This was in line with a study in the Saudi population, in which protein S deficiency was the most dominant form of thrombophilia (14.5%), whereas prothrombin gene mutations and FVL mutations were the least common cause for thrombophilia (in 1.1% and 0.5% of patients, respectively) [13]. The gene discussed is PROS1; the disease is hyperinsulinemic hypoglycemia, familial, 4.