The white coat in these cats is caused by a totally different gene to that which causes the white coat in other, recognized, white breeds.
The white coat of White Long-hairs, British Short-hairs and Foreign Whites is due to a dominant gene. In a cat with one or two of these genes thecoat is white, but the eye colour may be orange, yellow, green or blue.
The recessive white coat is produced by a gene very similar to that which produces the Siamese, and in the same series.
The Burmese cat has less pigment than a fully coloured cat. The Siamese has even less pigment, and has blue eyes. The Recessive White has further reduced pigment so that it has a white coat, but it still has blue eyes with pigment in them: because there is less pigment there is a pinkish glow behind the blue. Although these cats are known as Albino Siamese in the USA they are not true albinos as they do have pigment in the eyes.
As these white cats are produced by a recessive gene they must possess two genes for Recessive White in order to be White, (c^c3)- If a fully coloured cat, Burmese or Siamese which carries the recessive white gene (Cca, c^ca or ^c3) is mated to another cat carrying the recessive white gene, on average a quarter of the kittens will be white.
All white cats, whether their white coat is due to the dominant white gene or the recessive white, are more sensitive to sunlight than dark coloured cats. White cats which are subjected to strong sunlight tend to get inflamed skin where they are unprotected by hair: this may produce sunburnt ears or conjunctivitis. The same effect may be seen in Bi-coloured cats which have a white patch over an ear or eye, and is sometimes seen in the more dilute coloured cats such as lilacs or creams.
Dominant white cats with blue eyes may suffer from deafness. This is seen, not uncommonly, in Long-hair, British Short-hair and “ordinary moggies’. Deafness has not been observed in any of the Recessive White cats bred in Britain (about thirty cats) and has not been reported in the USA.
At present no Recessive White cat, or cat with Recessive White parents or grandparents, can be registered. It has been suggested that these cats should be registered so that their presence in a pedigree shall be obvious.
The cats we have discussed are all recognized in Britain by the Governing Council of the Cat Fancy and, indeed specimens of all varieties named are to be seen at the National Cat Show at Olympia, London. It is quite likely that different colours of some of these varieties are being, or have been produced, but for which no standard has yet been approved by the Governing Council of the Cat Fancy.