Figure 1.

Summary of the study designs for the three genome-wide association studies of antidepressant treatment response published to date. The details of each GWAS are included, with population ancestry, study size, antidepressant treatment used, treatment response time and outcome measure [5,9,13]. The differences between studies may play some role in the lack of overlap in results between studies, although a more major factor is likely to be limitations in statistical power to detect smaller genetic effects. GWAS, genome-wide association study; HAM-D, Hamilton Depression Rating Scale; MADRS, Montgomery-Asberg Depression Rating scale; QID-SR, Quick Inventory of Depressive Symptomatology Self-Report version.