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Updated: Jul 13, 2026
12:02
Molecular Evolution of the Tre Recombinase
Published on: May 29, 2008
The evolutionary fate and consequences of duplicate genes
1Department of Biology, University of Oregon, Eugene, OR 97403, USA. mlynch@oregon.uoregon.edu
Science (New York, N.Y.)
|November 10, 2000
Summary
Gene duplication is common, but most duplicates are quickly lost. Few evolve new functions, yet their silencing may drive species evolution.
Area of Science:
- Evolutionary biology
- Genomics
Background:
- Gene duplication is considered a key driver of evolutionary novelty.
- The rates of gene duplication and subsequent functional evolution remain poorly understood.
Purpose of the Study:
- To investigate the frequency of gene duplication events.
- To determine the evolutionary fate of gene duplicates in eukaryotes.
Main Methods:
- Analysis of genomic databases from multiple eukaryotic species.
- Estimation of gene duplication rates.
- Assessment of selection pressures on duplicate genes over time.
Main Results:
- Duplicate genes arise at a high rate (approx. 0.01 per gene per million years).
- Most duplicates undergo relaxed selection, with many becoming effectively neutral.
- The majority of gene duplicates are silenced within millions of years.
- Surviving duplicates are subject to strong purifying selection.
- New functional evolution in duplicates is rare.
Conclusions:
- While new functions from gene duplicates are infrequent, their stochastic silencing can contribute to speciation.
- Gene duplication provides raw material for evolution, but its impact is shaped by selection and silencing dynamics.
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