GLP-1 is similar to but unlike GIP, actions of GLP-1 are better preserved in type 2 diabetes mellitus (T2DM) patients, which makes it a highly desirable target for drug discovery for T2DM (Sharma and Bhatia, 2020); (Nauck et al., 1993). The gene discussed is GLP1R; the disease is type 2 diabetes mellitus.