title: Extent of QTL Reuse During Repeated Phenotypic Divergence of Sympatric Threespine Stickleback.
abstract: How predictable is the genetic basis of phenotypic adaptation? Answering this question begins by estimating the repeatability of adaptation at the genetic level. Here, we provide a comprehensive estimate of the repeatability of the genetic basis of adaptive phenotypic evolution in a natural system. We used quantitative trait locus (QTL) mapping to discover genomic regions controlling a large number of morphological traits that have diverged in parallel between pairs of threespine stickleback (Gasterosteus aculeatus species complex) in Paxton and Priest lakes, British Columbia. We found that nearly half of QTL affected the same traits in the same direction in both species pairs. Another 40% influenced a parallel phenotypic trait in one lake but not the other. The remaining 10% of QTL had phenotypic effects in opposite directions in the two species pairs. Similarity in the proportional contributions of all QTL to parallel trait differences was about 0.4. Surprisingly, QTL reuse was unrelated to phenotypic effect size. Our results indicate that repeated use of the same genomic regions is a pervasive feature of parallel phenotypic adaptation, at least in sticklebacks. Identifying the causes of this pattern would aid prediction of the genetic basis of phenotypic evolution.
authors.affiliation: Biodiversity Research Centre and Zoology Department, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4 conte@zoology.ubc.ca.
authors.forename: Gina L
authors.identifier: http://orcid.org/0000-0003-0215-0777
authors.initials: GL
authors.lastname: Conte
authors.affiliation: Biodiversity Research Centre and Zoology Department, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4 Divisions of Human Biology and Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024.
authors.forename: Matthew E
authors.initials: ME
authors.lastname: Arnegard
authors.affiliation: Biodiversity Research Centre and Zoology Department, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.
authors.forename: Jacob
authors.initials: J
authors.lastname: Best
authors.affiliation: Department of Developmental Biology and Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California 94305-5329.
authors.forename: Yingguang Frank
authors.initials: YF
authors.lastname: Chan
authors.affiliation: Department of Developmental Biology and Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California 94305-5329.
authors.forename: Felicity C
authors.initials: FC
authors.lastname: Jones
authors.affiliation: Department of Developmental Biology and Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California 94305-5329.
authors.forename: David M
authors.initials: DM
authors.lastname: Kingsley
authors.affiliation: Biodiversity Research Centre and Zoology Department, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4.
authors.forename: Dolph
authors.initials: D
authors.lastname: Schluter
authors.affiliation: Divisions of Human Biology and Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109-1024.
authors.forename: Catherine L
authors.initials: CL
authors.lastname: Peichel
mesh_terms: D000220:Adaptation, Biological; D000818:Animals; D005260:Female; D049810:Genetic Speciation; D008297:Male; D010641:Phenotype; D040641:Quantitative Trait Loci; D023701:Smegmamorpha / Q000235:genetics*; D061350:Sympatry
keywords: QTL mapping; genetic parallelism; genetics of adaptation; parallel evolution; repeated evolution