The Arctic Ocean is a remote and inaccessible ocean basin for most of the year. Thus, it is extra valuable to attain new information from previously collected material. When analyzing DNA in archived cores, a considerable problem is the risk for contamination by modern environmental DNA. This research project will explore archived sedimentary cores collected from previous expeditions to the Arctic Ocean using molecular genetic techniques. The aim is to find novel proxies providing palaeoenvironmental information that are insensitive to the presence of contaminants. The project will investigate the preservation of sedaDNA in central Arctic Ocean sediments, with a particular focus on the coccolithophore Gephyrocapsa huxleyi (formerly Emiliania huxleyi). This is one of the most important datums in Arctic paleoceanography, and is routinely used to identify the last interglacial period. However, carbonate preservation in Arctic sediments is often very poor, with sporadic occurrences downcore, and in many instances calcareous nannofossils are completely absent from quaternary sediments. Furthermore, poor preservation of the nannofossils has caused confusion in the correct taxonomic identification. The aim is to explore the use of sedaDNA to overcome the limitations of carbonate preservation in biostratigraphic analyses, and ultimately help to more confidently place the first occurrence datum of G. Huxleyi in the stratigraphic framework of Quaternary Arctic Ocean sediments. In this project, we aim to analyze genomic data produced from 100 sediment sample staken from several deep sea cores. Using a shotgun approach, all DNA will be sequenced and mapped to a selected reference genome of G. huxleyi in order to identify the presence/absence of this taxa throughout two sediment cores. Robust bioinformatic tools will be used to distinguish between ancient genetic signals and modern contaminants. The proposed project will further produce rich material for reuse by geneticists and by the geological communities and thereby significantly contribute to the field.