INS and type 1 diabetes mellitus: To test these hypotheses, we genotyped patients with T1D or T2D, as well as healthy controls, for two common SNPs in INS, rs689 and rs3842752, and two common SNPs in the α-subunit encoding portion of INSR, rs2245649, and rs2229429, and we examined if these SNPs associate with disease or the circulating levels of glycated hemoglobin (HbA1c), an indicator of glycaemic control, or with sIR levels.