As for the "addict gene", again, this was supposed to be a synonym phrase for a notion of hereditary weakness, I was not implying it has a genetic basis or that genetics was known before Crick. The phrase "addict gene" was quoted because I have heard it in Sweden (in modern times) when discussing these issues.
I'm hardly an expert on Swedish history, just a person who asks questions when I travel. What I know of Swedish history could be written on the back of a postage stamp. I'm afraid I wasted more time on Roman history in school (as you can imagine, Swedish history doesn't come up very often).