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Updated: Jun 18, 2026
10:17
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
The genetic signature of conditional expression
J David Van Dyken1, Michael J Wade
1Department of Biology, Indiana University, Bloomington, Indiana 47405, USA. jdvandyk@indiana.edu
Genetics
|December 8, 2009
Summary
Conditionally expressed genes weaken natural selection, allowing harmful mutations to accumulate and hindering beneficial ones. This impacts genetic variation and adaptation, especially in large populations.
Area of Science:
- Evolutionary biology
- Genetics
- Population genetics
Background:
- Conditionally expressed genes are present in all individuals but only active in a subset.
- This pattern affects how natural selection acts on genes.
Purpose of the Study:
- To investigate the evolutionary consequences of conditional gene expression.
- To quantify the impact on mutation accumulation and adaptation.
Main Methods:
- Developed analytical approximations for selection strength under conditional expression.
- Utilized computer simulations to validate approximations.
- Modeled effects on sequence polymorphism at mutation-selection-drift equilibrium.
Main Results:
- Conditional expression weakens natural selection, promoting deleterious mutation accumulation.
- Sequence variation (polymorphism and divergence) is inflated by conditional expression.
- Rarely expressed genes incur higher costs for phenotypic plasticity.
Conclusions:
- Conditional expression significantly alters evolutionary trajectories.
- Null hypotheses for genetic variation and divergence need adjustment based on gene expression frequency.
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