In the once great nation, as I understand it, gender assignment is "what you feel you are" and not in fact what parts you carry. So I would guess that you only have to think that you're a girl and WHOOSE...you ARE a girl, as far as anyone dare ask. The white.black thing seems to be a very sensitive topic. I'm guessing it won't work the same way and you'll probably get the crap kicked out of you if you make a claim to be anything other than what you are. Check with Elizabeth Warren just to play it safe.