title: Novel duplication in the F12 gene in a patient with recurrent angioedema.
abstract: Edema formation is mediated by histamine or bradykinin release and may have several hereditary and acquired causes. In hereditary forms of bradykinin-mediated angioedemas, mutations in the genes encoding C1-inhibitor (SERPING1) as well as coagulation factor XII (F12) have been described. We present a novel F12 gene mutation, a duplication of 18 base pairs (c.892_909dup) in a 37-year-old woman with recurrent angioedema and normal C1-inhibitor level. A single episode of facial edema in the family of the patient showed co-segregation with the mutation. This duplication is causing the repeated presence of 6 amino acids (p.298-303) in the same region of factor XII, as those three mutations described previously in cases of hereditary angioedema with normal C1-INH function. These results may confirm the importance of the proline-rich region of factor XII protein in edema formation.
authors.affiliation: 3rd Department of Internal Medicine, Semmelweis University, Budapest, Hungary.
authors.forename: Nóra
authors.initials: N
authors.lastname: Kiss
authors.forename: Eszter
authors.initials: E
authors.lastname: Barabás
authors.forename: Katalin
authors.initials: K
authors.lastname: Várnai
authors.forename: Adrien
authors.initials: A
authors.lastname: Halász
authors.forename: Lilian Ágnes
authors.initials: LÁ
authors.lastname: Varga
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Prohászka
authors.forename: Henriette
authors.initials: H
authors.lastname: Farkas
authors.forename: Ágnes
authors.initials: Á
authors.lastname: Szilágyi
mesh_terms: D000328:Adult; D000799:Angioedema / Q000097:blood / Q000235:genetics*; D050718:Complement C1 Inhibitor Protein / Q000032:analysis; D003181:Complement C4 / Q000032:analysis; D005174:Factor XII / Q000235:genetics*; D005260:Female; D006801:Humans; D009154:Mutation; D012008:Recurrence
chemical_list: D050718:Complement C1 Inhibitor Protein; D003181:Complement C4; D005174:Factor XII
keywords: Angioedema; Factor XII; Mutation