Spontaneous mutations and the origin and maintenance of quantitative genetic variation

  1. Wen Huang
  2. Richard F Lyman
  3. Rachel A Lyman
  4. Mary Anna Carbone
  5. Susan T Harbison
  6. Michael M Magwire
  7. Trudy FC Mackay  Is a corresponding author
  1. North Carolina State University, United States
  2. Washington University in St. Louis, United States
  3. National Heart Lung and Blood Institute, United States
  4. Syngenta, United States

Abstract

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.

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Author details

  1. Wen Huang

    Program in Genetics, North Carolina State University, Raleigh, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Richard F Lyman

    Program in Genetics, North Carolina State University, Raleigh, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Rachel A Lyman

    Department of Biology, Washington University in St. Louis, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Mary Anna Carbone

    Program in Genetics, North Carolina State University, Raleigh, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Susan T Harbison

    Laboratory of Systems Genetics, National Heart Lung and Blood Institute, Bethesda, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Michael M Magwire

    Syngenta, Research Triangle Park, United States
    Competing interests
    The authors declare that no competing interests exist.
  7. Trudy FC Mackay

    Program in Genetics, North Carolina State University, Raleigh, United States
    For correspondence
    trudy_mackay@ncsu.edu
    Competing interests
    The authors declare that no competing interests exist.

Reviewing Editor

  1. Molly Przeworski, Columbia University, United States

Publication history

  1. Received: January 21, 2016
  2. Accepted: May 21, 2016
  3. Accepted Manuscript published: May 23, 2016 (version 1)
  4. Version of Record published: June 16, 2016 (version 2)
  5. Version of Record updated: October 19, 2016 (version 3)

Copyright

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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  1. Wen Huang
  2. Richard F Lyman
  3. Rachel A Lyman
  4. Mary Anna Carbone
  5. Susan T Harbison
  6. Michael M Magwire
  7. Trudy FC Mackay
(2016)
Spontaneous mutations and the origin and maintenance of quantitative genetic variation
eLife 5:e14625.
https://doi.org/10.7554/eLife.14625

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