In Yixing population, a linear increase in insulin was observed with the variants of rs12929077 (P = 0.013) in untreated T2D cases, and the insulin concentration in the subjects with AA, AG and GG genotypes was 8.70 ± 8.05, 10.71 ± 11.16 and 13.41 ± 14.26 mU/L, respectively. Here, INS is linked to type 2 diabetes mellitus.