Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2025
Erindi/veggspjald / Talk/poster V4
Höfundar / Authors: Paul Vincent Debes 1, Einar Svavarsson 1, Christos Palaiokostas 2
Starfsvettvangur / Affiliations: 1. Hólar University; 2. Swedish University of Agricultural Sciences
Kynnir / Presenter: Paul Vincent Debes
Iceland’s freshwater bodies harbour only few fish species that are assumed to have colonised the island after the last glacial period or - which is heavily disputed - may have remained in small glacial refugia. Mitochondrial DNA does not recombine, is maternally inherited, and is therefore ideal to trace maternal origin and reconstruct part of the population history. Until now, it was thought that Icelandic Arctic charr originated from one whole mitochondrial subclade shared with individuals from Norway and Greenland, named Atlantic subclade 2. Arctic charr belonging to a second clade, Atlantic subclade 1, had this far been only identified in western Greenland. The divergence time between subclades 1 and 2 has been estimated to be 41,000-75,000 years before present, falling within the last local glacial period. We assembled whole mitochondrial sequences from the Icelandic breeding programme and compared them with published whole mitochondrial sequences of known origin. Based on preliminary results and by tracing back current breeding programme samples to their maternal wild founders, we were able to assign individuals originating from landlocked lakes to Atlantic subclade 2 but individuals from anadromous river populations to Atlantic subclades 1 and 2. These results support a history of Icelandic Arctic charr from at least two glacial refugia. Future analyses of nuclear genomes across wild populations may provide further insights into their history.