The disease in which a single protein that is a part of the cascade of proteins involved in blood clotting is affected is

Haemophilia is the disease in which blood clotting is affected since a single protein that is a part of the cascade of proteins involved in blood clotting is affected.
There are three types of haemophilia:

• Haemophilia A (classical haemophilia) is the most common type of haemophilia and is caused by a deficiency in a protein called clotting factor VIII. 
• Haemophilia B (Christmas disease) is caused by a deficiency in a protein called clotting factor IX.
• Haemophilia C is a rarer form of haemophilia that is caused by a deficiency in a protein called clotting factor XI.