Those changes that have been well-described, by ourselves and others, include eosinophilia, elevated serum IgE, a Th2-dominant cytokine profile (increased IL-4, IL-5, and IL-10, decreased IL-2 and IFNγ [4, , , –8], decreased levels of CD4+ lymphocytes and a decreased CD4 to CD8 ratio, increased immune activation and apoptosis [4, 9, 10], impaired immune response to recall antigens [11, 12], impaired signal transduction, and anergy [13, 14]. The gene discussed is IGHE; the disease is Increased total eosinophil count.