Although it does not discuss Inuit specifically, the excellent book: _Power, Sex, Suicide: Mitochondria and the Meaning of Life_ [1] by Nick Lane discussed how

Although it does not discuss Inuit specifically, the excellent book: _Power, Sex, Suicide: Mitochondria and the Meaning of Life_ [1] by Nick Lane discussed how mitochondria can be "geared" to lean one way or another when dealing with additional energy inputs. Which is to say, different mitochondrial DNA either leans toward generating additional heat or generating additional ATP (and, eventually, fat) when presented with surplus energy inputs. It appears the difference is subtle but you would expect it to manifest itself across very broad population surveys. On the other hand, if everyone is getting tremendous energy input surpluses it probably doesn't matter. [1] https://www.goodreads.com/book/show/39001.Power_Sex_Suicide https://www.goodreads.com/book/show/39001.Power_Sex_Suicide