A 6-month-old infant was admitted with new-onset hemolytic uremic syndrome (HUS), characterized by hemolytic anemia (hemoglobin: 6.5 g/dL), thrombocytopenia (PLT/mm3), and laboratory evidence of hemolysis (LDH 2000 U/L, undetectable haptoglobin and the presence of schistocytes on peripheral blood smear). The gene discussed is HP; the disease is hemolytic-uremic syndrome.