In this report, we reveal the attenuated formation of ballooned platelets coupled with increased formation of a distinct procoagulant CSNB platelet phenotype in the hemostatic response of platelets of members of the original Montreal platelet syndrome (MPS) kindred with von Willebrand factor (VWF) p.V1316M mutation6,7. Here, VWF is linked to mucopolysaccharidosis.