GLP1R and type 2 diabetes mellitus: Direct sequencing of the entire GLP1R coding region in 36 unrelated Japanese patients with T2DM identified five missense variants in exons: Pro7Leu (CCG → CTG, rs10305420, exon 1), Arg44His (CGC → CAC, rs2295006, exon 2), Arg131Gln (CGA → CAA, rs3765467, exon 4), Thr149Met (ACG → ATG, rs112198, exon 5), and Leu260Phe (TTA → TTC, rs1042044, exon 7).