Washington (AFP) – They’re well-known stereotypes: rottweilers and pit bulls are aggressive, while Labradors and golden retrievers are extra friendly. But a genetic study published in the journal Science on Thursday involving more than 2,000 dogs paired with 200,000 survey answers from owners demonstrates that the widespread assumptions are largely unfounded. To be sure, many behavioral traits can be inherited — but the modern concept of breed offers only partial predictive value for most types of behavior — and almost none whatsoever for how affectionate a dog will be, or conversely, how qu…