Factor VII deficiency: A cause of (or risk factor for) bleeding?

Among the rare bleeding disorders factor VII deficiency is the most common, but correlating deficiency with bleeding phenotype is challenging. In their study Lou and colleagues investigate a large cohort of unrelated factor VII deficient patients providing a further perspective on the link between genotype and phenotype in this disorder. Commentary on: Lou et al. Structural and functional characterization of novel F7 mutations identified in Chinese factor VII deficient patients. Br J Haematol. 2023;202:623–635.