A cat with eyes of different colors looks mesmerizing. Who would refuse such a pet, which arouses persistent interest and admiration among guests and friends! People even start looking for a breed of cats with different eyes, not understanding the reason for this unusual phenomenon.
I am in a hurry to disappoint – such a breed does not exist. The good news is that kittens with different eyes are found in any cat breed, for which we assume a solid white or turtle color.
How it turns out that cats with different eyes color
Different eye color has a scientific name – heterochromia. Heterochromia is found in cats and dogs, horses, and even humans (although sporadic).
Complete heterochromia – when each eye is colored in its own color, and partial heterochromia – when two colors are combined in the eye’s iris. Partial heterochromia is really rare, but you will not surprise anyone with entirely different eyes in a cat.
At full heterochromia, one eye will always be blue, and the other will still be any color: yellow, green, orange. The secret is that cats’ blue eyes are not the color at all, but its absence. In other words, the color is genetic, but something has prevented the pigment from migrating to the iris.
The pigment is distributed at the moment when the kitten is still in the mother’s womb. It is impossible to influence this process, and so is the prediction. Therefore, breeding a “breed of cats with different eyes” is simply impossible.
Why does disagreement occur regularly in specific breeds or breeding lines? The white color is to blame for everything! The white color gene (W – white) doesn’t carry information about the color, but simply suppresses all other colors. A snowy white cat may well give birth to colored kittens, if it is secretly not white, but red or black. This white gene also violates the pigment in one eye – or both, as it turns out. In other words, some kittens will have green or yellow eyes, some will have blue eyes, and some will have different eyes.
Does it affect the health of the kitten?
Eye color has no effect on the cat’s vision. But if different eyes appeared under the dominant white gene’s influence, the cat may have hearing problems. The fact is that W-gene inhibits the migration of melanoblasts cells to the iris and the inner ear, disrupting this organ’s development.
That is why white cats sometimes suffer from congenital deafness. The problem often concerns blue-eyed animals (the gene’s action is manifested as much as possible).
Still, contrary to the general misconception, a white cat with colored eyes can also be deaf. If one eye is colored and the second one is blue, the cat may be deaf from the blue eye, and it is customary to hear with the second ear. In this case, the owner will hardly notice any problem. It will be possible to check the cat’s hearing only with special tests under anesthesia in the veterinary clinic.
Deaf cats should be strictly rejected. They are not allowed to breed – this applies to any breed. In addition, two white blue-eyed individuals should not be crossed with each other, even if both cat and cat hear perfectly.
Breeds of cats with different eyes
So, there is no blue-eyed gene, no deafness gene, and no discord gene. Why does the Internet persist in offering some breeds of cats as “discord”? These are the breeds where the snow and white color:
- is the only acceptable color: Kao mani;
- is very common: Turkish Angora;
- is combined with colored spots: Turkish Van.
Different eyes are often found in breeds of cats. White color is the only tolerable variety, not the main feature of the breed. Breeders have a theory that to get kittens with heterochromia, white animals must be crossed with two-colors.
Such animals are also called pegs: white spots alternate with painted areas. If the white spots are very, the cat may look completely white (a spot of color may be on the tail, on the head). This white color is not caused by the gene W, but the spot is S (spot) by the white peg leg gene. Gene S also disrupts the migration of melanocytes to the wool and sometimes to the eyes, but does not cause deafness. Since the spots are asymmetrical, it is not surprising if one eye is dyed and the other is not.
Read also about 20 unknown facts about cats
There is another pattern: if a kitten (or several) with different eyes was born in the litter, these parents would likely get stable kittens with heterochromia in the next litters.
Thus, eyes of different colors can be found in cats of any breed. The standards we assume white or spotted color – Cornish Rex, Sphynx, Maine Coon, Persian cats and exotics, British cats and many others.
Do not discount the usual pedigree cats – mestizos, who also often have heterochromia. It should be said that a discordant kitten has a dramatically increased chance of finding a home – many are willing to take such an unusual pet, even if it is “noble” blood. Such cats will never bite you 😜
It is believed that cats with different eyes bring good luck to the owner and have strong magical powers. And even if you are far from esoteric, it is impossible to deny that cats with heterochromia look very impressive and mysterious.
One of my acquaintances even found his mongrel cat a “bride” in the hope of getting a discordant kitten. Unfortunately, white Dobby (one eye yellow, the other blue) and white blue-eyed cat had kittens with the same yellow or blue eyes. Two of them were cream color, two were white and both white kittens were deaf.
There is another reason why a cat may have extravagant color (like a two-faced Venus cat, for example) or eyes of different colors.
Cats are multi-berry animals. Occasionally, two fertilized eggs, instead of quietly attaching to the uterus wall and develop further, merge into one. It turns out one healthy, viable kitten, but with a double set of chromosomes. This phenomenon is called chimerism.
Embryo fusion – it sounds pretty creepy, but in fact, such animals live quietly, bring offspring, and no one even knows what an unusual creature is sheltered at home. You can’t consider a cat a chimera just based on a strange color, to confirm it you need genetic tests (which no one is in a hurry to perform).
Also, cats may have mosaicism – areas of cells with DNA differences resulting from the mutation. Mosaicism is often “blamed” for the appearance of hair areas of “impossible color”, partial eye heterochromia, complete heterochromia in turtle, colored cats. The difference between a mosaic and a chimera is that the mosaic mutations occurred based on its own cells. In contrast, the chimera has two complete and different sets of chromosomes that were not mutable.
It makes sense to suspect such deviations if cats have different eyes, but neither is blue. For example, one is yellow or orange, the other is green. Interestingly, heterochromia variants in completely colored cats – this is much rarer than in white animals, but still happens!
From what age you can determine the different eye color of a kitten
If before heterochromia was considered a genetic anomaly and did not welcome such kittens’ appearance, now it is just the opposite. Breeders fight over the unravelling of genetic algorithms responsible for eye color in cats, and kittens with heterochromia are welcome and in demand.
But when kittens only open their eyes, they all have the same “baby” blue color.
The accumulation of pigment in the iris occurs gradually, and with age, the color of the eyes changes. It is guaranteed to determine heterochromia at 2.5-3 months.
Experienced cat guides, however, know that you can learn eye color before. For this purpose, kittens are examined in a dark room with a weak light source. Blue eyes burn red and the rest green.
Fix the different colors of the eyes and pass it on to the offspring is not yet possible. If someone tells you that there is a breed of cat with different eyes, know it’s a myth.
Do not cross pure white animals with different eye colors in the hope of getting an unusual offspring with heterochromia: remember the negative impact of gene W on your hearing.
If you are the lucky owner of a pet with heterochromia, send us your photos. With your permission, the article will be updated.