It's called heterochromia and it can happen to other species, including our own.
As far as Cats are concerned : That is called to be "wall-eyed". That's a genetic defect associated with fur, manyoya color and eye color : white Cats are deaf on the side of their blue eye. If the cat has its both eyes blue, it is 100% deaf.
Beware, they are deaf if they are white. It's a genetic defect in conjunction with white fur. I also had blue eyed Cats (Siamese) and of course they were not deaf.
yes . my friend who is also on shabiki pop called oshey hase 1 her name is oshey 1 eye is ocean blue and 1 is hazel thats y my friend kept the name ^^ but she dosent like me so this pic isnt very clear but this is all iv got .