It protects esophageal epithelia from hydrogen peroxide-induced oxidative stress. It suppresses acidic bile acid-induced reactive oxigen species (ROS) and protects against oxidative DNA damage and double-strand breaks. 2 glutathione + H2O2 = glutathione disulfide + 2 H2O Expressed in esophageal epithelial cells; expression is up-regulated after exposure to acidic bile acids. The disease is caused by variants affecting the gene represented in this entry. The pathologic mechanisms leading to Barrett esophagus involve GPX7 dysfunction that results in higher levels of hydrogen peroxide and ROS-induced oxidative stress and DNA damage in esophageal cells. Belongs to the glutathione peroxidase family. Wrong choice of frame.