The incidence of acquired angioedema related to angiotensin-converting-enzyme inhibitors (ACEI-AAE) arising during treatment ranges from 0.2% to 0.7% and corresponds to a potentially substantial number of cases.1–3 For example, in France, 25% of the 12 million people suffering from high blood pressure and 40% of the 3 million diabetics take angiotensin-converting enzyme inhibitors, and there are 120,000 new heart attack cases every year.4–6 In a retrospective observational 5-year study in the United States, ACEI-AAE accounted for 4 of 10,000 visits to the emergency department (ED) each year.7 The gene discussed is ACE; the disease is acquired angioedema.