The pathogenesis of AD remains unclear, but appears to be related to both genetic factors, such as a dysfunctional immune system where type 2 T helper cells secrete an excessive amount of interleukin-4 (IL-4) and interleukin-13 (IL-13), and environmental factors, such as house dust mites [5,6,7,8,9]. The gene discussed is IL13; the disease is Alzheimer disease.