The first large-scale study examining the relationship between GLP-1 RAs and the incidence of gastroesophageal reflux disease (GERD) and its complications, involving 127 million adult patients with T2DM, revealed an increased risk of first-time erosive esophagitis, Barrett’s esophagus, and non-erosive reflux disease, regardless of the GLP-1 RA type used. The gene discussed is GLP1R; the disease is type 2 diabetes mellitus.