The Oriental Shorthair is a breed of domestic cat, combining the Siamese body type with a diversity of coat colors and patterns. The breed is recognized as such (since 1977) by the United States-based but internationally open Cat Fanciers' Association and (since 1997) the United Kingdom-based Governing Council of the Cat Fancy (GCCF), and various other cat breeding organizations. While the breed's genetic roots are ultimately in Thailand, the breed was formally developed principally in the US. The breed is among the most popular among CFA members.
According to the CFA breed profile, "Orientals represent a diverse group of cats that have their foundation in the Siamese breed." The Siamese, in both pointed and solid colors, was imported to the UK from Siam (today, Thailand) in the later half of the 1800s, and from there spread widely, becoming one of the most popular breeds. The gene that causes the color to be restricted to the points is a recessive gene; therefore, the general population of the cats of Siam were largely self-colored (solid). When the cats from Siam were bred, the pointed cats were eventually registered as Siamese, while the others were referred to as "non-blue eyed Siamese" or "foreign shorthair". Other breeds that were developed from the landrace cats of Thailand include the Havana Brown (which some breed registries classify as simply an Oriental Shorthair variant) and the Korat.
The Oriental Shorthair is a member of the Siamese family of breeds, and can be found in various solid colors, and patterns such as smoke, shaded, parti-color/tortoiseshell,tabby and bicolor (any of the above, with white). Not all variants are acceptable to all organizations that recognize the breed.
Conforming Oriental Shorthairs, like any of the Siamese type, have almond-shaped eyes and a wedge-shaped head with large ears that fit in the wedge of the head. Their bodies are typically "sleek" but muscular.
The long-haired version of the breed, the Oriental Longhair (recognized since 1995 by CFA), simply carries a pair of the recessive long hair genes.