I don’t buy that. The Pitbulls of Australia seem to have a habit of mauling and killing small children on a regular basis, more so than any other dog breed.

Maybe the Pitbulls in Australia are different but I doubt it.

Pitbulls are often trained to be mean. They are supremely athletic and strong, so they are the logical choice for fighting dogs, guard dogs, etc.

I can't say whether or not there is a genetic component to incidents of mauling involving pitbulls, but people are a large part of the problem too.