Other studies point out that stress-associated epigenetic changes in the human glucocorticoid receptor gene (NR3C1) [23,24], human serotonin transporter gene (SLC6A4) [25,26], brain-derived neurotrophic factor gene, (BDNF) [27], FK506 binding protein 5 gene (FKBP5) [28], and spindle and kinetochore associated complex 2 gene (SKA2) [29], were found to be associated with a diagnosis of MDD. This evidence concerns the gene BDNF and major depressive disorder.