IL-13 is a critical cytokine in the pathoetiology of EoE (Blanchard et al. 2011; O’Shea et al. 2018; Davis et al. 2016; D’Mello et al. 2016; Cianferoni and Spergel 2016; Rothenberg et al. 2015; Sherrill et al. 2014b; Sherrill et al. 2014a; Zuo et al. 2010; Blanchard et al. 2007; Mishra and Rothenberg 2003). The gene discussed is IL13; the disease is eosinophilic esophagitis.