Colordilution

Colordilution is a genetic trait found in some animal species, most notably horses and dogs, that affects the expression of pigment in the coat. This trait results in a lighter, more muted version of the base coat color. For example, a black coat with colordilution might appear as a smoky black or a dark grey, while a chestnut coat could become a lighter shade known as a flaxen liver.

The mechanism behind colordilution involves a dilution gene that interferes with the distribution of pigment granules within the hair shaft. Instead of being densely packed, the pigment is clumped together in smaller clusters, which affects how light reflects off the hair, creating the appearance of a lighter color. The gene responsible for colordilution is typically recessive, meaning an animal must inherit two copies of the dilution gene to exhibit the diluted coat color.

Different breeds exhibit colordilution in varying degrees and with different names. In horses, common diluted colors include buckskin (diluted bay), palomino (diluted chestnut), and cremello (diluted chestnut with two cream genes). In dogs, breeds like the Weimaraner and the Australian Cattle Dog display diluted black or red coats, often referred to as "blue" or "red dilution" respectively. This trait can also interact with other genes to create a wide array of fascinating coat patterns and shades.