A white colour occurs due to a lack of pigment in the hair follicle. As such, the cat appears white. However, white acts as a paint, meaning that the cats true genetic colouring does not match its appearance. So, even though your cat appears white, it’s genetic colouring could be a brown tabby.
White Spotting Gene
The white spotting gene is the main causative agent for a cat that is partially or wholly white.
The naming for your cats colour is dependant on how much white covers the cats body. A mitted cat is when there is white solely on the cats paws. This can range from only one paw to all four.
An “and white” cat is when up to 35% of their body has white on it. For example, a Red and white kitten. When the body has between 36-60% of it covered in white, this is known as a bi/tricolour. A bicolour occurs in cats when they are only one colour, for example, a silver bicolour would have a silver coat colour with up to 60% of the coat covered in white. A tricolour occurs when you have a tortie colouring along with the large amount of white.
“And white”
Bicolour/tricolour
Full White
When a cat’s coat contains more than 60% white, it is considered “white”.
Eye Colour Associated with White Coat
Because the white colour is due to a lack of pigmentation, the lack of pigmentation can also transfer to the eyes. When a cat has a lack of pigmentation in the eye, this is when you get blue eyes.
A white cat can have any colour of eyes, which is dependent on the parents eye colour, as well as the possible lack of pigmentation. White cats are also unique as they can produce heterochromia (odd eyes)
Odd eyes occur when one eye is affected by the lack of pigmentation from the white spotting gene while the other is unaffected and is passed down normally from the parents.
Concerns with White Coat
White coat colour can be associated with deafness in cats. When the lack of pigmentation affects both eyes (i.e., two blue eyes), there is a chance it can also impair hearing in the cat.