A rex cat is any of a number of different domestic cat breeds, distinguished by wavy or curly fur, which may be long or short, light or thick. The breeds originate from naturally occurring genetic mutations, which have since been selectively bred. There are four main internationally recognised rex breeds:
- Cornish Rex
- Devon Rex
- Selkirk Rex
There are also a number of rarer, less well known or developing rex-coated breeds, including the German Rex, Ural Rex, Tennessee Rex, Tasman Rex group and Skookum. Spontaneous rexed variants have also been observed in breeds such as the Maine Coon and Persian as well as in random-bred cats such as the Ohio Rex, Oregon Rex and California Rex, however there has been no significant attempt to develop or seek recognition for these varieties and most have died out. A number of experimental breeds have been developed from the main 4 rex breeds, such as the German-bred Pudelkatze (Poodle Cat), now believed to be extinct.
Rex breeds vary considerably in appearance, from the elegant slender build of the Cornish Rex to the larger, cobby and heavy-boned Selkirk Rex. Each results from a separate mutation rather than being bred from a common ancestor. Each mutation causes the hair follicles to be oval in shape, instead of the normal regular round form, which results in hairs curling round as they grow instead of growing straight. Many of the other spontaneously occurring rex mutations have occurred and some have proven to be the same gene as the main four breeds. Some of those mutations, such as the Dutch Rex, were found to have unmanageable or unattractive fur and were not pursued as breeds.
The name Rex was taken from the Rabbit Fancy because the first rex cat breed to be developed, the Cornish Rex, has a coat similar to that of a rex rabbit, in that it comprises only the undercoat with no topcoat or guard hairs.