Genetic analysis of the described patients. (A) Pedigree of the 2 families. (B) Histograms from the patients sequencing with indication of found mutations. (C) Localization of mutations within the factor B gene (rectangles represent exons; line represents introns) and within the protein sequence (the 3 domain types—CCP [complement control protein], VWFA [von Willebrand type A], and serine protease are indicated). Numbering is made with the first methionine referred as 1 (as described in Hourcade et al13 ).