As a devout Christian, who believes that Christ was born of a virgin, died on the cross with a purpose, and defeated death on the 3rd day, I firmly believe that being gay is a choice. And I believe it's wrong.
Down syndrome, mental disabilities, etc are a disease. Being gay is not a disease.
With that said, God made us with a soul to choose for ourselves. Whether we agree with choices are not, everyone should be allowed to make them. As well, we've prevented humans from fully enjoying the benefits of being an American based on many a things (gender, race, etc) all if which were wrong. Why is this any different? Because they're different?
Not to mention, Christ didn't run to the government to fix "problems". You want to see change? Be the change personally
It's definitely a touchy subject but can lead to some good debates. Sometimes.