Currently, three C1INH preparations are approved for the treatment and/or prevention of HAE, two plasma-derived, pasteurized, and nanofiltered (pdC1-INH, Berinert® and Cinryze®), and one recombinant product [rhC1-INH, Conestat alfa (Ruconest®), derived from the breast milk of transgenic rabbits]. Here, SERPING1 is linked to hereditary angioedema.