Brain Rules for Baby: How to Raise a Smart and Happy Child from Zero to Five

by John Medina

The gene 5-HTT, a serotonin transporter gene, may partially explain the difference. As the name suggests, the protein encoded by this gene acts like a semitruck, transporting the neurotransmitter serotonin to various regions of the brain. It comes in two forms, which I’ll term “long” and “short” variants. If you have the long form of this gene, you are in good shape. Your stress reactions, depending upon the severity and duration of the trauma, are in the “typical” range. Your risk for suicide is low and your chance at recovery high. If you have the short form of this gene, your risk for negative reactions, such as depression and longer recovery times, in the face of trauma is high. Interestingly, patients with this short variation also have difficulty regulating their emotions and don’t socialize very well.