1. Computational and Systems Biology
  2. Genetics and Genomics
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Intrinsic adaptive value and early fate of gene duplication revealed by a bottom-up approach

  1. Guillermo Rodrigo  Is a corresponding author
  2. Mario A Fares
  1. CSIC - UPV, Spain
Research Article
  • Cited 9
  • Views 1,549
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Cite this article as: eLife 2018;7:e29739 doi: 10.7554/eLife.29739

Abstract

The population genetic mechanisms governing the preservation of gene duplicates, especially in the critical very initial phase, have remained largely unknown. Here, we demonstrate that gene duplication confers per se a weak selective advantage in scenarios of fitness trade-offs. Through a precise quantitative description of a model system, we show that a second gene copy serves to reduce gene expression inaccuracies derived from pervasive molecular noise and suboptimal gene regulation. We then reveal that such an accuracy in the phenotype yields a selective advantage in the order of 0.1% on average, which would allow the positive selection of gene duplication in populations with moderate/large sizes. This advantage is greater at higher noise levels and intermediate concentrations of the environmental molecule, when fitness trade-offs become more evident. Moreover, we discuss how the genome rearrangement rates greatly condition the eventual fixation of duplicates. Overall, our theoretical results highlight an original adaptive value for cells carrying new-born duplicates, broadly analyze the selective conditions that determine their early fates in different organisms, and reconcile population genetics with evolution by gene duplication.

Article and author information

Author details

  1. Guillermo Rodrigo

    Instituto de Biología Molecular y Celular de Plantas, CSIC - UPV, Valencia, Spain
    For correspondence
    guillermo.rodrigo@csic.es
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-1871-9617
  2. Mario A Fares

    Instituto de Biología Molecular y Celular de Plantas, CSIC - UPV, Valencia, Spain
    Competing interests
    The authors declare that no competing interests exist.

Funding

Ministerio de Economía y Competitividad (BFU2015-66894-P)

  • Guillermo Rodrigo

Ministerio de Economía y Competitividad (BFU2015-66073-P)

  • Mario A Fares

Generalitat Valenciana (GVA/2016/079)

  • Guillermo Rodrigo

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Diethard Tautz, Max-Planck Institute for Evolutionary Biology, Germany

Publication history

  1. Received: June 20, 2017
  2. Accepted: January 4, 2018
  3. Accepted Manuscript published: January 5, 2018 (version 1)
  4. Version of Record published: January 17, 2018 (version 2)

Copyright

© 2018, Rodrigo & Fares

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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Further reading

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