Scott syndrome is a rare autosomal recessive congenital bleeding disorder caused by a defect in blood coagulation. When platelets are activated, a calcium-induced rearrangement of the platelet membrane phospholipids takes place, exposing negatively charged phosphatidylserine (PS) at the outer surface of the platelets, where it can anchor coagulation factors. This phenomenon is mediated by lipid scramblase. In patients with Scott syndrome this mechanism is defective, resulting in impaired blood clotting. A mutation in the gene encoding scramblase TMEM16F has been found.
