Thousands of years ago in Europe, a baby was delivered with a harmless genetic mutation. That change resulted in blue eye color. The eyes appear blue not because of any blue pigmentation in the iris, but rather, because of a lack of the pigment, Melanin, in the iris as a result of the mutation. Eye color depends on the amount of Melanin in the iris of the eye, the degree of deficiency determines the shade. Melanin is also responsible for the color of the hair and skin.
Melanin is the only pigment present in the eye and is brown. All other colors derived from the mutation, are truly not pigments. They appear as these other colors as a result of the way light reflects into and out of the eyes. The melanin in the iris helps to protect against damage caused by UV rays from the sun. With a deficiency in melanin, blue eyes are subjected to higher risk from the sun’s UV rays damage. That explains why people with blue eyes are advised to employ cautionary measures to protect their eyes from such damaging exposures, like wearing sunglasses when out and about in the sun.
All 8-10% Blue-eyed people of the world have a single common ancestor who lived around the Black Sea, six to ten thousand years ago. They then populated areas of Western Europe and Scandinavia, particularly people in places like Finland, Estonia, Ireland. All blue-eyed people are, therefore, distant relatives as a result of inheriting a melanin-deficient mutated gene.