In the present study, we report 10 consecutive cases of C1-INH-HAE patients affected by mild to moderate chronic periodontitis, and thus requiring periodontal therapy.20,31,43 The patient sample is sufficiently representative, considering the estimated prevalence of HAE in the global population48; this is of particular interest, since seven patients were affected by type I C1-INH-HAE and three patients by type II C1-INH-HAE. The gene discussed is SERPING1; the disease is periodontitis.