Heterochromia: The Science Behind Your Beautifully Mismatched Eyes

Sid S

Published on April 20, 2021, 11:11 am

Heterochromia: The Science Behind Your Beautifully Mismatched Eyes

In a world where people like to match everything from their outfits to shoes, a rare species is living with different coloured eyes. Sounds too bizarre right? Except it’s not! And they also have a name for it - Heterochromia.

In case you have a crush on Henry Cavil or Alice Eve and have looked at their photos several times, you may know about this condition already.

Heterochromia iridum is used to describe a condition where a person is either born with different eye colours or develops it later in life.

It is quite a rare condition that affects 6 in every 1000 people. Tbh, I think it is the sexiest condition (in a strange way). If you also have it, just know that your eyes are perfectly mismatched.

Although it is rare in humans, it’s more evident in animals such as cats, dogs and horses. Let’s know more about heterochromia eyes and what causes this pretty genetic mutation.

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What Determines Your Eye Colour?

Eye colour is one of the most distinctive physical traits that’s often mentioned in poems and songs. But, what decides the eye colour one is born with? Sure genetics has some doing, but there’s more than meets the eye.

Iris is the coloured tissue in front of the eye. It makes the pupil dilate or constrict to control the amount of light that enters it.

Melanin deposits in the iris are where your eyes get their colour from. Eyes with little melanin deposits are blue. Whereas, more melanin deposits make the eyes brown, hazel or green.

The eye colour doesn’t have to be the same forever. It may change as long as the melanin develops. For instance, a baby may be born with blue eyes that darken over 3 years as melanin production increases.

When someone’s eye appears to be multicoloured, they probably have heterochromia iridum.

Melanin is also present in your skin cells and hair which means that it also has to do something with your skin and hair colour. The deficiency of melanin leads to skin pigmentation disorders such as vitiligo.

Types of Heterochromia

Types of Heterochromia

There are mainly three variations of heterochromia- complete, central and sectoral. All these three types are triggered due to melanin deposits in the iris. But, all of them differ in appearance.

1. Complete Heterochromia

When the eyes appear different in colour, it’s known as complete heterochromia. For example, one may look blue and the other one brown. Every one in six Siberian huskies has central heterochromia eyes.

2. Central Heterochromia

It refers to the discolouration within the iris. The inner ring of the iris is different from the colour of the outer ring. The inner ring often seems to have flecks of different colours.

3. Sectoral Heterochromia

Also known as partial heterochromia, it occurs when only one part of the iris is different from the rest. You may as well take it as a spot on your iris.

Partial heterochromia can be dangerous as the tiny eye freckles can turn into cancerous melanoma over time. It’s best to see a specialist to cheek these eye freckles. If you are under 16 or 19 (in full-time education), you are eligible for NHS eye tests. If not, you may come to us and get a free eye test in the UK by our skilled opticians.

Did You Know?

We offer free eye exams at our stores in Manchester, even if you don't have an NHS Optical Voucher!

Check out the Specscart store locations where you can get a Free Eye Test.

When in doubt, you can come to us at Specscart, get a free eye test and get better clarity for your symptoms.

Heterochromia Causes

Heterochromia present at the time of birth is called genetic heterochromia. Research indicates that most cases of heterochromia eyes are benign and rarely occur due to an underlying abnormality.

Even if nobody in your family has this condition, you can still have it. However, some rare cases are associated with the following syndromes and diseases:

  • Bloch-Sulzberger syndrome
  • Hirschsprung disease
  • Parry-Romberg syndrome
  • Von Recklinghausen disease
  • Bourneville disease
  • Horner’s syndrome
  • Sturge-Weber syndrome
  • Waardenburg syndrome

When a person develops heterochromia later in life, it’s known as acquired heterochromia. In this case, heterochromia’s causes may include:

How to Identify Heterochromia?

Identify Heterochromia

Heterochromia iridum is easy to identify. If your eyes are differently coloured or you spot colour differences within the same eye, you most probably have this condition. However, the difference can be minor which is only visible under specific lighting conditions or photographs.

This unusual genetic mutation has no other symptom. But if it happens due to an eye injury or trauma, it is presented with other signs and symptoms.

Your optometrist may also diagnose this during your annual eye care exam. If you’ve recently acquired this condition or your genetic heterochromia has changed, you must see an optician.

You are also welcome to get a free comprehensive eye exam from our Opticians in Walkden and Opticians in Bury. They are friendly blokes with loads of experience.

Is Heterochromia Bad?

Heterochromia doesn’t affect your visual performance unless it is linked to any medical condition. However, you must have an eye test to rule out all the possibilities.

If no other health issues are present, you don’t need treatment for heterochromia. I might sound a bit cheesy here but “what sets you apart is what makes you great”. Do not grumble about why you aren’t like everybody else. Rather, embrace your uniqueness and turn it in your favour. That’s my best advice to you. I mean Mila Kunis has this condition and in my opinion, she is one of the prettiest women in the world.

While I suggest you leave your genetic heterochromia as it is, for any other vision problem, you can buy prescription designer glasses online from us at affordable prices.

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