Colour Variants in Siberian Cats: A Comprehensive Review of Phenotype, Genetics, and Breed Registry Standards.

Siberian cats are characterized by a high level of genetic variability, which is also reflected in a wide range of colour variations. Knowledge about the genetic background of these coat colour varieties is fragmented and predominantly derived from research on other breeds, with inconsistencies in nomenclature across major feline organizations. This review aims to offer a comprehensive synthesis of the genetic mechanisms underlying coat colour and pattern variation in Siberian cats, while also critically examining how these phenotypes are defined, named, and recognized across key international feline breed registries. In Siberian cats, as in other breeds, the fundamental factor in the development of a phenotype is the interaction of multiple genes involved in the production of various types of melanin, its quantity, and distribution in the skin and coat. An analysis of breed standards revealed inaccuracies in the naming of several traits and differences in the acceptance of certain phenotypes within the breed, most notably concerning basic colours, ticked patterns, colourpoint recognition, silver and golden variants, as well as definitions of white spotting categories. The Siberian cat exhibits complex and partially breed-specific genetic determinants of coat colouration. Unification of nomenclature among feline federations would improve clarity in breeding practice and genetic documentation. Some of the traits still require molecular research into their genetic background, making the breed interesting not only to cat lovers but also to researchers.