This study is nearly a year old. Even at that, it is not an example of the first eidence that ADHD is a genetic disorder. There's at least one other study from

This study is nearly a year old. Even at that, it is not an example of the first eidence that ADHD is a genetic disorder. There's at least one other study from 2009 (http://www.research.chop.edu/publications/press/?ID=475 http://www.research.chop.edu/publications/press/?ID=475) that had similar evidence.