Atopic and allergic conditions, including atopic dermatitis, food allergies, atopic asthma, and allergic rhinitis, are all mediated by a Th2-type immune reaction, which involves the IgE antibody response, IL-4 and IL-5 cytokines, and tissue infiltration with eosinophils and mast cells [130]. This evidence concerns the gene IL4 and atopic eczema.