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Are all white cats deaf?

Why Are White Cats With Blue Eyes Deaf?

Deafness in white-furred cats with blue eyes is highly prevalent due to a shared gene that is connected to inherited deafness in cats.

November 30, 2021 4 min read

Nothing is as striking as seeing a snowy white cat with crystal clear blue eyes. But, it may come as a surprise to learn that most white-coated blue-eyed cats are deaf. But what is the reason for deafness to become so prevalent in white-coated cats? It turns out that inherited genes from the parent cats have a great deal with inherited deafness. Below, let’s take a closer look at these beautiful cats to understand better why white cats with blue eyes have a higher likelihood of inherent deafness.

How Do Genes Play a Role?

Genes make up who we are, and the same is true for animals. Just as human genes may influence what color hair we have or how athletic we are, a cat’s genes can determine its appearance and possible inherent traits, like deafness. It turns out that there is a strong link between the genes that create a white coat and blue eyes with deafness in cats.

Geneticists and cat breeders have long been fascinated with the connection between deafness and cats with white fur and blue eyes. Scientists have determined that one dominant gene, called W (for White), creates the snow-white coat coloration. This gene is also responsible for creating blue eyes and deafness.

If a cat carries the W gene, it will have a white coat with 100% certainty. However, if the cat carries the W gene, it may also have an equal likeliness for both deafness and blue eyes. Having equal chances of developing these two traits makes the gene incredibly linked to both eye color and inherent deafness. While the vast majority of white-coated, blue-eyed cats are deaf, not all are. Scientists believe that environmental factors and other recessive genes may contribute to the W gene, also contributing to deafness in cats.

How Likely Is Deafness in White Cats?

White cats are extremely popular with pet owners but only make up about 1.5% of the total cat population. Some white cats may have green or golden eyes, but a significant amount will have one or two blue eyes. It turns out the chances of having a deaf white-furred cat with blue eyes are rather substantial, which is all related to the same shared W gene that carries fur color, eye color, and inherited deafness. Cats with long white fur and blue eyes are three times more likely to be deaf.

If a white-furred cat has two blue eyes, the chances of that cat being deaf are between 60% and 80%. Shockingly, a white-furred cat with only one blue eye drops to only a 30% to 40% chance of being deaf. A white-furred cat with gold, green, or brown eyes only has a 10% to 20% chance of being deaf. When comparing these statistics to other cats with different fur colors, scientists find that deafness in non-white cats with any color eye color deafness is extremely rare. Non-white cats make up over 95% of the population, proving that deafness in white-furred cats is highly prevalent.

Is There a Test for Deafness in Cats?

Having a white cat is highly desirable, and some breeders will only work with white-furred cats. Because deafness is so prevalent in white-furred cats, breeders will regularly have to test for deafness in new kittens to properly manage and care for their cats. Luckily, there is a non-invasive and safe test that can quickly identify deafness in cats.

The BAER test is a simple test that a veterinarian can perform. The brainstem auditory evoked response test can be performed by a specialist and looks for an immediate response in cats. The test takes about 5 to 15 minutes to perform, and most cats can undergo the test without sedation. Not only does the test look for a hearing response, but it examines the structure of the ear to determine if deafness is present.

What Are the Challenges with a Deaf Cat?

Although there may be different challenges and aspects to raising a deaf cat as a pet, they are often just as healthy and vibrant as a cat that can hear. As a pet owner, you may have to take certain precautions to keep your pet healthy and safe. If you own a deaf cat, here are some best practices and tips for keeping your pet happy.

  • Be Mindful of Vibrations — Deaf cats are often more sensitive to movement and vibrations. Be sure to move carefully around your cat. Because your cat cannot hear, using vibrations to get their attention or wake them from sleep could be a viable means of communication.
  • Indoors Only, Please — Deaf cats are not able to hear approaching predators or passing cars. The outdoors can be an extremely dangerous place for a deaf cat. Always keep your deaf cat as an indoor cat only.
  • Hand Signals — Many deaf cats can quickly learn hand signals and motions. Teach your cat sign language when it is time to come, eat, or get off the sofa.
  • Approach From the Front — Deaf cats can be startled if you sneak up behind them. Be sure to always approach a deaf cat from the front, so it can see you coming.

Everything You Should Know About White Cats

Everything You Should Know About White Cats

Few people can deny there is something special about a white cat. The gentleness and pureness associated with the color white definitely translates to these incredible creatures.

In cats, the genetics behind the white fur are fascinating. We’ll cover it all and as well as breakdown the link between white fur and deafness and the difference between a white cat and an albino cat.

Are white cats common?

No, white is the most rare color found in cats.

What are the most common breeds that have white cats?

American Shorthair, Devon Rex, European Shorthair, Maine Coon, Oriental, Persion, Siamese, Siberian, Turkish Angora, and Turkish Van.

Do white cats have long or short hair?

They can have both!

What color eyes do white cats have?

Usually blue, but they can also have gold, green, yellow or amber eyes.

Why do white cats usually have blue eyes?

When the cat is an embryo, stem cells will migrate to different parts of the body and become specialized cells. These stem cells transform to melanocytes in a number of areas of the embryo, including the outer surface, where the skin and fur will be, as well as the eyes.

Melanocytes are cells that contain the pigment melanin (just like in people). With melanocytes either non-existent or in very small amounts in the eyes of white cats, the eyes will be blue.

We’ll keep referring to melanocytes and melanin because they explain a lot of the white fur and blue eye coloring in white cats.

Why do blue-eyed cats have red eyes when a camera flash goes off?

Most cats have a colored mirror in their eyes that reflects light called the tapetum lucidum. Cats with blue eyes don’t have one, so just like humans, when light reflects off their eyes, it’s reflecting off blood vessels in the retina, and a redish pinkish color is captured. These cats likely cannot see as well in the dark as cats with non-blue eyes.

Is it true white cats with blue eyes are deaf?

Some white cats with blue eyes are deaf, but not all of them. There is a band of melanocytes that regulates ion balance in the ear, which plays a crucial role in transmitting sound signals to the brain. If the ion balance is off when the kitten is a few days old, the signals don’t make it to the brain and deafness occurs a few days after birth.

Since a lack of melanocytes plays a role in blue eyes and white fur, it makes sense that the lack could also happen in the ear (causing deafness). However, deafness is still related to a gene, and not all white cats with blue eyes have the gene associated with deafness.

Studies show a lot of varying stats regarding deafness, as you can see in the ranges:

  • 2-5% of cats are white
  • 15-40% have at least one blue eye, and 60-80% of these cats are deaf
  • 30-40% of white cats with blue eyes are deaf
  • 10-20% of non-blue-eyed white cats are deaf

What causes some white cats to have different colored eyes? Is it true the white cat will always be deaf in the side with the blue eye?

The condition of odd-eye colors is called heterochromia. We already discussed the decrease in melanocytes and melanin in white cats. If the melanocytes don’t make it to one of the eyes, it will be blue. The odd colored eye means the melanocytes made it to the eyes and were able to produce melanin (pigment).

The cat may be deaf on the same side it has the blue eye because lower melanocytes cause blue eyes, and it means there’s a greater chance of less melanocytes in the ear on the same side. If the odd-eyed cat can hear on both sides, there wasn’t a lack of melanocytes in the ear, but there was in the eye.

Is it true deaf white cats have helped people with hearing loss?

Yes, deaf white cats have been heavily involved in the trials and research for cochlear implants.

What genetically determines a cat will be solid white?

Usually, solid white cats have the dominant white gene (W), and although there are other genes present for fur and eye color, the dominant gene wins out, and there is no pigmentation.

It’s very fascinating because the gene is actually masking the real color of the cat! When a dominant white kitten is born, they’ll often have a few hairs on their head that show their real color, and those hairs disappear after a few months. (I have a solid white cat and she had a few black hairs on her head as a kitten, so the color the white is masking for her is black.)

A cat can also be white from the white spotting gene (S). While it creates visible white spots on bi-color cats and calicos, it also can create a white spot that covers the cat’s entire body. Graded on a scale from 1 to 10, 10 is completely white and extremely rare.

What’s the difference between a white cat and an albino cat?

Albino cats are born with a missing or damaged TYR gene. This means they don’t have the enzyme tyrosinase, which is needed to produce melanin. Albinos have no pigment. Their eyes are the palest blue, or can even appear pink. Their skin also appears pink.

The pinkish color come from light reflecting off blood vessels in the eyes and blood flow under the skin. To contrast, my dominant white cat has skin that is extremely pale and looks almost off-white in most areas, with maybe a tiny bit of pale pink.

White cats have melanin, they just have less of it than cats with fur of other colors. Where white cats have genes that create white fur, often masking other colors in their genetic makeup, albino cats have zero color in their genes and zero melanin.

A little crazy fact – there is something called partial albino (which is exactly what it sounds like), and the pointed pattern of Siamese, Burmese, and Tonkinese cats has its roots in partial albino lineage!

Do albino cats have more health issues than white cats?

Yes. The lack of melanin raises a number of issues:

  • Their skin and eyes are more sensitive to the sun. They have a higher rate of skin cancer and their eyes can suffer sun damage from direct sunlight.
  • They do not have good depth perception, focusing, and tracking, making them a bit clumsy and not the most accurate during hunting or playtime activities.
  • They are more susceptible to illness because melanin plays a role in the strength of the immune system.

How long do white cats live? What about albino cats?

Indoor white cats live just as long as any other type of cat, which according to the ASPCA is 13-17 years. As long as an albino cat lives indoors, they too have normal lifespans.

If an albino is in the wild, their lifespans are much shorter because they are often not great hunters (because of the issues mentioned above) and have problems surviving.

What are white cats’ personalities like?

There doesn’t seem to be a connection between coat color and personality, but there are perceptions people have developed. Owners say white cats are antisocial, shy, calm, and lazy.

My white cat is the most social and friendly in the household – cat personalities really depend on their early lives, as well as paternal genetics, which we very often don’t know.

Are there any diseases that seem to be genetically tied to white cats?

While not genetically tied, they do have an increased risk of skin cancer because of the decreased amount of melanin in their skin. Be sure to limit their sun exposure, check for tumors on the eyelids, ears, and nose, and take them for annual vet appointments.

According to Merck Veterinary Manual, the most commonly reported congenital and inherited defects in cats are:

  • Cerebellar hypoplasia (CH) aka Wobbly Kitten Syndrome — Underdeveloped cerebellum (which controls mobility and balance)
  • Eye and eyelid defects
  • Heart defects
  • Cryptorchidism — One or both testicles absent
  • Polydactyl — Extra toes

In Closing

Although white cats are rare in the cat world, they represent enough of the cat population that if you want to add one of these beauties to your home, you should be able to. Just keep an eye on postings from you local rescues and shelters, but make sure to make a move as soon as you see them. Their rarity makes their demand a little higher than other colors.

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