Why Does a Siamese Cat Turn Black?

1 Why Siamese Cats Turn Black

The Cause of Darkening

Many mammals carry a gene called TYR, which regulates the production of tyrosinase. This enzyme, present in animal cells, promotes melanin synthesis. The higher the tyrosinase activity, the faster and greater the melanin production. Siamese cats also express this gene, and its form can mutate with time and environment; when TYR mutates, it causes errors in protein synthesis and produces different traits.

Moreover, the mutation in the Siamese melanin gene means the tyrosinase it produces has a fixed defect and cannot work normally at body temperature. Notably, when the temperature under the skin drops below 30C, this gene form becomes more active and expresses more strongly.

Does Shaving Cause Darkening?

Shaving is not the main reason new fur turns dark; it only speeds up the process. Whether the coat darkens mainly depends on the surrounding temperature. When a Siamese cat’s skin drops below 30C, the tyrosinase in its cells becomes more active, and this change directly affects melanin synthesis and distribution. So shaving accelerates melanin production and darkens the fur.

How to Prevent Darkening

Because darkening is mainly caused by low temperature, if you do not want your Siamese cat to get darker, keep it warm as the weather changes, especially the face, which can turn fully dark as temperatures keep falling.

However, the coat will gradually lighten again as temperatures rise; living in a warm environment usually restores the cat’s usual color.

Tip: learn about this gene before getting a Siamese cat, so you are not surprised, or put off, when its fur darkens.