Cats come in a wide variety of colors and patterns. While there are many common cat colors like black, white, orange, and gray tabby, some cat coats have very rare and unique colorations. Understanding the genetics behind feline coat colors can help explain why certain colors are less common in cats.
The genetics of cat coat color
The colors and patterns of cat fur are determined by the melanocytes in their skin, which are cells that produce pigment. Melanocytes contain melanin, which is the pigment that gives skin, fur, feathers, and scales their color. There are two types of melanin:
- Eumelanin – Determines black/brown pigment
- Pheomelanin – Determines red/yellow pigment
Cats typically have both eumelanin and pheomelanin in their skin and fur. The distribution and ratio of these two pigments is what creates the many coat colors and patterns we see in cats. Genes control the activity of melanocytes and the production of melanin pigments. So cat coat colors are inherited genetically.
While there are many genes that control coat color in cats, two of the main ones are:
- Agouti gene – Controls the distribution of black pigment. Variations in this gene lead to tabby patterns, solid colors, and more.
- Orange gene – Controls the production of orange pigment. The orange allele results in orange fur instead of black.
Variations in these and other color genes lead to the many potential feline coat patterns we see from the common tabby to unique colors like tortoiseshell and calico.
Rare and unique cat coat colors
While tabby cats, tuxedo cats, orange cats, and black cats are fairly common, some unusual cat colors arise from genetic mutations that result in unique pigmentation. Here are some of the more rare and distinctive cat coat colors and patterns:
Chocolate
Chocolate cats have a rich brown coat color reminiscent of milk chocolate. This color results from a recessive mutation in the melanocytes that causes them to produce less black pigment overall. When an orange cat also inherits this mutation, it results in a warmer cinnamon or chestnut hue known as cinnamon.
Lilac
The dilute version of chocolate is known as lilac, which is a pale grayish-pinkish tone. It also stems from a mutation causing less overall black pigment production in the fur. Lilac is seen more often combined with other colors like lilac tortoiseshell or lilac-cream.
Cinnamon
As mentioned above, cinnamon coats are the dilute version of orange. So instead of a vivid orange, the cat will have a softer cinnamon shade. The melanocytes in a cinnamon cat produce less orange pigment overall.
Fawn
Fawn is the dilute version of cream. A fawn cat has a delicate warm beige or pale pinkish tone. The cream gene paired with the melanin-reducing gene creates this soft diluted color.
Peach
Another dilute color, peach is a delicate pale cream shade with apricot tones. It results from modifying the intensity of orange through a dilute gene. Peach cats may also be called apricot.
Tan
Tan is a recessive variation of agouti pattern tabbies. Instead of having black stripes like other tabbies, tan cats have a light brown tabby pattern on a pale tan background. It almost resembles cafe au lait.
| Cat Coat Color | Description |
|---|---|
| Chocolate | Rich brown color from reduced black pigment |
| Lilac | Dilute grayish-pink tone, dilute version of chocolate |
| Cinnamon | Soft orange shade from reduced orange pigment |
| Fawn | Pale beige or pink, dilute version of cream |
| Peach | Pale apricot cream color, dilute orange |
| Tan | Light brown tabby stripes on pale tan |
Tortoiseshell
Tortoiseshell cats, also called “torties,” have a brindled coat with large splotches of black, orange, and cream. This unique pattern occurs almost exclusively in female cats. To display tortoiseshell coloring, a cat must have two X chromosomes with the genetic recipe for both black and orange pigments. Male cats with an X and Y chromosome inherit only one coat color gene.
Calico
Calico cats exhibit an even more striking tri-colored pattern of black, orange, and white. The white areas arise from completely unrelated genetics. For a cat to be calico, it requires the tortoiseshell genetic recipe above plus a separate gene for white spotting. Once again, calico occurs primarily in females who inherit two color alleles.
Torbie
A torbie is a tortoiseshell tabby blend. They have the typical black and orange tortoiseshell pattern but with tabby stripes overlayed on the colors. Tabbies exhibit a distinct M-shaped marking on their foreheads, which torbie cats will display in both orange and black.
Dilute calico
Dilute calicos exhibit the same tri-colored patching as a regular calico. However, the black color is changed to gray or blue while the orange becomes cream or peach. This arises from the action of a dilute gene that turns down the intensity of the dark pigment.
Gray
Most people think of gray cats as having black fur that is simply diluted to gray. However, cats actually carry a specific gene for gray fur. So solid gray is its own distinct color. Kittens are born with gray fur and it lightens to silvery-white with age in pets known as silver cats.
Smoke
Smoke cats appear solid in color at first glance. However, their hair shafts are actually white at the roots with just the tips colored in black, gray, orange, etc. This effect is called agouti hairs. The overall impression is a cat whose fur looks lightly “dusted” with color.
| Unique Cat Pattern | Description |
|---|---|
| Tortoiseshell | Patchy black, orange, and cream coat in females |
| Calico | Patches of white, black, and orange in females |
| Torbie | Tortoiseshell pattern with tabby stripes |
| Dilute calico | Calico with gray and cream instead of black and orange |
| Smoke | Fur looks lightly dusted with color on white roots |
Rarest cat colors
Some feline coat colors are exceptionally rare because they require two separate rare mutations to occur together. Here are some of the rarest cat colors seen:
Chocolate tortoiseshell
Chocolate tortoiseshell cats exhibit the typical tortoiseshell patching but in brown and cinnamon rather than black and orange. This means the cat inherited genes for both chocolate and cinnamon coloring at the same time.
Lilac tortoiseshell
The lilac version of tortoiseshell has patching in pale lilac and peach hues. Extremely rare, this color requires inheritance of both the lilac and peach genetics.
Chinchilla
Chinchilla kittens are born pure white but develop a light dusting of black-tipped hairs as smoke cats. However, chinchillas have less color even than smokes, making them nearly purely white. Chinchilla requires two dilute genes to remove almost all color.
Amber
Amber is an extremely diluted version of orange with a light beige tone. Like many other dilute colors, amber requires inheriting two copies of the melanin-reducing gene to create such an extreme reduction in orange pigment.
Caramel
The dilute form of cinnamon, caramel cats have a warm tan hue. Two dilute genes must be inherited alongside the cinnamon gene to produce such an delicate tan color.
Bristol
Bristol cats have black pigment restricted only to certain areas like their ears, tail, and face. Named for Bristol harbor in England, this coat color likely stems from a blood vessel defect that prevents full pigment distribution.
| Rarest Cat Color | Description |
|---|---|
| Chocolate tortoiseshell | Tortoiseshell pattern in brown and cinnamon |
| Lilac tortoiseshell | Tortoiseshell pattern in lilac and peach |
| Chinchilla | Nearly purely white with few black-tipped hairs |
| Amber | Extremely diluted pale version of orange |
| Caramel | Tan tone from dilute cinnamon gene |
| Bristol | Black pigment limited to face, ears, tail, etc. |
Why unique cat colors are rare
Many of the rare and distinctive cat coat colors and patterns arise from genetic mutations. A genetic mutation occurs when a random error occurs during DNA replication. Some mutations have no effect or an unnoticeable effect. But occasionally a mutation disrupts an important gene that controls things like coat color.
Most mutations that affect coat color are recessive, meaning two copies of the gene must be inherited for it to be expressed. The rarity of cats with unusual colors is simply explained by the fact that two separate rare mutations have to be inherited together to change pigment production and distribution in very specific ways.
For example, for a cat to have cinnamon fur, it must inherit two copies of the recessive cinnamon gene mutation. Breeding two solid orange cats together can produce cinnamon kittens if both parents carry a single copy of the gene. But the odds are against two orange cats both carrying the cinnamon mutation unless specifically bred for that trait.
Conclusion
While most domestic cats display common coat patterns like tabby, tortoiseshell, tuxedo, and solid, unusual colors appear less frequently. Dilute versions of colors, extreme versions of dilution, and combinations of multiple dilute genes lead to rare shades like lilac, caramel, amber, and peach. For a cat to exhibit one of these unique colors, it needs to inherit very specific combinations of multiple recessive color and pattern genes.
So if you notice a cat with a coat color unlike those seen on most pets, it is likely the result of inheriting multiple interacting mutations that together create a rare feline hue.
