Говорят, они с Поволжья, как и мы.

[pargentum]

Вот видите - раньше сардинийцы с корсиканцами владели Европой, а потом понаехали всякие там кельты с латинцами да германцы со славянами. И ничего.

Iceman's DNA reveals health risks and relations : Nature News & Comment:

Zink’s team also gathered information about Ötzi’s ancestry. His Y chromosome possesses mutations most commonly found among men from Sardinia and Corsica, and his nuclear genome puts his closest present-day relatives in the same area. Perhaps Ötzi’s kind once lived across Europe, before dying out or interbreeding with other groups everywhere except on those islands.

That makes sense, says Eske Willerslev, a palaeogenomicist at the University of Copenhagen. “Sardinians are a group that people have considered distinct from other Europeans, and in this regard it would be interesting if they were more widely distributed in the past.”