Some tabby coats have some white fur, usually on the paws, belly, chest, throat and sometimes face. The dilute modifier only affects dilute colours and does not affect dense colours. Red based colours have two alleles that are located on the X chromosome.ĭilute coat colours are a recessive trait that dilutes coat colours by causing uneven distribution of pigment in the hair shaftĪ secondary type of dilution known as dilute modifier can also occur, which causes the coat to take on a brownish cast. b1 which further reduces melanin density to a medium brown (cinnamon).b reduces melanin density to a chocolate colour.The black gene has three alleles that control the density of eumelanin in the hair shaft. Eumelanin is spherical and absorbs almost all light, which gives black pigmentation, pheomelanin granules are elongated and produce the red coat colour. Cats have two types of melanin, black-based eumelanin and orange-based pheomelanin. The size, shape and arrangement of melanin granules are responsible for the colour of the cat’s coat. Melanocytes are cells responsible for producing melanin, which are microscopic granules occurring in the hair, skin, and iris of the eyes. But a dilution can change those primary colours into lighter forms. The tabby coat occurs in many colours, primarily silver, brown and red ( ginger/yellow). For this to occur, the DNA has to be converted into messages which can be used to produce proteins, which are complex molecules that do most of the work within the cat’s body.Ī locus (plural loci) is the specific, fixed position on a chromosome where a particular gene or genetic marker is located.Īlleles are variants of the same gene, for example, B (black), b (chocolate) and b1 (cinnamon). DNA contains the instructions necessary for the cat to develop, survive and reproduce.

Genes are contained within the chromosome which is made up of a double-strand helix containing DNA. If an X sperm fertilises the egg, the offspring will be female (XX), if a Y sperm fertilises the egg, the offspring will be male (XY). All of the female cat’s eggs are X, whereas the male sperm can be X or Y. 18 of the chromosomes are autosomes, and one pair is the sex chromosomes X and Y. Basic cat geneticsĬats have 19 chromosomes which come in pairs, one from the mother and one from the father. The basic wild-type tabby is a mackerel ( T m) however, two mutations have arisen, the dominant ticked tabby ( T a) and the recessive classic tabby ( t b). Some young cats with solid coat colours will display faint ghost tabby markings until their fur becomes fully pigmented. Even cats with no tabby stripes have tabby genes but do not show the pattern on the fur. All domestic cats were once tabby, mutations lead to some cats appearing solid, bi-colour or pointed. Tabby patterns are common in random-bred cats as well as many pure breeds.

a/a (heterozygous recessive) – Non-tabby (solid).

A/a (heterozygous dominant) – Tabby (the dominant A will override the recessive a).

Three possible outcomes dictate if the coat will be tabby or not, remembering that the cat receives a copy of each gene from the mother and the father. A cat must receive two copies of the recessive ‘ a’ gene (aa) to have a solid coat.

The recessive a hides the tabby pattern, to produce a solid (self) coat colour from the root of the hair to the tip. The dominant agouti allele, with the symbol A, will express the tabby pattern. The agouti gene controls whether the tabby markings are expressed or not. This is caused by the transient inhibition of pigment production during, the hair’s growth. The banded background (ground colour) consists of hairs that are more than one colour along the hair shaft and is termed agouti. Tabby refers to a coat pattern in cats that consists of dark swirls, stripes, spots superimposed on a lighter background of ticked (banded fur). What colour is a tabby cat? Tabby occurs in several colours, the most common are brown tabby, silver (grey) and orange tabby.The background hair consists of light and dark bands, intermingled with dark lines, spots or swirls layered on top. What is a tabby cat? Tabby is a coat pattern and not a breed, it consists of four patterns, mackerel, spotted, classic and ticked.

Mackerel tabby cat with white paws