Data from: Sex-dependent dominance at a single locus maintains variation in age at maturity in salmon

Males and females share many traits that have a common genetic basis;
however, selection on these traits often differs between the sexes,
leading to sexual conflict. Under such sexual antagonism, theory predicts
the evolution of genetic architectures that resolve this sexual conflict.
Yet, despite intense theoretical and empirical interest, the specific loci
underlying sexually antagonistic phenotypes have rarely been identified,
limiting our understanding of how sexual conflict impacts genome evolution
and the maintenance of genetic diversity. Here we identify a large effect
locus controlling age at maturity in Atlantic salmon (Salmo salar), an
important fitness trait in which selection favours earlier maturation in
males than females and show it is a clear example of sex-dependent
dominance that reduces intralocus sexual conflict and maintains adaptive
variation in wild populations. Using high-density single nucleotide
polymorphism data across 57 wild populations and whole genome
re-sequencing, we find that the vestigial-like family member 3 gene
(VGLL3) exhibits sex-dependent dominance in salmon, promoting earlier and
later maturation in males and females, respectively. VGLL3, an adiposity
regulator associated with size and age at maturity in humans, explained
39% of phenotypic variation, an unexpectedly large proportion for what is
usually considered a highly polygenic trait. Such large effects are
predicted under balancing selection from either sexually antagonistic or
spatially varying selection. Our results provide the first empirical
example of dominance reversal allowing greater optimization of phenotypes
within each sex, contributing to the resolution of sexual conflict in a
major and widespread evolutionary trade-off between age and size at
maturity. They also provide key empirical evidence for how variation in
reproductive strategies can be maintained over large geographical scales.
We anticipate these findings will have a substantial impact on population
management in a range of harvested species where trends towards earlier
maturation have been observed.