Why are white cats deaf?

Question

Why are white cats deaf?

Answer 1

Hi there...contrary to belief not all white cats with blue eyes are deaf.

Here's an article found from messybeast.com that explains this more in detail:

WHITE CATS AND DEAFNESS

(For the full complete article)

http://www.messybeast.com/whitecat.htm

A few years back I was asked three related questions on a newsgroup. This article is adapted from my answer.

- Are white cats, particularly blue eyed white cats, always deaf or is this an old wives' tale?

- Is deafness linked only to odd-eyed white cats?

- Some blue-eyed whites aren't deaf - why?

There is an established link between the white coat color, blue eyes and deafness. The tapetum lucidum is generated from the same stem cells as melanocytes (pigment cells). The blue eyes in a piebald or epistatic white cat indicates a lack of tapetum. Deafness is caused by an absence of a cell layer in the inner ear that originates from the same stem cells as well. In odd-eyed white cats, the ear on the blue-eyed side may be deaf, but the one on the orange-eyed side usually has normal hearing. Not all blue-eyed whites will be deaf since there are several different genes causing the same physical attributes (whiteness, blue-eyedness) so it all depends on the cat's genotype (its genetic make-up) not its phenotype (its physical appearance). Some people claim that 99% of blue-eyed white cats are deaf. This is inaccurate because blue-eyedness and whiteness can both be caused by different genes. It all depends on what genes the cat has inherited. These are the actual figures from scientific studies around the world. The percentages are given in ranges because results are different in different areas, partly because of the different genes found in the cat population. Where a cat is classed as deaf, the deafness may affect one or both ears.

...It is evident from those studies that blue eyed whites exhibit a higher incidence of deafness than do orange/green eyed whites or non-white cats! But not all blue eyed whites are deaf and here's why:-

There is a known link between white coat color, blue eyes and deafness - but since the coat and eye color can be caused by different genes it means that only some blue eyed whites are deaf. There is a gene/gene complex which causes white coat, blue eyes and deafness, but not all cats get their white coat and blue eyes from that particular gene, so not all white cats will be deaf.

If the cat is a Foreign/Oriental White, it carries the gene for 'Siamese Blue Eyes' which is not linked to deafness (the gene for Siamese Blue Eyes is linked to cross-eyes instead). Siamese blue eyes have a reflective tapetum, but this is depigmented because the Siamese colour is caused by albinism. This depigmentation gives the red-eye with flash cameras. Random matings can mean that this gene sometimes appears in non Oriental-looking cats which have colorpoint cats in their ancestry.

...

So overall, blue-eyed white cats stand a higher than usual chance of being deaf; but they are not guaranteed to be deaf. Odd-eyed white cats may be deaf on the blue-eyed side. If you have a deaf white cat, it is not advisable to breed from it as this would pass the trait along. Deaf white cats are banned from exhibition or breeding by some fancies in Europe and there is a move to reduce or eliminate this trait from British breeding lines of various breeds. Deafness can cause problems because a cat cannot hear danger approaching. It can cause problems to breeders because deaf female cats cannot hear their kittens crying out and may neglect them. Deaf kittens cannot hear their mother calling to them and may get lost. Deaf cats also seem to have no volume control when meowing.

Answer 2

Not all white cats are deaf.

Answer 3

My little Luna is deaf.  He is all white (except a faint yellow streak through his tail, which we think comes from the fact his mother was white with ginger markings, so maybe this was the ginger attempting to come through) and has the most piercing blue eyes ever.

I've read that white cats with two blue eyes will be deaf.  If they have one blue eye and one other coloured, they will be deaf in the ear on the same side as the blue eye.

Anyone worried about taking on a deaf cat needn't worry.  Luna is an indoor cat and is just as active as his hearing brother.  Yes, you need to be careful not to scare him when coming up behind him, but a good thud on the floor when you enter a room usually alerts him to your presence.  He is hilarious when 'stalking' his brother as he usually walks slowly over the top of newspaper or plastic bags, so it's obvious from miles away that he's about to pounce.

Answer 4

that sounds like a very racist remark, I may as well ask why all black cats are lazy!

Answer 5

i dont know.

my friend had a pure white cat and it had no ears.

i think they havd to be removed for some reason...

Answer 6

That's not true.

I've heard that bout cats with blue or different colored eyes also.

Answer 7

Not all of them are but they are more likely to be, especially if they are blue eyed. It is a genetic trait.

I've had 2 white cats, one deaf, one not.

Answer 8

They're not always. Albino animals are quite often deaf but not all white cats are considered albino.

Answer 9

what? not ALL white cats are deaf

Answer 10

If a cat is pure white with two blue eyes, most likely he is also deaf.  A white cat with any body or different eye coloring should have his hearing.