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Updated: Jul 15, 2026
06:18
Frequency and Distribution of Crossovers in Caenorhabditis elegans Meiosis by SNP Genotyping using Real-time PCR
Published on: July 11, 2025
Transposable elements, mutational correlations, and population divergence in Caenorhabditis elegans.
Mattieu Bégin1, Daniel J Schoen
1Department of Biology, McGill University, 1205 Dr. Penfield Avenue, Montréal, Québec, H3A 1B1, Canada.
Summary
Transposable elements increase mutation rates and heritability in Caenorhabditis elegans. However, population divergence is shaped by mutation, selection, and drift, not solely by mobile element activity.
Area of Science:
- Evolutionary biology
- Genetics
- Molecular biology
Background:
- Transposable element activity is a significant source of mutations.
- The impact of transposable elements on population evolution is not well understood.
Purpose of the Study:
- Investigate the effect of transposable element activity on mutational variances and covariances.
- Determine if mutational covariation patterns predict population divergence in Caenorhabditis elegans.
Main Methods:
- Mutation accumulation experiments using RNAi-deficient mutator strains and a non-transposing strain of Caenorhabditis elegans.
- Analysis of mutational heritabilities and covariances.
- Comparison of mutational patterns with divergence patterns in 15 natural populations.
Main Results:
- Transposition increased mutational heritabilities and intensified correlation patterns.
- Mutations generally had a deleterious effect on fitness components; no trade-offs were detected.
- Population divergence in phenotypic space was only partially concordant with mutation patterns.
Conclusions:
- Transposable element-induced mutations in C. elegans contribute to microevolution of quantitative traits similarly to other spontaneous mutations.
- Natural selection and genetic drift play crucial roles in shaping population divergence alongside mutation.
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