Henry is an odd mix - half German Shepherd and half Tibetan Mastiff. He was sold as a purebred Tibetan Mastiff, by an inexperienced breeder, and to inexperienced owners. He and his sister were a little much for them, and after many travels he ended up in the pound.
We didn't know what we were getting from the shelter, just that he was a big guy and would make a good buddy for our CO. We had just got the DNA results back (GSD and misc Asian Dog) when we ran into his sister and her people at a local humane society event. They recognized him at once, reconnected, and told us his history.
He's a good guard dog, a loyal servant and companion, and generally takes life seriously. He lets the CO push him around, because that's his job. But I think he'd rather work for a person. He loves his people devotedly and is would do anything for his pack. But he's very doubtful about anyone new, especially other dogs, and men at the front door.
He made great progress at puppy school with clicker training. We're convinced his brain, just like his looks, is mostly GSD with just a pinch of TM.