We adopted a badly abused one year old dog after the vet did surgery to save the dog's life. She is now almost 7. She is pit,lab and boxer mix. You would think after a man kicked her so hard he shattered her kidney that she would not be kind to everyone but she is very sensitive and nice. We used to have a Min Pin that would bite everyone that came to our house and I hated that dog. He is no longer alive......so I don't believe it is just a certain breed that is dangerous.