Hereditary Angioedema (HAE) due to C1-esterase inhibitor (C1-INH) deficiency or dysfunction (C1-INH-HAE), is an autosomal dominant genetic disease characterized by recurrent cutaneous and submucosal swelling episodes most often caused by heterozygous pathogenic Single Nucleotide Variants (SNVs), small insertions or deletions (indels) or Copy Number Variants (CNVs) in the SERPING1 gene, coding for C1-INH. This evidence concerns the gene SERPING1 and hyperinsulinemic hypoglycemia, familial, 4.