CXCL1 and post-traumatic stress disorder: PTSD associated with: (1) ↓ methylation of TPR and ANXA2 and ↑methylation of CLEC9A, APC5, TLR8 in PTSD; (2) ↑methylation of BDNF and CXCL1; (3) 19 of 54 of the differentially methylated immune-related genes examined in Uddin et al. (2010)