We tested for significant associations of common genetic variants of NOTCH1–4 (investigated by microarray) and genomic methylation of saliva‐derived DNA with lifetime PTSD risk in independent cohorts from Northern Uganda (N1 = 924) and Rwanda (N2 = 371), and investigated whether NOTCH‐related gene sets were enriched for associations with lifetime PTSD risk. This evidence concerns the gene NOTCH1 and post-traumatic stress disorder.