Paroxysmal Dyskinesia

Paroxysmal dyskinesia (PxD) is a neurological disorder causing episodes of abnormal tone or movement of limbs. Affected dogs seem normal between these episodes.

Key Signs

Episodes of abnormal tone, Abnormal movement of limbs.

Age of Onset

0 to 2 yrs

Juvenile onset

Inheritance

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

Moderate-high likelihood

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

What to Do

Here’s how to care for a dog with PxD

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 PxD

Clinical signs emerge between 8 months and 3 years of age with the median of 2.25 years. The disorder causes episodes of flexion and extension of the hind limbs. Mild episodes can be seen as exaggerated flexion of one hind limb while walking or as a stiff gait. Severe episodes can include the front legs and the dog may be unable to walk or stand. Affected dogs are conscious during these episodes. An episode could last as little as several minutes up to over four hours. Frequency can vary as well: from once every few days to over 10 times a day. Affected dogs seem normal between these episodes. The severity of these episodes tends to increase over time.

Antiepileptic medication (especially benzodiazepines) can be used but the response is usually not very good. For severely affected dogs euthanasia is often elected on welfare grounds.

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 develop. A carrier dog with one copy of the PxD mutation can be safely bred with a clear dog with no copies of the PxD mutation. About half of the puppies will have one copy (carriers) and half will have no copies of the PxD mutation. 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 PxD mutation could develop due to a different genetic or clinical cause.

Technical Details

Gene	PIGN
Variant	C>T
Chromosome	1
Coordinate	14,705,240

All coordinates reference CanFam3.1

References & Credit

Credit to our scientific colleagues:

Kolicheski, A. L., Johnson, G. S., Mhlanga-Mutangadura, T., Taylor, J. F., Schnabel, R. D., Kinoshita, T., … O’Brien, D. P. (2017). A homozygous PIGN missense mutation in Soft-Coated Wheaten Terriers with a canine paroxysmal dyskinesia. Neurogenetics, 18(1), 39–47. View the article