Main Genes of Domestic Cats

Every living entity has genes carried on chromosomes as a pattern for life and evolution.  Breeders work to enhance certain characteristics within their breed and strive to eliminate others with the goal of creating happy, healthy cats that meet the standard for their respective breeds.  Consequently, breeders need to know what the various genes contribute, their interaction with each other and the likely outcome of each.

Symbol Name Characteristics Symbol Name Characteristics
A Agouti Agouti ground color of tabby; hairs banded yellow/orange a Non-agouti Hairs not banded; unicolored (acts only on black/brown)
Black Black pigment b



Light brown

Dark brown (chocolate or chestnut) pigment

Medium brown (cinnamon) pigment

Full color Maximum pigmentation cb






Blue-eyed Albino


Dark sepia-brown pigment

Light sepia-brown pigment; dark points; blue irises

White coat; pale blue irises

White coat; unpigmented (pink) irises

Dense Dense pigmentation d Dilute Dilute pigmentation (eg black to blue)
Normal ears Normal (pricked) ears Fd Folded ear Folded ears; crippling when homozygous
Normal coat Full coat of normal density hr Hairless Total or almost total lack of hair on the body
i Normal pigmentation Full development of  pigmentation I Inhibitor Suppresion of pigmentation from parts of hairs
L Normal hair Short hair l Longhair Hair longer than normal
m Normal tail No shortening of the tail M Manx Tail shortened or missing; lethal when homozygous
o Normal color Normal pigmentation (not orange) O Orange All pigment turned to yellow/orange (sex-linked)
pd Normal toes Normal number of toes Pd Polydactyly Extra toes, especially on the front paws (variable)
R Normal coat Straight hairs of normal length and type r Cornish Rex Hair shorter than normal; curled, no guard hairs
Re Normal coat Straight hairs of normal length and type re Devon Rex Hair shorter than normal; curled.
Ro Normal coat Straight hairs of normal length and type ro Oregon Rex Hair shorter than normal; curled, no guard hairs
s Normal color No white spotting S Piebald White spotting or patches; variable expression
T Mackerel Striped tabby pattern Ta
Abyssinian Tabby pattern
Blotched (classic) tabby pattern
w Normal color Full expression of all other color genes W Dominant white White coat; blue, orange or odd-eyed irises; masks all other colors; in combination with blue eyes may show deafness.
wh Normal coat Straight hairs of normal quality Wh Wirehair Hair excessively undulated and wiry to the touch