Prior to the emergence of amber there had never been any scientific evidence of a yellow recessive mutation (e) in the extension gene in cats. That is why in non-agouti cats the nose remains black and in agouti cats it remains pink.
#Silver tabby cat with amber eyes skin#
Amber cats are basically black cats with a colour modifier that affects the deposition of pigment on the hair shaft, but not the skin colour. Rui's theory is that the amber gene invalidates the action on the non-agouti gene wide-banding will further lighten the base colour giving a very pale cat with black nose and paws. According to Rui Pacheco, although this cat is clearly non-agouti because of the black nose, he has the phenotype of a silver shaded. The photo below shows a non-agouti amber. The name comes from the effect of black or brown pigment not being extended throughout the whole coat, but being restricted to the skin of the extremities and to the eyes (for example in bay horses).Ī non-agouti amber Norwegian forest Cat resembles a silver tabby, but has a distinctive black nose and black paw-pads instead of the pink/reddish nose with black outlining found on conventional silver tabbies. The dominant version of the gene produces normal black pigment in the coat while the recessive version produces red pigment. The Amber effect is due to the extension gene (also called red factor) which controls the production of red and black pigment. They are now called Amber and Light Amber. These cats were a totally new colour, peculiar to the Norwegian Forest Cat gene pool and dubbed the "X Colours". Had the gene pool become polluted by someone, perhaps generations ago, breeding their Norwegian Forest Cat to another breed? Was it a spontaneous mutation? Crossing of those cats with known chocolate and cinnamon colour cats of other breeds ruled out chocolate/lilac and cinnamon/fawn genes. However, those colours are not found in the purebred Norwegian Forest Cat gene pool. Their original birth colour could be seen only on the back and tail.ĭuring the 1990s, some purebred Norwegian Forest Cats in Sweden produced chocolate/lilac and cinnamon/fawn offspring. Amber has also occurred in conjunction with silver: the kittens were born as poorly coloured black-silver or blue-silver tabbies whose tabby ghost-markings faded as they matured and their colour became a bright apricot to cinnamon colour with dark brown paw pads and nose leather with no black rim (the black rim is characteristic of silvers). At birth, kittens appeared to be black or blue, and lightened to Amber or Light Amber respectively. The Black Modifier gene, found in Norwegian Forest Cats, brightens black or blue areas of the coat to Amber (apricot-to-cinnamon colour) and Light Amber (pale beige). Amber and russet can occur in solid or tabby-pattern cats.Ī "late colour change" mutation, again causing an end result of golden, has been observed in Norwegian Forest Cats. Recently a number of Siberians and Kurilian Bobtains have been wrongly registered as “amber.” These may be a separate mutation called “sunshine” found only in those 2 breeds, or may be a newly emerging recessive gene. Mutations continue to occur and unexpected colours also turn up due to inbreeding where recessive genes, hidden for generations, start showing up.Īmber and Russet cause the coat colour to change from a black or blue colour to a reddish or golden colour as the cat matures. A few other genes give further variations on those colours such silvers, colourpoints and solids/selfs. Eumelanin gives the blacks, browns and blues while phaeomelanin gives the reds, fawns and creams. Over the centuries, mutation produced a wide array of colours based on 2 different pigments. The ancestors of the domestic cat were nondescript black/brown striped tabbies. EXTENSION GENE: AMBER AND RUSSET - LATE COLOUR CHANGE GENES
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