This article is from the Genetic Diseases in Dogs FAQ, by Gary Mason.
Many diseases in the domestic dog are genetic in origin. Examples are
vWD, Collie Eye Anomaly, portosystemic shunt, hemophilia, Scottie
Cramp, hip dysplasia, Legg/Calv Perthes, medial patellar luxation, and
craniomandibular osteopathy (CMO) -- the list is very long. So far,
over five hundred genetic diseases have been identified in purebred
dogs, and over a hundred in mixed breeds. They can affect
conformation, health (virtually all systems in the body are subject),
and temperament. In Scotties alone there are 36 identified genetic
diseases, with similar numbers affecting each of several other terrier
There is a great deal of scientific research being performed on the
identification of the specific causes of genetic diseases. Because
some of the diseases exhibited by dogs are also evident in humans --
vWD is the most common human inherited blood disease -- some benefit
could derive from canine research which would be of use in pursuing
the human form of the same, or related, diseases.