In my opinion, homosexuality may be cause be several factors:
1) Emotional trauma- child abuse, neglect, sexual assault, etc. These things injure our spirit and may twist our mental wiring to the extent we misplace our affections. We are in fact sensual creatures (Freud said so). So it makes sense that we should have sexual feelings towards other human beings. Emotional injuries may condition some people toward members of the same sex;
2) Chemicals and toxins. Studies have shown that plastics and other chemical compounds leaking into our food may affect the production of testosterone. This may even occur when still in the womb. Microwaving food in plastic containers is a major cause. So is drinking water stored in plastic bottles for long periods, especially if it's been sitting in the hot sun or shipping container before ending up on a store shelf somewhere.
I read somewhere that one sign of a young boy growing up to be gay is if his ring finger is equal to or longer than his middle finger. I found this to be true in one instance where an effeminate boy in my church had a longer ring finger. A longer ring finger supposedly indicates a lack of testosterone. This boy also grew up on processed foods and used the microwave oven a lot, being raised in a dysfunctional home. His mother was mentally disturbed and had a history using drugs.
3) Demonic spirits. There are spirits of homosexuality that shape, form and influence people's minds and bodies to be gay, just as easy as a demon making a person angry or engage in other undesirable behavior.
There are times when I can literally feel the homosexual spirit emanating from a person. Sometimes, I don't even have to look at a stranger to know he/she is gay. If the spirit is strong, I can feel it. This happened to me a few times. This is very similar to how I feel and discern spirits. People can be delivered from these spirits if they submit themselves to repentance, prayer and fasting, if necessary.
One of the observations I've made over the years is that some gay men have physical facial features that give them away. It's usually in their eyes and eyebrows. To me, it is neither masculine or feminine, but rather wicked and perverted. With that said, I'm inclined to believe their homosexuality is demonically driven by spirits of perversion.
Jesus is the only one who can deliver and heal homosexuals and transform people's lives in the deepest sense. The problem is getting them to this point.