Genes that affect Atlantic salmon growth in hatchery do not have the same effect in the wild

Dissecting the genetic mechanisms of phenotypic traits that influence fitness in diverse environments provides the important first step towards understanding the robustness of the observed genotype–phenotype associations, the role of genotype-by-environment interaction (GEI) shaping fitness trade-offs and maintaining genetic variation of quantitative traits. However, the molecular basis of complex traits in vertebrates has rarely, if ever, been studied simultaneously in natural and controlled laboratory environments.
To evaluate whether the same genomic regions affect the growth of juvenile Atlantic salmon in wild and hatchery conditions, we mapped QTLs affecting the size-at-age of juvenile parr after the first summer utilizing the same mapping (family) material to avoid confounding effects of different genetic background.
We identified three significant QTLs for fork length in the hatchery that were undetectable in the natural environment, while two QTLs detected in the wild were not...