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Updated: May 7, 2026
08:19
Quantitative Comparison of cis-Regulatory Element CRE Activities in Transgenic Drosophila melanogaster
Published on: December 19, 2011
11.3K
Recombination modulates how selection affects linked sites in Drosophila
Suzanne E McGaugh1, Caiti S S Heil, Brenda Manzano-Winkler
1Biology Department, Duke University, Durham, North Carolina, United States of America. suzanne.mcgaugh@duke.edu
Plos Biology
|November 16, 2012
Summary
Recombination positively impacts genetic diversity by modulating Hill-Robertson effects, not by being mutagenic. This study analyzed recombination rates in D. pseudoobscura and D. miranda to support this molecular evolution finding.
Area of Science:
- Molecular Evolution
- Population Genetics
- Genomics
Background:
- A strong association exists between local recombination rate and nucleotide polymorphisms, often attributed to natural selection.
- The mutagenic effect of recombination has been largely dismissed due to a lack of correlation with interspecies nucleotide divergence.
- Recent findings of differing recombination rates in closely related species challenge previous assumptions.
Purpose of the Study:
- To investigate the relationship between recombination rate and genetic diversity.
- To differentiate between selection-driven and mutation-driven explanations for recombination-diversity associations.
- To analyze recombination patterns in D. pseudoobscura and D. miranda.
Main Methods:
- Surveyed recombination across significant portions of the D. pseudoobscura and D. miranda genomes.
- Constructed two separate recombination maps for D. pseudoobscura.
- Utilized conserved recombination regions and controlled for covariates.
Main Results:
- Identified global and local differences in recombination rates between D. pseudoobscura and D. miranda.
- Demonstrated a positive relationship between recombination rate and genetic diversity.
- Observed dips in diversity around nonsynonymous substitutions, suggesting selective sweeps.
Conclusions:
- Recombination enhances genetic diversity primarily by modulating Hill-Robertson effects, rather than being mutagenic.
- Selective sweeps likely contribute to reduced diversity around nonsynonymous substitutions.
- Findings provide crucial insights into the forces shaping genome evolution.
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