Mutational spectrum of the SERPING1 gene in patients with hereditary angioedema

Hereditary angioedema due to the C1-inhibitor deficiency (Type I) or the dysfunction (Type II) is a rare genetic condition characterized by recurrent episodes of edema with an estimated frequency of 1:10 000 and 1:50 000 in the global population without racial or gender differences. HAE Type III is even less common, and unlike Types I and II, it does not appear to be connected with the levels of the C1-inhibitor. For 45 patients (64.44% female; 35.56% male) from 19 unrelated families C1-INH-HAE was confirmed. A series of 19 different mutations in the SERPING1 gene was identified: 17 splicing (37.7%), 15 missense (33.3%), 8 frameshift (17.8%), 3 large del (6.7%), 2 nonsense (4.5%) mutations were found. De novo mutations were detected in 8 patients (17.78%). For 6 patients, the HAE diagnosis was determined at the pre-symptom stage. 9 C1NH mutations had not been previously described. The number of different mutations identified highlights the heterogeneity of the C1 inhibitor deficiency.