Nope
There's a lot more variability than breed. The people pushing this outdated BS like OP are using the same arguments and pseudoscience racists use.
Behavior was another story. Less than one-quarter of the differences in personality from dog to dog could be explained by genetics. Some behaviors, like retrieving objects and human sociability, were more heritable. The researchers speculate that retrieving may have helped dogs’ wolf ancestors hunt, and that humans likely selected for friendly pooches in the early days of dog domestication.
But most behaviors did not have a strong genetic component, including playfulness around other dogs and (yes, it was in the survey) whether a dog circles before it defecates. “That probably has a lot more to do with where you take your dog to poop,” says Elinor Karlsson, director of vertebrate genomics at the Broad Institute, who oversaw the study.
And when it came to dog breeds, personality varied widely within the same pedigree. Labradors could be loving or standoffish. German shepherds, easy to train—or impossibly headstrong. Just 9%, on average, of the personality differences between pups were related to their breed, the team reports today in Science.
Some breeds even defied their stereotypes. Pit bulls, for example, (though not an official AKC breed) were not more aggressive than other dogs, despite their reputation in some quarters as dangerous. The results, Karlsson says, “match what the dog world has told us”—that the behavior of these animals is shaped by their environment, not their breed.