Factor XII (also called Hageman factor) was first discovered in 1955 when a routine blood sample of a man named John Hageman had prolonged clotting time in test tubes. Hageman was then examined by hematologist Oscar Ratnoff, who found that Hageman lacked a previously unidentified clotting factor, even though he had no hemorrhagic symptoms.
Date
Date Format
YYYY
Decade
1950s
Notable Historic Moment
No
Timeline