Chocolate British Shorthairs are one of the less common colours. Discover what makes their genetics so interesting...
Chocolate British Shorthairs are one of the most striking colourways in the British Shorthair repertoire. Their warm, rich coats are very unusual - partly because it is a colour that rarely occurs in non-pedigree cats, and partly because it requires a combination of less common genes in order for a cat to appear as chocolate.
These beautiful cats have the real look of a teddy bear that has come to life. Their round, cobby faces are particularly striking in a warm, rich chocolate.
We have some beautiful chocolate British Shorthair kittens available. Please see our kitten page for more information.
Chocolate British Shorthair genetics
The chocolate gene is actually a colour mutation of the black gene. At some point in history a spontaneous genetic mutation occurred, which altered the black gene by adding warmth and making it appear as chocolate. More recently, a further mutation in the gene produced cinnamon.
In order to be chocolate, the cat must also have at least one copy of the non-dilute gene. Any cat who is chocolate but does not have the non-dilute gene will be lilac. As dilute cats are far more common than non-dilute, we see many more lilac cats than we do chocolate.
So we see two genes at play:
- the chocolate gene, which is recessive
- The non-dilute gene, which is dominant, but far less common than its dilute counterpart
In order to be chocolate a cat must be either homozygous chocolate or chocolate plus cinnamon and then it must also have at least one non-dilute gene.
- Chocolate + chocolate + dilute + dilute = lilac
- Chocolate + chocolate + dilute + non-dilute = chocolate, carrying dilution so kittens could be dilute or non-dilute depending on the other parent
- Chocolate + chocolate + non-dilute + non-dilute = chocolate, not carrying dilution so all kittens will be non-dilute
- As above, but with chocolate + cinnamon in which case offspring could also be cinnamon or fawn, depending on the other genes at play
Chocolate British Shorthairs and rufousing genes
The shade of chocolate is thought to be polygenic: with a complex range of genes affecting how warm the shade of chocolate will be. It is not uncommon to see chocolate kittens that look almost black. The precise reasons for this are not yet known, but it is thought that the warmth of the shade of chocolate depends on a wide range of what are called rufousing genes which affect the warmth or redness of the pigment of the fur. We aim for a lovely warm chocolate colour, but it can take generations of selective breeding to get to that point.
Because of the combination of genes, and the complexity of the polygenic rufousing genes, chocolate British Shorthairs have been notoriously difficult to breed well. This may be part of the reason why we do not see them very often. However, in recent years the beauty of their chocolate coat has been receiving a great deal of appreciation, and they are rapidly growing in popularity.
Chocolate or cinnamon?
Interestingly, we recently had a chocolate British Shorthair kitten arrive who appeared to be neither chocolate, cinnamon, lilac or fawn. We are in discussions with a genetic laboratory who are interested in exploring his genome for the possibility of a new colour mutation. Genetically, the only possible colours we should have been able to get from this litter were chocolate or black. Mum also carries cinnamon, so the kitten might carry cinnamon, but should not actually be cinnamon.
Chocolate British Shorthair patterns
As with all British Shorthair colours, chocolate British Shorthairs can come in every pattern imaginable. That can include:
- chocolate colourpoint
- chocolate silver tabbies
- chocolate golden tabbies
- chocolate bicolours and vans
- chocolate torties and calicos
Discover more colours:
- the high white British Shorthair
We are expert breeders of British Shorthair kittens. We specialise in the more magical and unusual colours and patterns. Chocolate British Shorthairs are one of the colours we can have.