How Rare Is It To Have Two Different Colored Eyes?

If you've ever wondered how rare it is to have two different colored eyes, look no further. As it turns out, people with different colors in their irises have a condition known as heterochromia. According to Healthline, this is the result of a variation of melanin in the eyes, which is what determines eye and skin color. People with less melanin or pigment in their eyes have a lighter-colored iris, while those with more pigment have a darker one.

Not everyone with heterochromia will look the same, however. That's because there are three different types of heterochromia: complete, central, and segmental. Complete heterochromia is when someone has two completely different colored eyes, while central heterochromia is when the center of the iris is a different color from the rest. Segmental heterochromia, on the other hand, is when a segment or section of an iris (not just the center) is a different color compared to the rest of it. Central and segmental heterochromia can occur in both eyes.

Heterochromia is a rare condition

Regardless of the type, all heterochromia is extremely rare, according to All About Vision. In fact, complete heterochromia only affects six out of every 10,000 people. This means that less than 200,000 Americans have two different colored eyes. Fewer than 1% of people have any form of heterochromia, per Medical News Today.

Although most people who are born with heterochromia don't have any associated health conditions, it can sometimes be a symptom of an underlying congenital disease, according to Verywell Health. While rare, heterochromia can be caused by Horner's syndrome, Waardenburg syndrome, tuberous sclerosis, or Sturge-Weber syndrome.

If heterochromia develops later in life, it could be a sign of cancer or diabetes, or a result of surgery or trauma to the eye. To know the exact cause of your heterochromia, you'll need to be evaluated and diagnosed by an ophthalmologist. There's usually no need for treatment unless your heterochromia is the result of an injury or underlying disease.