• CFA states that tabby is a pattern and not a breed, and that the same is true of calico and tortoiseshell.
  • CFA's written breed standards define the forehead marking in both main patterns: classic tabby frown marks form an intricate letter M, and the mackerel tabby head is barred with an M on the forehead.
  • Tabby hairs come in two kinds. The stripes are made of solid colored hairs, while the fur between them is banded with alternating pheomelanin and eumelanin, which is what the word agouti describes.
  • The Tabby locus, the gene laeverin, decides whether a patterned cat is mackerel or classic; a separate dominant Ticked locus, with DKK4 implicated, removes body pattern altogether as in the Abyssinian.
  • Solid colored cats carry tabby genotypes too. Melanism in cats traces to a two base pair deletion in ASIP, which masks the pattern rather than deleting it, and ghost markings can still show through.

What to look at

  1. The forehead. Both main tabby patterns put an M on the forehead, written into CFA's standards as frown marks forming an intricate letter M in the classic pattern and a barred head with an M in the mackerel pattern.
  2. The line from the eye. CFA's classic and mackerel descriptions both call for an unbroken line running back from the outer corner of the eye.
  3. The body markings, which name the type. Narrow vertical pencillings around the body are mackerel. Broad swirls with a large solid blotch on each side encircled by rings are classic. Discrete spots are spotted. No body pattern at all, on banded hairs, is ticked.
  4. The legs and tail. Both patterned types carry barred legs and a ringed or barred tail, which often survive in a cat whose body pattern is faint.
  5. The background fur. Part the coat between the stripes and look at a single hair. Alternating light and dark bands along the shaft mean agouti, and that is what makes the ground color look warm rather than flat.
  6. Necklaces on the neck and chest, described in CFA's standards as several unbroken necklaces in the classic pattern and distinct chain like necklaces in the mackerel pattern.

Four patterns, at least two genes

The old model gave one Tabby locus three alleles. The current picture, set out in Animal Genetics in 2021, uses at least two loci. The Tabby locus is the gene laeverin, and it decides whether a patterned cat comes out mackerel or classic. A second locus, Ticked, is dominant and epistatic to it: a cat carrying the ticked allele has banded agouti hairs across the body and no stripes, swirls or spots at all, which is the Abyssinian and Singapura look. Two variants in DKK4 are the current candidates for that allele. The spotted pattern of the Egyptian Mau and Ocicat is still not pinned to a named gene, and the same paper says so.

Every cat is a tabby underneath

Tabby is the ancestral state, and solid color is the thing layered on top. Melanism in the domestic cat traces to a two base pair deletion in ASIP, the agouti signaling protein gene, which removes the banded hair and leaves the cat solid. The pattern genotype underneath is untouched. That is why a black cat in strong sunlight often shows ghost stripes, and why the 2021 Animal Genetics work notes that ghost or bleed through tabby patterns appear in cats carrying the temperature sensitive tyrosinase variants, in dilute cats, and in orange cats. CFA's own advice to breeders makes the same point from the other direction: blue kittens may carry tabby markings that usually fade as the adult coat comes in.

What a photo can and cannot tell you

A photo is good at tabby. The M, the eye line, the necklaces, the leg bars and the shape of the body markings are all surface features, and a daylight photo of a cat standing side on usually names the tabby type without argument. A close crop of the flank will even show whether individual hairs are banded. What the photo cannot do is turn the pattern into a breed, because tabby is not one. A tabby coat sits on pedigreed Maine Coons, Bengals and Orientals and on a very large number of unregistered cats, and nothing in the markings distinguishes those cases.

Related guides

Sources