KNG1 and hereditary angioedema: Genetic testing is often inconclusive; 8 mutations are so far known to cause HAE-nC1INH (aactor XII, angiopoietin-1, plasminogen, kininogen-1, myoferlin, heparan sulfate 3-O-sulfotransferase 6, carboxypeptidase N, and DAB2IP).