PT  - JOURNAL ARTICLE
AU  - Paul Battlay
AU  - Sam Yeaman
AU  - Kathryn A. Hodgins
TI  - Pleiotropy drives repeatability in the genetic basis of adaptation
AID  - 10.1101/2021.09.13.459985
DP  - 2022 Jan 01
TA  - bioRxiv
PG  - 2021.09.13.459985
4099  - http://biorxiv.org/content/early/2022/09/26/2021.09.13.459985.1.short
4100  - http://biorxiv.org/content/early/2022/09/26/2021.09.13.459985.1.full
AB  - Studies of trait-mapping and local adaptation often identify signatures of genetically parallel evolution, where different species evolve similar phenotypes using the same genes. Such patterns appear incongruent with current estimations of quantitative trait architecture. With hundreds or thousands or genes contributing to a trait, why would selection make repeated use of the same genes? Here, we use individual-based simulations to explore a two-patch model with quantitative traits and pleiotropy to understand the parameters which may lead to repeated use of a particular locus during independent bouts of adaptation. We find that repeatability can be driven by increased phenotypic effect size, a reduction in trait dimensionality and a reduction in mutational correlations at a particular locus relative to other loci in the genome, and that these patterns are magnified by increased migration between demes. These results suggest that evolutionary convergence can arise from multiple characteristics of a locus, and provide a framework for the interpretation of quantitative signatures of convergence in empirical studies.Competing Interest StatementThe authors have declared no competing interest.