The first 2 links are from Gene Edward Veith’s blog on the unlikelihood of homosexuality being genetic. Keep in mind (as he points out in the second post) that this does not necessarily mean that homosexuality is merely a “choice”; however, I would submit to you that even if some people have a “natural” inclination toward homosexuality, that does not make it any less of a sin. As a heterosexual male, I have a natural inclination to be attracted to every beautiful woman I see, but that does not make it any less of a sin for me to lust after those women or give into that natural inclination.
This final link/video is by one of my favorite Christian rappers & speaks to the fact that the Church (at least here in the U.S.) has tended to make homosexuality out to be a worse sin than any other–this is a blatant failure of the Church in America. God loved us when we were still His enemies (Romans 5:8); we should reciprocate that love toward those who are still living in sin-regardless of what for that sin takes.