The supposed mechanisms responsible for this increase of GERD after SG would be an alteration of the angle of His due to surgery itself; hypotony of the lower esophageal sphincter after division of muscular sling fibers; decrease of gastric volume and consequent increased intragastric pressure; worsening of hiatal hernia; probable decrease of ghrelin, hence dysmotility and neofundus formation [12]. This evidence concerns the gene GHRL and gastroesophageal reflux disease.