There is increasing awareness that anthropogenic stressors, including global warming and harvesting, impact the complex ecosystem dynamics of the Arctic Ocean. How a species responds to these stressors, however, will rely on its genomic architecture(s) and adaptive capacity. Here, we report on the genomic composition and diversity of the keystone fish species polar cod (Boreogadus saida), across parts of its distributional range. Preliminary analyses of whole genome sequencing data across the northern Barents Sea and adjacent regions including Icelandic and Russian waters, uncover high geneflow and little population structuring. Interestingly, despite genomic intermixing, we identify several chromosomal inversions and fusions, displaying high degree of genetic divergence and strong signals of selection, and thus, indicative of signals of local adaptation. Additionally, we discover a large sex determining region on chromosome 5, harbouring the gene FOXJ3 involved in male gonad development. Our results provide new and valuable insights into the genomic architecture(s) and diversity of an ecological important species in a rapidly changing environment. The discovery of multiple chromosomal inversions as well as chromosomal fusions, demonstrates their importance for facilitating local adaptation under extreme environmental conditions, in an otherwise panmictic population with high gene flow.

Primary Presenter: Siv Nam Khang Hoff, University of Oslo (s.n.k.hoff@ibv.uio.no)

Authors:

Siv Hoff, Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Norway  (s.n.k.hoff@ibv.uio.no)

Marius Maurstad, Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Norway  ()

Alan Le Moan, Department of Marine Sciences-Tjärnö, University of Gothenburg, Gothenburg, Sweden  ()

Mark Ravinet, Faculty of Medicine & Health Sciences, University of Nottingham, UK  ()

Joël Durant, Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Norway  ()

Ole Kristian Tørresen,  Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Norway  ()

Ireen Vieweg, Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, UiT the Arctic University of Norway, Tromsø, Norway  ()

Jasmine Nahrgang, Department of Arctic and Marine Biology, Faculty of Biosciences, Fisheries and Economics, UiT the Arctic University of Norway, Tromsø, Norway  ()

Christophe Pampoulie, Marine and Freshwater Research Institute, Fornubúðir, Hanafjörður, Iceland  ()

Haakon Hop, Norwegian Polar Institute, Fram Centre, Tromsø, Norway  ()

France Collard, Norwegian Polar Institute, Fram Centre, Tromsø, Norway  ()

Jane Aanestad Godiksen, Demersal Fish Research Group, Institute of Marine Research, Bergen, Norway  ()

Ian Bradbury, Fisheries and Oceans Canada, Northwest Atlantic Fisheries Centre, St. John’s, Newfoundland, Canada  ()

Leif Christian Stige, Norwegian Veterinary Institute, Ås, Norway  ()

Paul Renaud, Akvaplan-niva, Fram Centre – High North Research Centre for Climate and the Environment, Tromsø, Norway and University Centre in Svalbard, Longyearbyen, Norway  ()

Kjetill Jakobsen, Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Norway  ()

Kim Præbel, Norwegian College of Fishery Science, Faculty of Biosciences, Fisheries and Economics, UiT The Arctic University of Norway, Tromsø, Norway  ()

Sissel Jentoft, Centre for Ecological and Evolutionary Synthesis, Department of Biosciences, University of Oslo, Norway  ()