How Do You Get The Color Of Your Eyes?

It is said that “eyes are the window to the soul”. In reality, in some parts of the world, people don’t allow themselves to be photographed, fearing that their souls would be taken away by having their picture snapped. That might sound like a bit of a crazy idea, but  have you ever wondered about another interesting aspect of our eyes? Perhaps the most notable aspect of them, in fact. How did you get your eye color?

Well, much of that depends on your parents, as the color of your eyes depend on the genes you received from your mother and father. However, it is not that simple, as a child can also have a completely different eye color than both of its parents.

What Determines Eye Color?

Each person is born with 46 distinct chromosomes that are divided into 23 pairs. Each parent provides one chromosome to make a pair. Chromosomes are comprised of DNA called genes. Genes contain a segment called “alleles”, which determine the color of your eyes. Scientist believe that about 16 different genes play a role in determining eye color, which is the reason why there are so many different eye colors out there in the world.

Human Eye

Credits:Piotr Krzeslak/Shutterstock

There are two different types of alleles: dominant and recessive. If two alleles, coming from each parent, are the same, then they are called homozygous. This will result in the child having the same characteristics of eyes as those of the parents. If two alleles are of different types, then they are called heterozygous. In this case, the dominant alleles will determine the color of the eye, while the recessive alleles will remain unexpressed.

genetics1

Brown (B) is more dominant then Blue (b)

Brown alleles are dominant over both green and blue, whereas green alleles are dominant over blue alleles. This is the reason why the most common eye color is brown. A person having both recessive and dominant alleles will have the dominant eye color, but that person is still able to retain the recessive alleles genes, which can be passed on to future generations. This is the reason why brown-eyed parents occasionally end up with a blue-eyed child.

Genes also determine your eye color by determining how much melanin is produced in your iris. Melanin is a pigment that is found in your skin and eyes. It is this melanin that determines which alleles are dominant in your eyes.

Different Eye Colors

Different Eye Colors (Credits:Ihor Voloshyn/Shutterstock)

The iris of your eye contains two different layers: the back layer and front layer. The back of the iris is usually blue, but the melanin produced in the front layer determines your eye color. The greater the amount of melanin produced, the darker the eye color. Brown eyes have the most melanin, whereas green eyes have less and blue eyes have no melanin in the front layer of the iris at all. Melanin production does not begin at birth, which is the reason why most babies’ eyes appear blue.

More about Eye Color

All people with blue eyes came from the same ancestors!

Albino Eyes

Albino Eyes (Credits:Natalia_R/Shutterstock)

Albino eyes have no melanin in either the front or back layer, so their eyes appear red or pink because of their blood vessels.

Heterocromia eyes

Heterocromia eyes (Credits:pio3/Shutterstock)

Some people also have two different eye colors; this phenomenon is called heterochromia, which is due to either an excess or lack of pigment within an iris or part of an iris.

References:

  1. The Genetics Of Eye Color Inheritance – Go Ask Alice! (Columbia University)
  2. All About Vision
The short URL of the present article is: http://sciabc.us/T1pEQ
Help us make this article better
About the Author:

Ashwin Vinod has a B.Tech in Electronics and Communications from APJ Abdul Kalam Technological University, Trivandrum (India). He likes to watch movies, reading fiction novels and surf the internet.

.
Science ABC YouTube Videos

  1. Why Is Space Cold If There Are So Many Stars?
  2. Why Do You Hear A Rumbling Sound When You Close Your Eyes Too Hard?
  3. Hawking Radiation Explained: What Exactly Was Stephen Hawking Famous For?
  4. Current Vs Voltage: How Much Current Can Kill You?
  5. Coefficient Of Restitution: Why Certain Objects Are More Bouncy Than Others?
  6. Jump From Space: What Happens If You Do A Space Jump?
  7. Does Earth Come To The Same Spot Every Year On Your Birthday?
  8. Bird Strike: What Happens When A Bird Strikes An Aircraft?

Tags:

Get more stuff like this
in your inbox

Subscribe to our mailing list and get interesting stuff and updates to your email inbox.