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Long-term selection experiments: epistasis and the response to selection
1Department of Biology, University of Vermont, Marsh Life Science Building, 109 Carrigan Drive, Burlington, VT, 05405-0086, USA, charles.goodnight@uvm.edu.
Methods in Molecular Biology (Clifton, N.J.)
|November 19, 2014
Summary
Gene interaction, specifically epistasis, can explain extended responses and intermediate plateaus in long-term selection experiments, suggesting a richer source of genetic variation than previously assumed.
Area of Science:
- Evolutionary genetics
- Quantitative genetics
Background:
- Long-term selection experiments often show no limits due to genetic variation loss.
- Selection plateaus, where response halts for generations, are common in these experiments.
Purpose of the Study:
- To investigate the role of gene interaction (epistasis) in generating patterns observed in long-term selection experiments.
- To explore how epistasis influences genetic variation and response to selection over time.
Main Methods:
- Utilized previously published theoretical results.
- Employed a simple deterministic model to simulate selection experiments.
Main Results:
- Epistasis can provide a continuous source of genetic variation for selection.
- This variation can lead to extended responses to selection beyond initial expectations.
Conclusions:
- Gene interaction is a significant factor in maintaining genetic variation during long-term selection.
- Epistasis can explain the occurrence of intermediate selection plateaus observed in experiments.
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