In 429 male soldiers from the United States and the Netherlands, Katrinli et al. [16] identified cytosine-phosphate-guanine (CpG) sites near the genes F2R, CNPY2, BAIAP2L1, and TBXAS1 to be associated with risk of PTSD within military personnel prior to and following deployment. Here, CNPY2 is linked to post-traumatic stress disorder.