The discovery of the metalloprotease referred to as ADAMTS13 (A Disintegrin-like And Metalloprotease with ThromboSpondin type 1 motif 13), as many other examples in biomedical research, found its way in the attempt to address the issue concerning the pathogenesis of severe forms of thrombotic microangiopathies (TMAs). This evidence concerns the gene ADAMTS13 and thrombotic microangiopathy.