Some white cats suffer from inherited deafness, but this is not always the case. In those that are afflicted, deafness is the result of degeneration of the inner ear's auditory apparatus. It can be bilateral, affecting both ears, or unilateral, affecting one ear only.
Deafness in white cats is generally found only in white cats with blue eyes. A gene has been identified that is responsible for the condition, and it is the same gene that causes the eyes to be blue and the coat to be white. Of the total cat population, only 5 percent have white coats, and only 1 to 2 percent of the population has one or both blue eyes. Of those with two blue eyes, around 60 to 80 percent are deaf.