Investigation Discovers Arctic Bear DNA Variations May Help Adaptation to Global Heating

Researchers have identified alterations in Arctic bear DNA that could enable the mammals adapt to increasingly warm climates. This study is considered to be the initial instance where a meaningful association has been identified between escalating temperatures and shifting DNA in a free-ranging mammal species.

Climate Breakdown Threatens Polar Bear Future

Environmental degradation is jeopardizing the existence of Arctic bears. Forecasts show that a large portion of them may vanish by 2050 as their icy environment retreats and the climate becomes hotter.

“Genetic material is the guidebook inside every biological unit, instructing how an organism develops and functions,” said the principal investigator, Dr. Alice Godden. “By examining these bears’ expressed genes to local temperature records, we observed that increasing heat appear to be driving a dramatic surge in the function of mobile genetic elements within the south-east Greenland polar bears’ DNA.”

DNA Study Shows Important Changes

Researchers examined biological samples taken from Arctic bears in two regions of Greenland and contrasted “transposable elements”: small, mobile sections of the genome that can alter how other genes function. The research examined these genes in relation to climate conditions and the associated changes in DNA function.

With environmental conditions and nutrition change due to alterations in habitat and food supply driven by warming, the DNA of the bears seem to be adjusting. The group of polar bears in the hottest part of the area displayed more changes than the communities farther north.

Likely Survival Mechanism

“This discovery is significant because it indicates, for the first time, that a unique group of polar bears in the warmest part of Greenland are employing ‘mobile genetic elements’ to quickly rewrite their own DNA, which may be a desperate coping method against retreating Arctic ice,” noted Godden.

Temperatures in the northern area are more frigid and less variable, while in the south-east there is a more temperate and ice-reduced environment, with significant temperature fluctuations.

Genomic information in animals mutate over time, but this evolution can be sped up by environmental stress such as a rapidly heating climate.

Nutritional Changes and Genetic Hotspots

The study noted some interesting DNA alterations, such as in regions connected to lipid metabolism, that could help polar bears survive when food is scarce. Animals in hotter areas had increased terrestrial diets compared with the lipid-rich, marine nutrition of Arctic bears, and the DNA of south-eastern bears appeared to be evolving to this new reality.

Godden elaborated: “We identified several genetic hotspots where these jumping genes were very dynamic, with some located in the critical areas of the genome, implying that the animals are undergoing swift, profound genetic changes as they adjust to their disappearing sea ice habitat.”

Future Research and Broader Impact

The next step will be to examine other Arctic bear groups, of which there are 20 around the world, to observe if analogous genetic shifts are happening to their DNA.

This investigation may assist protect the bears from disappearance. However, the researchers stressed that it was crucial to slow temperature rises from increasing by lowering the use of fossil fuels.

“Caution is still required, this provides some hope but is not a sign that polar bears are at any reduced threat of disappearance. It is imperative to be undertaking all measures we can to lower global carbon emissions and decelerate global warming,” stated Godden.