In a multicenter study, a significant genetic overlap between adult and pediatric patients with PPI-REE and those with EoE was observed, including genes for eosinophil chemotaxis (CCL26), barrier molecules (desmoglein DSG1), tissue remodeling (POSTN), and mast cells (CPA3) (33). This evidence concerns the gene CCL26 and eosinophilic esophagitis.