The fixation probability and time for a doubly beneficial mutant

Bossert, Sebastian; Pfaffelhuber, Peter

doi:10.1016/j.spa.2018.01.004

Cited by 4 publications

(10 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…in a series of mathematical papers (Bossert & Pfaffelhuber, 2018;Cuthbertson et al, 2012;Yu & Etheridge, 2010). However, the pattern of variation in genetic data for such a model of competing sweeps is largely unknown.…”

Section: Discussionmentioning

confidence: 99%

“…If A and B can recombine at some rate, there is a chance that the double beneficial mutant AB forms and eventually fixes. Basic questions such as the fixation probability of AB and its fixation time have been addressed in a series of mathematical papers (Bossert & Pfaffelhuber, 2018 ; Cuthbertson et al, 2012 ; Yu & Etheridge, 2010 ). However, the pattern of variation in genetic data for such a model of competing sweeps is largely unknown.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

The classical hitchhiking model with continuous mutational pressure and purifying selection

Stephan

2021

Ecology and Evolution

View full text Add to dashboard Cite

Detecting selective sweeps driven by strong positive selection and localizing the targets of selection in the genome play a major role in modern population genetics and genomics. Most of these analyses are based on the classical model of genetic hitchhiking proposed by Maynard Smith and Haigh (1974, Genetical Research, 23, 23). Here, we consider extensions of the classical two‐locus model. Introducing mutation at the strongly selected site, we analyze the conditions under which soft sweeps may arise. We identify a new parameter (the ratio of the beneficial mutation rate to the selection coefficient) that characterizes the occurrence of multiple‐origin soft sweeps. Furthermore, we quantify the hitchhiking effect when the polymorphism at the linked locus is not neutral but maintained in a mutation‐selection balance. In this case, we find a smaller relative reduction of heterozygosity at the linked site than for a neutral polymorphism. In our analysis, we use a semi‐deterministic approach; i.e., we analyze the frequency process of the beneficial allele in an infinitely large population when its frequency is above a certain threshold; however, for very small frequencies in the initial phase after the onset of selection we rely on diffusion theory.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

The classical hitchhiking model with continuous mutational pressure and purifying selection

Stephan

2021

Ecology and Evolution

View full text Add to dashboard Cite

show abstract

“…Next, I will discuss the case in which selective sweeps along the genome do not occur sequentially, but interfere with each other. Such evolutionary traffic of interfering positive fixations has been described by several authors (Barton 1995;Kirby and Stephan 1996;Yu and Etheridge 2010;Bossert and Pfaffelhuber 2016), but the impact on linked neutral variation is not well understood. To my knowledge, only two studies have modeled genetic hitchhiking in the presence of interference between partially linked beneficial alleles on their way to fixation.…”

Section: Competing Selective Sweepsmentioning

confidence: 93%

Selective Sweeps

2019

View full text Add to dashboard Cite

For almost 20 years, many inference methods have been developed to detect selective sweeps and localize the targets of directional selection in the genome. These methods are based on population genetic models that describe the effect of a beneficial allele (e.g., a new mutation) on linked neutral variation (driven by directional selection from a single copy to fixation). Here, I discuss these models, ranging from selective sweeps in a panmictic population of constant size to evolutionary traffic when simultaneous sweeps at multiple loci interfere, and emphasize the important role of demography and population structure in data analysis. In the past 10 years, soft sweeps that may arise after an environmental change from directional selection on standing variation have become a focus of population genetic research. In contrast to selective sweeps, they are caused by beneficial alleles that were neutrally segregating in a population before the environmental change or were present at a mutation-selection balance in appreciable frequency.

show abstract

“…Here, we note that this solution to the system of ODEs was not given in an explicit form. Bossert and Pfaffelhuber (2018) considered a diffusion model with four types: ab, Ab, aB, and AB, where the fitnesses of ab, Ab, aB, and AB are in increasing order. The frequencies of these four types evolve according to a system of SDEs.…”

Section: Introductionmentioning

confidence: 99%

“…Both Cuthbertson et al (2012) and Bossert and Pfaffelhuber (2018) assume that at least one beneficial mutation is present at the beginning and do not allow an unlimited supply of new mutations. In contrast, our model assumes that all individuals do not have any beneficial mutations in the beginning, and both beneficial mutations occur according to a Poisson process.…”

Section: Introductionmentioning

confidence: 99%

The Effect of Recombination on the Speed of Evolution

Udomchatpitak¹

2021

ALEA

View full text Add to dashboard Cite

It has been a puzzling question of why sexual reproduction has been so successful. Fisher and Muller hypothesized that reproducing by sex can speed up evolution; recombination could combine beneficial alleles on different chromosomes and speeds up the time that the beneficial alleles become fixated population. We consider a population of 2N chromosomes and focus on two loci on these chromosomes. The allele at each locus can mutate to a beneficial allele at rate µ N. Chromosomes with 0, 1, and 2 beneficial alleles die at rates 1, 1 − s N , and 1 − 2s N , respectively, and they are replaced immediately after death events. With probability 1 − r N , the replacement inherits both alleles from one parent chosen at random from the population at the time of replacement. With probability r N , recombination occurs, and the replacement receives its two alleles from two randomly chosen parents. Under certain assumptions on the parameters N, µ N , s N , and r N , we obtain an asymptotic approximation to the time that both beneficial alleles are fixated in the population. When the recombination probability is small, recombination does not speed up the time that the two beneficial alleles become fixated. In contrast, when the recombination probability is significant, recombination shorten this time. The result agrees with the Fisher-Muller hypothesis and confirms the advantage of reproducing by sex.

show abstract

The fixation probability and time for a doubly beneficial mutant

Cited by 4 publications

References 37 publications

The classical hitchhiking model with continuous mutational pressure and purifying selection

The classical hitchhiking model with continuous mutational pressure and purifying selection

Selective Sweeps

The Effect of Recombination on the Speed of Evolution

Contact Info

Product

Resources

About