In contrast to various association studies that target variations in candidate genes, development of genome-wide association studies (GWAS) enabled an analysis of very large number of genetic variants in individuals with post-traumatic stress disorder (PTSD). Findings that include large datasets of both genders and different ethnicities, with detailed trauma type and timing, as well as PTSD phenotypic information, need to be further confirmed by mechanistic, structural, and functional data from animal and neuroimaging studies. Integrative approach based on systems biology might offer (epi)genetic panel that might be used for early prediction, detection of risk, differentiation of novel subtypes, and tailored personalized approach to PTSD prevention and therapy.