Factor Xii Deficiency

Factor XII deficiency is an inherited disorder that affects a protein (factor XII) involved in blood clotting. While a lack of factor XII does not cause affected individuals to bleed abnormally, the blood takes longer than normal to clot in a test tube. The condition is usually discovered when prolonged clotting is noticed in the process of running other laboratory tests. Factor XII deficiency is caused by mutations in the F12 gene. It is inherited in an autosomal recessive manner.