We are Family............

Saw this on Foxnews.com this morning. I happen to love my blue eyes, but this does creep me out just a bit. Although, in a sense, aren't we ALL related somehow or another!!??

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 the first man or woman to sport what must have seemed oddly colored peepers 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. 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. All blue-eyed subjects had the mutation, and among those was very little variation on the genes neighboring it on the chromosome, indicating that the mutation first arose relatively recently.

In contrast, most mammals share the "normal" form of the gene. The six-letter sequence is exactly the same among mice, horses, cows, rats, dogs, cats, monkeys, chimpanzees and humans with brown eyes. (No word on what gives Siberian huskies and Siamese cats blue eyes.) Eiberg figures the mutation took place on the northern of the Black Sea, but that's an educated guess, assuming the first blue-eyed human was one of the proto-Indo-Europeans who subsequently spread agriculture into western Europe and even later rode horses into Iran and India.

He also stresses that the switch, as the press release puts it, is "neither a positive nor a negative mutation." That's a bit disingenuous, as the mutation also produces greater instance of blond hair (sexually selected for even today) and fair skin, which confers a survival advantage by stimulating greater production of vitamin D in sun-starved northern European countries—exactly where blue eyes are still most prevalent.

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