Shared genomic signatures of Arctic adaptation among distantly related plant lineages

Across four Arctic plant species, 214 orthogroups show signatures of positive selection in all Arctic lineages, about 1.6× the number shared among non-Arctic relatives.

• Why it matters: Arctic survival involves extreme, seasonally shifting stresses, but it is unclear whether these conditions leave shared genomic signatures across deeply diverged plant lineages.
• What they did: The study built a chromosome-level genome assembly for Oxyria digyna and compared it with reference genomes for Cochlearia groenlandica, Draba nivalis, and Dryas octopetala, plus 16 non-Arctic species from the same families.
• The result: Arctic genomes showed shared positively selected genes, copy-number variation linked to biotic interactions, sexual reproduction, and nutrient acquisition, and lower proportions of some repetitive elements, including terminal inverted repeats.