I.. Don't get it.
Honestly. If you like someone, then you like someone, right? That means to complete picture. If you turn out to like someone you did not expect to like, then that's not their thing; it's yours. And you can either lie to yourself by blaming to other person, or you can accept that you're interested in that other person, and live with it.
That's my take on it, anyway. For instance: I'm usually not attracted to men. But at some point, I met some guy I actually secretly pined for. This was before I put a name to the whole gender thing, for me, but in my.. Well; thoughts on him, I always pictured myself as female. I can't say I had any erotic fantasies, but lots of romantic ones. Anyway; at that point, I just accepted that, somehow, I could be attracted to men. And shrugged. Of course; he was already taken, and never noticed me, but I guess every girl, and guy, knows how that feels.

So if you're a Genetic Male, and find yourself sitting in a classy restaurant with a trans girl, then just ask yourself: Do I like her, yes or no? But let's be honest: You'd ask yourself that question with any girl you go on a date with, right?