Surpisingly the NIDA says "addiction" is a genetic disease triggered by environmental factors. They had to be dragged kicking and screaming to this conclusion. It was pretty much established science by the time they allowed as how it might be true.

Here is what they have to say:

Evidence from adoption and twin studies and from animal models suggests that vulnerability to addiction has a moderate to high heritable component. The gene variants underlying increased vulnerability to addiction are unknown, but new advances in science and technology will facilitate the identification and characterization of these gene variants. Like many other psychiatric illnesses, drug abuse and dependence comprise a complex set of genetic disorders lacking a simple pattern of Mendelian inheritance. Multiple genes with relatively small effects are likely to influence vulnerability to addiction, gene x environment x development interactions appear to play significant roles in mediating outcomes, and there may be no simple correspondence between current phenotypes and the genotype(s). Therefore, a broad range of scientific approaches will be needed to elucidate the role and identity of genetic factors in drug abuse vulnerability.

It is pretty well established (at least anecdotally) that besides a genetic base, addiction requires an environmental trigger. It appears that that trigger is trauma that generates an intense emotional reaction.

Here is one anecdote that I recieved today at my blog:

I was a heavy user of hard drugs for a long time, and know many people in the situation. Having some sort of unpleasant past or fractured personality was an almost universal factor- long before most of these people ever started using drugs- physical detox fails because leaves underlying psychological factors intact (in many cases I don't think people can ever really be "cured" anyway). The war on drugs has made criminals people who are mostly either looking for relaxation/stress relief, or escaping some form of psychic torment. oh- Literally every female junkie I've met had either been raped or molested.

Is Addiction Real?

This fits in well with the work of Dr. Lonnie Schavelson who wrote a book on his findings.

Social studies of actual users could put definitive numbers to these anecdotes.

Are any such studies being done in conjunction with the genetic studies?

Cross Posted at Power and Control