Current developments and controversies: does the serotonin transporter gene-linked polymorphic region (5-HTTLPR) modulate the association between stress and depression?

Human observational studies have shown that, in interaction with life stress, the short or S-allele of the serotonin transporter gene-linked polymorphic region (5-HTTLPR) is associated with an enhanced risk for depression. However, this gene-by-environment interaction (G×E) has recently been questioned by two meta-analyses. We aim to provide an overview and appraisal of recent developments and controversies.