White Dane and Coat-Color Genetics
First of all, "white" dogs can be white for a variety of reasons.
White Dobermans are white because they are partial albinos. The trait is recessive (both parents must either be albinos, or be albino carriers.) White Dobes have some photo sensitivity issues (like squinting in light that wouldn't usually make a normally-colored Doberman squint.) Their unpigmented skin is somewhat more prone to sunburn/skin cancers. Their hearing is fine. White Shepherds are white because they have a gene that means they don't produce any black pigment (the same gene that produces the color in Irish Setters, yellow Labradors, Goldens) AND a gene that "washes out" the shade of the brown/red pigments. You can see the range of effect of these genes in the variation in color of Goldens--from almost a mahogany red through a pale cream. The White Shepherds have been selected to be as pale as possible--white. They've got a tendency to have some health and/or temperament issues, but NOT because they're white. Instead because breeding stock has been selected for color alone--not for health or temperament. If you don't deliberately breed FOR a trait, you're highly likely to lose that trait. Both "can't produce black" gene and the "washed out red/brown" genes are recessive.
Great Pyrenees are white because they have the extreme white spotting gene. This series ranges from producing a solidly-colored dog (as in "no white" not as in "all one color"--almost all Dobermans are solidly colored black and tan, no white, for example) to the Mantle pattern, Piebald or Particolor pattern, through the extreme white pattern, which will leave the colored areas, if any, on the ear area, and the rump region. They also have the "can't make black pigment" genes, as well as genes that "wash out" the red/brown pigment. Most Pyr's actually *do* have a colored head, or at least right around the ears, but since it's a pale cream color, the dog appears all white. No health issues associated with whiteness and Pyrs. Extreme white spotting is recessive.
In our Danes, of course, we're dealing with the Merle gene. The Merle gene is dominant. One Merle gene and one "normal" gene grays out all but patches of any black areas on the dog. (The Harle gene then makes color an "all or none" proposition--if the individual fur is going to be gray instead of black, the Harle gene prevents it from being colored at all.) Two copies of the Merle gene completely (or, almost completely) wipe out ALL color. Interesting to note that "merling" affects ONLY areas that would "normally" be black. On a tanpoint dog (Doberman-colored), the black areas are merled, while the tan areas remain normally and fully pigments (I've got photos of a mixed-breed dog this pattern, if anyone's interested, although perusing Aussie sites online will show the same pattern, usually with addition of the white-paws-tail-tip-neck-chest.
So, MOST white dogs are produced by doubling up on a recessive gene. Only white Danes are white due to a incompletely DOMINANT gene. No generalizations can be made about "recessive whites" because there are several forms of recessive whites--most or all of which cannot occur in Great Danes. All or almost all White Danes are "dominant whites."
The "can't produce black" gene affects ONLY fur, not nose leather, eye rims, skin. The "washes out red/brown" gene also affects only fur, nothing else. Both the white spotting genes and the Merle gene can affect everything--fur, skin, eye rims, nose leather. Thus, either of these genes can cause a dog to have deafness and/or vision problems if they are so white as to be "white on the inside, too." Lack of pigment in certain inner ear and eye structures lead to a lack of function. In vision, it's variable in effect--sometimes merling will produce an perfectly sighted, but blue (rather than brown) eye. Sometimes deeper structure are affected, the pupils look a bit strange, and there is some visual impairment.
As far as immune systems go--with the dozens of dogs I've fostered over the years, I've seen no more immune system problems in the white Danes than in the general population. I've found I can almost predict the dogs that are likely to have immune system issues by their conformation. Those that look like "good" Great Danes tend to be healthy. Those that look like they're perhaps "not all Dane" also tend to be healthy. Those that look like "all Dane, but a crappy Dane at that" tend to be the ones that exhibit immune system problems. These "middle quality of appearance" Danes are the ones with entropian, mange (demodectic and/or sarcoptic), the ones that break with kennel cough after they've been through a shelter.
I had two deaf Danes come through Rescue, from the same breeder/same litter. A Harlequin to Harlequin breeding, of course. Both dogs were white. Both dogs were deaf. Both dogs were beautiful Great Danes, and both were healthy as healthy can be. One of them was in foster care when I had kennel cough here (from a pair of shelter-Dobermans), and she was one of the few dogs in that room that *didn't* get kennel cough, not even mildly!
Sandy Suarez's Danes are another example--clearly not too far removed from really nice stock, beautiful heads, conformation, and no immune system issues AT ALL.
So, other than the deafness and possible vision issues (which are both "lack of pigment on the inside" problems), I don't see the White Danes being any less (or more) healthy than "normally colored" Danes from the same "level" of breeding stock.
All that said, I would *love* to see the GDCA speak out against Harlequin to Harlequin breeding--because this is the only breeding of "showable" colors in Danes that can or will produce Whites. (Of course, I'd love to see Merles shown, because I find the merle pattern incredibly striking and beautiful, but, should that happen, I'd also like to see a prohibition on Merle X Merle and Merle X Harle breedings.) So, I believe that breedings should be planned so as to avoid producing White Danes. But I also don't see the White Danes as being any less robust and healthy overall as any other color of Dane (the pigment-related deafness aside).
What I hate especially is people who want to claim that Merles themselves are unhealthy (simply NOT TRUE--and this rumor persists almost exclusively among Dane-people, NOT in any of the other breeds with Merle in the gene pool), and that these same people who say such things about Merles, seem to somehow think that Harlequins are different. Harlequins ARE Merles, first and foremost, with an EXTRA "whitening" gene thrown into the mix. In terms of "lack of pigment" problems, Harles will be MORE prone to them than Merles (but less than Whites.)
As a final, somewhat-related, comment....I've only fostered ONE Great Dane that learned as fast as a Doberman (Dobes are SMART--too smart, in many cases, but overall Dobes are the smartest dogs I've worked with [and no, Danes are NOT the stupidest--I own a Bloodhound!]) This one dog (well, bitch, actually) picked up on everything I ever tried to teach her as fast as I could show her what I wanted. Took ONE 5-minute session to teach her to speak on command. I taught her one night. Proofed it the next night. Didn't have much training time for a few days, and then she got adopted. When she was returned to Rescue over 6 months later, she STILL could speak on command for me, with no hesitation or confusion.
Feathers was a deaf White Dane.
Author: Ana Greavu-Rachow