Effectively, not the PBMCs synthesis of C1-INH mRNA, nor that of other molecules classically implicated in the pathogenesis of HAE like Angiotensin Converting Enzyme (ACE), Bradykinin Receptors 1 and 2, (BDKR1, BDKR2) or Aminopeptidase P (APP) showed any statistical effect on the frequency of HAE attacks [18,19]. This evidence concerns the gene BDKRB1 and hereditary angioedema.