This is in line with the clinical studies in combat veterans with PTSD and non-veterans with anxiety and aggression that documented abnormal pro-BDNF/BDNF ratio, likely due to p75NTR upregulation (Matsuoka et al., 2015; Ilchibaeva et al., 2018; Kowiański et al., 2018). This evidence concerns the gene BDNF and post-traumatic stress disorder.