title: Evolvability of an Optimal Recombination Rate.
abstract: Evolution and maintenance of genetic recombination and its relation to the mutational process is a long-standing, fundamental problem in evolutionary biology that is linked to the general problem of evolution of evolvability. We explored a stochastic model of the evolution of recombination using additive fitness and infinite allele assumptions but no assumptions on the sign or magnitude of the epistasis and the distribution of mutation effects. In this model, fluctuating negative epistasis and predominantly deleterious mutations arise naturally as a consequence of the additive fitness and a reservoir from which new alleles arrive with a fixed distribution of fitness effects. Analysis of the model revealed a nonmonotonic effect of recombination intensity on fitness, with an optimal recombination rate value which maximized fitness in steady state. The optimal recombination rate depended on the mutation rate and was evolvable, that is, subject to selection. The predictions of the model were compatible with the observations on the dependence between genome rearrangement rate and gene flux in microbial genomes.
authors.affiliation: National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland.
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Lobkovsky
authors.affiliation: National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland.
authors.forename: Yuri I
authors.initials: YI
authors.lastname: Wolf
authors.affiliation: National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Maryland koonin@ncbi.nlm.nih.gov.
authors.forename: Eugene V
authors.initials: EV
authors.lastname: Koonin
mesh_terms: D020745:Genome, Archaeal; D016680:Genome, Bacterial; D008957:Models, Genetic; D059645:Mutation Rate; D011995:Recombination, Genetic
keywords: allele replacement; evolvability; gene flux; genome; rearrangement; recombination