Quebec platelet disorder (QPD) is an autosomal dominant bleeding disorder linked to a region on chromosome 10 that includes PLAU, the urokinase plasminogen activator gene.
In QPD megakaryocytes, cultured without or with plasma as a source of plasminogen, alpha-granule proteins were stored undegraded and this was associated with much less uPA-plasminogen colocalization than in QPD platelets.
During clot formation, the urokinase plasminogen activator released by QPD platelets leads to platelet-dependent increased fibrinolysis, and this is postulated to be a major contributor to QPD bleeding.