FKBP5 and major depressive disorder: While genetic variations in NR3C1, NR3C2, CRH, CRHR1, and BDNF have also been shown to be involved in conferring risk to SRDs (see reviews (Ebner and Singewald, 2017; Plieger et al., 2018; Chen et al., 2006)), in vitro studies in this field have primarily focused on FKBP5. Additionally, Arloth et al. (2015) demonstrated that common genetic variants associated with MDD and schizophrenia modify the transcriptional responsiveness of GR target genes (Arloth et al., 2015).