The serum fetuin-A has not been investigated in C1-INH-HAE; however, these structural similarities of fetuin-A with C1q and HMWK, which have important role in the pathomechanism of C1-INH-HAE and as fetuin-A is a negative acute phase protein may influence the development of HAE attacks. The gene discussed is AHSG; the disease is hereditary angioedema.