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Updated: Jun 21, 2026
07:54
Manipulation of Ploidy in Caenorhabditis elegans
Published on: March 15, 2018
Ploidy and the causes of genomic evolution
Aleeza C Gerstein1, Sarah P Otto
1Department of Zoology, University of British Columbia, Vancouver, British Columbia, V6T 1Z4, Canada. gerstein@zoology.ubc.ca
The Journal of Heredity
|July 24, 2009
Summary
Polyploidization, or whole-genome duplication, significantly impacts eukaryotic evolution. Experimental evolution in yeast reveals how ploidy affects fitness, mutation masking, adaptation rates, and the balance of selection versus drift.
Area of Science:
- Evolutionary Biology
- Genetics
- Molecular Biology
Background:
- Eukaryotic genomes exhibit substantial variation in size and content.
- Polyploidization events are a major driver of this genomic variation throughout evolution.
Purpose of the Study:
- To review experimental evolution studies investigating the consequences of polyploidization.
- To analyze the fitness effects of ploidy mutations, mutation masking, adaptation rates, and selection versus drift.
- To present new data on maximal growth rates across different ploidy levels.
Main Methods:
- Review of existing experimental evolution studies, primarily using Saccharomyces cerevisiae.
- Analysis of data concerning immediate fitness effects of ploidy mutations.
- Presentation of novel experimental data on maximal growth rates in relation to ploidy.
Main Results:
- Experimental evolution provides insights into how ploidy influences adaptation and the masking of deleterious mutations.
- Ploidy levels impact the interplay between selection and genetic drift in evolutionary trajectories.
- Differences in maximal growth rates were observed among cells with varying ploidy levels.
Conclusions:
- Polyploidization is a critical factor shaping eukaryotic genome evolution.
- Experimental evolution is a powerful tool for dissecting the adaptive and evolutionary consequences of ploidy.
- Ploidy level directly influences cellular fitness and growth rate, with implications for evolutionary dynamics.
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The duplicated copies of the gene are called Paralogs. Paralogs with similar sequences and functions form a gene family. Across several species, a large number of gene families are characterized.
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