To better understand the effects of d-flow alone, hypercholesterolemia alone, and d-flow under hypercholesterolemia on EC population change during atherogenesis, 5 EC clusters expressing canonical EC markers (Pecam1, Cdh5, Icam2, and Tie1) were further analyzed in depth (Figure 2A). This evidence concerns the gene PECAM1 and familial hypercholesterolemia.