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.

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.