You're saying race and sexual preference are the same thing, and I don't believe they aren't. People don't choose their race. They do, however, choose with whom and when they have sex, etc.
And before you say they can't help how they feel, I agree. But feelings aren't exactly where the sin comes into homosexuality. The feelings might be normal to some. Where the sin enters is when they choose to lust for or have sex with someone of the same sex. Just like the sin in my life wouldn't be my attraction to or feelings for a man, it would be in my choice to have lust for or sleep with this man.