A NEW CAT COLOR IS DEFYING GENETIC EXPECTATIONS

Source: Popular Mechanics (Extract)
Posted: May 24, 2024

From roots to tips, this fur tells a tale of evolutionary wonder.

You may be familiar with spooky black cats, playful orange cats, and elegant tuxedo cats. If you’re a cat enthusiast, you might even know about lesser-known color variations like seal point and ticked tabby. But now, there’s a new cat color making waves — salmiak, also known as ‘salty liquorice.’

The striking black, white, and grey hue — christened after a beloved snack in Finland, where this particular fur color has gained attention — owes its appearance to a peculiar phenomenon. Each fur strand begins as black near the root but gradually lightens towards the tip. This distinctive coat pattern was initially observed in 2007. Subsequently, in 2019, it captured the interest of a team of cat specialists led by feline geneticist Heidi Anderson. Since then, the group has been diligently investigating the underlying cause of this unique shade. Recently, they achieved a breakthrough. A research paper detailing their findings has been published in the journal Animal Genetics.

In delving into the realm of cat colors, or genetic traits in general, researchers typically begin with the obvious and progress outward. Therefore, the team initially hypothesized that this novel variant might be an intriguing manifestation of the ‘dilution’ gene responsible for producing white markings.

From a technical standpoint, cats are typically classified into two colors—black and orange. Any deviation from these hues typically arises from a combination of these base colors, a diluted version of one of them due to the influence of the dilution gene, or a blend of both. Hence, when experts began noticing cats with salt-and-pepper fur, the logical assumption was that these represented a novel expression of the dilution gene in action. By enhancing the white areas in a standard black cat, one could achieve the appearance of salty liquorice.

However, despite exploring various genetic variations that regulate the expression of the dilution gene in coat color, the researchers encountered a dead end. Consequently, they embarked on the next phase—conducting genome sequencing of two of these distinctive felines and scrutinizing the entirety of their genetic data to uncover the underlying cause of these unique coats.

The breakthrough discovery lay in what was absent rather than what was present. “There was a significant sequence gap downstream from the KIT gene,” Anderson explained to New Scientist, referring to a gene recognized for its role in influencing white patterns in animal coats. Remarkably, these cats were found to be lacking a specific DNA segment in close proximity to this gene.