Substance abuse - latest research with twins

I don't think I have ever spoken with anyone who does not know first-hand of a substance abuse problem, either in their own family or someone they might have known. Like the weather, everyone has something to say, but after a while we all come to the same conclusion: We can talk about it til the cows come home, but there really isn't a lot we can do about it.
Only when the affected individual gets to that critical point - and no one knows how to make that happen - will he or she have any chance of slaying their demon.

From American Scientist, this is a report from the famous twins study in Minnesota.

Our study of addictive behavior is part of a larger project, the Minnesota Center for Twin Family Research (MCTFR), which has studied the health and development of twins from their pre-teen years through adolescence and into adulthood. Beginning at age 11 (or 17 for a second group), the participants and their parents cooperated with a barrage of questionnaires, interviews, brainwave analyses and blood tests every three years. The twin cohorts are now 23 and 29, respectively, so we have been able to observe them as children before exposure to addictive substances, as teenagers who were often experimenting and as young adults who had passed through the stage of greatest risk for addiction.
[...]
This article reviews some of what we know about the development of addiction, including some recent findings from the MCTFR about early substance abuse. Several established markers can predict later addiction and, together with recent research, suggest a provocative conclusion: that addiction may be only one of many related behaviors that stem from the same genetic root. In other words, much of the heritable risk may be nonspecific. Instead, what is passed from parent to child is a tendency toward a group of behaviors, of which addiction is only one of several possible outcomes.

No, it doesn't make excuses. This is nothing more than a group of researchers publishing a paper. It would be wrong and mean to conclude that the people we love who may be trapped in a cycle of addictive behavior are fated to stay that way. This report changes nothing, but it does add to the already heavy portfolio of data we already have.

If you know someone with a substance abuse problem, you need to read this. It won't change the problem. But it might add to your understanding.