I don't know about the genetics part, but what I have noticed is that Jewish "leaf nodes" tend to be great mathematicians or otherwise intellectual. What I mean

I don't know about the genetics part, but what I have noticed is that Jewish "leaf nodes" tend to be great mathematicians or otherwise intellectual. What I mean by this is a child/person of Jewish descent, that is no longer religious and also does not have children. They are thus a leaf node in the tree. A current example would be Grigory Perelman. I don't like to conjecture about cleverness and intellegence and especially not genetics. But if there is one thing these Jewish leaf nodes have in common it is a really good education.