Train the dog in front of you is a popular motto in dog training. It basically means, don’t worry about other elements and just focus on the dog you are working with.
Now, though, with the increasing popularity of DNA testing could send trainers off on wild tangents if they give too much credit to behaviors based on breed and not just looking at the dog in front of them. Another possible pitfall could be owners relying too much on genetic testing for health concerns instead of getting more reliable information from testing.
On the other hand, it could be fun to find out what Fido has in his history.
Check out this article on NPR for more.