Y. Jourdy and colleagues conduct analyses to characterize five genetic variations (three novels and two previously reported) localized in the FVIII B domain for their contribution to Haemophilia A (HA) phenotype. They concluded that FVIII B domain variants, p.D963N, p.S806T, p.G873D, p.H998Q and p.Q1225R may be considered as polymorphism or non-pathologic mutations.  In five patients, clinical phenotype could be explained by the additional causative missense mutation and for the p.G224T variant further splicing studies are necessary to determine its pathogenicity.