Interleukin-13

Few genes appear to be as critical for the pathogenesis of allergic inflammation in humans and animal models as interleukin (IL)-13, and even fewer appear to determine susceptibility to allergy and Asthma across human populations as consistently as IL-13. The reason behind the central role of this cytokine in disease pathogenesis probably lies in the properties of IL-13, the frequency with which the human IL-13 locus is targeted by natural genetic variation, and the functional consequences of this variation. Here we will discuss the properties of IL-13 relevant to allergic lung inflammation; we will review the results of genetic association studies investigating the relationship between IL-13 polymorphisms and allergic phenotypes; and we will propose a blueprint for functional studies of genetic variation based on the experience gained through the analysis of a common IL-13 coding variant.