biostudies-literatureEriksen EFEC | EU Framework Programme for Research and Innovation H2020 | H2020 Priority Excellent Science | H2020 Marie Skłodowska-Curie Actions (H2020 Excellent Science - Marie Skłodowska-Curie Actions)United States Department of Commerce | NOAA | National Marine Fisheries Service, National Oceanic and Atmospheric Administration (NOAA Fisheries)175-185https://www.ebi.ac.uk/biostudies/studies/S-EPMC11977281biostudies-literatureUnknown134(3-4)Mitonuclear discordance between species is readily documented in marine fishes. Such discordance may either be the result of past natural phenomena or the result of recent introgression from previously seperated species after shifts in their spatial distributions. Using ancient DNA spanning five millennia, we here investigate the long-term presence of Pacific bluefin tuna (Thunnus orientalis) and albacore (Thunnus alalunga) -like mitochondrial (MT) genomes in Atlantic bluefin tuna (Thunnus thynnus), a species with extensive exploitation history and observed shifts in abundance and age structure. Comparing ancient (n = 130) and modern (n = 78) Atlantic bluefin MT genomes from most of its range, we detect no significant spatial or temporal population structure, which implies ongoing gene floHeredityFive millennia of mitonuclear discordance in Atlantic bluefin tuna identified using ancient DNA.PMC11977281951649NA20OAR4320472813383Nielsen SVPiattoni FStar BAndrews AJKersten OFerrari GTinti FPersson POnar VAniceti VWiech MEriksen EFCariani AFontani FPiques GAtmore LMCilli EFerter KMalca EfalseFive millennia of mitonuclear discordance in Atlantic bluefin tuna identified using ancient DNA.Mitonuclear discordance between species is readily documented in marine fishes. Such discordance may either be the result of past natural phenomena or the result of recent introgression from previously seperated species after shifts in their spatial distributions. Using ancient DNA spanning five millennia, we here investigate the long-term presence of Pacific bluefin tuna (Thunnus orientalis) and albacore (Thunnus alalunga) -like mitochondrial (MT) genomes in Atlantic bluefin tuna (Thunnus thynnus), a species with extensive exploitation history and observed shifts in abundance and age structure. Comparing ancient (n = 130) and modern (n = 78) Atlantic bluefin MT genomes from most of its range, we detect no significant spatial or temporal population structure, which implies ongoing gene flo2025-01-01T00:00:00Z2025 Apr2026-06-03T04:54:54.773Z2025-07-05T03:04:45.576ZS-EPMC119772813992025810.1038/s41437-025-00745-1