UCSB Science Line
Sponge Spicules Nerve Cells Galaxy Abalone Shell Nickel Succinate X-ray Lens Lupine
UCSB Science Line
How it Works
Ask a Question
Search Topics
Our Scientists
Science Links
Contact Information
I'm really confused... when I was born I had black eyes. After a few months they started to turn in chocolate brown. As time passed by they turned in clear blue color. And now that I am 14 they're changing again but this time into green. I just want to know what is happening to me. I'll appreciate so much if you guys would give me an answer. Thank you.
Question Date: 2014-03-27
Answer 1:

You have some unusual pigment-producing tissue in your eyes. I doubt very much that it is anything you need to worry about.

You (like everybody else) have a pigment in the back of your iris that is blue and colors your eyes blue. Most people - those with the dominant allele for eye color (dominant as defined in Gregor Mendel's laws of genetics; it has nothing to do with superiority) - have another pigment, which is brown, in the front of their irises, and this brown pigment masks the blue pigment behind it, causing most people's eyes to be brown.

From the sound of it, the brown pigment-producing tissues in your irises have been producing pigment unevenly throughout your life. When you were a baby, they produced so much of the brown pigment that your eyes were black, but over time, they stopped producing pigment, allowing your eyes to fade to blue. Now it sounds like they're picking up again, giving you the green color (blue + yellow/brown makes a green color). I am to understand that this is actually fairly common among people who have green eyes: their eyes don't stay green all of the time, or the shade of green shifts, etc. I know a woman myself who had green eyes when I met her but now is closer to brown.

What is causing you to be different from most people who have the same eye color all their lives? I don't know that directly, but from the sound of it I would guess that the gene that makes the brown pigment is getting turned on or off by some kind of biochemistry inside of your body. These changes are most likely driven by your aging. Exactly what and how, though, I haven't a clue. I just know that you are a long way from being alone.

I doubt very much that it has anything to do (good or bad) with the rest of your health, or with your ability to see.

Answer 2:

That's a great question. It is relatively rare for people's eye color to noticeably change as they age. Eye color is determined by the pigment melanin. The more melanin you have in the connective tissue at the front of the iris - the darker your eyes. People who have less melanin will have lighter eyes. If the melanin concentrations in your eyes are decreasing, your eyes will lighten, while if it increases, they will darken. Because substantial change in eye color can be related to certain health conditions, it is good to mention this to your eye doctor when you go for a check up.

Answer 3:

Most of the time when a baby is born, his or her eye color is blue because melanin, the pigment protein that colors skin, hair, and eyes, isn't in large abundance in the irises. The iris of the eyes controls how much light enters and exists the eye. You inherit you eye color from your parents and the amount of melanin you have is coded into your genome. When there is a lot of melanin, eyes are darkly colored (brown), but when there is not a lot of melanin, eyes are lightly colored (gray, hazel, blue). The amount of melanin usually stays the same in a person throughout their life, and people have the same eye color they had as an infant. In some cases, the eyes can keep changing color (melanin deposits are increased and decreased) due to environmental factors, injuries, or simply because of genetics.

Click Here to return to the search form.

University of California, Santa Barbara Materials Research Laboratory National Science Foundation
This program is co-sponsored by the National Science Foundation and UCSB School-University Partnerships
Copyright © 2020 The Regents of the University of California,
All Rights Reserved.
UCSB Terms of Use