Hemophilia is an inherited disorder of the blood in which essential clotting factors are either partly or completely missing. The term "hemophiliac" was probably first coined in 1828 by a pupil of the German physician Johann Schönlein (1793-1864) to describe the condition in which patients are predisposed to hemorrhage or bleeding. There are very early historical references to a disorder like hemophilia, including an apparent reference in the Jewish Talmud from the second century and a description by the Islamic surgeon Abu al-Qasim in the tenth century. More recently, hemophilia has influenced the fates of the royal families of Europe because a recessive mutation apparently occurred in the X-chromosome of the English Queen, Victoria, (1819-1901), and spread through intermarriage to the Russian and Spanish royal families. One out of Queen Victoria's four sons suffered from hemophilia and two out of her five daughters were carriers. At that...