Is there anything like a curse on some people?

I was having a debate with one of my friend on whether God exists, and I was in support of this statement.. Then he asked if there is a real God, then why there is so much differentiations without any deed they have done.. For instance many babies are born with disabilities and some people are born with homosexual genes, so how can they cure themselves, because it is by birth, and not a psychological disorder. As I an from a Hindu background, and I just received Lord Jesus as my Savior, (not having sufficient knowledge of bible to answer him). So can someone suggest me some verses on bible which says about these things....