Why are white blue-eyed cats deaf? - briefly
White blue-eyed cats are often deaf due to a genetic link between coat color and hearing. Specifically, the gene responsible for the white coat is dominant and can affect the development of the inner ear, leading to deafness in some cases.
Why are white blue-eyed cats deaf? - in detail
White, blue-eyed cats are often associated with deafness due to a specific genetic condition known as Waardenburg syndrome. This syndrome is characterized by a lack of melanin production in various parts of the body, including the skin, hair, and inner ear. Melanin plays a crucial role in the development and function of the cochlea, which is responsible for transmitting sound signals to the brain. In cats with Waardenburg syndrome, the absence or reduction of melanin in the inner ear can lead to malformations that impair hearing.
The genetic basis for this condition lies in a mutation called the KIT gene. This gene regulates the development and migration of melanocytes, which are cells responsible for producing melanin. In cats with Waardenburg syndrome, the KIT gene is often mutated or deleted, leading to an absence or reduction in functional melanocytes. As a result, these cats may exhibit characteristic white patches on their coat, often accompanied by blue eyes, due to the lack of pigmentation.
The correlation between deafness and Waardenburg syndrome in white, blue-eyed cats is well-documented. Studies have shown that a significant proportion of these cats are either unilaterally or bilaterally deaf. The exact percentage can vary, but it is generally accepted that the risk of deafness is higher in cats with this specific coat color and eye color combination.
In conclusion, the deafness observed in white, blue-eyed cats is primarily due to Waardenburg syndrome, a genetic condition that affects melanin production. The absence or reduction of melanin in the inner ear can lead to structural abnormalities that impair hearing, resulting in deafness.