Yes, there are several DNA tests that you can do to check to see if he is purebred or not. Google Dog DNA tests and you'll have your pick of several. As for the aggression, it can be coming from anywhere. The best thing to do is to contact your local positive reinforcement trainer and get him/her to see the aggression first hand. He/She will be able to help you from there.
Answered by Anonymous - 5/1/2014 6:07:20 PM