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Updated: Sep 20, 2025
10:17
An Allele-specific Gene Expression Assay to Test the Functional Basis of Genetic Associations
Published on: November 3, 2010
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The evolution of sex-specific gene expression in polygenic traits
1Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland.
Journal of Evolutionary Biology
|May 28, 2025
Summary
Sexual dimorphism evolves more readily through sex-specific gene amplification than sex-specific dominance. The genetic architecture underlying this dimorphism depends on the trait's genetic basis and optimal values for each sex.
Area of Science:
- Evolutionary biology
- Genetics
Background:
- Sexual selection often favors different phenotypes in males and females, driving the evolution of sex-specific genetic architectures.
- Previous single-locus models explored how gene expression modifiers and allelic dominance contribute to sexual dimorphism.
Purpose of the Study:
- To investigate the evolution of gene expression in polygenic traits under sex-specific selection.
- To compare the roles of sex-specific gene amplification versus sex-specific dominance in evolving sexual dimorphism.
Main Methods:
- Theoretical modeling of polygenic traits experiencing sex-specific selection.
- Analysis of how gene expression levels and dominance evolve across multiple loci.
Main Results:
- Sex-specific gene amplification (differences in absolute gene expression) is a more common driver of sexual dimorphism than sex-specific dominance.
- The evolution of sex-specific amplification is sensitive to the genetic redundancy of the trait and the distance between optimal male and female trait values.
Conclusions:
- The genetic architecture underlying sexual dimorphism is highly dependent on the trait's genetic basis.
- Current metrics of sexual antagonism may need re-evaluation due to the context-dependent nature of evolving genetic architectures.
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