Christmas disease is due to deficiency of: September 2010
Ans. A: Deficiency of factor IX Haemophilia B (or hemophilia B) is a blood clotting disorder caused by a mutation of the Factor IX gene, leading to a deficiency of Factor IX. It is the less common form of haemophilia, rarer than haemophilia A. It is sometimes called Christmas disease after Stephen Christmas, the first patient described with this disease
Deficiency of factor IX
Deficiency of factor X
Deficiency of factor XI
Deficiency of factor XII