Whole Genome Sequencing Provides Astonishing Details About the Greenland Halibut

After conducting a whole-genome sequence on the Greenland Halibut, researchers expressed that the fish appear to be panmictic in most of the Northwest Atlantic. Moreover, their work enables further studies of genomic datasets to characterize the effects of climate change across different species.

The long-term presence of the Greenland Halibut in the Northwest Atlantic requires accurate information about its geographic population structure and local adaptation for scientists to understand more about the species. Using 1,297 Greenland Halibut samples from 32 locations in the said area, scientists were able to generate high-quality whole-genome sequencing data that provided an outlook of the fish's population difference among areas, environmental survival, phenotypic differences, and levels of migration.

In terms of population genetic structure, scientists found an absence of population differentiation between Canada and West Greenland, but significant genetic differentiation between the Gulf of Saint Lawrence and the remainder of the Norwest Atlantic. Thus, the fish seem to appear panmictic, or randomly mates within a breeding population, throughout the region except for the Gulf of Saint Lawrence. On the other hand, environment association analyses show that divergence between two Greenland Halibut stocks results mainly from environmental variables like sea temperature and dissolved oxygen. Phenotypic differences between halibuts from the Gulf of Saint Lawrence and Northwest Atlantic were also observed to have likely resulted from functional adaptive divergence to their environmental conditions. Lastly, assessment of the high levels of migration between the two stocks found that the Greenland Halibut may potentially escape unfavorable environmental conditions in the Gulf of Saint Lawrence.

The full study was published by Frontiers in Marine Science.