Environment-driven reprogramming of gamete DNA methylation occurs during maturation and influences offspring fitness in salmon

We investigated whether exposure to a captive environment during maturation influenced gamete DNA methylation for wild Atlantic Salmon individuals. We then investigated whether these parental effects were detectable in an F1 generation reared in a common environment. We associated DNA methylation with growth and fitness-related phenotypes and demonstrated that intergenerational effects of hatchery exposure during maturation of the parental generation influence fitness-related methylation patterns in the F1 generation. We compared DNA methylation of sperm for 6 wild males and 6 males that had been reared in captivity during maturation (SAS). Pure-type crosses of wild and SAS fish were created and we compared DNA methylation in liver tissue of F1 offspring (approximately 10 month old juveniles). For juvenile comparisons we used two offspring from each of four families for both wild and SAS groups (N total = 16).