Missense mutations in the coagulation factor XII (Hageman factor) gene in hereditary angioedema with normal C1 inhibitor.
Hereditary angioedema is characterized by recurrent skin swelling, abdominal pain attacks, and potentially life-threatening upper airway obstruction. The two classic types are both caused by mutations within the complement C1 inhibitor gene. A recently described new type does not show a deficiency of C1 inhibitor and affects almost exclusively women. We screened twenty unrelated index patients with this new type of hereditary angioedema for mutations in the coagulation factor XII gene. Two different missense mutations were identified in exactly the same position within exon 9 of the F12 gene. 'Mutation 1' (1032C-->A), encountered in five patients, predicts a threonine-to-lysine substitution (Thr309Lys). 'Mutation 2' (1032C-->G), observed in one patient, results in a threonine-to-arginine substitution (Thr309Arg). The predicted structural and functional impact of the mutations, their absence in 145 healthy controls, and their co-segregation with the phenotype in five families provide strong support that they cause disease.
Dewald
Georg
G
Institut d'Immunologie et d'Hématologie, Faculté de médecine, Université Louis Pasteur, 4 rue Kirschleger, 67085 Strasbourg Cedex, France. Georg.Dewald@t-online.de
Bork
Konrad
K
D000799:Angioedema / Q000209:etiology / Q000235:genetics*; D050718:Complement C1 Inhibitor Protein / Q000235:genetics*; D005174:Factor XII / Q000235:genetics*; D005260:Female; D008040:Genetic Linkage; D006801:Humans; D008297:Male; D020125:Mutation, Missense; D010375:Pedigree
D050718:Complement C1 Inhibitor Protein; D005174:Factor XII