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Determining the Likelihood of Variant Pathogenicity Using Amino Acid-level Signal-to-Noise Analysis of Genetic Variation
Published on: January 16, 2019
Multivariate stabilizing selection and pleiotropy in the maintenance of quantitative genetic variation
Xu-Sheng Zhang1, William G Hill
1Institute of Cell, Animal and Population Biology, University of Edinburgh, West Mains Road, Edinburgh EH9 3JT, United Kingdom. xu-sheng.zhang@ed.ac.uk
Evolution; International Journal of Organic Evolution
|September 25, 2003
Summary
Quantitative genetic variation is maintained by mutation-selection balance. Apparent stabilizing selection is weaker than real selection, potentially relaxing mutation load in multivariate systems.
Area of Science:
- Quantitative genetics
- Evolutionary biology
- Population genetics
Background:
- Quantitative genetic variation is crucial for adaptation.
- Mutation-selection balance is a key mechanism for maintaining genetic variation.
- Multivariate selection complicates understanding of genetic variation maintenance.
Purpose of the Study:
- To investigate the maintenance of quantitative genetic variation under mutation-selection balance for multiple traits.
- To differentiate between intrinsic and apparent stabilizing selection strengths.
- To explore the impact of correlations in mutational effects and selection strengths.
Main Methods:
- Theoretical modeling of mutation-selection balance in a multivariate context.
- Analysis of stabilizing selection on a target trait and pleiotropic effects on other traits.
- Examination of the role of correlations among traits.
Main Results:
- Apparent stabilizing selection is weaker (stronger) than intrinsic stabilizing selection.
- Correlations among traits are generally unimportant unless very high.
- Multivariate stabilizing selection can maintain abundant genetic variance only under weak selection.
Conclusions:
- Distinguishing intrinsic and apparent selection can help relax mutation load.
- High observed polygenic variance and strong apparent selection suggest mutation-selection balance alone is insufficient.
- Apparent stabilizing selection likely involves mechanisms beyond simultaneous real stabilizing selection on many traits.
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