Parallel epigenetic modifications induced by hatchery rearing in a Pacific salmon

Abstract

Significance Captive rearing is known to impact the fitness of individuals released in the wild, but the relative role of genetic vs. nongenetic underlying processes is still debated. We measured genome-wide methylation profiles to document epigenetic differences between Pacific salmon originating from a hatchery and their natural-born congeners in two geographically distant rivers. Our results provide evidence that the epigenetic modifications induced by hatchery rearing provide a potential explanatory mechanism for reduced fitness of hatchery-reared salmon once released in the wild.