They are high risk dogs as well. Caution should be used equally with regards to children.
Actually, as a dog enthusiast who used to read up on dogs behavior and training for fun, I can tell you that any dog that is not properly socialized can have issues. There are other factors as well. Some breeds require experienced fog owners simply because of their energy level, level of stubbornness, etc.
Most aggression is actually rooted in fear. A fearful dog may very well bite. It's pretty much the only way he can protect himself, after all.
This is why thorough socialization is important. Ideally puppies should be socialized with as many people as possible. Most people don't realize this. It's surprising how ignorant some dog owners are on dog behavior, and this can lead to some unfortunate events.
For example, many people will correct their dog for growling. This is a terrible thing to do. Growling is a warning, see. When a dog growls he is saying "please stop that, it makes me uncomfortable." If you correct this warning mechanism out of the dog, he's likely to go straight to biting. Without warning.
A dog's behavior is a combination of genetics and how it was raised. Some breeds are more prone to aggression than others, but any dog is capable of it.
I had a German shepherd up til about two years ago when she had to be our down due to old age and the issues that came with it. They tend to be one person dogs, and bond very closely to that person. Mine followed me around like a shadow. Great guard dog, too.
I do think she probably hadn't been socialized well as a puppy. I worked with her on that and we made some headway. I was a teenager at the time, so in trying to socialize and 8 year old dog who barely left the house most of her life, I'd advise more caution than I employed. Luckily German shepherds are eager-to-please--or at least mine was. I think that's why I was able to make as much progress with her as I did. I was a teenage girl at the time who thought I was some kind of layman expert on dog training. I know now that I'm no expert. I just like to be informed on the animals I own so as not to cause more problems than necessary.
My current dog is a sheltie/papillon mix. Little guy.
I want another German shepherd one day, though.
My dream dog is a smooth (shorthaired) blue Merle collie. I'm told that they actually have a similar temperament to shepherds. If that's true, that's awesome.
