Homosexuality is caused by an unclean spirit, it's that simple. This is why gay people say that they didn't choose to be gay, and this is why they think they were born that way but they weren't. A homosexual spirit can attach itself to a kid as young as 1 or 2 years old and all their life from childhood they will exhibit homosexual tendencies or traits before they even know what it is.
People can also pick up a homosexual spirit by hanging out with other gays and experimenting with same sex.
Homosexuals need prayer and deliverence and only God can deliver them from that. It is unnatural and a devience from how God intended sex to be. Homosexuality greatly displeases God.