Allergic skin diseases, such as urticaria and atopic dermatitis, are highly related to the degranulation of mast cells and the balance between inflammatory and anti-inflammatory cytokines, such as interleukin- (IL-) 4, IL-6, IL-10, IL-13, interferon gamma (IFN-γ), and tumor necrosis factor alpha (TNF-α) [4, 5]. This evidence concerns the gene IFNG and urticaria.