The researchers discovered hibernator-specific DNA regions that regulate the FTO locus, tuning nearby genes up or down, likely to support rapid weight gain before hibernation, followed by long periods of fasting.

To test their theory, they edited these hibernator-specific DNA regions in mice (which don’t naturally hibernate). The result: changes in metabolism and behavior resembling that of hibernators, including altered weight regulation, body temperature control, and foraging instincts.

“When you knock out one of these elements — this one tiny, seemingly insignificant DNA region — the activity of hundreds of genes changes,” said co-author Susan Steinwand in the press statement. “It’s pretty amazing"