Eyes are not just windows to the soul—they're kaleidoscopes of human diversity. From deep brown to icy grey, eye colours span ...

Blue is not the rarest eye color In fact, it’s the second most common in the United States after brown eyes. According to the American Academy of Ophthalmology, about 27% of Americans have blue ...

Horses have beautiful blue or brown eyes, depending on their genetics. Breeds with white markings or light-colored coats, such as the Akhal Teke, are more likely to develop blue eyes.

In effect, the turned-down switch diluted brown eyes to blue. If the OCA2 gene had been completely shut down, our hair, eyes and skin would be melanin-less, a condition known as albinism.

The stroma in brown eyes contains high levels of brown-to-black melanin, so this is the color we see. For grey eyes, it’s a similar phenomenon to blue, except the stroma contains more collagen.