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Published on: November 3, 2010
Sexually antagonistic genes: experimental evidence
1Biology Board of Studies, University of California, Santa Cruz 95064.
Science (New York, N.Y.)
|June 5, 1992
Summary
Sexually antagonistic mutations, beneficial in one sex but harmful in another, can interfere with adaptive evolution. This study shows such genes accumulate near new sex-determining genes, even with high harm-to-benefit ratios.
Area of Science:
- Evolutionary genetics
- Population genetics
- Sexual conflict
Background:
- Sexually antagonistic (SA) selection occurs when mutations have opposing fitness effects in males and females.
- The shared gene pool between sexes can lead to antagonistic pleiotropy, where a gene beneficial in one sex is detrimental in the other.
- Theory predicts SA mutations will accumulate in linkage disequilibrium with new sex-determining loci.
Purpose of the Study:
- To experimentally test the theory that sexually antagonistic mutations accumulate near new sex-determining genes.
- To investigate the evolutionary dynamics of genes under sexually antagonistic selection in a controlled system.
Main Methods:
- Utilized a *Drosophila melanogaster* model system.
- Employed genetic markers and artificial selection to create a pair of autosomal genes that segregated as a new sex-determining system.
- Conducted a 29-generation experimental evolution study.
Main Results:
- Provided experimental evidence supporting the theoretical prediction.
- Demonstrated the accumulation of sexually antagonistic genes in tight linkage with the induced sex-determining genes.
- Observed this accumulation even when the harm-to-benefit ratio of the mutations was high.
Conclusions:
- Sexually antagonistic genes may be common in natural populations.
- The evolution of new sex-determining genes can drive the accumulation of linked sexually antagonistic mutations.
- This process can significantly impact the adaptive evolution of both sexes.
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