Brown and hazel eyes get their color from melanin, the same pigment that colors your skin. The more melanin in the eye, the darker your eye color will appear. But blue eyes don't have any blue ...

The MC1R (or melanocortin 1 receptor) gene helps decide your hair, skin and eye coloring ... compared with 45% who have brown eyes and 27% who have blue eyes. But it’s not quite that simple.