I got google-y for fun and every scientific paper title implies its inuit greenlanders whom have the mutation, not the euro greenlanders, and greenland is about 90% inuit. The picture of the prof looks like he's a euro greenlander looks like Denmark heritage to me but who knows (and it doesn't matter much anyway).
wikipedia says the inuit greenlanders have been chillin on the island for near 5000 years now.
I would imagine due to intermarriage, if the euro greenlanders are outnumbered 10 to 1, that quite a few euro greenlanders have the mutation, but the paper titles all seem to imply inuit greenlanders only.
The wikipedia article implies the archeological inuit greenlander diet was mostly carnivore. That's actually pretty healthy as long as they eat enough organ meats but not too much (particularly liver)