New Studies in Polymorphism Psychiatry: Focus on 5-HTTLPR

With the increasing sophistication and applicability of molecular genetics, researchers are uncovering new associations between specific genetic polymorphisms and psychiatric vulnerabilities. An area of particular interest in psychiatry is the promoter region of the serotonin (5-HT) transporter gene (5-HTTLPR), which contains a polymorphism with “short” and “long” repeats. The short variant leads to less transcription of the 5-HT transporter and lower expression of proteins thought to ultimately result in fewer serotonin molecules situated properly for optimal functioning. Since Caspi and colleagues’ seminal study associating the short allele with vulnerability in the presence of adverse life events for major depression, hundreds of studies…