I only know of one experiment on this: < http://en.wikipedia.org/wiki/Rat_Park http://en.wikipedia.org/wiki/Rat_Park >. It concluded that morphine addiction in

I only know of one experiment on this: < http://en.wikipedia.org/wiki/Rat_Park http://en.wikipedia.org/wiki/Rat_Park >. It concluded that morphine addiction in ordinary rats is not just influenced by their environment, but pretty much determined by it. I'd be interested to hear how much that can be changed by breeding the rats selectively. Until you know that, I won't believe anything you say about genetic influences on addiction. It seems that no one has tried to find out. So I assume that Addiction Studies (or whatever it's called) has very little to do with science.