Variations in the TCF7L2 gene have reduced insulin secretion from pancreatic β-cells and thus have an impaired response to incretins (dipeptidyl peptidase-4 inhibitors—DPP-4—and glucagon like peptide 1 receptor agonists—GLP1-RA), which have been shown to confer CV and renal protection in patients with diabetic kidney disease (Figure 1) [132]. The gene discussed is GLP1R; the disease is diabetic kidney disease.