"[TTP] was known as a dangerous disorder, in which patients suddenly became very ill and could be treated only by replacing their blood plasma" said HHMI investigator David Ginsburg.

On October 4, 2001 researchers have determined the cause of a potentially deadly inherited blood-clotting disorder that can lead to kidney failure or stroke. The researchers found that the disorder, thrombotic thrombocytopenic purpura (TTP), is caused by mutations in a gene that render the ADAMTS13 enzyme ineffective. The research suggests that it might be possible to treat TTP by administering an active form of the enzyme, in much the same way that people with hemophilia receive clotting factor.