Correlations involving BDNF were generally weak and negative across groups, with Glutamine–BDNF at ρ = −0.41 (p = 0.028) in No PTSD, ρ = −0.31 (p = 0.083) in PTSD ≤ 5 y, and ρ = −0.12 (p = 0.52) in PTSD > 5 y; Caspase-1-BDNF remained non-significant in all groups (ρ = −0.06 to −0.24, p > 0.20). This evidence concerns the gene BDNF and post-traumatic stress disorder.