Genetics Picture

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The albino series
(Himalayan/Siamese coloring, Burmese coloring, albino)

The albino series consists of five alleles. The gene for normal color, for example black, is dominant and is represented by C. cb is the gene that gives the paler color of the Burmese, the black cat becomes brown. cs gives Siamese coloring, ca gives a white cat with blue eyes, a blue eyed albino. This cat is not to be mixed up with the more commonly dominant white cat, which also can have blue eyes. And at last there is a gene called c. It gives genuine albino cats, which are white cats with red eyes.

The cb allele is not fully dominant over the cs allele. A cat with the genotype cbcs has a coloring inbetween Burmese color and Siamese masking. The color of the eyes is turquoise. This coloring represents a special breed, not yet recognized in FIFe. It is called Tonkinese and cannot be pure bred. In a mating between two Tonkinese there is a 25% chance of getting Siamese masked kittens, 50% chance of getting Tonkinese and 25% of getting Burmese colored kittens.

The Siamese colored kittens are born completely white. The color of the mask doesn't appear until after a week. This is due to that the cells of Siamese colored cat cannot develop any pigment if the temperature is too high. When the kittens are in the womb of their mother's they are warm and comfortable, and no pigment at all is developed. When they are born it becomes cool enough for the pigment to develop on the cooler extremities, like for instance ears, legs and tail. This temperature dependant pigment production is called acromelanism. Acromelanism is present in other animals, for instance in rabbits.

The color snow leopard, present in Bengals, is primarily a masked cat with relatively weak contrasts between mask and body. The dots can therefore be seen all over the body, but the markings are a bit darker in the face, on the legs and on the tail.

Foreign white is a Siamese with the gene for dominant white, W (see below). The result is a completely white cat with the dark blue eyes of the Siamese. A normal white blue eyed cat has considerably lighter eyes.

Denominations: C = normal colour
               cb = Burmese
               cs = Siamese
               ca = blue-eyed albino
               c = true (red-eyed) albino

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