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Updated: Jul 17, 2026
14:23
Recombineering Homologous Recombination Constructs in Drosophila
Published on: July 13, 2013
Selection for recombination in partially self-fertilizing populations.
D Charlesworth1, B Charlesworth, C Strobeck
1National Institute of EnvironmentalHealth Sciences, P. O. Box 12233.
Genetics
|September 1, 1979
Summary
Certain fitness interactions in partially selfing populations can drive selection for higher recombination rates. Population mean fitness changes may not always predict this selection direction.
Area of Science:
- Population Genetics
- Evolutionary Biology
- Quantitative Genetics
Background:
- Partial self-fertilization introduces complexities in genetic models.
- The relationship between fitness interactions and recombination rates is a key area in evolutionary genetics.
- Holden's (1979) work suggested a link between specific fitness interactions and selection for increased recombination.
Purpose of the Study:
- To test Holden's hypothesis regarding fitness interactions and recombination in partially selfing populations.
- To investigate the role of a third locus in controlling recombination rates.
- To determine if population mean fitness changes reliably indicate selection direction on recombination.
Main Methods:
- Employed algebraic calculations to model genetic dynamics.
- Utilized computer simulations to analyze allele fate at a third locus.
- Examined the relationship between recombination fraction and population mean fitness.
Main Results:
- Confirmed that specific fitness interactions can indeed select for increased recombination in partially selfing populations.
- Demonstrated that alleles at a third locus can modulate recombination levels between interacting loci.
- Found that population mean fitness trends do not consistently predict the direction of selection on recombination.
Conclusions:
- The study provides empirical support for theoretical predictions on recombination evolution under partial selfing.
- Highlights the importance of considering multi-locus interactions and modifier loci in population genetics.
- Warns against using population mean fitness alone to infer selection pressures on recombination rates.
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