For convenience, breeders talk of Wide Band as a single gene, but there appear to be multiple interacting genes that determine the width of the pale band between the pigmented tip and the follicle. In addition to the dominant Inhibitor gene (not present in the Golden series), a good quality silver cat also has a separately inherited “Wide Band” effect.
#Blue silver tabby cat series
The introduction (or re-introduction) of the red series also introduced tortoiseshells. "Cameo" described the type of red - similar to the colour of old cameo necklaces - with "Cream Cameo" (pictured here) simply meaning a paler form of this. In red-based colours, the term "shell" was used to describe the cat having a shell of colour rather than a solid (to-the-roots) colour. The naming convention is given in the table below. It can occur in any of the black-based and red-based colours and in tortoiseshell and tortoiseshell-tabby. Tarnishing is common on the muzzles of random bred silver tabbies, but rare on pedigree silver tabbies due to selective breeding and refinement. Sometimes the Inhibitor gene fails to completely block pigment (it is more effective at blocking black-based pigment than blocking red-based pigment) and there is a breakthrough of reddish colour known as "tarnishing". Shading and silver also occurs in reds and creams which are sometimes termed cameos. These patterns are most striking on the eumelanistic colours (black, blue, chocolate, cinnamon, lilac), because of the contrast between pattern/top-colour and the background/undercolour. The width of the light band is influenced by polygenes, collectively called "wide band." The tipping colour is known as the top-colour, while the pale colour of the hair shaft is known as the undercolour.
Tipping/shading causes the normally yellow-brown agouti band to be both lighter in colour and wider, starting closer to the root and ending nearer the hair tip than in tabby cats. This gene allows pigment at the tip of the hair, but restricts the amount laid down on the hair shaft, so that the shaft is either white/ivory (silver series) or golden (golden series). Smoke, shaded and tipped patterns are due to the Inhibitor gene (silver-restriction). Mackerel (Mc) is dominant over blotched (mc). Ticked tabby (Ta) is on one allele while the tabby patterns are on a different allele. There are three identified alleles of the tabby gene. In cats with the Agouti version (allele), the actual pattern is due to a different gene. The recessive form, non-agouti "a", means the hair is solid colour without lighter bands. The agouti gene, A, allows the hairs to be banded with alternate light and dark bands.
Tabby patterns are cause by genes at two different places. The second section explains the genetics, including disproved theories you may come across elsewhere (even disproved theories come back to haunt breeders!).įirst some very basic genetics! The difference between chinchilla/tipped, shaded silver and silver tabby are largely due to the underlying tabby pattern (ticked, mackerel/spotted or classic). The first section explains the different patterns and a little of their history. There are many terms used to describe the different smoke, shaded and tipped cats and these are different depending on whether a cat is longhaired or shorthaired! Some terms are now only found in older books, so I've included the various alternative names. This article looks at the history and genetics of the silver and golden cats. INHIBITOR GENE: SILVER AND GOLD: SMOKE, SHADED AND TIPPED CATS
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