FKBP5 and depressive disorder: Furthermore, the FKBP5 rs3800373 variant is located in the 3′ prime untranslated region and likely alters the stability and half-life of the mRNA and modulates glucocorticoid signaling and HPA axis function (Fudalej et al., 2015); this variant has been linked to symptoms directly associated with sleep disturbances such as anxiety, depression and pain (Knisely et al., 2019).