Have you ever wondered why cats can have different coloured eyes? Find out what causes it here.
There’s no doubt that cats’ eyes are beautiful. Many moggies will happily show them off by staring at you as you eat your dinner. But did you know that some cats have more striking eyes than others?
Although it’s quite rare, a condition called heterochromia can result in cats having two different coloured eyes. These odd-eyed cats typically have one iris (the coloured part of the eye) that’s blue. The other is either green, brown or yellow. Heterochromia can also affect dogs and even humans too.
What causes heterochromia in cats?
All kittens are born with eyes that appear blue due to a lack of pigment within the iris. Within their first few weeks/months of life a pigment called melanin is distributed throughout the iris. This causes the eyes to change colour. Usually this happens in both eyes, but if the cat has heterochromia, melanin is only distributed in one iris. This leaves the other iris blue.
It isn’t clear what causes some cats to develop heterochromia and others not. It appears to be a developmental condition. While there could be a genetic link, nobody knows what causes this strange and beautiful phenomenon. Some breeds of cat seem more likely to develop heterochromia than others. But it can happen to any cat.
Do odd-eyed cats have poor eyesight?
Luckily, heterochromia doesn’t have any impact on a cat’s ability to see. It doesn’t seem to affect their hearing either. White cats with one or two blue eyes are more likely to be deaf. But non-white cats with one blue eye do not appear to have a higher risk of deafness than normal.
There’s only cause for concern if your cat’s eyes change colour when they are over 12 weeks old. Or if they suddenly change colour at any age. There are various disease processes that can cause an eye to change colour. If this happens, then you should speak to your vet as soon as possible.
Can cats have a single eye with two different colours?
When cats have two different coloured eyes this is known as complete heterochromia. But there is also a condition known as sectoral heterochromia. This is when a single iris contains two or more colours. For example, half is blue and half is green. This is a result of an inconsistent distribution of pigment within the iris.
