Some cats in central Finland show a rare coat that fades from dark at the base of each hair to white at the tip. Locals noticed it in 2007, and the look later picked up the nickname salmiak, a nod to a salty licorice candy popular there.

Scientists set out to learn whether this look was just a quirky fluke or a trait tied to a specific change in DNA. They ended up finding a clear genetic sign and a story that connects pet cats to basic biology.

What makes salmiak cats different

In 2024, a peer reviewed study traced the salmiak pattern to a missing stretch of DNA about 95,000 bases long located roughly 65,000 bases beyond the KIT gene.

The work was led by Dr. Heidi Anderson of Wisdom Panel in collaboration with researchers at the University of Helsinki.

The pattern does not behave like the common tuxedo or white spotting most people know. Each hair in colored areas starts pigmented at the base and becomes unpigmented at the tip, and the tail often ends in near white.

It shows up on several background colors, including black, blue, brown tabby, and tortoiseshell. The look is present at birth and stays consistent as the cat grows.

Where the gene clue points

KIT helps guide the development and survival of pigment cells called melanocytes, which supply melanin to hair and skin. Changes that alter KIT activity can change where melanocytes end up or how well they function.

In many cats, white or spotted coats are linked to insertions from a feline endogenous retrovirus (FERV1) that sits inside KIT and disrupts normal pigment distribution.

Those insertions help explain both dominant white coats and the classic white spotting pattern.

The white paws seen in Birman cats come from a different change in the KIT gene that breeders can identify with a genetic test.

Salmiak cats do not have any of those known changes, which is why the pattern remained a mystery to researchers for so long.”

Salmiak cats and genetics

The team first genotyped salmiak cats for all known coat variants and saw nothing that explained the unusual white tipping.

They then sequenced the whole genomes of two salmiak cats and spotted the 95 kb deletion downstream of KIT described above.

To check the match, they genotyped 183 Finnish domestic cats.

The team found the deletion was present in all five salmiak cats as two copies, present as a single copy in three non-salmiak cats, and absent in the other 175.

That tight match points to a strong association between the deletion and the salmiak look.

The variant follows autosomal recessive inheritance, so a kitten must receive the salmiak allele from both parents to show the coat. Cats with just one copy are carriers and usually look normal.

What inheritance means for owners

A recessive trait can persist quietly in a population because carriers are hard to spot. That makes the salmiak allele rare, and the study did not find it outside the Finnish domestic cat sample tested.

White spotting in other settings can be linked to hearing issues, especially when large areas lack pigment in the inner ear.

A comprehensive review notes that pigment related deafness is most common in animals with solid white coats and blue eyes, and it is confirmed with a BAER test that measures brain responses to sound.

The salmiak cats in the study did not show signs of deafness, but the authors recommended BAER testing to be sure. That is a sensible step any time a new white pattern is involved.

Salmiak cats vs. other patterns

Two cats from Romania and the United Kingdom showed a similar coat pattern known as karpati, but genetic testing confirmed it was not linked to the salmiak gene.

The karpati look has since been used to create the Transylvanian breed, though the exact genetic cause of the pattern is still unknown.

Salmiak and karpati both look similar to roan coloring seen in other animals, where white and colored hairs are mixed together.

In farm animals like goats, changes near the KIT gene are also known to influence these kinds of patterns, with one study linking them to solid white coats in one breed and white spotting in another.

That cross species echo matters because it points to a regulatory neighborhood near KIT that controls when and where pigment forms. Salmiak adds a feline example to that shared genetic map.

Why this matters beyond cats

Patterns like salmiak help biologists see how small changes in noncoding DNA can shift gene expression without altering the protein itself.

Here, the deletion sits outside the coding part of KIT, yet the effect on hair pigmentation is obvious in the mirror.

They also help vets and breeders make informed choices. As cats with salmiak are noticed and documented, testing can confirm carriers and avoid accidental loss of a rare variant.

“The discovery of the salmiak variant enriches our understanding of feline coat color genetics. This knowledge could also be valuable for breeding efforts, potentially contributing to the preservation of this trait in our feline companions in existing cat breeds,” Dr. Anderson concluded. 

The study is published in Animal Genetics.

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