Golden, Sunshine, Copper, Sorrel, and just pretty are all vanity names for CORIN, the colorations created by mutations affecting the length of pheomelanin in each hair.
CORIN could easily be considered one of the anecdotally referred to but unknown “rufous polygenes” that create warm reddish tones in domestic cats. It has been identified in tigers, Siberian Cats, British Shorthairs, and Bengals. Asian Leopard Cats too, have been identified with a unique CORIN variant now also found in Bengal Cats.
It doesn’t change the eumelanin-based color of a cat, but it adds more reddish/yellow/golden tones to the background coloration of the cat. This often allows more of the background color to be visible and allows the darker pattern to appear clearer or crisp.
In Siberian Cats two versions of CORIN, wbeSIB and wbSIB, have been identified that create a slightly different colorations . One of the variants creates a greater degree of white around the eyes and lighter undersides.
A unique variant found in the British Shorthair, WBSH, create a coloration often called Copper by the breeder community. This version of CORIN also allows for eumelanin expression, not changing a cat from a Black or brown tabby but creating a vibrant coloration to the animal.
Toyger and ToyBob cats also have been identified as having CORIN present among members of their gene pool that are part of the 99 LIVES dataset.
