Question

what are 3 breeds of dogs that have been negatively affected by selective breeding and what was the effect?

Answer 1

In the same way inbreeding among human populations can increase the frequency of normally rare genes that cause diseases, the selective breeding created the hundreds of modern dog breeds.

Explanation: Most dog breeds when breeding a different breed of dog they are can conclude ether good or bad. Most of the time it's a bad result because the dog is violent or has a disease.