Why are certain breeds of dogs more prone to certain diseases then others?

I'm curious as to why some dog breeds are more likely to develop or be born with certain illnesses and diseases then other breeds. Like, some breeds are more likely to have epilepsy, others-allergies, and others-cancer.Does anyone know why that is?

just cause of the way they r built

That is why reputable breeders get their dogs tested before breeding.http://www.godivalabs.com/cost.htmlIt is called a predisposed to specific ailments. Like Collies for double eye lashes, bone problems in Danes, skin problems with low immune systems.This also applies to all animals, even us. If your grand mother had cancer you are predisposed to get cancer some time in your life. If a deformed person mates with a healthy person, there is a very strong predisposition for a child to be deformed too.The pit for example has developed many very strong predisposition to all kinds of ailments because BYBers do not test their dogs & just breed in BAD genetic & they don't have a clue as to what they are doing. They just want your money. Same with any BYBer of any breed. Most are very ignorant & don't know what a fault is & will breed just for the money.

It just comes with the territory. Cocker Spaniels are very likely to get hip dyspepsia and ear infections than other dogs. Dachshunds are prone to back problems and a lot of Dalmatians are born deaf. If you go to the American Kennel Club website, they will tell you the medical problems to expect in certain breeds. It's www.akc.org

because of the way the dog is built. I have German Shepherds and my oldest one is having hip problems, it is typical of the breed because their back legs are built differently than other dogs

By the statement "by the way they're built" I'll elaborate on the way they're genetically created.Some diseases are more common in certain populations. For instance Tay-Sachs disease is seen more frequently in Ashkenazi Jews than the general population, assuming that they tend to marry within their group, that disease has more opportunities to pop up in the population. If you look up Dalmatians, the genes that allow for the white coat under the spots also are responsible for deafness in the breed. If you consider that purebred dogs are bred with dogs of the same breed, diseases are more likely because there are consequences for wanting to maintain certain traits in the dog or build them a certain way. If all dogs were allowed to breed indiscriminately, than the ones with less desirable traits would probably die off and dogs would probably move towards fewer breeds, but definitely healthier dogs.