You guys
do know that DaVinci was officially charged with sodomy when he was in his late teens or early twenties? --held pending legal
action for about 2 months--after which he was released due to lack of witnesses (as if there would be witnesses!

). A couple of other guys were
also charged in the same incident.
I'm not saying he was definitely a homosexual - it remains officially undetermined and no one ever really said for sure, all through history. But
his relationships, liasons, and even the nature of his artwork seem to show quite a bit of support for the possibility.
Also, in the time he lived, artists were absolutely forbidden to use women as models--nudes or not. So all women that were painted by the likes of
DaVinci, Michaelangelo, and Raphael, were actually structured upon the sketches of their nude male models, then draped with clothing and made into
females in the finished creation. That's why the women (especially in the sistine chapel) are usually quite robust farm-healthy looking girls (often
called 'rubenesque').
Trying to figure out the gender of the subjects painted in this masterpiece and how it might relate to various religious convictions - by analyzing a
work of art created in Renaissance Italy by an enigmatic and eccentric genius that was very likely a homosexual is definitely a futile approach to
getting to the bottom of this issue (if there is indeed a bottom).
There are many more sketches available online, along with his notations, that can solve this question without too much sleuthing.

As well as
provide insight into the motives of his art which might bring a new understanding to the mix.