Using two dfferent models of atherosclerosis (ApoE KO and LDLR KO), previous studies have shown that PECAM exhibits site-specific behavior in the formation and development of atherosclerosis, such that PECAM promotes atherosclerosis in the aortic arch while it prevents atherosclerosis in the descending aorta42, 43, 44, 45. The gene discussed is APOE; the disease is atherosclerosis.