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NOTE THE INCLUSION OF THIS ARTICLE AT INDIVIDUAL BREEDER WEBSITES IS UNAUTHORIZED & THE DISCUSSION OF COLOR & MARKINGS BELOW NO WAY SUGGESTS A SUPPORT OF INDIVIDUAL BREEDER PRACTICES OUTSIDE OF BREED TRADITION.. ALL THOSE WISHING TO PURCHASE A GREAT DANE IN THE USA SHOULD BEGIN BY VISITING THE GREAT DANE CLUB OF AMERICA'S WEBSITE.

**NOTE: The articles in the section on "Great Dane SPECIFIC Coat Color Information" are intended specifically as a practical aid to those breeding & exhibiting Great Danes. They may not always be relevant to other breeds & the information is deliberately not technically minded.

WHITES: IS IT WORTH THE RISKS?*

OWNING & BREEDING (in two parts-scroll down).

A. OWNING: White danes are dogs who generally are "at least" deaf & may well suffer from a variety of other congenital & inherited defects associated with lack of pigment, which is not confined to the hair & skin in the white dane, but can cause multiple defects in various structures to include particularly the sensory (nervous) system which develops in close contact with the skin system in early embryo stages. Below is given a list of defects specifically associated with the white merle(MM= homozygous merle=double merle=dominant/defective white) Dane. Piebald coloring with extensive pigment loss can also result in deafness as it quite commonly does in the Dalmation, for example, & a series of articles is listed at this site that discuss the generally unsuccessful attempts to raise & keep safely a deaf dog as a pet. (Danes can carry both piebald white & merle white genes, so are at increased risk for defects over most other "white" dogs, esp. deafness & sight defects.) To see a typical white up close, click here and see below. Dogs being sold as "merlikins" "lightly marked harlequins" "white & blue," "white with markings," "white with blue eyes," etc. are all potentially at risk. A gallery of dogs referred to as whites can be found here: note these dogs mostly all ended up in rescue & ALL of them are said to be deaf. To see all the various things merle can do in various breeds, click here. More white dogs of various breeds, all at least deaf, are posted here: you can see how certain traits are typical for such dogs. For more info on neural crest development see: Neural Crest 1 or Neural Crest 2. For more information on pigmentation defects, CLICK HERE .. For a user-friendly overview about diseases associated with color issues (by a crack geneticist who is also a dog breeder), click here. Also all kinds of whites in Danes have a corollary to the whites in Aussies at this very good explanation on the web. Note this breed health and welfare site discusses the production and problems in whites, and, as it typical, asks for them not to be bred or even reared: http://www.ashgi.org/articles/fact_white.htm

The unemotional fact is that rescue fills up with deaf/sensory defective Danes as most are abandoned by their breeder and/or owner as unsuitable pets. This is not to say they cannot be managed, but it takes an enlighted home, some specialized training, and of course an awareness of the dog's handicaps & health concerns. Many animal welfare organizations endorse humane euthanasia for ALL (bilateral) deaf puppies for the __puppy's__sake, & most white danes are not only deaf, but may have eye & skin problems as well. And there are far, far, too many Danes in rescue already, not to mention far too many pet Danes out there given the (too few in) number of suitable pet homes. It is a GDCA Code of Ethics violation to knowingly sell a defective (unhealthy) pup as a pet, & any harl breeder worthy of the name knows that white pups will usually suffer from a variety of unpleasant problems which may well continue to arise (& surprise) the owner thru the first year or longer. Traditionally the responsible breeder typically culled such pups to ensure they did not burden the pet-owning population, take a home from another pup, or sell a dog who ended up misunderstood or who continued to cost the owner large amounts in medical or training bills. There are some things to think about before condemning breeders who euthanize pups with sensory defects or applauding those who do not. Not a nice life it would seem, is in store for the average deaf and/or blind dane, which is the reason most responsible breeders usually do NOT offer them up as pets but under very rare situations to people, for example, they know well who live nearby and/or know how to train/have experience with deaf dogs. The best sort of breeder isn't going to overlook the potential difficulties in adopting out a sensory-defective puppy, even though they are just as emotionally bonded to their dogs as anyone, and we all wish for a capable home to come along for every potentially deaf/sensory defective puppy (as well as most try to avoid breedings that produce such pups whenever feasible).

So this is not, forgive the pun, a black & white issue. See the list below for the defects associated with White (double merle) Danes. Note many of these are very serious problems, not all of which are obvious to the casual observer at 2-3 months. Recall also that "just" deafness & "just" poor sight are not so minor to a dog, & the lack of proper sensory equipment is for them a hardship indeed. Such dogs benefit from a "helping" (hearing ear) dog to get along day to day, & need an enlighted owner & some specialized training (otherwise deaf dogs get a reputation for an increased bite incidence & auto collision rate). Certainly there are success cases in keeping an otherwise healthy deaf dog, but these success cases are far outnumbered by the failures, although this isn't the fault of the dog necessarily. That said, in today's more able & enlightened training environment, a motivated & caring owner CAN make a deaf dog's life a true success.

IF YOU WANT TO ADOPT A DEAF DANE, CLICK HERE TO READ MORE ON DEAF DOGS.

IF YOU WANT A DEAF WHITE SEE ADOPTION SITES LIKE THIS: DDEAF--DEAF DOG EDUCATION ACTION FUND.

DEFECTS ASSOCIATED WITH WHITE DANES:

1.Congenital CATARACTS associated with micropthalmia. A blinding disorder.

2. Persistent pupillary membrane. Can be blinding, is disfiguring eye defect.

3. Tapetal hypoplasia. Lack of reflective lens. Can cause night blindness.

4. Convergent stabismus. Cross-eyed-affects vision, especially focus, depth perception.

5. Enopthalmia-recessed eyes-can lead to chronic infection.

6. Micropthalmia-tiny eyeyballs--often lead to total blindness & most have very poor sight from the start. Sometimes the eyeball(s) must be removed.

7. Medial canthal syndrome--when (commonly) associated with 5 &/or 6-leads to chronic infection & blindness.

8. Heterochromia iridis/hypochromia iridis-lack of iris pigment-causes blue eyes & is associated with deafness and photophobia, & can be associated with other eye defects in predominately white dogs.

9. Colomboma(ta). "Notched" irises & other eye structures which fail to develop properly & close on the suture lines due to the action of the Merle gene. Can lead to various defects of vision & even collapse of the eye structure.

10.Merle deafness--develops in the first month of life & is permanent & often debilitating to proper social development of the dog. Defined as bilateral; testable by no later than 6 weeks; associated often with other less apparent defects.Most all white Danes are deaf.

11. Piebald deafness--is present normally by 4-8 wks. Can be unilater or bilateral; deafness can only be objectively confirmed by a BAER test. When bilateral, euthanasia is commonly recommended.

12. Demodicosis. Immune-mediated hair follicle mange. Increased incidence in reported in harl-bred danes--esp. in white & merle pups.

13. Atopic dermatitis. Inherited allergies. Increased incidence in reported in harl danes & esp. white & merle pups.

14. Skin cancer. Increased incidence in reported in harl danes & esp. white & lightly marked harl & merlikin pups due to lack of protecting pigment (melanin) from UV (sunray) exposure. Sunburn also occurs often in dogs lacking pigment & this can lead to tumors/cancer.

15. Follicular dysplasia. A haircoat problem of broken & dull hairs & "pimply" infection with a high incidence in white coated (& other dilute colored) dogs.

16. Photo-induced epilepsy. Seizure activity reported in white (double merle) danes thought to be associated with subtle eye structure defects.

17. Sterility & reduced fertility. Increased incidence anectodately reported in some mostly white pups.

18. Multiple congenital defects. White pups may have a variety of organ defects which arise only as they grow & first may only be seen (if seen when young at all) as a (i.e."runt") failure to thrive & keep up with the size, weight & activity level of the other pups, but later result in multiple health problems for the dog. Bear in mind that about 50% of MM=double merle whites do not survive to birth.

19. Social instability & inadequacy. Dogs with sensory defects are often unable to interact with their own species as well as with humans with full & satisfactory success. Such pups may well be identified, isolated & treated as different right from the start by the dam & the other littermates. Many develop poorly, fail to adapt & have multiple problems coping with normal daily actitivies; they are often described as "shy" or "'spooky" & the bite incidence for such animals is high. Some are picked on, most have trouble with normal events, esp. those involving more than the immediate family (the vet, boarding, etc.), while others need another pet constantly with them to cope with the world at large & suffer tremendously when this animal is not near them. Death by automobile is a common end for such dogs, but most are simply given up to rescue when they become too huge a burden for the family who bought them as a pup. Many will never be placed due to their poor social skills. Of course there are the sucess stories--but you cannot plan on being one of them necessarily. Without early idenfication, owner-support & quality training the prospects are poor. Which is why sensory deficient dogs so often end up in rescue/re-homed. Even breeders who make them do not necessarily know how to cope with them.

A simple explanation of the various problems associated with lack of pigment is presented here.

B. BREEDING: White danes first & foremost *ALL* have at least one DISQUALIFYING fault (of color) & those considered "useful" for breeding are typically sensory deficient as well . Dogs with disqualifying faults can be registered, but not ethically bred by many people's standards. Some breed clubs & registries and even some countries control the breeding of merle dogs just to avoid the production of these white merles. White (merles) used in a harl breeding program, MM "double merle" whites carrying the harl factor, are statistically less than 15% of dogs born appearing as predominately white. These candidates for harl-production are nearly always deaf & usually have eye defects, often so subtle they are missed unless a CERF exam is done. Deaf stud dogs may be manageable by experienced people, but bitches rarely are. Both may well try to escape to get mated, and, a deaf dog, unsupervised in public is very likely to be hit by an automobile & killed. A deaf dog is often more difficult to rear, so, as a stud dog, he may be a challenge to collect & to breed. Some are sterile & others are too behaviourally abberant to breed properly. There are many in Danes who believe deaf dogs produce more deaf/defective dogs & there is much scientific evidence to back up this opinion. Which means another ethical dilemma for any caring breeder of course. Health checks are more complex with a sensory deficient dog, & the better sort of bitch owner in general doesn't choose a deaf white as the first choice for a good bitch, so the quality of his offspring will likely be poor, as the bitches who frequent him are likely to be of lesser quality than those going to a Champion/finishable Mantle or Harlequin. A deaf brood bitch cannot often raise a litter successfully at all & she will, as a deaf bitch, need help. She cannot hear her pups & deaf bitches will kill some of their pups by crushing them & lose a few more by not knowing they are strayed too far, so they die of cold. Some have NO maternal instincts & will not accept the pups at all; some will even savage & kill them. You would have to be with them practically 24 hrs a day until they were old enough (2 months) to leave to raise a litter from a deaf responsibly. It is so hard to even try this when you are an expert & anyway, pups raised this way (essentially as orphans) may never be truly normal, even if they do make it. Lots of things are said about whites to justify breeding them, but whites are a gamble really & unnecessary to a Harlequin breeding program. It is true you can breed the "right" sort of white to a "black or boston" and get no deaf/blind dogs. It is NOT true you will necessarily get all harls or the harls you get will have better color than those from Harl x Harl or Harl x Mantle breeding. Most white x black breedings produce a mix of harl/merle pups. Some produce all merle, some all harl. But you can safely stick to breeding dogs who are correct to the standard (in color as in all other things) & breed only show-marked/breed quality Harlequins & Mantles. You can even avoid the production of these white merle dogs by breeding only Harlequin to Mantle (rather than Harl to Harl). Breeding whites are a gamble, as they all basically look alike, but genetically they can be of various types. So the gamble is even more extensive than potentially risking your reputation, misidentifying the parents or the pups, having the health of the dog/bitch/pups in question, the reduced likelyhood of raising a normal litter of pups people want to buy (as if that is already not enough!): unless you are really lucky, your "White" is not even going to be that "special" genotype (i.e. genetic harl-factored white merle=HhMM) that *CAN* even be a harl-producer of any merit: There is no reason to produce "double merle" Danes, that is Whites, given you can breed Mantle to Harlequin and use dogs correct under the standard. There is arguably less reason to actually use Whites in a breeding program--esp. deaf whites.

There are at least THREE obvious general genotypic classifications for the "white" dane are well documented (with likely subcategories).

1. Dominant (double merle) white (MM). (The "typical" deaf white with no head pigment, a spot somewhere on the body.)

2. Recessive (piebald) white (mm). (The dog with a cap of black on it's head, a big round/oval spot over the ribs/tail root.)

3. Hybrid white (Mm). (The "light marked" harl, at least some of the time.)

Under the category of Dominant white, two further genotypes (for the same phenotype) likely exist: harl-factored (HhMM) and merle-only (hhMM). Only one of which is even potentially useful to a harl breeding program (& that the one likeliest to be defective). A further sub-category of 3 variants at the S locus may also exist in lines that produce "white harls" & "merlikins" (HhMmss/hhMmtwtw) &/or other piebald whites (mmss). [ss as shorthand for sp/sw]

Under the category of Recessive (piebald=Boxer) white, 3 basic genotypes (for the same phenotype) exist: sp/sp sp/sw & sw/sw. None of these "double recessive whites" are of ANY use to any harl breeding program--they are "affecteds" who spread the genes for undermarked, white bodies dogs (i.e. white-factored harls & mantles) which confuse the issue in harlequin breedings while making all their offspring carriers of mismarkings.

Under the category of Hybrid white, you have dogs which carry all the problems of the above two categories (being a hybrid of them both), so are potentially the most confusing, and therefore damaging of all to the gene pool, as the most difficult to identify and least predictable in their offspring. At least 50% are obviously incapable of producing the harlequin variant, as they lack the harl factoring at M (i.e. the "H" factor).

This gives 21 (TWENTY ONE!) GENOTYPES for the "WHITE DANE" & of those 21, ONLY THREE (3) are potentially useful to the harl gene pool, with only one of those three being true breeding, (the other two being hybrid, thus adding to even MORE mismarks) & that true breeding one almost always defective, difficult to rear & care for, a disqualification under the standard, and with no guarantee of quality offspring or even of being fertile. (Note: For simplicity's sake I have avoided the extra complication of the Tweed factor which produces merlikins & "harli-merle" mixed black-grey-white non-standard harl-like dogs. Adding this in makes for an even more complicated equation, naturally.)

Just to look at all the potential genotypes for the "WHITE" Dane that correspond to that single phenotype (white) & you can understand why it generally makes no sense to risk rearing & breeding these animals. (Add to that the difficulty, esp. with a deaf female, of successfully keeping her to breeding age, then her breeding & rearing a healthy litter?) There are expections, but most quality harlequin breeders rarely if ever use mismarks in their breeding program. The odds of producing correctly marked animals is so poor (& this world is already overflowing with mismarked dogs, please), the "gamble" seems hardly worth it to the breed & the general dog population, let alone the breeder at hand, and better choices, really, must generally be available to the conscientious & knowledgeable breeder.

AND THIS IS COURTESY of Neil O'Sullivan, Ph.D. (who is listed in the references as an author on harlequin color); geneticist, 2d generation breeder of Danes & Chairman of the GDCA Color Research Committee:

"I have had a number of emails this year asking about breeding deafs. My advise<sic> is always the same. Don't do it.While the placement of pigment seems almost random on homozygous merles (Whites...most in fact have some color), harlequins and merlequins, it in fact is not totally random. You will note that the somatic mutations which causes otherwise white areas to turn gray or black occur more frequently on the head around the ears and eyes and over the rump and the top of the tail. I speculate this has a selective advantage and so nature has selected for genes which interact with the MM hh, Mm Hh, and Mm twtw genotypes to prefer pigment in these areas. Thus the MM is more likely to be Mm or mm on the head (especially near the ears and eyes) while the rest of the body is still MM (and therefore white)."

"You will note that the use of deaf whites is highly correlated with more deaf whites in the progeny or grandprogeny. Also the use of deaf whites and deaf merlequins correlates with a higher incidence of deafness and eye defects even in the harles. Also hearing whites, merlequins and others have a higher frequency of hearing in their progeny too. You will note of the White dogs I knew Laura (BMW) to breed all could hear, Vanilla, Johnny and YamYam for sure.

"I am assuming you know the basics of harlequin color genetics here. A harlequin is HhMm in genotype with the gray of the merle genotype converted to white by the Hh genotype. Thus the Harlequin is predominantly a White dog with black torn patches, a merle is (hh Mm) a gray dog with black torn patches and a merlequin is a modified merle ( hh Mm tw tw). A harlequin with tw tw genotype is usually a "mixed" color with almost as much merle as black patches. Tw the non tweed allele is dominant. But I digress."

"In short...I think breeding from deaf dogs is not smart as it increases the frequency of genes which do not encourage pigmentation of the head and thus middle ear and retina and in so doing not only set us up for more deaf whites but deaf merlequins and deaf harlequins too. Yes, deaf harles, as you know from rescue are not as rare as we breeders would like.
You may quote this if you feel it it helpful."

NOTE THAT the term*WHITE DANE* really should be limited to describing the genotype MM: a homozygous "double-merle=white merle" dog, which is not always all white in appearance. But, by phenotype (appearance), rather than genotype (genetic identity), many dogs (Danes) are called "White," (just as many true-White Danes are called "merlikin" or "lite-harl"). So all potential iterations of what could be a white-by-appearance/registry Dane are discussed above. "Whites" who are mm=piebald white should actually be registered as B&W dogs & are a kind of mismarked Mantle; "whites" who are Mm should be registered as mismarked harls (HhMm) or maybe merles (hhMm) (if you could sort them out from the true whites, that is), so that MM whites can be properly identified. But this logic is not currently applied, & dogs are simply identified by appearance & registered at will, often without consideration to genotype. This makes reading pedigrees difficult & it's hard to truly know the genetics of these white parents often. Yet another strike against them for many people who want to have properly marked pedigrees. For more information,details of inheritance & further reading, see the references listed below.

Harl=H is a dominant factor postulated to "take the grey out of the merle" dog, thus producing the Harlequin variant. Double dominant harls (HH) do not exist, as, under this theory, the homozygous state is lethal to *all* the embryos. All living harls are Hh hybrids. They also are Mm merle hybrids. Merles lack the H=harlequin factor & thus cannot contribute to the production of harls (neither can merlikins, except to help produce improperly marked "tweed" harls). Blacks/Mantles from Harlequin breeding could, in theory, carry for the Harlequin factor. Thus some (not all!) Mantles, for example, can contribute to the production of harls when bred.

Tweed=tw is a recessive factor postulated to give a mixed "swirly" look to the grey-to-black areas, with lots of ticking/flecking in the merle patches, & a lack of distinct, crisp black patches on the harl. Tweed factor is recessive to non-Tweed, with non-Tweed giving the crisp look in a harl that is desired. Thus well-marked harls can carry for tweed (Twtw) & one should avoid breeding from tweed (twtw) dogs (such as merlikins), as this is breeding an "affected" (mismark), thus spreading genes for incorrect color & producing carrier offspring.

Another article on the White Dane

ASCA position on Deaf Whites

Dr. Strain's article on deafness & it's recognition

Dr. Cattanach's article on deafness, white coat & blue eyes

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