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Frequency and Distribution of Crossovers in Caenorhabditis elegans Meiosis by SNP Genotyping using Real-time PCR
Published on: July 11, 2025
Selection on recombination in clines.
D Charlesworth1, B Charlesworth
1Laboratory of Environmental Mutagenesis, National Institute of Environmental Health Sciences, P. O. Box 12233, Research Triangle Park, North Carolina 27709.
Genetics
|March 1, 1979
Summary
Computer simulations explored Slatkin's model for selection on recombination rates. Selection can favor increased recombination, but often favors decreased recombination, especially with weaker selection on linked loci.
Area of Science:
- Population genetics
- Evolutionary biology
- Computational biology
Background:
- Recombination rates are crucial for genetic diversity and evolution.
- Environmental changes can influence selection pressures on linked genes.
- Slatkin's (1975) model provides a framework for studying selection on recombination.
Purpose of the Study:
- To investigate the existence and direction of selection pressures on recombination rates.
- To examine how environmental changes affect selection on recombination in linear populations.
- To analyze the influence of linked loci on recombination rate evolution.
Main Methods:
- Computer simulations based on Slatkin's (1975) model.
- Analysis of allele frequency changes at a third locus controlling recombination.
- Modeling of both haploid and diploid selection scenarios.
Main Results:
- Selection for increased recombination can occur under specific parameter values.
- Changes in parameter values frequently shift selection towards decreased recombination.
- Selection for decreased recombination is often stronger than selection for increased recombination.
- Weaker selection on the primary loci tends to increase selection for decreased recombination.
Conclusions:
- Selection pressures on recombination rates are complex and context-dependent.
- Environmental variability can lead to fluctuating selection on recombination.
- The strength of selection on linked loci significantly impacts recombination rate evolution.
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