Interleukin-13(IL-13) is a cytokine producedby Th2 cells, a subsetof T helper cells, and plays crucial roles in the immune system.1,2 It stimulates B-cell proliferation and differentiation, enhancesIgE antibody production, and contributes to various allergic diseases,such as allergic rhinitis and atopic dermatitis.3,4Figure 1 shows a schematicdiagram illustrating the symptoms and pathological consequences causedby the overinduction of IL-13. This evidence concerns the gene IL13 and allergic rhinitis.