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Published on: September 20, 2016
The evolution of genetic networks by non-adaptive processes
1Department of Biology, Indiana University, Bloomington, Indiana 47405, USA. milynch@indiana.edu
Nature Reviews. Genetics
|September 20, 2007
Summary
Genetic drift, mutation, and recombination can shape genetic networks without natural selection. This challenges the assumption that adaptive evolution is the sole driver of gene network origins.
Area of Science:
- Evolutionary biology
- Systems biology
- Genetics
Background:
- Natural selection is widely assumed to shape genetic networks.
- The adaptive origin of genetic network features lacks formal demonstration.
Purpose of the Study:
- To investigate the role of non-adaptive processes in shaping genetic networks.
- To question the sufficiency of natural selection for explaining gene-network topologies.
Main Methods:
- Analysis of qualitative features of known transcriptional networks.
- Consideration of non-adaptive evolutionary processes: genetic drift, mutation, and recombination.
Main Results:
- Many qualitative features of transcriptional networks can emerge through non-adaptive processes.
- Natural selection may not be necessary or sufficient for the origin of many gene-network aspects.
Conclusions:
- Non-adaptive evolutionary mechanisms play a significant role in genetic network evolution.
- Computational methods for studying network evolution should incorporate population-genetic details.
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