Yes, IVDD (intervertebral disc disease) is strongly hereditary in dogs. The primary genetic driver is a specific mutation called the FGF4 retrogene on chromosome 12, which causes premature hardening and calcification of spinal discs starting as early as birth. This mutation acts in a dominant fashion, meaning a dog only needs one copy to be at increased risk. While genetics is the biggest factor, environmental influences like body weight and exercise also play a role in whether a predisposed dog develops symptoms.
The Gene Behind IVDD
Two related mutations explain the short-legged body type seen in breeds like Dachshunds, Corgis, and Basset Hounds. Both are copies of a growth factor gene (FGF4) that inserted itself into new locations in the dog genome. One copy sits on chromosome 18 and is responsible for short legs, a trait called chondrodysplasia. The other sits on chromosome 12 and causes both short legs and abnormal spinal discs, a condition called chondrodystrophy.
It’s the chromosome 12 copy that drives IVDD risk. Dogs carrying this mutation experience early degeneration of the soft, gel-like center of their spinal discs. In a healthy disc, that center stays hydrated and flexible, acting as a shock absorber. In affected dogs, it dries out and calcifies during the first year of life, sometimes beginning before birth. This brittle, hardened disc material is far more likely to rupture and press into the spinal cord.
Because the two mutations have different effects, it’s theoretically possible to breed for short legs (using the chromosome 18 gene) while reducing IVDD risk (by selecting against the chromosome 12 gene). Breeds like Basset Hounds and Dachshunds carry both mutations, while Beagles and American Cocker Spaniels typically carry only the chromosome 12 version.
Which Breeds Are Most Affected
Dachshunds have the highest IVDD prevalence of any breed. An estimated 19 to 24 percent of Dachshunds show clinical signs of IVDD during their lifetime, with studies consistently finding surgical-level disease in about 15 percent of the breed. French Bulldogs are the second most commonly affected breed, with roughly 8.4 percent developing clinically significant disc disease.
Other breeds classified as chondrodystrophic, and therefore at elevated genetic risk, include Beagles, Basset Hounds, Cocker Spaniels, Pekingese, Shih Tzus, and Pembroke Welsh Corgis. In many of these breeds, the chromosome 12 mutation is “fixed,” meaning every dog in the breed carries two copies. When a mutation is fixed in a population, genetic testing within that breed isn’t especially useful because every individual will test positive.
Mixed-breed dogs are not exempt. The chromosome 12 mutation has been documented in mixed breeds, particularly those with any short-legged ancestry. If a mixed-breed dog inherited the gene from even one parent, they carry increased risk.
How Hereditary IVDD Differs From Age-Related Disc Disease
Veterinary medicine distinguishes two main types of disc disease, and they have different genetic profiles. Hansen Type I is the hereditary form linked to chondrodystrophic breeds. The disc center calcifies early, becomes brittle, and eventually ruptures acutely through the outer disc wall into the spinal canal. This tends to happen suddenly and can cause dramatic symptoms like sudden paralysis or severe pain. Dogs with Type I disease typically show symptoms between 3 and 7 years of age.
Hansen Type II is a slower, chronic form of disc disease more common in larger, non-chondrodystrophic breeds like German Shepherds and Labrador Retrievers. Rather than an acute rupture, the outer wall of the disc gradually bulges into the spinal canal over time. This type is more closely tied to aging and wear than to a single inherited mutation, though genetics still plays a contributing role. Symptoms tend to appear later in life and progress more gradually.
Genetic Testing Is Available
The Veterinary Genetics Laboratory at UC Davis offers a combined genetic test for both the chromosome 12 (CDDY) and chromosome 18 (CDPA) mutations. The test costs $55 per dog, with a $5 discount when testing three or more animals. Results take at least 15 business days. Unlike some genetic tests that rely on linked markers and estimate probability, this test directly identifies the causal mutations, so the results are definitive rather than inferred.
Testing is most useful for breeds where the mutation hasn’t become universal. In breeds like Dachshunds, where nearly every dog carries the mutation, the test confirms what’s already assumed. For mixed-breed dogs or breeds where both carriers and non-carriers exist, the test can meaningfully inform both health monitoring and breeding decisions. A dog with one or two copies of the CDDY allele has increased IVDD risk, so sharing test results with your veterinarian can help guide preventive care.
Breeding to Reduce IVDD
Reducing IVDD through breeding is more complicated than simply testing for the gene and removing carriers. In Dachshunds, for example, virtually every dog carries the chromosome 12 mutation. Excluding all carriers from breeding would eliminate nearly the entire breed from the gene pool. For this reason, the Danish Dachshund Club has used a different approach since 2003: radiographic screening of the spine between 24 and 48 months of age, accepting only dogs with fewer than five calcified discs for breeding. This calcification scoring approach selects against the most severely affected individuals without collapsing the breeding population.
For breeds where the mutation is still segregating (meaning some dogs carry it and some don’t), direct genetic testing is a practical breeding tool. Pairing a carrier with a non-carrier, or selecting non-carriers when possible, can reduce the frequency of the mutation over generations.
Environmental Factors Still Matter
Carrying the mutation doesn’t guarantee a dog will develop clinical IVDD. Research has identified several non-genetic risk factors that influence whether disc disease becomes symptomatic, including body weight, physical conformation, neuter status, and exercise habits. The findings across studies aren’t entirely consistent, which suggests no single environmental factor dominates, but the overall picture is clear: genetics loads the gun, and lifestyle factors influence the trigger.
For dogs that carry the CDDY mutation, keeping body weight in a healthy range reduces mechanical stress on already-compromised discs. Avoiding high-impact activities like jumping on and off furniture or running down stairs may also help, though no study has definitively proven that activity restriction prevents disc rupture. What is well established is that the disc degeneration itself begins in puppyhood, long before any symptoms appear, which is why genetic awareness matters even for young, healthy-looking dogs.