After they started calling it Fannie Mae, this turned into a cute little game with Freddie Mac, Farmer Mac, Sallie Mae, Ginnie Mae, and I don’t remember what else.
Fannie Mae finally gave in a few years ago and trademarked “Fannie Mae” and started doing business under that name, though their legal name remains Federal National Mortgage Association. (My wife works for FNMA, or, as I like to say, The Big Fannie.)