Greyhound neuropathy (GN) testing for dogs

Greyhound neuropathy (or polyneuropathy) is a hereditary health condition that affects only dogs of the greyhound breed, and cross-breed or part breed dogs with some greyhound ancestry.

The condition leads to a range of debilitating symptoms in affected dogs, including a peculiar high stepping or hopping gait, intolerance for exercise, and muscle weakness in all four limbs. Later progression of the condition leads to muscle atrophy, loss of control of bodily movements, and alterations to the vocal cords, muzzle and throat that can lead to an inability to vocalise, or strange vocal sounds being produced in place of normal barking.

The condition usually presents when the affected dog is still a puppy, and generally, most affected dogs are euthanized by the time they reach a year old, as the condition cannot be cured and has an extremely negative impact on the dog’s quality of life.

The Kennel Club, in association with the British Veterinary Association, views greyhound neuropathy as a significant enough potential threat to the health and wellness of the breed as a whole that they strongly advise that breeding stock be tested for the markers of the condition before being permitted to breed.

In this article, we will look at greyhound neuropathy in more detail, including how the condition affects dogs, how it is passed from dog to dog, and how dogs can be tested for the condition. Read on to learn more.

More about greyhound neuropathy

Greyhound neuropathy is a hereditary health condition that cannot be passed on or transmitted from dog to dog other than through their breed line, as the condition is passed on from parent dogs to their offspring. Generally, the condition’s early symptoms become apparent when the affected dog is very young, sometimes just twelve weeks of age. The condition progressively worsens by means of muscle wastage, breathing difficulties and a range of other symptoms that alone will often ultimately prove fatal; generally, it is in the best interests of affected dogs to have them put to sleep before the condition becomes acute.

Greyhound neuropathy is caused by a gene mutation in the NDRG1 gene, and based on sample study data, the mutation itself may be present in around a quarter of all dogs of the breed. Most sampling for the condition has been performed in show dogs, however, and in an equivalent sample taken from racing greyhound lines, the mutation was found to be much less prevalent in sample populations.

What sort of dogs can it affect?

As the name implies, greyhound neuropathy is a condition that exclusively affects the greyhound dog breed, although it can of course be passed on to dogs of mixed breeding that contains some greyhound ancestry.

The condition usually begins to present with symptoms in dogs under a year old, and affected dogs rarely live beyond the age of one, either because they die as a result of the condition or are humanely euthanized in the best interests of the dog.

It is important to bear in mind the fact that dogs can be carriers for the condition and so, run the risk of passing it on to their offspring without necessarily being affected by the condition themselves.

How does the heredity of greyhound neuropathy work?

Greyhound neuropathy is an autosomal recessive condition, which means that inheriting just one copy of the mutated gene (from one parent) is not enough to cause the condition in the offspring on its own; different combinations of heredity lead to different combinations or results in any given litter.

• If neither parent dog is affected by or a carrier for the condition, they will not pass anything onto their offspring.
• If one parent is a carrier and the other clear, half of their litter will be carriers and half clear.
• If one parent is clear and one affected, all of their litter will become carriers.
• If two carriers are mated, half of their litter will be carriers, a quarter clear, and a quarter affected.
• If a carrier and an affected dog are mated, half will be carriers and half affected.
• If two affected dogs are mated, all of their litter will be affected too.

How to get your dog tested

Testing potential parent dogs for the markers of greyhound neuropathy prior to breeding is important, so that breeders can make an informed decision on the right match, and the health of their subsequent litter.

In order to test for the condition, you will need to ask your vet to take a blood sample or buccal swab (a sample of the cells on the inside of the dog’s cheek) and this will then be sent off to one of the approved laboratories that can perform the test, and the results then returned to you.

To find a laboratory that can perform the test, check out this list on The Kennel Club’s website.