Leiden thrombophilia is caused by mutational deficiency of which of the following factors?
Ref. Robbins Pathology. 9th edition. Page. 135
Factor V Leiden thrombophilia is an inherited disorder of blood clotting. Factor V Leiden is the name of a specific mutation (genetic alteration) that results in thrombophilia, or an increased tendency to form abnormal blood clots in blood vessels. Factor V Leiden is the most common inherited form of  thrombophilia.
FactorV
FactorVII
Factor IX
FactorX