Glucocorticoid regulation gene FKBP5 is differentially expressed in iPSC lines exposed to dexamethasone to simulate stress response. Heightened sensitivity to low levels of glucocorticoids is observed in iPSC lines derived from combat veterans experiencing PTSD, especially in mature neural cells as opposed to immature cells and NPCs. This evidence concerns the gene FKBP5 and post-traumatic stress disorder.