%0 Journal Article %1 devladar2014stability %A de Vladar, Harold P. %A Barton, Nick %D 2014 %I Genetics Society of America %J Genetics %K polygenic_adaptation polygenic_traits population_genetics quantitative_genetics quantitative_traits %N 2 %P 749--767 %R 10.1534/genetics.113.159111 %T Stability and Response of Polygenic Traits to Stabilizing Selection and Mutation %U https://doi.org/10.1534%2Fgenetics.113.159111 %V 197 %X When polygenic traits are under stabilizing selection, many different combinations of alleles allow close adaptation to the optimum. If alleles have equal effects, all combinations that result in the same deviation from the optimum are equivalent. Furthermore, the genetic variance that is maintained by mutation–selection balance is 2m= S per locus, where m is the mutation rate and S the strength of stabilizing selection. In reality, alleles vary in their effects, making the fitness landscape asymmetric and complicating analysis of the equilibria. We show that that the resulting genetic variance depends on the fraction of alleles near fixation, which contribute by 2m= S , and on the total mutational effects of alleles that are at intermediate frequency. The interplay p ffiffiffiffiffiffiffiffiffi between stabilizing selection and mutation leads to a sharp transition: alleles with effects smaller than a threshold value of 2 m= S remain polymorphic, whereas those with larger effects are fixed. The genetic load in equilibrium is less than for traits of equal effects, and the fitness equilibria are more similar. We find that p ffiffiffiffiffiffi if the optimum is displaced, alleles with effects close to the threshold value sweep first, and their rate of increase is bounded by m S : Long-term response leads in general to well-adapted traits, unlike the case of equal effects that often end up at a suboptimal fitness peak. However, the particular peaks to which the populations converge are extremely sensitive to the initial states and to the speed of the shift of the optimum trait value.

@article{devladar2014stability, abstract = {When polygenic traits are under stabilizing selection, many different combinations of alleles allow close adaptation to the optimum. If alleles have equal effects, all combinations that result in the same deviation from the optimum are equivalent. Furthermore, the genetic variance that is maintained by mutation–selection balance is 2m= S per locus, where m is the mutation rate and S the strength of stabilizing selection. In reality, alleles vary in their effects, making the fitness landscape asymmetric and complicating analysis of the equilibria. We show that that the resulting genetic variance depends on the fraction of alleles near fixation, which contribute by 2m= S , and on the total mutational effects of alleles that are at intermediate frequency. The interplay p ffiffiffiffiffiffiffiffiffi between stabilizing selection and mutation leads to a sharp transition: alleles with effects smaller than a threshold value of 2 m= S remain polymorphic, whereas those with larger effects are fixed. The genetic load in equilibrium is less than for traits of equal effects, and the fitness equilibria are more similar. We find that p ffiffiffiffiffiffi if the optimum is displaced, alleles with effects close to the threshold value sweep first, and their rate of increase is bounded by m S : Long-term response leads in general to well-adapted traits, unlike the case of equal effects that often end up at a suboptimal fitness peak. However, the particular peaks to which the populations converge are extremely sensitive to the initial states and to the speed of the shift of the optimum trait value.}, added-at = {2020-04-29T00:19:52.000+0200}, author = {de Vladar, Harold P. and Barton, Nick}, biburl = {https://www.bibsonomy.org/bibtex/22d7e5b3fd5cc04db3b268efa2641ffa3/peter.ralph}, doi = {10.1534/genetics.113.159111}, interhash = {0d4731d719f8b0b255b1a93313827155}, intrahash = {2d7e5b3fd5cc04db3b268efa2641ffa3}, journal = {Genetics}, keywords = {polygenic_adaptation polygenic_traits population_genetics quantitative_genetics quantitative_traits}, month = apr, number = 2, pages = {749--767}, publisher = {Genetics Society of America}, timestamp = {2020-04-29T00:19:52.000+0200}, title = {Stability and Response of Polygenic Traits to Stabilizing Selection and Mutation}, url = {https://doi.org/10.1534%2Fgenetics.113.159111}, volume = 197, year = 2014 }