Only about 2% of people in the world have naturally green eyes
. Green eyes are a genetic mutation that results in low levels of melanin, though more melanin than in blue eyes
. The highest concentration of people with green eyes is found in Ireland, Scotland, and northern Europe
. Around 8–10% of men and 18–21% of women in Iceland and 6% of men and 17% of women in the Netherlands have green eyes
. Green eyes are caused by the combination of an amber or light brown pigmentation in the stroma of the iris and a blue shade created by the Rayleigh scattering of reflected light
. Green eyes contain the yellowish pigment lipochrome
