The coat abnormality commonly known as “alopecia X” leads to significant loss of hair that typically will not be recovered over a particular dog’s lifetime.

It starts as unexplained, symmetrical hair loss on the rear of the dog, moves to the neck area, then to various parts of the trunk, according to Alane Levinsohn, health committee chair of the American Pomeranian Club and a 12-year Pom breeder in Southern California, Calif. The coat on the trunk is affected differently in different dogs, but virtually all dogs retain their head and leg hair, she says. Alopecia X mainly affects Pomeranians, Chow Chows, Keeshonden and Samoyeds, but is seen in a few other plush-coated breeds, such as Alaskan Malamutes and Siberian Huskies.

The disease is also referred to as “severe hair loss syndrome” or SHLS, “coat funk,” “follicular dysplasia” and “black skin disease” or BSD, as the skin of dogs without coat often turns a much darker color.

Alopecia X strikes about 16 percent of Pomeranians, according to a recent survey the APC did with the Orthopedic Foundation for Animals, Levinsohn says. “It did not surprise me because of the frequency I was seeing it. It actually confirmed my suspicions.” Almost all of those dogs lost their coats before turning 5, although it initially happens to some dogs at about age 2.

William H. Miller, V.M.D., a professor of medicine at the Cornell University College of Veterinary Medicine in Ithaca, N.Y., says that he and other veterinary dermatologists originally thought the disease was associated with the adrenal glands. “Everybody was really happy with that for quite a while,” he says until they started doing adrenal sex-hormone panels that revealed no abnormality.

While hair loss, which includes the breaking off of the guard hairs of the outer coat, doesn’t usually start until age 2, Miller says that dogs with the disease have an abnormal coat – “a little woollier, but it still looks OK” – at a very young age. “A lot of these dogs go unrecognized as having a coat abnormality.” Veterinarians and dermatologists don’t start seeing the dogs until they start to lose hair, either at about age 2 or 4 or 5. “There’s a very slow progression in coat abnormality,” he says. “Lots of studies have been done. There’s probably no [single] uniform abnormality in each and every dog,” as to how long the hair loss will continue, how much trunk hair the dog will retain or whether the hair will grow back on its own.

The trouble is hormone receptors in the hair follicles, Miller says. “These dogs have weird receptors, plus or minus weird hormone production issues.”

Research Leads to Answers – Eventually

For a number of years now, researchers have been looking at possible causes.

Tosso Leeb, Ph.D., of the University of Bern in Bern, Switzerland, has led several of those studies in the last five years. One looked at affected and unaffected male Pomeranians, who are almost four times as likely as females to have clinical symptoms of the disease by age 2. The study revealed “a highly significant association of one locus in the genome,” he says. “These results clearly point to the existence of one major genetic risk factor. I am convinced that alopecia X is largely a genetic condition.”

Levinsohn is sure that alopecia X predates Pomeranians “because it also shows up in other double-coated northern breeds.” However, she says, “as we started breeding our Pomeranians for show, something that we inadvertently bred for had that gene close by, so it came as a package.”

Shortly after she got into the breed, Levinsohn says she naively thought she could research pedigrees to keep it out of her lines. “Unfortunately, it’s so pervasive that you can look at pedigrees and say, ‘There’s a dog that’s affected. There’s a dog that’s suspicious.’ But you can also look at pedigrees and scratch your head. Which is why I believe it’s a recessive gene.”

That would mean dogs and bitches carrying the gene are being used for breeding and passing it on – without the breeder having any way of knowing it.

She says that any Pom breeder who breeds for any length of time will at some point have a dog with alopecia X.

While Leeb searches for the genetic component – he’s currently working on a complete genome of an affected Pomeranian to get a “comprehensive list of all DNA variants that might be responsible” – Linda Frank, D.V.M., a professor at the University of Tennessee College of Veterinary Medicine in Knoxville, researches treatments.

She discovered that melatonin, a hormone secreted by the brain’s pineal gland and which helps regulate other hormones, can cause many dogs to regrow their hair, but not permanently. Miller says melatonin does impact the hair follicle receptacles. “It is reported to help a lot of dogs,” he says. “In some dogs, it doesn’t do squat.”

Manon Paradis, D.V.M., M.V.Sc., a professor of veterinary medicate at the University of Montreal in St-Hyacinthe, Québec, Canada, says that “it has apparently been successful in approximately 33 percent of cases. Therefore, in spite of this modest success rate, melatonin is a valuable therapeutic alternative to try because of its safety and low cost. The hair growth observed in alopecic dogs treated with melatonin might be due to either modulation of sex hormone levels, interference with cortisol production, action at the hair follicle level by blocking estrogen receptors (estrogen can inhibit anagen initiation) or actual melatonin deficiency. However all of these proposed mechanisms are based on generalization of work done in other species.”

Other treatments are available, such as a variety of drugs that affect the adrenal glands. “All of the medications are expensive and have a series of side effects associated with them,” Miller says. In addition, males can be neutered. “Very often it will have a positive effect for a short period of time. Usually any effect is lost down the line though,” he says.

Doing Nothing Is Just Fine

Miller, Paradis and Levinsohn say that if all you do is protect affected dogs from sunburn and frostbite, they can live perfectly happy, healthy lives.

“Moreover, it is important to state that benign neglect is considered a valid management alternative,” Paradis says. “Rather than promoting aggressive treatments, one’s efforts should be toward client education and promotion of acceptance of the alopecia (i.e., buy your dog a sweater).”

Levinsohn says that “it’s a visually disturbing thing, but it doesn’t bother the dog.”

She has an affected Pomeranian that wears a sweater in the winter and a T-shirt in the summer. Whether or not you treat the dog, it may recoat spontaneously, she says. But it will lose the coat again. Shampooing also seems to affect re-growth, Levinsohn says. While some people use tea tree oil, she shies away from it because at certain concentrations it can be an irritant. “In my opinion, it doesn’t matter what shampoo you use,” she says. She theorizes that it’s the disturbance of the hair follicles as you shampoo that leads to hair growth. As to her dog that’s coatless, she only washes him when he gets dirty. The hairless skin stays clean and doesn’t get greasy, she says. “He gets put in rotation for bathing just like everybody else.”

If an affected dog has itchy skin, rashes or lesions, “something else is going on,” Miller says. Dogs with alopecia X should have healthy skin despite their lack of coat, although some are susceptible to secondary infections.

The Trouble with Treatment

Any treatment of breeding stock that regrows the coat can create another problem, however. The “rumor” in the Pom world, according to Levinsohn, is that some people will treat an affected dog then use it fro breeding. This, of course, leads to more dogs with the condition and, even if they don’t lose coat, they are possibly spreading the disease to their progeny, whether male or female.

Miller won’t treat any dog with alopecia X hair loss until it’s sterilized. He strongly cautions dog owners and breeders that just because a dog loses coat, it doesn’t mean it has the condition. Cushing’s disease and serious thyroid conditions can also lead to hair loss. It’s important, he says, to rule those out before diagnosing alopecia X, as those diseases can be treated. If untreated, they ultimately lead to much worse outcomes than bare skin, including death.

As for her own kennel, Levinsohn removes any affected dog from her breeding program. She now holds off on breeding any male dog until age 5. If the dog is going to lose its coat, proving that it has alopecia X, most likely it will do so by then. “If we can hold off using them at stud until 5 years of age, we can eliminate using affected dogs for breeding,” she says.

However, Leeb isn’t yet willing to prescribe that protocol to breeders.

“Although alopecia X is a genetic condition, it is very difficult to give clear breeding recommendations,” Leeb says. “We think that a female dog can have the bad genotype, but won’t get affected by alopecia X. Thus, it is extremely difficult to identify female carriers of the deleterious gene variant.”

The future holds better options for breeders, and therefore pet owners, of plush-coated breeds.

“I am fairly optimistic that we will eventually identify the elusive genetic risk factor,” Leeb says. “If this genetic risk factor is identified, it will be relatively simple to develop a genetic test, which will then allow breeders to eliminate or at least to dramatically reduce the frequency of alopecia-X-affected dogs. Unfortunately, I am not so optimistic that this will happen in the next few months. It might take a few more years of hard research to finally get there.”

Then, “If people pay attention to that testing, it will eliminate this disease,” Miller says.