One genuinely distinctive quality about you is the color of your eyes. Your eyes are the only ones on the planet that are exactly the same color. Although eye color has inspired poems, paintings, and photographs, scientists have discovered that eye color can sometimes reveal far more about a person. We’ll explore the variation of eye colors, their prevalence, development, genetic factors, and associated health conditions.
Table of Contents
Different Types of Eye Colors
Eye color is determined by the pigmentation of the iris, a structure surrounding the pupil that controls light entry. The iris color ranges from light blue to dark brown, with blue, green/hazel, or brown being the most common, with brown being the most common worldwide eye color.
| Brown: 80%
The most common eye color globally, particularly in Asia and Africa. |
Blue: 10%
Less common but more prevalent in European populations. |
Green: 2%
Rarest eye color, found in approximately 2% of the world’s population. |
Hazel: 5%
A varied mixture of brown, green, and amber hues. |
Gray: 3%
Rare and often considered a variation of blue or green eyes. |
Amber: Unknown
They are extremely rare, but their prevalence is unknown. |
How Eye Color Develops
The distribution and quantity of the brown pigment known as melanin in your iris determine the color of your eyes. Put simply, blue eyes lack pigment, whereas brown eyes do. Additionally, the hues of the eyes in between differ greatly. Even if a family member and you have similar eye colors, each person has a different amount and distribution of melanin in their iris.
The majority of newborns have blue eyes, which could darken in the first three years if melanin forms. It is more probable that the children of brown-eyed parents will also have brown eyes. Green frequently defeats blue, and brown typically triumphs over green due to the dominance of darker eye colors. That being said, a child born to a parent who has brown eyes and another who has blue eyes will not necessarily have brown eyes. 
- Brown: 70-79%
- Blue: 8-10%
- Hazel: 5%
- Gray: 3%
- Green 2%
- Red or violet: less than 1%
- Heterochromia (partly or completely different-colored eyes): 1%
Genetics of Eye Color
Eye color is determined by variations in a person’s genes. Most of the genes associated with eye color are involved in the production, transport, or storage of a pigment called melanin. Eye color is directly related to the amount of melanin in the front layers of the iris. People with brown eyes have a large amount of melanin in the iris, while people with blue eyes have much less of this pigment.
Up to 16 genes have been linked to the inherited color of the eyes. OCA2 and HERC2 are a couple of the genes linked to eye color. It has been established that the previous notion—that blue eyes are a straightforward recessive characteristic—is untrue.
Your eyes will probably have a similar hue to your biological parents’ since you inherited their DNA. However, even if both of your parents have blue eyes, it’s still possible for you to have brown eyes. Due to the complexity of eye color genetics, nearly any parent-child combination of eye color can exist. Mutations in genes can also create rare eye color variations such as red, violet, or heterochromia.
Conditions Affected by Eye Colors
Eye color can change due to medications or medical conditions, with some changes being harmless and others potentially serious, like Macular degeneration. Examples include:
Cataracts: cloudy areas in the eye’s lens, affecting light focusing, and are prevalent as individuals age.
Glaucoma: a group of eye diseases that cause vision loss and blindness by damaging the optic nerve in the back of the eye. Symptoms can start slowly, and a comprehensive dilated eye exam is the only way to detect them.
Horner syndrome: a condition resulting from a medical event like a stroke, tumor, or spinal cord injury, causing a disrupted nerve pathway from the brain to the face and eye.
Macular degeneration: the macula of the eye, responsible for central vision, breaks down, causing vision loss in reading and driving activities. While peripheral vision remains intact, total blindness is not typically experienced, making these activities difficult for most individuals.
Ocular albinism: causes light-colored eyes and vision problems due to reduced iris pigmentation.
Oculocutaneous albinism: affects skin and hair pigmentation, resulting in light-colored irises, fair skin, and white or light-colored hair.
Heterochromia: different-colored eyes in the same individual, either due to genetic changes, eye development problems, or eye disease or injury.
Eye color can also be linked to certain diseases, with brown eyes having a higher risk of cataracts and blue eyes being more resistant to mental health conditions. If you notice sudden or sudden changes in eye color, it’s recommended to consult an eye care specialist for further attention and care.
Heterochromia: The Phenomenon of Different Colored Eyes
Heterochromia is a rare condition characterized by mismatched eye colors, most often brown and blue. It can be due to genetic changes, eye development problems, or eye disease or injury. Although it can occasionally indicate underlying medical issues, it is usually benign and doesn’t need to be treated unless further complications are found.
There are 3 types of heterochromia:
- Complete heterochromia: two different colored eyes
- Sectoral heterochromia: Same color eyes, but one looks darker
- Central heterochromia: 2 different colors in the same iris. The outer ring is one color while the inner is another, and it may appear to have different color “spikes” from the pupil.
Famous people who have a form of heterochromia include:
Kate Bosworth
Benedict Cumberbatch
Robert Downey, Jr.
Joe Pesci
Angelina Jolie
Demi Moore
Christopher Walken
Simon Pegg
Olivia Wilde
Dan Akroyd
Keifer Sutherland
Jane Seymour
Max Scherzer
Elizabeth Berkley
Bill Pullman
Henry Cavill
Michael Flatley
Alyson Hannigan
When to See a Doctor About Your Eye Color
If, at any point, you experience or identify any of the following symptoms or indicators, you should contact a professional eye doctor for a medical examination:
- Sudden changes in eye color
- Unexplained eye color abnormalities or discoloration
- The presence of vision problems or eye discomfort associated with eye color changes
Schedule An Eye Examination Today
For inquiries, an appointment, or a personalized assessment, get in touch with the eye experts at Cleveland Eye Clinic.
