SLC6A4 and post-traumatic stress disorder: The two goals of this study were, first, to investigate whether findings from previous reported intervention-associated candidate genes (NR3C1, FKBP5, SLC6A4, Oxytocin Receptor (OXTR) could be replicated reducing confounding effects in a female-only PTSD cohort, and, second to identify new differentially methylated regions (DMRs) by performing an exploratory whole-genome bisulfite sequencing (WGBS) in a sub-sample of the PTSD cohort.