If you grew up around a lot of cats, you will probably know some male…
Why are white cats deaf? It’s a very good question, and the answer is linked to heredity: the genes that cats inherit from their parents.
First, let’s answer another question: are ALL white cats deaf? The answer to this is no. Deafness is most likely in white cats that have at least one blue eye – but even then, it depends on the cat’s genes.
The white cats that are born with hereditary deafness are blue-eyed, white-coated domestic cats. Like humans, many kittens are born with blue eyes that later change to green or gold, but deaf white cats will almost always have at least one eye that remains blue.
So why are these white cats deaf? The answer is that they carry a dominant gene that causes a white coat and also causes problems with development in the neural crest. This affects both the ear and the eye, causing a lack of pigmentation in the eye (making it blue) and arrested development of the inner ear.
This means that if a white cat has one blue eye, it is likely to be deaf on the same side as that eye. If a white cat with the dominant gene has two blue eyes, it is likely to be deaf in both ears. In some cases, they have a partial hearing loss, but over 70% of these cats will be completely deaf.
But cats can be white for different reasons. For example, there are albino cats. Albinism is caused by a genetic abnormality that removes pigmentation from the skin and hair. Albinos can be deliberately bred, but often the parents are regular cats of any breed. Eyes are pink or bluish-pink. Albino cats are not likely to be born with hearing problems.
Also, cats whose parents are white-spotted may be born with so much white that they appear to be pure white. However, they are really black-and-white cats with no big black spots. In most cases, they do have a little bit of color somewhere as kittens, if you look very carefully. Their parents and their kittens will probably be colored.
This type of white cat is no more likely to be born deaf than the average black-and-white or tabby cat. The same is true of pointed cats who happen to be born white, like white Siamese cats. These cats may even be white with blue eyes or one blue eye, and still have no deafness.
So this means that white cats are only likely to be deaf if they carry the particular dominant white gene that causes both blue eyes (either one or two blue eyes) and deafness. At least one of their parents will have been white and probably deaf too. If you breed from them, there is a 50% chance for each kitten that they will receive the dominant white gene. But when cats are white for any other reason, and they do not have that particular gene, white cats are no more likely to be deaf than any other cat.