Dogs and inherited diseases

Q: I’m thinking of adopting a mixed-breed dog, as my last two purebreds died of inherited diseases. Am I correct in thinking mixed-breed dogs are healthier?

A: Often, but not always. A recent study tested over 83,000 mixed-breed dogs and 18,000 purebred dogs comprising 330 breeds for the presence of genes responsible for 152 inherited diseases.

The study concluded that both groups carry the same gene mutations. Moreover, the 12 most common inherited diseases are the same for both groups.

For diseases caused by recessive genes, purebred dogs are more likely to be affected, but mixed-breed dogs are more likely to be carriers, capable of passing the diseases to their offspring.

Two percent of mixed-breed dogs have genetic mutations that put them at risk for one or more inherited diseases, and 40 percent are carriers of the disease-producing genes. Five percent of purebred dogs have genetic mutations that increase their risk of inherited disease, while 28 percent are carriers.

To view the prevalence of genetic mutations that give rise to specific inherited diseases in mixed-breed dogs and individual dog breeds, visit the researchers’ website at mybreeddata.com.

If you do adopt a mixed-breed dog, talk with your veterinarian about genetic testing to determine what breeds make up your dog and whether your dog is at risk for any inherited diseases.

Lee Pickett, V.M.D. practices companion animal medicine. Contact her at askdrlee@insurefigo.com.