WHITES: IS IT WORTH THE RISKS?*

OWNING & BREEDING

A. OWNING: White Danes are dogs who generally are "at least" deaf & may well suffer from a variety of other congenital and 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 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 also results in deafness quite commonly as it does the Dalmation, and a series of articles is listed at this site that discuss the generally unsuccessful attempts to raise and 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. Dogs being sold as "merlikins" "lightly marked harlequins" "white & blue," "white with markings," "white with blue eyes," etc. are all 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-all. For more info on neural crest development see:  http://www.teaching-biomed.man.ac.uk/student_projects/1999/moran/  or http://www.google.com/search?q=neural+crest+development&btnG=Google+Search).

The unemotional fact is that rescue fills up with deaf Danes as most cannot be kept as pets. It is also a GDCA Code of Ethics violation to knowingly sell a defective (unhealthy) pup as a pet, and 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 (and surprise) the owner thru the first year or longer. Many animal welfare organizations endorse humane euthanasia for ALL (bilateral) deaf puppies for the puppy's sake, and most white Danes are not only deaf, but may have eye and skin problems as well. Something to think about before condemning breeders who euthanize pups with sensory defects or applauding those who do not. This is not, forgive the pun, a black and white issue. See the list below for the defects associated with White (double merle) Danes and note many of these are very serious problems, not all of which are obvious to the casual observer at 2-3 months. Note also that apparently about 50% of white merle dogs are so defective they do not survive to birth. So the ones we see are the ones with "just minor" defects--minor enough that is to have not ended in fetal death. But a gene that kills 50% of those carrying it (in a double dose) cannot be dismissed or ignored. Recall also that "just" deafness & "just" poor sight are not so minor to a dog, and the lack of proper sensory equipment is for them a hardship indeed. Such dogs not only normally need a "helping" dog to get along day to day, the bite incidence and car accident incidence in sensory-deprived dogs is *VERY* high--as high as 80% by some studies. Certainly there are success cases in keeping an otherwise "healthy" deaf dog, but these success cases are far outnumbered by the failures. Not a nice life it would seem, is in store for the average deaf and/or blind Dane. Hence 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 when they do they give them away--they do not sell them.

1.       Congenital CATARACTS associated with micropthalmia. Blinding disorder.

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

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

4.     Convergent strabismus.  Cross-eyed – affects vision.

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

6.     Micropthalmia – tiny eyeballs – often lead to total blindness and most have very poor sight from the start.  Often the eyeball must be removed.

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

8.     Heterochrommia iridis/hypochromia iridis – lack of iris pigment – causes blue eyes and is associated with deafness and can be associated with other eye defects in predominately white dogs.

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

10.  Merle deafness – develops in the first month of life and is permanent and often debilitating to proper social development of the dog.  Usually bilateral; testable by no later than 6 weeks; associated often with other less apparent defects.  Euthanasia is recommended.

11.   Piebald deafness – is present normally by 4-8 weeks and bilateral deafness can only be objectively confirmed by a BAER test.  When bilateral, euthanasia is recommended.

12.  Demodicosis.  Immune-mediated hair follicle mange.  Increased incidence is reported in harl Danes and especially white and merle pups.

13.  Atopic dermatitis.  Inherited allergies.  Increased incidence is reported in harl Danes and especially white and merle pups.

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

15.  Follicular dysplasia.  A hair coat problem of broken and dull hairs and “pimply” infection with a high incidence in white coated (and 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 and reduced fertility.  Increased incidence 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 and first may only be seen (if seen when young at all) as a (i.e., “runt”) failure to thrive and keep up with the size, weight and activity level of the other pups, but later results in multiple health problems for the dog.  Bear in mind that about 50% of the MM=double merle whites do not survive to birth.

19.  Social instability and inadequacy.  Dogs with sensory defects commonly are unable to interact with their own species as well as with humans with full and satisfactory success.  Such pups may well be identified, isolated and treated as different right from the start by the dam and other littermates.  Many develop poorly, fail to adapt and have multiple problems coping with normal daily activities; they are often described as “shy” or “spooky” and the bite incidence for such animals is high.  Some are picked on, most have trouble with normal events, especially 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 and 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 success stories – but you cannot plan on being one of them necessarily.

B. BREEDING: White Danes first and foremost *ALL* have a DISQUALIFYING fault of color. Dogs with disqualifying faults can be registered, but not ethically bred by many people's standards. Some breed clubs and 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 and killed. A deaf dog is often more difficult to rear, so, as a stud dog, he may be a challenge to collect and to breed. Some are sterile and others are too behaviourally aberrant to breed properly. Health checks are more complex with an obviously defective dog, and 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 and she will, as a deaf bitch, need help. She cannot hear her pups and deaf bitches will kill some of their pups by crushing them and lose a few more by not knowing they are strayed too far, so they die of cold. Many have NO maternal instincts and will not accept the pups at all; some savage and kill them. You would have to be with them practically 24 hrs a day until they were old enough (2 months) to go, to be sure they even survived and there is no guarantee she will even feed them. It is so hard to even try this when you are an expert and 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 and 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) and breed only show-marked/breed quality Harlequins and 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 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 its 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 (and that the one likeliest to be defective). A further sub-category of three variants at the S locus may also exist in lines that produce "white harls" & "merlikins" (HhMmss/hhMmtwtw) and/or other piebald whites (mmss). [ss as shorthand for sp/sw]

Under the category of Recessive (piebald=Boxer) white, three 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 and 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" and 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) and that true breeding one almost always defective, difficult to rear and 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 and "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) and you can understand why it generally makes no sense to risk rearing and breeding these animals. (Add to that the difficulty, especially with a deaf female, of successfully keeping her to breeding age, then her breeding and rearing a healthy litter?) There are exceptions, but most quality harlequin breeders rarely if ever use mismarks in their breeding program. The odds of producing correctly marked animals is so poor (and this world is already overflowing with mismarked dogs, please), the "gamble" seems hardly worth it to the breed and the general dog population, let alone the breeder at hand, and better choices, really, must generally be available to the conscientious and 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, second 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."

*WHITES* 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 are called "White," so all potential iterations of what could be a white-by-appearance/registry Dane are discussed. "Whites" who are mm=piebald white should actually be registered as B&W dogs and 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, and dogs are simply identified by appearance and registered at will, often without consideration to genotype. This makes reading pedigrees difficult and 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 and 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 and 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 & its recognition

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


REFERENCES:
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Copyright 1999 (revised 2001) J P Yousha, CHROMADANE.  All rights reserved.  Our thanks to the willingness to share this article for educational purposes.