I was browsing Craigslist today looking at all the pet ads. There was an ad for a chocolate lab and they posted a couple of bad pictures. I could see that there was a bit of feathering on the dog, and thought it looked a little like a Flatcoat. The ad specified that the dog was "full blooded" but without papers. So I contacted the guy to ask. He emailed me back saying that no, he was sure that it was full blooded (his term) and that his vet had said that the dog had the very rare long hair gene. Two of the pups in the litter had long hair, and the rest had short coats.
Now, I know that Labs can be mismarked and come out in some different colors due to recessive genes, but I've never heard of the long haired gene. But since this guy's vet told him about it, I figured there was no use arguing. BTW, he said that he was getting rid of him because his other dog got hit by a car and lost a leg and couldn't keep up with this guy anymore.