Sexual performance problems, such as impotence and...

Sexual performance problems, such as impotence and frigidity, are 70 to 90 percent changeable. But a homosexual who wants to be a heterosexual - that's close to unchangeable. And a transsexual - say a man who believes he's really a woman in a man's body - is completely unchangeable; you'd have to change the body to conform to the psyche.