I think that's a pretty bold statements that genetics cause DA. Even the most "ruthless" pitbull from the fighting pits can be rehabilitated to play with dogs. Dogs are MEANT to be in packs. They are MEANT to interact and play with each other. Socialization correctly will avoid DA. I just don't think humans know how to do it properly.
For instance, small lap dogs that were not bred to be dog aggressive, but many many are. Just like pitbulls that were bred to fight dogs can get along fine and play with others. Genetics are just a small part of the puzzle. I hate blanket statements that "bully breeds can snap at anytime, yadda yadda yadda". Dog's don't just snap. Humans just don't recognize the signs as they develop. They can be very subtle, but because we aren't dogs, we don't know what is going on in their minds that changes the way they mature and interact with other dogs. I am sick and tired about owners on here saying the "bulldogs cannot be trusted, they are ticking time bombs, they can't be friends or learn to be social with other dogs." it's becoming more of an issue on this forum and to me, it's JUST as bad as BSL.
I worked very hard to socialize my dog, educate myself on his strength and how his breed interacts with other dogs, and mold his behaviour despite his genetics. He is the most social dog I have ever met. He will NOT just snap. If he one day becomes DA, it will be MY fault as his owner for not recognizing the signs that something is pissing him off.
Bulldogs are dogs first, and dogs are meant to interact with other dogs. Plain and simple. Humans create the "genetics" and genetics DO NOT rule their psyche. Just like all Asians aren't brilliant, and all black people are fast. Racism, BSL... Coincidence?