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17 Diverse eye color

Genetics and Eye Color
Eye color is primarily determined by genetics,
involving multiple genes that control the
amount and type of pigments (melanin) in the
iris. The most significant genes include OCA2
and HERC2.

Blue Eyes and Melanin

1 Blue eyes have very little melanin in the iris.
The blue color is due to the scattering of light
by the structural composition of the eye, not
pigment.

Green Eyes and Unique Pigmentation

2 Green eyes are the rarest eye color, occurring due
to a combination of low melanin and a yellowish
pigment called lipochrome. The green appearance
is also influenced by light scattering.

Brown Eyes and Melanin
3 Brown eyes have the highest concentration of
melanin, which absorbs more light and appears
darker. This high melanin content offers better
protection against UV light and is more common
worldwide.

Heterochromia

4 Heterochromia is a condition where a person
has two different colored eyes or two different
colors within the same eye. It can be congenital
or acquired due to injury or disease.

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