If you’ve got blue eyes, shake the hand of the nearest person who shares your azure irises: He or she may be a distant cousin.

Danish researchers have concluded that all blue-eyed people share a common ancestor, presumably someone who lived 6,000 to 10,000 years ago.

“Originally, we all had brown eyes,” Professor Hans Eiberg of the University of Copenhagen said in a press release. “But a genetic mutation affecting the OCA2 gene in our chromosomes resulted in the creation of a ’switch,’ which literally ‘turned off’ the ability to produce brown eyes.”

That “switch” — a simple change from “A,” or adenine, to “G,” or guanine, in the DNA — actually sits next to the OCA2 gene, which regulates the pigmentation of our eyes, hair and skin, and hence has only a limiting effect on it.

If the mutation had completely deactivated OCA2, all blue-eyed people would be albinos.

Eiberg and his team analyzed 155 individuals in a large Danish family, plus several blue-eyed people born in Turkey and Jordan. – FOX NEWS