Spontaneous mutations and the origin and maintenance of quantitative genetic variation
Mutation and natural selection shape the genetic variation in natural populations. Here, we directly estimated the spontaneous mutation rate by sequencing new Drosophila mutation accumulation lines maintained with minimal natural selection. We inferred strong stabilizing natural selection on quantitative traits because genetic variation among wild-derived inbred lines was much lower than predicted from a neutral model and the mutational effects were much larger than allelic effects of standing polymorphisms. Stabilizing selection could act directly on the traits, or indirectly from pleiotropic effects on fitness. However, our data are not consistent with simple models of mutation-stabilizing selection balance; therefore, further empirical work is needed to assess the balance of evolutionary forces responsible for quantitative genetic variation.
Article and author information
- Molly Przeworski, Columbia University, United States
- Received: January 21, 2016
- Accepted: May 21, 2016
- Accepted Manuscript published: May 23, 2016 (version 1)
- Version of Record published: June 16, 2016 (version 2)
- Version of Record updated: October 19, 2016 (version 3)
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
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