In a mouse model of peanut allergy, we identified increased expression and activation of a novel gene, cytochrome P450, family 11, subfamily A, polypeptide 1 (CYP11A1), to be a central regulator of IL-13 production and an essential component in the development of peanut-induced intestinal anaphylaxis [8]. Here, IL13 is linked to peanut allergic reaction.