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Updated: May 21, 2026
07:54
Manipulation of Ploidy in Caenorhabditis elegans
Published on: March 15, 2018
Extending coalescent theory to autotetraploids.
B Arnold1, K Bomblies, J Wakeley
1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts 02138, USA. barnold@oeb.harvard.edu
Genetics
|June 21, 2012
Summary
We developed coalescent models for autotetraploid species, simplifying ancestral genetic studies. These models approximate population history using Kingman
Area of Science:
- Population genetics
- Evolutionary biology
- Genomics
Background:
- Autotetraploid species with tetrasomic inheritance present unique challenges for population genetic modeling.
- Existing coalescent models are primarily designed for diploid organisms.
Purpose of the Study:
- To develop and validate coalescent models for autotetraploid species with tetrasomic inheritance.
- To adapt existing coalescent theory for studying the population history of autotetraploids.
Main Methods:
- Development of coalescent models tailored for tetrasomic inheritance.
- Approximation of ancestral genetic processes using Kingman's standard coalescent.
- Numerical simulations to assess model accuracy.
Main Results:
- The ancestral genetic process in large, non-recombining autotetraploid populations can be approximated by Kingman's coalescent with an effective population size of 4N.
- This approximation is accurate for population sizes in the hundreds.
- The effects of double reduction are comparable to partial self-fertilization in polysomic inheritance.
Conclusions:
- Existing coalescent simulation software can be utilized for autotetraploid population history studies by adjusting the timescale.
- The developed models provide a framework for understanding the evolutionary dynamics of autotetraploid species.
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The homologous pairs of sister chromosomes—one from the maternal and one from the paternal genome—then begin to align alongside each other lengthwise, matching corresponding DNA positions in a process called synapsis.
In order to...