Coalescence and genetic diversity in sexual populations under selection
| Autor: | Taylor A. Kessinger, Boris I. Shraiman, Richard A. Neher |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2013 |
| Předmět: |
Linkage disequilibrium
Genetic Fitness Population genetics Unit of selection Biology Linkage Disequilibrium 03 medical and health sciences 0302 clinical medicine Genetic variation Humans Genetic variability Selection Genetic Quantitative Biology - Populations and Evolution 030304 developmental biology Recombination Genetic 0303 health sciences Genetic diversity Multidisciplinary Models Genetic Populations and Evolution (q-bio.PE) Genetic Variation Quantitative genetics Biological Sciences Adaptation Physiological Genetics Population Genetic Loci Evolutionary biology FOS: Biological sciences Mutation 030217 neurology & neurosurgery Genealogy and Heraldry |
| Zdroj: | Proceedings of the National Academy of Sciences |
| Popis: | In sexual populations, selection operates neither on the whole genome, which is repeatedly taken apart and reassembled by recombination, nor on individual alleles that are tightly linked to the chromosomal neighborhood. The resulting interference between linked alleles reduces the efficiency of selection and distorts patterns of genetic diversity. Inference of evolutionary history from diversity shaped by linked selection requires an understanding of these patterns. Here, we present a simple but powerful scaling analysis identifying the unit of selection as the genomic "linkage block" with a characteristic length, , determined in a self-consistent manner by the condition that the rate of recombination within the block is comparable to the fitness differences between different alleles of the block. We find that an asexual model with the strength of selection tuned to that of the linkage block provides an excellent description of genetic diversity and the site frequency spectra compared with computer simulations. This linkage block approximation is accurate for the entire spectrum of strength of selection and is particularly powerful in scenarios with many weakly selected loci. The latter limit allows us to characterize coalescence, genetic diversity, and the speed of adaptation in the infinitesimal model of quantitative genetics. |
| Databáze: | OpenAIRE |
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