VWF and von Willebrand disease 1: Emergent endoscopic findings did not support technical complications (e.g., clip dislodgement) as the primary etiology of the post-polypectomy hemorrhage.Genetic testing identified a mutation in the von Willebrand factor (VWF) gene [c.1707(exon14)delC, heterozygous], leading to a diagnosis of type 1 von Willebrand disease, which subsequently led to the unexpected post-polypectomy bleeding.