I agree with this, I don't believe there is a "religiosity gene" that depicts whether someone will be religious or not. Following a belief system is a completely subjective decision. Some people may be brainwashed from birth, which could cause them to devoutly follow the religion for the rest of their life, but there isn't genetic programming that predetermines this or even a gene that makes someone more inclined to be religious. I also believe that organized religion is decreasing in popularity due to increased globalization. As the world becomes more globalized and people are exposed to different cultures, beliefs, and religions, people get many different perspectives that may modify or completely change their own beliefs. Changing ones beliefs is not a part of organized religion and therefore will turn people away from it.