The optical density (divided by GAPDH) of Collagen I was higher in DM group than the control group (0.504 ± 0.161 vs. 0.297 ± 0.040, P < 0.001), while there was no difference of Collagen III (0.284 ± 0.109 vs. 0.293 ± 0.101, P = 0.685). This evidence concerns the gene GAPDH and diabetes mellitus.