Dog Degenerative Myelopathy Genetic Testing and Prevention

Degenerative myelopathy is caused by a SOD1 gene mutation that can be tested before breeding, providing an opportunity to dramatically reduce disease prevalence through responsible breeding decisions.

Key Facts

DM is associated with a SOD1 gene mutation (c.118G>A) in a homozygous state in most cases
Testing identifies dogs as clear (N/N), carrier (N/DM), or at-risk (DM/DM) for the mutation
At-risk dogs have an approximately 80% lifetime risk of developing clinical DM
Carrier-to-carrier breeding produces 25% at-risk offspring; carrier-to-clear produces 0% at-risk
OFA accepts DM DNA test results and maintains a public registry of tested dogs
German Shepherds, Boxers, Rhodesian Ridgebacks, and Pembroke Welsh Corgis are most affected
DM testing costs approximately $70-150 per dog and prevents years of progressive neurological disease

Welfare Considerations

DM genetic testing represents one of the clearest welfare prevention opportunities in companion animal medicine. At-risk dogs develop progressive paralysis over 6-18 months that has no treatment. The gene mutation can be eliminated from breeding populations within a few generations with consistent testing. The welfare calculus is unambiguous: spending $70-150 on genetic testing before breeding prevents lifetime neurological disease in potentially multiple offspring. Breed clubs that make DM testing mandatory for registered breeding dogs demonstrate the most welfare-effective approach.

What You Can Do

Test all dogs of at-risk breeds before any breeding decision using OFA DM genetic testing
Never breed two carrier dogs together - always pair carriers only with clear tested individuals
Ask breeders to show OFA DM test results before purchasing a puppy of an affected breed
Support breed club campaigns making DM testing mandatory for registered breeding
Advocate for genetic health testing requirements in kennel club breed registration standards