For example, PTSD and depression have been associated with DNAm changes in blood and buccal cells at genes involved in glucocorticoid functioning, such as the FKBP prolyl isomerase 5 (FKBP5) and the nuclear receptor subfamily 3 group C member 1 (NR3C1)15–19. Here, NR3C1 is linked to depressive symptom measurement.