Scientists are developing maps of the canine genome. Once completed, this will guide researchers to an understanding of the underlying genetic causes of diseases in dogs, including a determination of the mutations that actually cause the disease. With this information, diagnostic tests can be developed so that breeders can reduce or eliminate the incidence of genetic disease in their lines. So far, researchers have located the genes that cause narcolepsy (sleeping sickness) in dogs as well as those for three inherited diseases that affect the retina. They have also developed more than thirty tests to identify heritable canine diseases. It's possible that the next ten to twenty years could bring tests for all known single-gene canine genetic diseases, allowing these diseases to be eliminated through genetic testing and selective breeding.

As scientists work to decode the canine genome, their discoveries will allow breeders to use genetic information to prevent disease through more careful breeding. They will also allow veterinarians to provide new forms of treatment for genetic diseases, such as inserting a normal gene into the DNA of cells to compensate for a nonfunctioning or defective gene, a technique known as somatic gene therapy. In the not-too-distant future, if your veterinarian tells you that your dog has a hereditary disease, your options for treatment may go beyond surgery or chemotherapy or lifelong medication. Instead, your veterinarian may simply prescribe nose drops containing a retrovirus that will deliver a normal gene to correct the dog's problem.