The researchers linked 33,129 CpG sites to PTSD diagnosis, including DNA methylation at two sites in NR3C1 and two additional sites in FKBP5. Interestingly, DNA methylation at 16 CpG sites in NR3C1 and four sites in FKBP5 in paternal sperm were associated with a reported mental health diagnosis in offspring. The gene discussed is FKBP5; the disease is post-traumatic stress disorder.