The present invention provides methods and kits for identifying clinical trial responders from a placebo group in clinical trials for treating depression and/or major depressive disorder (MDD). The present invention further provides methods and kits for treating depression and/or MDD in an individual, and for identifying the likelihood that an individual suffering from depression and/or MDD will respond favorably to administration of a placebo and/or experience an enhanced placebo effect when administered a placebo. These methods and kits comprise determining the presence of polymorphisms in the Brain-Derived Neurotrophic Factor gene (BDNF), the B-Cell CLL/Lymphoma 2 gene (BCL2), and/or intergenic regions in an individual.
