Originally Posted by MrVampire181
As far as I know they contain no giant genes.
I've been reading up. It appears there is no such thing as a simple gene for giantism. There are gene combinations which effect the timing or the expression of certain tendencies or characteristics, like the development of the thyroid and how much growth hormone it produces. This is the way it seems to work with most animals.
That's very oversimplified, but I'm doing as much research as I can without a background in genetics. I'll post a longer article when I feel I have a handle on it.