Let's talk about Eye Color & Genetics
Eye color is can be a striking feature, so it’s no surprise people write songs and poetry celebrating someone’s eye color. Whether or not you believe eyes are the window to the soul, eye color is a genetic trait that has interesting things to say about your DNA.
How it works
We get our eye color from a type of pigment called melanin. Melanin also determines the color of our skin and hair. People who have a lot of a black- or brown-colored type of melanin called eumelanin in the front layers of the iris will probably have darker eyes. Eumelanin is good at absorbing light, which gives it its darker color. People with blue eyes have much less of this pigment in their eyes.
The genetic link
Eye color is a complex genetic trait because multiple genes are involved. One of the most important genetic factors is a marker near a gene called OCA2 that affects how much brown pigment your cells produce, and thus how much brown pigment is in your eyes.
Did you know?
Our ancient ancestors had brown eyes. But at some point in history, a baby was born with a genetic variant leading to a new eye color: blue. Most light-eyed people carry that same genetic variant to this day.
What’s the genetic story behind your eye color? 23andMe’s Health + Ancestry Service can help you find out. Pick up one of our kits and we’ll tell you what your genetics have to say about your eye color.
Eiberg H et al. (2008). “Blue eye color in humans may be caused by a perfectly associated founder mutation in a regulatory element located within the HERC2 gene inhibiting OCA2 expression.” Hum Genet. 123(2):177-87.