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Evolution of primate gene expression: drift and corrective sweeps?
1Department of Statistics, University of Oxford, Oxford, United Kingdom.
Genetics
|September 16, 2008
Summary
Gene expression evolution in primates shows a consistent skew, favoring gene up-regulation. This study introduces mathematical models to confirm this pattern and suggests a "corrective sweep" mechanism driving primate evolution.
Area of Science:
- Evolutionary biology
- Genomics
- Bioinformatics
Background:
- Gene expression changes are crucial for species evolution.
- Previous studies suggested a skewed pattern in primate gene expression evolution, with more up-regulations than down-regulations.
- Lack of robust mathematical models hindered rigorous analysis of these evolutionary patterns.
Purpose of the Study:
- To develop and apply mathematical models for analyzing gene expression evolution.
- To rigorously test previous observations on skewed gene expression changes in primates.
- To investigate the evolutionary rates of brain-expressed genes.
Main Methods:
- Development of a mathematical model for skewed gene expression evolution within phylogenetic trees.
- Implementation of a separate model to handle biological or experimental outliers.
- Utilizing a Bayesian Markov chain Monte Carlo inference procedure for parameter estimation and confidence quantification.
Main Results:
- Strong evidence supporting a sustained positive skew in gene expression changes during primate evolution.
- Confirmation of previous findings regarding the skewed distribution of gene expression alterations.
- Identification of evolutionary parameters and phylogenetic inferences with quantified confidence.
Conclusions:
- The study confirms a significant skew towards gene up-regulation in primate evolution.
- A "corrective sweep" scenario is proposed as a potential explanation for the observed evolutionary pattern.
- The developed mathematical framework provides a robust tool for studying gene expression evolution.
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