期刊
GENETICS
卷 203, 期 2, 页码 959-+出版社
OXFORD UNIV PRESS INC
DOI: 10.1534/genetics.116.188821
关键词
adaptation; selection interference; dominance; self-fertilization; recombination
资金
- Centre National de la Recherche Scientifique (CNRS)
- Institut National de la Sante et de la Recherche Medicale (INSERM)
- Marie Curie International Outgoing Fellowship grant [MC-IOF-622936]
- CNRS
- Institut de Recherche pour le Developpement (IRD)
- French CNRS
- Marie Curie Intra-European Fellowship [IEF-623486]
- Agence Nationale de la Recherche (TRANS) [ANR-11-BSV7-013-03]
- Agence Nationale de la Recherche (SEAD) [ANR-13-ADAP-0011]
- Agence Nationale de la Recherche (ANR) [ANR-13-ADAP-0011] Funding Source: Agence Nationale de la Recherche (ANR)
In outcrossing populations, Haldane's sieve states that recessive beneficial alleles are less likely to fix than dominant ones, because they are less exposed to selection when rare. In contrast, selfing organisms are not subject to Haldane's sieve and are more likely to fix recessive types than outcrossers, as selfing rapidly creates homozygotes, increasing overall selection acting on mutations. However, longer homozygous tracts in selfers also reduce the ability of recombination to create new genotypes. It is unclear how these two effects influence overall adaptation rates in partially selfing organisms. Here, we calculate the fixation probability of beneficial alleles if there is an existing selective sweep in the population. We consider both the potential loss of the second beneficial mutation if it has a weaker advantage than the first one, and the possible replacement of the initial allele if the second mutant is fitter. Overall, loss of weaker adaptive alleles during a first selective sweep has a larger impact on preventing fixation of both mutations in highly selfing organisms. Furthermore, the presence of linked mutations has two opposing effects on Haldane's sieve. First, recessive mutants are disproportionally likely to be lost in outcrossers, so it is likelier that dominant mutations will fix. Second, with elevated rates of adaptive mutation, selective interference annuls the advantage in selfing organisms of not suffering from Haldane's sieve; outcrossing organisms are more able to fix weak beneficial mutations of any dominance value. Overall, weakened recombination effects can greatly limit adaptation in selfing organisms.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据