Is there a Gay gene?

[tooblue]

"Since sexual orientation is such a complex trait, we're never going to find any one gene that determines whether someone is gay or not," says Mustanski. "It's going to be a combination of various genes acting together as well as possibly interacting with environmental influences."

Previous studies in male twins have suggested that between 40%-60% of the variability in sexual orientation is due to genes. The rest is thought to be due to environment and possibly other biologic but nongenetic causes.

http://www.webmd.com/sex-relationshi...there-gay-gene

What happens if someone has such a genetic makeup but due to 'possibly other biologic but nongenetic causes' is not gay ... must that someone accept that he/she is gay and embrace homosexual behavior, because obviously 'choice' is not a variable?