Why does the coat color of Siamese cats change?

The coat color of Siamese cats changes with temperature and age. The lower the temperature, the darker the color of Siamese cats. The higher the temperature, the whiter (lighter) the color. So cats are usually white when they are born, but Siam will start to turn black when they grow up. Why does the coat color of Siamese cats change? The coat color of Siamese cats changes with temperature and age. The lower the temperature, the darker the color of Siamese cats. The higher the temperature, the whiter (lighter) the color. So cats are usually white when they are born, but Siam will start to turn black when they grow up.

According to research, there is a gene called TYR in most mammals, which is responsible for regulating the synthesis of tyrosinase, which exists in cells and can promote the synthesis of melanin and the localization and distribution of pigment. This means that the higher the activity of tyrosinase, the faster and more melanin is synthesized. This genotype is also expressed in Siamese cats, and some mutations will occur with the change of time and environment, that is to say, TYR in Siamese cats is mutated, so that protein synthesis is wrong, thus showing different characters.

When this gene is changed, the synthesized tyrosinase also has irreversible defects, so it can't play its normal role at normal body temperature. Especially when the skin temperature is lower than 30 degrees Celsius, its activity will increase and its expression will be more active. Siamese cats are generally white when they are born, because the uterus is warm. With the growth, the coat color will change from all white to light brown, and then the coat color will begin to darken in the lower temperature parts such as nose, ears, tail and limbs. Some siamese cats have their whole faces dyed dark brown with pigment, while the parts with higher body temperature remain light brown or grayish white.