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Updated: May 21, 2026

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
Abstract:
We develop coalescent models for autotetraploid species with tetrasomic inheritance. We show that the ancestral genetic process in a large population without recombination may be approximated using Kingman's standard coalescent, with a coalescent effective population size 4N. Numerical results suggest that this approximation is accurate for population sizes on the order of hundreds of individuals. Therefore, existing coalescent simulation programs can be adapted to study population history in autotetraploids simply by interpreting the timescale in units of 4N generations. We also consider the possibility of double reduction, a phenomenon unique to polysomic inheritance, and show that its effects on gene genealogies are similar to partial self-fertilization.
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