Discovering SERPING1 variations in C1-INH-HAE patients and reporting data that contribute to the correct interpretation of the pathogenicity of these variations are of utmost importance since knowledge of the genetic background may support the establishment of the correct and early diagnosis of C1-INH-HAE promoting the patient's proper treatment, prognosis, and quality of life. This evidence concerns the gene SERPING1 and hereditary angioedema.