Have you heard of heterochromia or odd eyes? This rare condition causes a person to have different coloured eyes, like Kate Bosworth, Mila Kunis or Jane Seymour.

What is heterochromia?

This medical term refers to the difference in colour between the iris of the two eyes (heterochromia iridis) or between parts of the same iris (heterochromia iridum).

There are three types:

  • Complete heterochromia is simply two different coloured eyes.
  • Central heterochromia is when there are two different colours in one eye, the outer ring of the eye is one colour and the inner ring is another colour.
  • Sectoral heterochromia is recognized when a portion of the iris is a different colour from the rest. This is generally an irregular spot on the iris.

Causes of heterochromia

This rare condition is caused by a variance in the concentration and distribution of melanin in the iris of the eye. The iris is responsible to contract or dilate to let light into the pupil, it is the coloured portion of the eye. Its colour comes from melanin which is our body’s natural pigments that provide colour to our skin, hair and eyes. When the melanin is not distributed evenly, the result is two different coloured eyes or a partial colour difference in one eye.

Typically, people are born with it and it is not considered a medical condition nor does it affect vision. However, if the condition develops later in life, called acquired heterochromia, it would be important to consult with your eye doctor because it may be a sign of an underlying health issue. Acquired heterochromia is rather rare, it may be caused by:

Heterochromia is not reversible but if you would prefer to have the same colour eyes, speak with your optometrist about coloured contact lenses. 

Our irises are as unique as our fingerprints and having two different colour irises is much more uncommon. Only 6 out of 1,000 people have this condition. Are you one of those? Tag us on Facebook or Instagram to show us your eye colours!