Our initial search identified 148 publications. Out of these studies, we identified 54 studies that included 40,749 subjects meeting criteria for inclusion (Table 1). We found strong evidence that 5-HTTLPR moderates the relationship between stress and depression, with the s allele associated with an increased risk of developing depression under stress (p=0.00002). The significance of the result was robust to sensitivity analysis, with the overall p values remaining significant when each study was individually removed from the analysis (1.0E-6<p<0.00016). In addition, when we restricted our analysis to those studies with a study “quality” score above the median, the p value remained highly significant (3.2E-10, N=14).
