Studies carried out by scientists from the Institute of Forensic Genetics at the University of Copenhagen have concluded that all blue-eyed people share a common ancestor, someone who lived 6,000 to 10,000 years ago near the area by the Black sea.
Researchers analyzed and compared the unique genetic make-up of the chromosomes in the iris from 155 blue-eyed individuals from diverse regions such as Denmark, Turkey and Jordan.
All of the subjects that participated in the study had the exact same genetic "mutations" in specific chromosomes of the eye with very little variation on the genes, indicating that the "mutation" responsible for blue-eyes first arose and spread relatively recently. (Source: http://link.springer.com/article/10.1007%2Fs00439-007-0460-x )
Following the ending of the last Ice Age, many Europeans inherited this rare gene associated with blue-eyed people that differentiated them from the rest of the human races.
Indeed, it appears that the elite and nobility that organized the earliest known agricultural civilizations all shared this trait, seemingly coming from the same bloodline.
These blue eyed statues (pictured below) are of Sumerians from the early/mid 3rd millennium BC. ''...they (the Sumerians) certainly belong to the same racial division of mankind as the nations of Europe, they are scions of the Caucasian stock’’ - Arthur Keith (quoted in Ur Excavations, 1927)
Archeologists working at Peru's Huaca Pucllana ruins recently pulled a blue-eyed mummy from an ancient tomb thought to be from the ancient Wari culture that flourished before the Incas. Piercing blue eyes undimmed by the passing of 1,300 years, this is the "Lady of the Mask" – a mummy with striking blue eyes, whose discovery could reveal the secrets of a lost culture at the Huaca Pucllana Pyramid located in Lima, Peru. It is the first time a tomb from the region’s Wari culture has been discovered intact and gives historians the chance to learn about the ancient pre-Incan civilizations.
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 near the arctic circle - where blue eyes are still most prevalent.
These "mutations" are relatively recent as Europe was colonized only a few thousand years ago, say mainstream scientists. Through interbreeding, the brunette with blue eyes (Neanderthal-type) was evidenced about 35,000- 25,000 years ago by invading Cro magnon types from the Atlantic (Tall, RH negative blood type, Solutrean tool kit).
“The question really is, ‘Why did we go from having nobody on Earth (known) with blue eyes 10,000 years ago to having 20 or 40 percent of Europeans having blue eyes now?”
In contrast, most mammals on earth 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.)