ABO and Stroke: Genome-wide association studies (GWAS) have identified many loci associated with vascular risk factors (VRFs) and ischemic stroke (IS) risk, including some stroke-cause specific genes such as alpha 1-3-glactosyl-transferase (ABO), which is suggested to be a risk gene for large vessel disease (LVD) and cardioembolism (CE) causes of IS (1), yet whether these genes also play a direct role in post-stroke pathology which might identify them as potential targets for stroke treatment, is not well-understood.