It might be genetic and it might be anything else. It might just be dumb luck. We should expect this sort of thing to happen to people based on pure randomness

It might be genetic and it might be anything else. It might just be dumb luck. We should expect this sort of thing to happen to people based on pure randomness alone. You should never expect to win the lottery. But you should expect _someone_ to win very often. If you were to win, it wouldn't be evidence that you somehow are luckier than others.