The secret of cats with heterochromatic eyes
ODD EYE: Heterochromia iridis
The English word "odd" means odd number, which means the remainder, so cats or dogs The discoloration of one of the iris in a dog's pupils is called heterochromia. Although there is the word "disease" in it, it is not a disease, it just describes the condition of heterochromatic eyes, which is commonly known as mandarin duck eyes.
Having heterochromatic eyes is a symbol of luck
In ancient Japan, cats with both golden eyes and blue eyes were called Kineye Gineye and regarded them as A symbol of luck, Thailand, the country where Siamese cats originate, calls the cat’s heterochromatic pupils “diamond pupils”. Things are rare and valuable because the number is small, so if they encounter such a cat, they will Consider it a symbol of good luck and take it very seriously.
Heterochromia iridis is a disease in humans. It may be caused by congenital genetic genes, or it may be caused by iris injury caused by acquired diseases or trauma.
What breed of cats are more likely to have mandarin duck eyes
Cats with mandarin duck eyes are generally more likely to appear in white cats or cats with more white hair. Purebred Turkish Van cats, Angora cats, and Japanese bobtail cats are also more likely to appear. Especially among Japanese bobtail cats, tricolor cats with blue eyes or heterochromatic pupils often appear, so some breeders will use selective mating to greatly increase the probability of giving birth to heterochromatic pupils in their offspring. Tricolor cats with blue or heterochromatic pupils have most of their bodies covered in white hair, with only orange or black hair appearing on the head and tail.
The genetic factors of white hair and blue pupils
Why are cats with blue pupils more likely to have hearing impairment? Like Siamese cats and Himalayan cats, although their eyes also have blue pupils, they do not suffer from hearing impairment. Cats with hearing impairment are basically concentrated in cats with white fur and blue pupils. This has a certain relationship with genetics.
Except for cases where the coat color degenerates into white due to sudden changes in the body, cats with white hair can generally be divided into two types:
White genetic factor (W genetic factor) )
The first type is to have a white genetic factor that can cover up all other colors in the body. This is a dominant genetic factor. It can suppress all other genetic factors in the body that can determine the color of a cat's coat. Otherwise, they would function, which we also call genetic markers.
White spot genetic factor
Another situation is that cats with white hair on a certain part of their body, like black and white or orange and white, are caused by the white spot genetic factor in the body. effect.
What we think can affect eye color and hearing is the white genetic factor (W genetic factor). The W genetic factor does not contain melanocytes, and the lack of such melanocytes also affects the cat's eye color, causing the eyes to appear blue. So blue eyes do not mean that the eyes are blue, so they look blue, but that the eyes lack melanocytes, so we look blue.
Hearing impairment is caused by incomplete development of the sensors in the cochlea. Because sensors are differentiated from the same cells as pigment cells, due to the influence of the W genetic factor, the lack of melanocytes affects the sensors, resulting in hearing impairment.
The formation of coat color, eye color, and hearing organs are all related to melanocytes, so the degree of influence of the W genetic factor on melanocytes determines whether cats’ eye color is blue and their ears Will you become deaf?
60-80% of white cats with blue pupils will have hearing impairment, while about 10-20% of white cats with non-blue pupils will have hearing impairment. For a cat with heterochromatic eyes that has a blue pupil, the probability of having a disorder in the ear with the blue pupil is about 30-40%.
There are also some cats with white fur and blue eyes whose hearing is normal in their childhood, but their hearing will decline when they are 5 to 6 years old.
Many researchers also say that cats’ blue eyes and hearing impairment are jointly determined by more and more complex genetic factors, so there are still many mysteries in the world of cats. Maybe One day in the future, new genetic factors that determine eye color may be discovered.
Cats with white fur and blue eyes lack melanocytes in their bodies, so they are less adaptable to direct sunlight. If you have such a cat at home, please be careful. If your cat unfortunately develops hearing impairment, you don’t need to worry too much in the environment it is accustomed to. However, you should be careful not to suddenly pet it while it is sleeping. You should walk a little heavier when passing by it to let it go. It can feel vibrations and is used to you telling it that you are coming to it.