---
_id: '3303'
abstract:
- lang: eng
  text: 'Biological traits result in part from interactions between different genetic
    loci. This can lead to sign epistasis, in which a beneficial adaptation involves
    a combination of individually deleterious or neutral mutations; in this case,
    a population must cross a “fitness valley” to adapt. Recombination can assist
    this process by combining mutations from different individuals or retard it by
    breaking up the adaptive combination. Here, we analyze the simplest fitness valley,
    in which an adaptation requires one mutation at each of two loci to provide a
    fitness benefit. We present a theoretical analysis of the effect of recombination
    on the valley-crossing process across the full spectrum of possible parameter
    regimes. We find that low recombination rates can speed up valley crossing relative
    to the asexual case, while higher recombination rates slow down valley crossing,
    with the transition between the two regimes occurring when the recombination rate
    between the loci is approximately equal to the selective advantage provided by
    the adaptation. In large populations, if the recombination rate is high and selection
    against single mutants is substantial, the time to cross the valley grows exponentially
    with population size, effectively meaning that the population cannot acquire the
    adaptation. Recombination at the optimal (low) rate can reduce the valley-crossing
    time by up to several orders of magnitude relative to that in an asexual population. '
acknowledgement: "This work was supported in part by a Robert N. Noyce Stanford Graduate
  Fellowship and European Research Council grant 250152 (to D.B.W.) and by National
  Institutes of Health grant GM 28016 (to M.W.F.).\r\nWe thank Michael Desai for many
  ideas and discussions and are grateful to Joanna Masel and an anonymous reviewer
  for their helpful suggestions. "
article_processing_charge: No
author:
- first_name: Daniel
  full_name: Weissman, Daniel
  id: 2D0CE020-F248-11E8-B48F-1D18A9856A87
  last_name: Weissman
- first_name: Marcus
  full_name: Feldman, Marcus
  last_name: Feldman
- first_name: Daniel
  full_name: Fisher, Daniel
  last_name: Fisher
citation:
  ama: Weissman D, Feldman M, Fisher D. The rate of fitness-valley crossing in sexual
    populations. <i>Genetics</i>. 2010;186(4):1389-1410. doi:<a href="https://doi.org/10.1534/genetics.110.123240">10.1534/genetics.110.123240</a>
  apa: Weissman, D., Feldman, M., &#38; Fisher, D. (2010). The rate of fitness-valley
    crossing in sexual populations. <i>Genetics</i>. Genetics Society of America.
    <a href="https://doi.org/10.1534/genetics.110.123240">https://doi.org/10.1534/genetics.110.123240</a>
  chicago: Weissman, Daniel, Marcus Feldman, and Daniel Fisher. “The Rate of Fitness-Valley
    Crossing in Sexual Populations.” <i>Genetics</i>. Genetics Society of America,
    2010. <a href="https://doi.org/10.1534/genetics.110.123240">https://doi.org/10.1534/genetics.110.123240</a>.
  ieee: D. Weissman, M. Feldman, and D. Fisher, “The rate of fitness-valley crossing
    in sexual populations,” <i>Genetics</i>, vol. 186, no. 4. Genetics Society of
    America, pp. 1389–1410, 2010.
  ista: Weissman D, Feldman M, Fisher D. 2010. The rate of fitness-valley crossing
    in sexual populations. Genetics. 186(4), 1389–1410.
  mla: Weissman, Daniel, et al. “The Rate of Fitness-Valley Crossing in Sexual Populations.”
    <i>Genetics</i>, vol. 186, no. 4, Genetics Society of America, 2010, pp. 1389–410,
    doi:<a href="https://doi.org/10.1534/genetics.110.123240">10.1534/genetics.110.123240</a>.
  short: D. Weissman, M. Feldman, D. Fisher, Genetics 186 (2010) 1389–1410.
corr_author: '1'
date_created: 2018-12-11T12:02:33Z
date_published: 2010-12-01T00:00:00Z
date_updated: 2025-09-30T09:47:59Z
day: '01'
department:
- _id: NiBa
doi: 10.1534/genetics.110.123240
ec_funded: 1
external_id:
  isi:
  - '000285297000025'
intvolume: '       186'
isi: 1
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2998319/
month: '12'
oa: 1
oa_version: Submitted Version
page: 1389 - 1410
project:
- _id: 25B07788-B435-11E9-9278-68D0E5697425
  call_identifier: FP7
  grant_number: '250152'
  name: Limits to selection in biology and in evolutionary computation
publication: Genetics
publication_status: published
publisher: Genetics Society of America
publist_id: '3337'
quality_controlled: '1'
scopus_import: '1'
status: public
title: The rate of fitness-valley crossing in sexual populations
type: journal_article
user_id: 317138e5-6ab7-11ef-aa6d-ffef3953e345
volume: 186
year: '2010'
...