Subject: A question concerning human genetics.

I once heard a genetic scientist say that the idea of one gene  
controlling one specific trait is false. Instead, he said, most
inherited traits in humans are the result of an interaction or
collaboration between several genes, and each of them plays
a part in several such interactions, with a new and different
function every time. I have not been able to confirm this in
literature. Could you tell me if this is true and, if so, how usual
this interaction is - do most  human genes work this way or
just a few? If you could also give me a couple of titles of
books that explain this, I'd be very grateful.

Re: A question concerning human genetics.