You know what? I'm sorry, I didn't state exactly why I had a problem with your words on the front end. My bad. I'm not saying "YOU" personally are a bad person. Your intentions are innocent. Many people will reasonably take your words to have an improper motive when you use the word "normal" in the way there you were using it. After a few posts, I can see you aren't coming from a place of negativity, but I wanted to make you aware of how it can appear. Because your average person doesn't use the word "normal" in the same way you do.
Yes all of those things are caused by genetic mutations. Like
Helios
said above I think the better word to use would be "majority" and "minority". People that have red hair, gay or lesbian, left-handed, etc are in the minority. But they are still normal human beings.
Us right-handed, black-haired, straight people are in the majority. Those characteristics don't make us the "normal" humans lol.