Does homosexuality have its beginning in childhood?

I think your example makes it sound as if there needs to be an explanation of a deviation from the norm in psychological terms, and I don't think that's so.  I personally think there's an immunological explanation in utero to do with elder male siblings.

It may not begin at conception as one person said because that would mean the combination of alleles from your two biological parents are alone responsible. However, genetics is not quite that simple. The way alleles function is affected by the environment in which they function. So, while the alleles are fixed at conception it is also more than likely to be a result of what happens during development in utero. So you cannot rule out 'in utero'. If you do that then you may as well end the discusiion. You cannot discuss something if someone is saying you cannot bring x,y or z into the discussion.

As both a biologist and a gay man I am convinced beyond all doubt that it is gentically based. No one in their right mind from my generation, and earlier ones, would have made it a lifestlye choice. All my gay friends of a similar age say exactly the same thing. We are just gay. We did not decide to be gay. We have no more choice in the matter than we had about the colour of our eyes, the texture of our hair, the oiliness of our skin, etc.

I never had that problem.

Girls were always chasing me, they loved me.

The problem is that I didn't love them. 

Sorry girls,  I'm gay.  

No.  

No one knows what is the driving force behind homosexuality. 

What we do know is many other animals and insects also enjoy a little same sex sex while other species do not have two sex or some that do have opposite sex reproduction methods but the species can play either roll.  

Yet mankind can not explain is why all these alterations to a simple need are so.

We believe sex is about reproducing yet we know in our lifetimes most sex is experienced for pleasure rather than seeking to reproduce,  which suggest we have the reasons back to front, its primary roll is pleasure with a side effect of reproduction.   

If it was that simple and obvious, it would have been a known fact centuries ago.

Despite everyone wanting to state that it is clearly this way or that, the actual fact is that no one knows how sexuality works...NO ONE.

We are a long, long way from ANY definitive study that explains to us what makes a heterosexual, or what makes a homosexual, or what makes anything else.

AND, a SECOND fact is that this lack of insight has NO significance, despite the fact that many (if not most) people who want to debate MORALITY (on EITHER side of the issue) have convinced themselves that it DOES.  It DOESN'T.

If I wish to have consensual sex with anyone of age, regardless of whether your faith considers that a sin or not, and regardless of whether you find the thought of my wish to be appealing or revolting, AND REGARDLESS OF WHY I WISH IT, it is fundamentally MY business and not yours...just as your sex is your business and not mine.

So battlelines drawn up on both sides of the "origin of sexuality" question are entirely illogical and wasted effort.  My advice to all of you is to forget about it, and never debate it one way or the other, again.  It entirely misses the point, which at the end of the day is a bedrock matter of equality and personal rights.

"Assuming we rule out the in utero thing"

Yes. Some people's sexual preference is clear years before they hit puberty

There is no real evidence that all gay people are born that way. Of course, the LGBT community must deny the effects of childhood experiences, social contagion and other environmental causes because that will delegitimize their movement.

Yes, it begins at conception.

No. Hide your trolling history, you level one oxygen thief