I don't believe people are born gay. One of my best friends growing up has struggled with homosexuality. He didn't start liking men until the idea was impressed upon him by people telling him he was gay. Now, he considers himself straight, but he is in love with a man, and says this is the only man he would be gay for. I also don't believe people are born with sloth, or lust, or gluttony, or any of the others, but that our environment does shape us to have these qualities. If we find ourselves overcome with sloth, we can work above it and push ourselves to exercize or be less lazy. If we find ourselves having feelings for people of the same gender, we can overcome that by ignoring those feelings.
Some of my best friends say they are gay, but honestly, I don't believe them. I think part of it is for attention, part of it is because they were called gay so much they started believing it, part of it is they fell in love with the personality of someone of the same gender and confuse it with lust and sexuality. Some people can look at someone of the same gender and say, "Wow, they are really handsome/beautiful", appreciate that person's looks, and move on. However, there are those who think to themselves, I find that person attractive, does that mean I'm gay?
God promised us he would never give us more than we could handle, he would never put an obstacle in our path that we couldn't overcome with His help. I think homosexuality is just one of those obstacles. Mind you, I'm an Episcopalian, a religion who is known for it's tolerance for homosexuality to the point we even have an openly gay bishop. I still think it's wrong to be gay, but I don't think you are condemned if you are. I would rather we let openly homosexual people into our churches, teach them the same as we would teach or allow any other sinner, not make them feel outcast because of their sin, but a part of the family, and help them repent rather than call them abominations or shun them. God asks us to love, not judge.