FKBP5 and post-traumatic stress disorder: Mirroring these alterations, variants of the FKBP5 gene have been identified in human studies as biomarkers for stress-related disorders, such as anxiety, depression, and PTSD (Maul et al., 2020; van Zuiden et al., 2012; Michopoulos et al., 2015; Binder et al., 2008; Castro-Vale et al., 2016).