Several other genes were discovered to be associated with PTSD and replicated in the largest available independent PTSD-informative dataset, the PGC-PTSD GWAS13. Included among these were TSNARE1 (T-SNARE Domain Containing 1) and EXD3 (Exonuclease 3’−5’ Domain Containing 3). TSNARE1, the product of which is involved in intracellular protein transport, has been associated with risk-taking54, which may predispose to PTSD through increasing the likelihood of exposure to traumatic events; twin studies suggest that risk for exposure to traumatic events is partially heritable5. EXD3, the product of which is involved in nucleic acid binding, has been associated with mathematical55 and other cognitive abilities, which have been found in our study and others to be genetically negatively correlated with PTSD and mediated by socioeconomic status56. The MVP/PGC case-control meta-analyses also identified associations with PARK2 and PACRG, both of which are associated with susceptibility to leprosy and to intracellular pathogens57. It remains to be determined to what extent these associations reflect systems or processes that underlie PTSD pathophysiology, but we now have gene candidates discovered and replicated through unbiased searches that can be further
