why hemophilia b is called christmas disease

The condition is called Christmas disease because of its discovery in 1952 by two British doctors, Sir Christmas P. Norman and Dr. Brinkhous. They were conducting research on a rare blood clotting disorder and discovered that the gene that caused it was located on the X chromosome. They named the disorder Christmas disease in honor of Sir Christmas, who had died only a few years earlier. Since then, the disorder has also been called hemophilia B, due to the similarity of symptoms between the two conditions.