Epidermolytic Hyperkeratosis

Epidermolytic Hyperkeratosis is a skin disorder that causes the skin to be fragile and easily damaged from birth followed by thickening of the skin in adulthood.

Key Signs

Fragile skin, Hyperkeratosis, Hyperpigmentation

Age of Onset

At birth

Present at birth


Autosomal Recessive

For autosomal recessive disorders, dogs with two copies of the variant are at risk of developing the condition. Dogs with one copy of the variant are considered carriers and are usually not at risk of developing the disorder. However, carriers of some complex variants grouped in this category may be associated with a low risk of developing the disorder. Individuals with one or two copies may pass the disorder-associated variant to their puppies if bred.

Likelihood of the Condition

High likelihood

At risk dogs are highly likely to show signs of this disease in their lifetime.

What to Do

Here’s how to care for a dog with Epidermolytic Hyperkeratosis

Partner with your veterinarian to make a plan regarding your dog’s well-being, including any insights provided through genetic testing. If your pet is at risk or is showing signs of this disorder, then the first step is to speak with your veterinarian.

For Veterinarians

Here’s what a vet needs to know about Epidermolytic Hyperkeratosis

Affected dogs suffer from fragile skin, hyperkeratosis (thickening of the skin), and hyperpigmentation (darkening of the skin). Mechanical trauma can cause sloughing, erosion, and ulceration of the fragile skin. Sloughing of the skin can be observed in puppies only a few days old. Hyperpigmentation and hyperkeratosis are present in adulthood. Footpads, hair, teeth, and claws are unaffected.

Treatment is supportive care and symptomatic depending on the severity of the dog's clinical signs.

For Breeders

Planning to breed a dog with this genetic variant?

There are many responsibilities to consider when breeding dogs. Regardless of test results it is important that your dog is in good general health and that you are in a position to care for the puppies if new responsible owners are not found. For first time or novice breeders, advice can be found at most kennel club websites.

This disease is autosomal recessive meaning that two copies of the mutation are needed for disease signs to be shown. A carrier dog with one copy of the Epidermolytic Hyperkeratosis mutation can be safely bred with a clear dog with no copies of the Epidermolytic Hyperkeratosis mutation. About half of the puppies will have one copy (carriers) and half will have no copies of the Epidermolytic Hyperkeratosis mutation. A dog with two copies of the Epidermolytic Hyperkeratosis mutation can be safely bred with a clear dog. The resulting puppies will all be carriers. Puppies in a litter which is expected to contain carriers should be tested prior to breeding. Carrier to carrier matings are not advised as the resulting litter may contain affected puppies. Please note: It is possible that disease signs similar to the ones caused by the Epidermolytic Hyperkeratosis mutation could develop due to a different genetic or clinical cause.

Technical Details

Gene KRT10
Variant G>T
Chromosome 9
Coordinate 21,866,234

All coordinates reference CanFam3.1

References & Credit

Credit to our scientific colleagues:

Credille, K. M., Barnhart, K. F., Minor, J. S., & Dunstan, R. W. (2005). Mild recessive epidermolytic hyperkeratosis associated with a novel keratin 10 donor splice-site mutation in a family of Norfolk terrier dogs. British Journal of Dermatology, 153(1), 51–58. View the article