In fact, insulin concentrations decreased with age at T2D diagnosis (r = − 0.111; p < 0.0001), which was much greater in males (r = − 0.189; p < 0.0001) than in females (r = − 0.051; p > 0.05) and independent of allele type, suggesting the effect was likely related to age. Here, INS is linked to type 2 diabetes mellitus.