For peanut specifically, there has been recent development in component testing for diagnosis. This includes serum-specific IgE for various peanut proteins such as Ara h 1, 2, 3, and 8. The clinical utility of component testing remains yet to be fully determined, but testing to these proteins in patients allergic to peanut has been shown to be more specific and may correlate with various clinical phenotypes. For example, IgE to Ara h 2 was shown to be more specific than testing to whole peanut IgE when confirmed by OFC.32 IgE to storage proteins, Ara h 1, 2, and 3, has been associated with severe allergic reactions,33 whereas Ara h 8 seems to correlate with milder, oral-allergy symptoms, likely due to structural similarities to the major allergen in birch pollen.34