VKORC1 and chronic kidney disease: We aimed to investigate the association of the five common VKORC1 gene polymorphisms, −1639G>A (rs9923321), +1173C>T (rs9934438), +1542G>C (rs8050894), +2255C>T (rs2359612), and +3730G>A (rs7294), with arterial stiffness in CKD patients (Figure 1 illustrates the five SNPs within a 5 kb linkage disequilibrium block and their respective positions).