Congenital Thrombotic Thrombocytopenic Purpura (cTTP) is a severe autosomal recessive disorder due to ADAMTS13 (a disintegrin-like and metalloprotease with thrombospondin type 1 motif, 13) rare variants and is characterized by uncleaved ultra-large vWF and thrombotic microangiopathy, frequently triggered by infections. The gene discussed is ADAMTS13; the disease is thrombotic thrombocytopenic purpura.