In a study of 80 children with ALL, Battisti et al. found that the plasma levels of reactive TBARS and the serum levels of protein carbonyls were significantly higher in patients than in controls, and was accompanied by alterations in enzymatic antioxidant defenses, where SOD and CAT antioxidant activities were significantly reduced at diagnosis moment [3]. The gene discussed is CAT; the disease is acute lymphoblastic leukemia.