Overall Abstract The Psychiatric Genomics Consortium for PTSD (PGC-PTSD) is the largest international effort focused on understanding the genomic and epigenomic architecture of PTSD. We have now aggregated genomic data from over 50 studies, including ~20,000 PTSD cases and over 50,000 trauma-exposed controls of diverse ancestries and traumatic events to conduct well-powered genome-wide association studies (GWAS) of PTSD. By expanding on this initial effort, we have leveraged our organizational structure to move beyond SNP-based associations with closely connected working groups centered on CNV analyses, epigenetics, gene expression, and intermediate phenotypes such as neuroimaging, psychophysiology, and physical health. An overarching theme across working groups includes sex-specific differences in PTSD risk and vulnerability. This symposium will first present our current GWAS results from the PGC-PTSD freeze 2 that highlight the genetic vulnerability for developing PTSD following trauma exposure, including SNP-based heritability and genetic correlation across psychiatric disorders and other phenotypes / traits of interest. Next, we will present epigenome-wide effects on risk of developing PTSD across civilian and military cohorts. The second half of the symposium will focus on findings from intermediate phenotypes and anthropometric traits. Our third talk will present neuroimaging data that reveals smaller amygdala and hippocampal volume in PTSD, particularly when exposed to childhood trauma. Lastly, we will present analyses investigating the genetic overlap of PTSD with anthropometric traits and reproductive behaviors and functions in women, suggesting a putative causal relationship between genetically determined female body shape and PTSD. We will discuss our future strategies with a focus on harmonizing predictive variables such as trauma type, trauma severity, chronicity of exposure as well as outcome variables such as PTSD diagnoses, illness severity, and comorbid psychopathologies.