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Updated: May 26, 2026
04:52
Following the Dynamics of Structural Variants in Experimentally Evolved Populations
Published on: February 3, 2023
Coalescent patterns for chromosomal inversions in divergent populations
Rafael F Guerrero1, François Rousset, Mark Kirkpatrick
1Section of Integrative Biology, University of Texas, Austin, TX 78712, USA. r.guerrero@utexas.edu
Summary
Chromosomal inversions shape genetic divergence by limiting recombination. This study models their impact on neutral genetic diversity, revealing patterns influenced by inversion age and gene flow, crucial for understanding speciation.
Area of Science:
- Evolutionary genetics
- Population genetics
- Speciation research
Background:
- Chromosomal inversions reduce recombination, facilitating genetic divergence in locally adapted populations.
- Signatures of divergence and hybridization are expected in neutral genetic diversity within inverted regions.
- Quantitative predictions for these genetic patterns have been lacking.
Purpose of the Study:
- To develop coalescent models for neutral genetic diversity linked to inversion polymorphisms in two locally adapted populations.
- To investigate the impact of selection on inversion breakpoints versus alleles within inversions.
- To provide quantitative expectations for genetic signatures of inversions.
Main Methods:
- Development of coalescent models for neutral sites linked to inversion polymorphisms.
- Analysis of two scenarios: selection at breakpoints and selection within inversions.
- Inclusion of genetic drift effects on inversion patterns.
Main Results:
- Ancient inversion polymorphisms significantly alter neutral genetic diversity, deviating from neutral expectations.
- Patterns can be difficult to detect, depending on inversion age and gene flow rates.
- Inversions under genetic drift mimic patterns of intermediate-aged, locally adapted inversions.
Conclusions:
- The age of inversions and gene flow are critical factors determining detectable genetic signatures.
- Coalescent models provide a quantitative framework for analyzing inversion roles in speciation.
- Results align with empirical observations and advance speciation research.
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