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Updated: Jul 4, 2026
09:37
An Integrated Approach for Microprotein Identification and Sequence Analysis
Published on: July 12, 2022
Pervasive positive selection on duplicated and nonduplicated vertebrate protein coding genes
Romain A Studer1, Simon Penel, Laurent Duret
1Department of Ecology and Evolution, Biophore, Lausanne University, CH-1015 Lausanne, Switzerland;
Genome Research
|June 20, 2008
Summary
Positive selection is widespread across vertebrate evolution, affecting most genes studied. This pervasive evolutionary force impacts few sites per gene and is not linked to gene duplication events.
Area of Science:
- Evolutionary biology
- Genomics
- Molecular evolution
Background:
- Understanding the drivers of evolutionary innovation is crucial.
- Positive selection, a key evolutionary mechanism, drives adaptive changes in genes.
- Previous studies have suggested limited roles for positive selection or specific evolutionary events.
Purpose of the Study:
- To investigate the prevalence and patterns of positive selection across vertebrate evolution.
- To determine if whole genome duplication events influence the occurrence of positive selection.
- To identify potential functional categories enriched for positive selection.
Main Methods:
- Employed a stringent branch-site codon model to detect positive selection.
- Analyzed 884 genes across vertebrate evolution.
- Assessed the impact of whole genome duplication events on positive selection prevalence.
Main Results:
- Positive selection was detected in 77% of the 884 genes analyzed.
- Positive selection primarily affected a small proportion of sites (0.9%-4.7%) on specific branches.
- No specific functional categories were found to be overrepresented among genes under positive selection.
- Whole genome duplication events, including the fish-specific and early vertebrate duplications, did not affect the prevalence of positive selection.
Conclusions:
- Positive selection is a pervasive force throughout vertebrate evolution, not restricted to a few gene classes.
- The impact of positive selection is typically localized to a few sites within genes.
- Evolutionary events like gene duplication do not appear to be primary drivers for the prevalence of positive selection in vertebrates.
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