Not a huge fan of pit bull terrier dogs, (is it Pitbull or Pit Bull?), mostly becuase of the way that people raise then and what they train them to do. But, at the same time, I really don't have anything against them either. They are agressive, but a lot of that is trained into them. Sort of like a person that trains to get a boxer, but is raised in a bad home, he ends up having the body to do damage and the mindset to not care. See the difference between the photos below, some look like a guard dog, some look like a dog ready to play with kids.

Anyhow, this thread was about something abnormal though, with some type of genetic difference causing extra muscle mass. It's very interesting overall I think.

Pitbull Dog Photos

A great look at the Pit Bull Terrier, also known as the pitbull terrier, or just the Pitbull.

A great photo of a black pitbull dog.

Great looking red nose American pit bull dog.

Great shot of a Pitbull dog standing at attention.