Second, our GWAS analyses identified several genetic loci not previously associated with PTSD. These loci pointed to a number of different target genes that merit further investigation. With PARK2, there is a posited role of dopaminergic systems in PTSD. The dopaminergic system has a critical role in fear conditioning which is important in the development and maintenance of PTSD30. There is also epidemiological evidence for association of Parkinson Disease and PTSD31–33. PODXL is involved in neural development and synapse formation34, SH3RF3 is associated with neurocognition and dementia35,36, ZDHHC14 is associated with regulation of β-adrenergic receptors37,38, and KAZN is expressed in the brain39, where it has been found to be underexpressed in parvalbumin neurons of the superior temporal cortex of schizophrenia cases40 and overexpressed in the substantia nigra of Parkinson’s cases41. Finally, the HLA-B complex may be related through the known role of immunity and inflammation in stress-related disorders42,43. Less is known about the role of the identified RNAs LINC02335, MIR5007, TUC338 and LINC02571 in regards to the biology of PTSD. However, preliminary work from our group including imaging and psychophysiology
