Could Your Cat's Unique Coat Signal a Hidden Mutation?
A team of scientists reveals a strange, new fur pattern caused by a genetic mutation in Finnish felines. This revelation might hold ominous implications for your pet’s future.
Reviewed by Bark & Whiskers
Join the Bark & Whiskers™ Family
Sign up today for our FREE newsletter, packed with expert advice and insider tips to keep your beloved pet in tip-top shape.
View our Privacy Policy and Terms of Service.
STORY AT-A-GLANCE
- A team of researchers has discovered the genetic mutation responsible for a new coat color pattern in cats in Finland that features hairs that are black at the base and gradually lighten to white at the tip
- Officially named the “salmiak” coat pattern, it only occurs in cats whose parents both carried the mutation
- Cats who appear to be wearing socks, or tuxedos, have piebaldism, another gene mutation that causes unusual patterns of pigmentation
- Piebald patterning is likely the result of a process that occurs before birth involving pigment cells that don't divide often enough to create a monochrome coat
- Other gene mutations influence the appearance of tabby cats, the Norwegian Forest cat, and the Siamese and Burmese breeds
A team of researchers, both geneticists and animal welfare specialists, from the U.K. and U.S. has discovered the genetic mutation responsible for an emerging coat color pattern in Finland felines. They published their findings recently in the journal Animal Genetics.1
New ‘Salmiak’ Coat Pattern
Back in 2007, people in Finland began noticing feral cats with an unusual coat color. The kitties appeared have typical tuxedo coats at first glance, but with a twist — they had hairs that were black at the base and gradually lightened to white at the tip. The coat pattern was dubbed the “Finnish mutation” by people who adopted the cats and brought them home.
The researchers decided to look into the genetic mutation that was responsible for the change. They named the new coat pattern “salmiak” after a popular Finnish licorice and asked the public to voluntarily bring in cats for testing.
Initial tests of the cats showed no mutations known to impact the presence of white fur. So next, the team performed whole genome sequencing for two of the kitties, and “found a mutation at a site near the KIT gene that had previously been associated with several white hair patterns in housecats — they also noted that a span of the sequence was missing downstream.”2
The next step for the researchers was to verify they had found the variant they were looking for. They searched for it in 181 cats and found it in three of them with salmiak coats. All three of the cats had inherited the mutation from both parents. The researchers also found three other cats who possessed the variant but not the salmiak coat and discovered they had inherited the mutation from just one parent.
These findings suggest the team has indeed identified the recessive mutation responsible for development of the new salmiak coat pattern. Looking at this image, the study authors identified the cats as follows:
- Cat (a) is a salmiak solid black cat
- Cat (b) is a salmiak solid blue (diluted black) cat
- Cat (c) on the right is a salmiak brown mackerel tabby with his normal colored brother
- Cat (d) is a salmiak phenotype (not genotyped) on a long-haired solid black cat
- Cat (e) is a salmiak solid black cat
- Cat (f) is a salmiak phenotype (not genotyped) on a tortoiseshell cat
Why Do Some Cats Look as If They’re Wearing Socks?
Some famous cats, for example, Lil Bub, Maru, and Grumpy Cat (RIP), appear to be wearing socks thanks to their adorable white paws. The technical term for those socks (aka mittens, booties, tuxedo) is piebaldism, which is a result of a mutation in the KIT gene mentioned earlier that causes an unusual distribution of the cells (called melanocytes) that give eyes, skin, and hair or fur pigment.
Here’s how kitties with socks come to be, from the online magazine Popular Science:
“When a cat is still an embryo, all of its available melanocytes are bunched up toward its back, where its spinal column will eventually form. As the fetus develops into a mewling kitten, pigment cells spread throughout the developing body.
If the melanocytes are evenly distributed, the cat could have a unicolor coat, like Sabrina the Teenage Witch's all-black cat, Salem, or the all-white Hello Kitty. But in many animals, the cells spread irregularly. That's how you get a cat like Sylvester, who's black from his back to his legs, but white down to his toes.”3
The word "piebald" is a combination of “pie” (from “magpie”), and “bald,” which means a white patch or spot. It refers to the distinctive black-and-white plumage of the magpie. In addition to cats, other animals with piebaldism include horses, dogs, birds, pigs, cattle, and even some snakes.
Piebald Patterns
Cats with piebaldism are found across several different breeds, from American Shorthairs to Turkish Vans. There are several commonly seen piebald patterns, including the following:
- Tuxedo pattern — This is a predominantly black cat with white markings on the chest, tummy, paw, and sometimes the chin and/or nose.
- Mask-and-mantle pattern — A cat with a black back, shoulders, and head, and a white underside.
- Cap and saddle pattern — A cat with black over the top of the head, white shoulders, and a large black patch on the lower back, near the tail.
- Locket pattern — A black cat with one small white patch on the chest or tummy.
- Cow pattern — A predominantly white cat with black spots or patches on the torso.
- Van pattern — A white cat with black markings on the head and tail only.
Other Gene Mutations That Influence Coat Colors
Tabby cat coats — which feature distinctive stripes, dots, lines or swirling patterns and a mark resembling an 'M' on the forehead — are the result of the agouti gene, which programs the distribution of black pigment.4 This same gene is responsible for bay horses with their brown bodies and black manes, tails, ear edges, and lower legs.
The Norwegian Forest cat has two gene mutations affecting the coat. The orange gene on the X chromosome produces a red coat in some kitties, and an alteration on the MC1R gene causes the breed to have one coat color at birth that morphs into a golden or amber color as the cat matures.
The Burmese and Siamese breeds have a form of selective albinism that allows their bodies to suppress melanin production based on temperature.
