(, 'Blue Eyes') was a

breed A breed is a specific group of breedable domestic animals having homogeneous appearance (phenotype), homogeneous behavior, and/or other characteristics that distinguish it from other organisms of the same species. In literature, there exist seve ...

of shorthaired domestic

cat The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the ...

with unusual blue or odd eyes caused by a dominant blue eye (DBE) genetic mutation. The breed came in all coat colors; however, only particolors ( bicolors and tricolors), colorpoints, and intermediate colors with a characteristic white tail tip were permitted. The breed also had a semi-longhaired coat variety, the Longhair. Due to the lethal side effects of the gene, breeders stopped working with this blue eye mutation.

History

In the 1980s cats with dark blue eyes were discovered among feral cat populations in

New Mexico New Mexico is a state in the Southwestern United States, Southwestern region of the United States. It is one of the Mountain States of the southern Rocky Mountains, sharing the Four Corners region with Utah, Colorado, and Arizona. It also ...

. The first cat with the characteristic, discovered in 1984, was a

tortoiseshell Tortoiseshell or tortoise shell is a material produced from the shells of the larger species of tortoise and turtle, mainly the hawksbill sea turtle, which is a critically endangered species according to the IUCN Red List largely because of its ...

named Cornflower. She was bred to males without the trait, which proved to be dominant, as all her kittens showed it. The breed was founded and named ,

Spanish Spanish might refer to: * Items from or related to Spain: **Spaniards are a nation and ethnic group indigenous to Spain **Spanish language, spoken in Spain and many countries in the Americas **Spanish cuisine **Spanish history **Spanish culture ...

for 'Blue Eyes'.

Registration and popularity

have always been a very rare breed. In 1992, only ten cats were known. The breed, in both short and long hair variety, was accepted for registration by TICA in 1991. The TICA Breed Group Standard is dated January 5, 2004. Only cats descending from the original foundation female ''Cornflower'' and expressing the deep blue eye gene have been called . It was discovered that cranial defects may be linked to the gene, and breeding was temporarily suspended. Eventually, breeders stopped working with cats bearing this blue eye mutation and the breed became officially extinct.

''Ojos Azules'' gene

were remarkable for their deep blue eyes. The depth of color in the eyes is described as being greater even than that seen in a Siamese and does not cause squinting,

deafness Deafness has varying definitions in cultural and medical contexts. In medical contexts, the meaning of deafness is hearing loss that precludes a person from understanding spoken language, an audiological condition. In this context it is writte ...

or cross-eye. This eye coloration depth in is due to currently unknown polygenetic variations. Unlike the blue eyes seen linked to the genes in solid white, bicolor, and colorpoint, all of which suppress pigmentation, this gene is not linked to any specific fur color or pattern, giving the opportunity to have cats with dark coats and blue eyes. The blue eye color seen in cats such as the Siamese and the is due to the same physical phenomenon, the absence of melanin in the iris. Although the cause of the absence of pigment differs between Siamese, white cats, and , the result is pigment loss and blue eyes. One indicator of the gene was a flattened, white tail-tip. Following a genetic investigation by Solveig Pflueger, breeding resumed in a small way with attempts to breed without the lethal genetic defects. It was discovered that when the gene is

homozygous Zygosity (the noun, zygote, is from the Greek "yoked," from "yoke") () is the degree to which both copies of a chromosome or gene have the same genetic sequence. In other words, it is the degree of similarity of the alleles in an organism. Mos ...

it caused cranial deformities, white fur, a small curled tail, and stillbirth. However, when the gene was

heterozygous Zygosity (the noun, zygote, is from the Greek "yoked," from "yoke") () is the degree to which both copies of a chromosome or gene have the same genetic sequence. In other words, it is the degree of similarity of the alleles in an organism. Mos ...

, those lethal genetic mutations did not manifest. The result was that breeders crossed the blue-eyed cats with non-blue-eyed cats, assuring a litter of about 50/50 blue/non-blue-eyed kittens.

Description

Appearance

The medium-sized was known for its bluish eyes, which were large and round. The neck was arched. The tail was proportionate to the cat's body. The head was somewhat triangular in inscribe. It had a slightly rounded forehead and an angular muzzle. The nose had a slight break. The coat was short, fine, soft, silky, and shiny. The undercoat was not particularly developed, but most were dense in color. All colors were allowed. However, only particolors ( bicolors and tricolors), colorpoints, and intermediate colors with a white tail tip were permitted. White markings were common on most extremities (tip of the tail, muzzle, and paws). However, belly spots or chest spots were not acceptable and were considered faults. Solid white coats were not desirable, as they could only be distinguished from common white blue-eyed cats with genetic tests. Solid white blue-eyed were susceptible to deafness, as is common in white blue-eyed cats without the mutation.

Revival of dominant blue eyed breeds

Apart from the extinct , several other dominant blue eye (DBE) genes have been found in cats worldwide. These are not , as they are not descending from Cornflower. The cats bear DBE mutations, and are developed into new cat breeds or approved as eye coloration variants in existing breeds by certain

cat registries A cat registry or cat breed registry, also known as a cat fancier organization, cattery federation, or cat breeders' association, is an organization that registers domestic cats (usually purebred) of many breeds, for exhibition and for breedin ...

References

{{Domestic cat Cat breeds Cat breeds originating in the United States Experimental cat breeds Extinct cat breeds