ADAMTS13, which cleaves unusually large (and hyperreactive) von Willebrand factor (ULVWF) released from activated endothelial cells to smaller and less active forms, is a metalloproteinase involved in von Willebrand factor coagulation and platelet activation pathways, and is possibly related to the vasculopathy and endotheliopathy present in SSc 23,24. This evidence concerns the gene ADAMTS13 and vascular disorder.