Tibetans born to live the high life, study finds

Tibetans are able to live at high altitude thanks to a special gene they inherited from a mysterious, now-extinct branch of the human family, scientists reported on Wednesday.

The ancestors of today's Tibetan ethnic group acquired a key variant of a gene regulating oxygen in the blood when they mated with a species of human called the Denisovans, they said.

Contemporaries of the Neanderthals - and like them, possibly wiped out by anatomically modern man, Homo sapiens - the Denisovans first came to light only four years ago.