BDNF and post-traumatic stress disorder: In non-smokers with PTSD, BDNF rs6265 genotypes (H = 0.869; df = 2; p = 0.647), dominant (U = 3262.0; p = 0.495) or allelic (U = 8681.5; p = 0.424) models were not significantly associated with the PANSS cognitive subscale scores (Figure 2, Supplementary Table S2).