Prolongation of both PT and APTT, and a normal TT in our patient were suggestive of coagulation factor deficiency in the common pathway (factors II, V, VII, and X), along with factor IX deficiency or presence of inhibitors of prothrombin, fibrinogen, factor V, or factor X. Full correction of the abnormal APTT and PT by pooled normal plasma ruled out factor inhibitors and suggested a deficiency of coagulation factors. The gene discussed is F2; the disease is complement factor I deficiency.