A common origin of the 4143insA ADAMTS13 mutation
Severely deficient activity of the von Willebrand Factor (VWF) cleaving metalloprotease,ADAMTS 13, is associated with thrombotic thrombocytopenic purpura (TTP). The mutation spectrum ofADAMTS 13 is rather heterogeneous, and numerous mutations spread across the gene have been described in association with congenital TTP. The 4143insA mutation is unusual with respect to its geographic concentration.