The back of the eye also lacks pigment, giving colorpoint cats' pupils an eerie red and silver reflection in the dark, unlike a normally pigmented cat's shining silver-green or -blue. A cat (of any breed) with this coloration is often called a colorpoint cat to distinguish it from others.Īs the expression of the gene responsible for the pointed pattern is regulated by temperature, pointed cats who live in cooler environments often show increased darkening of their fur relative to cats who live in warmer climates, sometimes even developing large dark areas along their sides.īecause of the pigment restriction caused by the temperature sensitive tyrosinase, pointed cat's eyes are always shades of blue because the blue layer in the eye common to all cats is not covered by another color. It is also possible to have a tortoiseshell or tabby point. It is possible to have a red (orange color) or fawn (pale warm gray) point. Points are not limited to solid colors or dark colors. As the kitten ages, the cooler areas darken while warmer areas remain cream to white in color. Pointed kittens are born white, since the womb is uniformly warm. As a result, dark pigment is limited to the coldest areas of the body, that is, the extremities. The mutated enzyme is thermolabile it fails to work at normal body temperatures, but becomes active in cooler areas of the skin. It is a form of partial albinism resulting from a mutation that affects tyrosinase, an enzyme involved with melanin production. Point coloration in cats originated in the Siamese and closely related Asian breeds, and is found in many Western-developed modern breeds.
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