Sharks and rays are common by-catch species in many NE Atlantic fisheries and recent declines in catches have led to restrictive measures by EU. However, understanding of stock structure and species dynamics to adequate fisheries management is still incomplete. E-IMMUNO proposes to use genes associated with adaptive immunity as candidate genetic markers to improve the spatial resolution of the genetic population structure of exploited NE Atlantic elasmobranchs. Immunity genes are under strong selective pressure by local pathogen communities, and often show stronger among population genetic differentiation than traditional neutral markers. E-IMMUNO will also allow inferences on the scale at which among-population differentiation occurs in elasmobranchs to guide initial management and conservation actions in these data deficient taxa. Transcriptomics of immunity-relevant tissues will complement the above data to improve understanding of the evolution of adaptive immunity.