I think there must be some form of association between exposure to certain environmental conditions, wether prenatal or after, that would alter brain plasticity. Having same-sex attractions exclusively makes made me think of it for so long. I think intestinal parasites has some role to play in that process. I am smaller, softer than my siblings in demeanour and voice which makes me think it affected my growth and so my puberty. Sexuality is a complex issue and I don't think in all cases of gay people you would find the same admixture of reasons what made them that way. In my case I think my lesser growth resulted in me perceiving myself as more like psychological female. It is not that i think of myself as a woman but more like i am fine in my own male skin but i think and feel like a woman. I think that naturally made me gravitate towards completing what I feel missing from my masculinity by searching for it in other more dominant guys. It is an issue for me because my personal beliefs are totally against gay lifestyle although for years i have tried it and it didn't work for me.