Genetic diseases are alarmingly prevalent in dogs, and we are not just talking about pure bred dogs either. In fact, all dogs carry around 4 or 5 defective genes on average making genetic diseases the most common cause of illness in dogs. Perhaps the main reason for genetic defects in dogs is that most tame breeds come from a very small genetic pool; some researchers believe that the dogs share a common genetic ancestry that can be traced back to only three female wolves living in China. Moreover, humans bred specific traits in dogs which continued limiting the gene pool throughout the evolution of dogs.
Some 500 genetic diseases have been discovered in dogs and basically all dog breeds are known to be afflicted with various genetic diseases. Take hip dysplasia as an example. This orthopedic disease has been noted in 170 different breeds of dog. And which dog breed is most likely to suffer from a genetic defect? The poodle. In total there are nearly 150 genetic diseases that can affect poodles, likely because of the popularity of this breed. As dogs become more popular they’re ancestors are usually subject to more inbreeding making them increasingly affected by genetic problems.
Recently, solving the problem of genetic disease in dogs has become a half billion dollar annual effort. Because all breeds of tame dogs were essentially created by artificial means, the problem with genetic defects is likely never going to be overcome. Cross breeding dogs and other measures, like mapping the dog genome, can help us understand what we need to do in the future to prevent and reduce the prevalence of genetic disease. Still, as it stands, all dogs are affected by defective genes and reversing genetic diseases in dogs will certainly be an arduous effort.