PTSD is accompanied by low-grade inflammation that is associated with methylation of inflammatory genes (glucocorticoid receptor, TLR2, ICAM-1, inducible NOS, interferon-γ, and interleukin-6) [78,79], and long-term changes in circulating pro-inflammatory cell numbers [80,81,82]. This evidence concerns the gene NR3C1 and post-traumatic stress disorder.