The serotonin transporter linked polymorphic region (5-HTTLPR) is an important genetic variation that has been studied in relation to both the efficacy and side effects of serotonergic antidepressants. Before continuing to read this page, please read the basics on the following page: serotonin transporter linked polymorphic region (5-HTTLPR). For the association of 5-HTTLPR with the…