In 1817, James Parkinson's initial essay described a neurological disease that was later named after its discoverer and is now referred to as Parkinson's disease. Reye's syndrome was named after the Australian doctor who first described the disorder. Dr. Down's name was used to distinguish the syndrome for which he was famous, Cushing's syndrome was named after Dr. Cushing and Alzheimer's disease after its discoverer.

The oldest blood diseases are referred to as hemophilia, and Hemophilia B, which is also known as Christmas Disease, is incurable, affecting approximately 2,800 Americans. The name "Christmas Disease," in contrast to many medical diseases, comes from the surname of the family in which the disease was first studied and identified as a hereditary disorder in 1952.

One of the earliest researchers of the disease, Dr. R.G. Macfarlane used the patient's surname, Christmas, to refer to the disease and also to refer to the clotting factor, called the "Christmas Factor" (Factor IX), which is part of a complicated blood-clotting cascade.  Most people, who have normal blood-clotting activity, possess the Christmas Factor.

And thus, the spirit of Christmas lives on!

NOTE:

In hemophilia B, gene mutations now can be defined in nearly all patients. Carrier and prenatal diagnosis can be performed by mutation tracing, if a blood sample can be obtained from a hemophilic relative. If no such relative is available, blood chemistry analysis may be feasible, depending on the family tree.