No, white Danes are not rare. No, not all white Danes are deaf. No, not all white Danes have eye problems. White Danes are produced from doubling up on the Merling gene, as happens in Harlequin x Harlequin breeding, Harlequin x Merle breeding or Merle x Merle breeding. The same potential problems and issues arise with this double merling not only in Great Danes, but in Aussies, Collies, ANY breed that has Merle or Harlequin. Hopefully, bringing the Mantle into acceptance in the GDCA can help reduce the number of deaf Danes out there. By broadening the number of finished (AKC Champion) Danes in the entire Harlequin gene pool, more breeders can make an educated choice of a non-Harlequin mate for their Harlequins.
Not that there's anything wrong with a deaf Dane! The training is mostly a matter of learning to communicate with your hands instead of your voice. And because body language is even more important to a dog than verbal cues, this body/hand signal training can actually occur faster than training a hearing dog with verbal signals!
So what do you do if they're deaf and have eye problems?! Santana says that's a good question! Santana is deaf and has very limited vision due to Micro-opthalmia. He had surgery to amputate his third eyelids to give him a little sight. He has little tiny eyeballs, set way back in the sockets. Surprisingly enough, he was pretty easy to train. He came to us with a lot of socialization skills thanks to Dale Bath at Harlequin Haven. He loves people and kids and responds very acutely to touch. This dog will be the first (well, after his blind buddy Beau) to take you on a trip through the back woods, or into the pond. Scared is not a part of his vocabulary. The neighbor kids love to play hide and seek with both blind Danes. I "cover" their eyes, the kids hide and Beau and Santana find them by air-scenting and tracking in a matter of seconds.
But what about all the "health problems" with those white Danes? The immune system problems, the aggressive tendencies, the brain abnormalities, skin disorders, etc. If you read the "facts", you will soon find out that most of it is based on anecdotal experience. The fact is, outside of the potential deafness and eye problems, there isn't any research or evidence that any of the aforementioned has any truth to it. The problem lies with the pigmentation cells not making it to where are supposed to and the inner ear and retinas do not form as a result.* That's it. The rest is all about socialization, and training.
I think you'd be amazed at what dogs with challenges, can accomplish. For example, Alexandra and Beau have had careers in therapy work with kids, and clients at nursing homes. All of them have been involved in representing the Great Dane breed and also rescue, at many of our events. Many of them are also involved in acclimating new foster Danes into the program. In fact, you won't find a better foster mom than Beau - he loves that job!
Now, if you are buying a Harlequin puppy from a breeder, ask about the hearing and sight status. It does occasionally happen where a less-than-ethical breeder sells a Dane not informing the buyer that the pup may be deaf/sight challenged. If you are planning to adopt a deaf pup or older dog, make sure you realize the time and training it will take. You must have patience and you must have the basic skills to train the dog effectively. Do not adopt a deaf/sight challenged pup as a novelty - the novelty will wear off.