The rate of adaptation in large sexual populations with linear chromosomes Journal Article

Author(s): Weissman, Daniel B; Hallatschek, Oskar
Article Title: The rate of adaptation in large sexual populations with linear chromosomes
Affiliation IST Austria
Abstract: In large populations, multiple beneficial mutations may be simultaneously spreading. In asexual populations, these mutations must either arise on the same background or compete against each other. In sexual populations, recombination can bring together beneficial alleles from different backgrounds, but tightly linked alleles may still greatly interfere with each other. We show for well-mixed populations that when this interference is strong, the genome can be seen as consisting of many effectively asexual stretches linked together. The rate at which beneficial alleles fix is thus roughly proportional to the rate of recombination and depends only logarithmically on the mutation supply and the strength of selection. Our scaling arguments also allow us to predict, with reasonable accuracy, the fitness distribution of fixed mutations when the mutational effect sizes are broad. We focus on the regime in which crossovers occur more frequently than beneficial mutations, as is likely to be the case for many natural populations.
Keywords: Human; Population Genetics; Genome; genetic algorithm; priority journal; article; allele; genetic variability; natural population; gene mutation; sex chromosome; evolutionary adaptation; genetic parameters
Journal Title: Genetics
Volume: 196
Issue 4
ISSN: 0016-6731
Publisher: Genetics Society of America  
Date Published: 2014-04-01
Start Page: 1167
End Page: 1183
Sponsor: D.B.W. received financial support from European Research Council grant 250152. O.H. received financial support from the German Research Foundation, within the Programme 1590 “Probabilistic Structures in Evolution,” grant HA 5163/2-1.
DOI: 10.1534/genetics.113.160705
Notes: We thank Nick Barton and Richard Neher for helpful discussions.
Open access: yes (repository)