is a significant biological mechanism.
- This phenomenon likely contributes to generating functional diversity within individual cells and their clonal descendants.
- Further research is warranted to elucidate the precise molecular mechanisms underlying this widespread random monoallelic expression.
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