Since, (1) IL12 and other Th1 gene polymorphisms are associated with severe asthma [71, 72]; and (2) in the context of allergen-induced inflammation and AHR, IL12 reduces Th2 responses, including AHR [70], further analysis of roles for RGS2 in T-helper cell programming/function is appropriate. This evidence concerns the gene AHR and asthma.