Serotonin transporter gene polymorphisms and mental health

Purpose of review The serotonin transporter gene, SERT, is perhaps the most studied candidate gene in the field of psychiatric genetics, with several dozens of studies published during the last year. This review summarizes the recent findings regarding the gene in various psychiatric disorders and discusses some of the studies investigating other aspects of the phenotype such as personality traits. Recent findings A number of unsuccessful attempts to replicate associations between SERT polymorphisms and disorders such as depression, obsessive-compulsive disorder, and eating disorders have been published. In addition, interesting findings regarding the possible role of these polymorphisms in attention deficit hyperactivity disorder have been presented. Further support for an association between SERT polymorphisms and anxiety-related personality traits in the normal population have been reported, and further substantiated by the intriguing finding that this gene influences cerebral blood flow in response to fearful stimuli. Moreover, recent studies have provided further support for an influence of SERT polymorphisms on antidepressant response. Summary Whereas studies regarding a possible association between SERT polymorphisms and various psychiatric disorders responding to serotonin-acting drugs have been mainly negative, a previously observed association between this gene and anxiety-related personality traits has been confirmed in several reports. One interpretation of these findings would be that serotonergic transmission does indeed influence anxiety and mood, but that the functional consequences of the studied polymorphisms in SERT are insufficient to cause depression or anxiety disorders; in contrast, they may be of sufficient significance to influence more subtle aspects of behavior.