The results of this meta-analysis clearly demonstrate that stressful life events have a potent relationship with the risk of depression, an association that has been one of the most widely studied environmental factors for a range of mental disorders.8,9,44 Addition of the serotonin transporter genotype did not improve the prediction of risk of depression beyond that associated with exposure to negative life events. Prior studies45-48 have also raised concerns about validity of the claims of replication of the significant interactive influence of stressful life events on the association between 5-HTTLPR genotype and depression,49 and a recent meta-analysis using a different approach to that of the present study concluded that this association was compatible with chance findings.50
