These include emphysema (SERPINA1 mutation) (11), thrombosis (SERPINC1 deficiency) (12), hereditary angioedema (SERPING1 deficiency) (13), cirrhosis (SERPINA1 polymerization) (14) and Alzheimer’s disease (SERPINA3 polymorphism) (15). The gene discussed is SERPINA1; the disease is hereditary angioedema.