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Epistasis for quantitative traits in Drosophila.
1Department of Biological Sciences, North Carolina State University, Campus Box 7614, Raleigh, NC, 27695-7614, USA, trudy_mackay@ncsu.edu.
Methods in Molecular Biology (Clifton, N.J.)
|November 19, 2014
Summary
Gene-gene interactions (epistasis) drive quantitative traits in Drosophila, challenging simple additive models. Additivity emerges from complex genetic networks, influencing evolution and hidden genetic variation.
Area of Science:
- Genetics
- Evolutionary Biology
- Quantitative Genetics
Background:
- The role of gene-gene interactions (epistasis) in quantitative trait variation is debated.
- Epistasis is biologically plausible due to nonlinear molecular interactions.
- Detecting epistasis in outbreeding populations is challenging, as absence of evidence is not evidence of absence.
Purpose of the Study:
- To review evidence for epistasis in Drosophila using focused genetic approaches.
- To explore the implications of epistasis for genetic architecture and evolutionary processes.
Main Methods:
- Review of studies employing de novo mutations, inbred lines, artificial selection, and chromosome substitution lines in Drosophila.
- Mapping of quantitative trait loci (QTL) using linkage and association analyses.
- Evaluation of induced mutations across diverse wild-derived backgrounds.
Main Results:
- Evidence suggests additivity is an emergent property of pervasive epistatic gene action in Drosophila.
- Studies reveal interconnected genetic networks enriched for specific biological pathways.
- Epistasis impacts the predictive power of additive models and contributes to genetic canalization.
Conclusions:
- Epistasis is a fundamental component of quantitative trait architecture in Drosophila.
- Understanding epistasis is crucial for inferring genetic networks and predicting evolutionary trajectories.
- Epistasis underlies hidden genetic variation and facilitates rapid evolution, including speciation.
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