Is homophobia a genetic predisposition?

I was reading this Daily Telegraph article shared by someone on Facebook, and in the tangle of comments this question was one of those posed: "Were you raised to be homophobic or is it a genetic predisposition?" Whatever was intended, this question raises a significant issue. So what if homophobia is a genetic predisposition? One of the main arguments voiced in support of acceptance of homosexuality is the "fact" of genetic predisposition. How can you discriminate against the way someone was born?

But what if homophobia were also a genetic predisposition? What if, in the same way someone is "hard-wired" to be attracted to someone, another person is similarly predisposed to be repulsed by another? Is it legitimate to discriminate against their phobia? And if not, why not? On what basis do we decide what is right or wrong? Is it popular opinion? Or historical precedent? Is it majority current opinion, or majority historical opinion? Or what..?

Of course, this is a little facetious. And I'm not really wanting to comment on whether homosexuality or homophobia is a genetic predisposition. But in seriousness, I think it does highlight a key problem in the whole question. It is not so much the danger of the slippery slope, but more-so the danger of being floating adrift in a sea of moral uncertainty, blown about by every new wind, and perhaps with the only certainty being that one day we will sink beneath the waves completely.

As a Christian, I know that God has spoken into his world, to give us an anchor, and solid ground. While so many may opine that it is ridiculous and antiquated, even bigoted, to hold to the Bible as the Word of God, just because that is their opinion, it doesn't make them right.