Green Eyes Appear in Only 2% of Humans as Rare Genetic Mix Limits Their Spread

1 articles · Updated · Forbes · May 13

Only about 2% of humans have green eyes because they require an unusually narrow biological combination—intermediate melanin, lipochrome in the iris and Rayleigh light scattering rather than any green pigment.
Two genes on chromosome 15, OCA2 and HERC2, drive most eye-color variation, and a single HERC2 variant identified in 2008 largely predicts whether eyes are brown or blue, making green a harder outcome to produce.
Ancient DNA suggests light eyes are evolutionarily recent: most Europeans still had dark eyes, hair and skin as recently as 3,000 years ago, despite today’s association of green and blue eyes with Europe.
Researchers say strong selection favored lighter eyes in prehistoric Europe, but still debate whether the advantage came from better low-light adaptation, mate preference for rare traits, or both.

Why is the world's rarest eye color not a real color, but a complex genetic illusion?

Did an ancient survival advantage make light-eyed people more vulnerable to modern screen damage?