And just to confirm Buddha's observation of a strong genetic component to being a woolly woofter.
There may be a nurturing social element to being gay but I'm afraid there has to be a genetic predisposition if the social influence is to manifest fully into being a homosexual.
And as such, I think if you take your PC hat off ( I haven't got one of those) it has to be described as a genetic malexpression because it most certainly does not follow the normal criterion for long-term genetic success.
I never really understood the reluctance by some to embrace the notion of homsexuality being linked to one's genes, it's not as if it's anybody's fault or anything, nobody chooses to become gay any more than hetros choose to be straight....