Where does the Gay accent come from?

There is no place with such a density of gay men that they all learn to talk the same way (except maybe a Catholic seminary), so where do those nasal, over stressed vowels come from? It ain't no secret code if we can all hear it. I heard the accent before there was the LOGO channel so people didn't pick it up from TV. I don't for a second believe it's genetic, and since I can fake the accent, I know most gay men could turn it off if they wanted to, so what's the deal? Is it some wanna-be New Yorker thing? Or is it just a way of saying, "Ha-Aaaay, honey bee! My nectar is reeeeelly sweeeeet."