Evolutionary traction: the cost of adaptation and the evolution of sex

Hadany, Lilach; Feldman, M. W.

doi:10.1111/j.1420-9101.2004.00858.x

Cited by 37 publications

(37 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The increase in modifier fixation with higher s a is likely to arise because strongly favored mutants are likely to carry along with them many deleterious mutations in the absence of recombination (Peck 1994;Hadany and Feldman 2005) and recombination can free these advantageous mutations from their deleterious backgrounds. In line with this reasoning, Table 1 shows that for N ¼ 1000 and U ¼ 0.5, re- combination aids the fixation of advantageous mutants and decreases the fixation rate of deleterious mutants in all cases simulated.…”

Section: Resultsmentioning

confidence: 99%

“…Furthermore, if background deleterious mutations are frequent, recombination has an extra advantage in aiding purifying selection and is even more likely to evolve than in the presence of beneficial mutations alone. Such a scenario was discussed by Hadany and Feldman (2005) and could explain why recombination is more likely to occur in new, stressed environments (Abdullah and Borts 2001;Grishkan et al 2003).…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

The Role of Advantageous Mutations in Enhancing the Evolution of a Recombination Modifier

2010

View full text Add to dashboard Cite

Although the evolution of recombination is still a major problem in evolutionary genetics, recent theoretical studies have shown that recombination can evolve by breaking down interference (''HillRobertson effects'') among multiple loci. This leads to selection on a recombination modifier in a population subject to recurrent deleterious mutation. Here, we use computer simulations to investigate the evolution of a recombination modifier under three different scenarios of recurrent mutation in a finite population: (1) mutations are deleterious only, (2) mutations are advantageous only, and (3) there is a mixture of deleterious and advantageous mutations. We also investigate how linkage disequilibrium, the strength of selection acting on a modifier, and effective population size change under the different scenarios. We observe that adding even a small number of advantageous mutations increases the fixation rate of modifiers that increase recombination, especially if the effects of deleterious mutations are weak. However, the strength of selection on a modifier is less than the summed strengths had there been deleterious mutations only and advantageous mutations only.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

The Role of Advantageous Mutations in Enhancing the Evolution of a Recombination Modifier

2010

View full text Add to dashboard Cite

show abstract

“…This "Hill−Robertson" or "linkage" interference can be alleviated by recombination, allowing adaptive mutations to combine onto the same background or escape deleterious neighbors (31)(32)(33)(34)(35). In addition to affecting the rate of fixation of beneficial mutations, a deleterious mutation genetically linked to a beneficial mutation can "hitchhike" to high frequency or even fixation (36,37). These theoretical predictions are beginning to be borne out in empirical data (38)(39)(40)(41)(42)(43)(44)(45)(46)(47).…”

mentioning

confidence: 99%

Obstruction of adaptation in diploids by recessive, strongly deleterious alleles

Assaf¹,

Petrov²,

Blundell

2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

Recessive deleterious mutations are common, causing many genetic disorders in humans and producing inbreeding depression in the majority of sexually reproducing diploids. The abundance of recessive deleterious mutations in natural populations suggests they are likely to be present on a chromosome when a new adaptive mutation occurs, yet the dynamics of recessive deleterious hitchhikers and their impact on adaptation remains poorly understood. Here we model how a recessive deleterious mutation impacts the fate of a genetically linked dominant beneficial mutation. The frequency trajectory of the adaptive mutation in this case is dramatically altered and results in what we have termed a "staggered sweep." It is named for its threephased trajectory: (i) Initially, the two linked mutations have a selective advantage while rare and will increase in frequency together, then (ii), at higher frequencies, the recessive hitchhiker is exposed to selection and can cause a balanced state via heterozygote advantage (the staggered phase), and (iii) finally, if recombination unlinks the two mutations, then the beneficial mutation can complete the sweep to fixation. Using both analytics and simulations, we show that strongly deleterious recessive mutations can substantially decrease the probability of fixation for nearby beneficial mutations, thus creating zones in the genome where adaptation is suppressed. These mutations can also significantly prolong the number of generations a beneficial mutation takes to sweep to fixation, and cause the genomic signature of selection to resemble that of soft or partial sweeps. We show that recessive deleterious variation could impact adaptation in humans and Drosophila.I n diploids, the fitness effect of having a single copy of a mutation depends not only on the mutation's selective effect, s, but also on its heterozygous effect, h. A fully recessive mutation (h = 0) is hidden in the heterozygote (hs = 0), and a fully dominant mutation (h = 1) is completely exposed (hs = s). Although it is generally agreed that beneficial mutations that reach fixation tend to be dominant (i.e., h ≥ 0.5) (1, 2), both empirical data and theoretical models (3-6) suggest that many strongly and even moderately deleterious mutations are likely to be recessive (i.e., h < 0.5). For example, studies of de novo mutations from both mutation accumulation and mutagenesis experiments in Drosophila melanogaster, Saccharomyces cerevisiae, and Caenorhabditis elegans have repeatedly found that strongly deleterious mutations tend to be completely recessive (h ≈ 0) and more weakly deleterious mutations tend to be partially recessive (h ≈ 0.1) (7-13). Furthermore, studies of natural populations have found that inbreeding depression is pervasive across sexually reproducing diploids and is mainly caused by recessive deleterious variation (reviewed in ref. 14). For example, in natural populations of Drosophila, approximately 30% of chromosomes carry a recessive lethal, and chromosomes that do not carry a recessive lethal suffer fro...

show abstract

“…The majority of studies on the evolution of sex focus either on the evolution of recombination rates (see reviews by Feldman et al 1996;Barton and Charlesworth 1998;Otto and Lenormand 2002) or on the long-term consequences of sex to the mean fitness and competitive ability of a population (e.g., Muller 1964;Kimura and Maruyama 1966;Kondrashov 1988;Howard and Lively 1994;Peck et al 1997;Chasnov 2000;Agrawal and Chasnov 2001;Hadany and Feldman 2005). Fully understanding the evolution and maintenance of sex, however, requires that we consider populations capable of both sexual and asexual reproduction and investigate when increased investment in sexual reproduction can evolve.…”

mentioning

confidence: 99%

The Evolution of Condition-Dependent Sex in the Face of High Costs

Hadany

Otto

2007

Genetics

View full text Add to dashboard Cite

Facultatively sexual organisms often engage in sex more often when in poor condition. We show that such condition-dependent sex carries evolutionary advantages and can explain the evolution of sexual reproduction even when sex entails high costs. Specifically, we show that alleles promoting individuals of low fitness to have sex more often than individuals of high fitness spread through a population. Such alleles are more likely to segregate out of bad genetic backgrounds and onto good genetic backgrounds, where they tend to remain. This ''abandon-ship'' mechanism provides a plausible model for the evolution and maintenance of facultative sex.

show abstract

Evolutionary traction: the cost of adaptation and the evolution of sex

Cited by 37 publications

References 34 publications

The Role of Advantageous Mutations in Enhancing the Evolution of a Recombination Modifier

The Role of Advantageous Mutations in Enhancing the Evolution of a Recombination Modifier

Obstruction of adaptation in diploids by recessive, strongly deleterious alleles

The Evolution of Condition-Dependent Sex in the Face of High Costs

Contact Info

Product

Resources

About