PTEN and eosinophilic esophagitis: The PTEN gene has been implicated in the pathogenesis of different eosinophilic gastroenteropathies, including eosinophilic esophagitis [17], and in the regulation of chemotactic responses of leukocytes through its effect on the Rho GTPase/Rac pathway, which is fundamental for the chemotaxis and activation response of eosinophils [18].