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Title: Fitness maps to a large-effect locus in introduced stickleback populations
Significance

The role of mutations of large effect in adaptive evolution is a question of enduring interest. Large-effect mutations were once seen as unlikely contributors to adaptation, but we now have numerous examples. A major shortcoming of the evidence is the lack of information on fitness effects of mutations. We conducted a quantitative trait locus study that mapped fitness in an experimental field population of stickleback to a large-effect gene,Ectodysplasin(Eda). We compared this result with allele frequency change at the gene in a young lake population, which also revealed strong natural selection and large fitness effects of theEdagene and/or linked genes. Selection on ancient genetic variants may increase the prevalence of large-effect fitness variants in adaptive evolution.

 
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PAR ID:
10209141
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Proceedings of the National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
118
Issue:
3
ISSN:
0027-8424
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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