Exactly what does it mean by "lethal" white? Is that because they could be blind and deaf, or they have a high death rate? I've seen this written here a few times, but I'm not sure what it refers to.

The dane is gorgeous, I hope she/he can see and hear. The collie/sheltie that was pure white with no eyes.. how sad! You'd think people would want to breed for health. Thank god there are people out there who will love and take care of animals born with such disabilities.