The analysis of all 13 GLP1R exons and intron–exon junctions in 36 patients with poorly controlled T2DM on combination treatment with insulin and exenatide revealed an association of rs3765467 and rs761386 polymorphisms with clinical response defined as changes in the plasma glucose levels after 3 days of exenatide treatment. The gene discussed is INS; the disease is type 2 diabetes mellitus.