IL13 and asthma: It is also noteworthy that patients with the common polymorphism have depressed levels of IFNγ and IL-13, the former demonstrating a lack of TH1-like disease (where high IFNγ and low IL-13 are expected), and the latter arguing against TH2-like disease, such as asthma (where high IL-4 and IL-13 are expected).