Response to selection in finite locus models with nonadditive effects

Hadi Esfandyari*, Mark Henryon, Peer Berg, Jørn Rind Thomasen, Piter Bijma, Anders Christian Sørensen

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

3 Citations (Scopus)

Abstract

Under the finite-locus model in the absence of mutation, the additive genetic variation is expected to decrease when directional selection is acting on a population, according to quantitative-genetic theory. However, some theoretical studies of selection suggest that the level of additive variance can be sustained or even increased when nonadditive genetic effects are present. We tested the hypothesis that finite-locus models with both additive and nonadditive genetic effects maintain more additive genetic variance (VA) and realize larger medium-to long-term genetic gains than models with only additive effects when the trait under selection is subject to truncation selection. Four genetic models that included additive, dominance, and additive-by-additive epistatic effects were simulated. The simulated genome for individuals consisted of 25 chromosomes, each with a length of 1 M. One hundred bi-allelic QTL, 4 on each chromosome, were considered. In each generation, 100 sires and 100 dams were mated, producing 5 progeny per mating. The population was selected for a single trait (h2 = 0.1) for 100 discrete generations with selection on phenotype or BLUP-EBV. VA decreased with directional truncation selection even in presence of nonadditive genetic effects. Nonadditive effects influenced long-term response to selection and among genetic models additive gene action had highest response to selection. In addition, in all genetic models, BLUP-EBV resulted in a greater fixation of favorable and unfavorable alleles and higher response than phenotypic selection. In conclusion, for the schemes we simulated, the presence of nonadditive genetic effects had little effect in changes of additive variance and VA decreased by directional selection.

Original languageEnglish
Pages (from-to)318-327
JournalJournal of Heredity
Volume108
Issue number3
DOIs
Publication statusPublished - 2017

Keywords

  • Finite locus model
  • Nonadditive effects
  • Selection

Fingerprint Dive into the research topics of 'Response to selection in finite locus models with nonadditive effects'. Together they form a unique fingerprint.

  • Cite this

    Esfandyari, H., Henryon, M., Berg, P., Thomasen, J. R., Bijma, P., & Sørensen, A. C. (2017). Response to selection in finite locus models with nonadditive effects. Journal of Heredity, 108(3), 318-327. https://doi.org/10.1093/jhered/esw123