Higher serum TGFβ1 levels were revealed in T2DM and RF groups compared to the HC subjects, but serum TGFβ1 had a significant positive correlation with BMI (body mass index) (r = 0.564; p = 0.0002), waist circumference (r = 0.432; p = 0.008) and a negative correlation with eGFR (r = −0.471; p = 0.008) only in the T2DM group. This evidence concerns the gene TGFB1 and type 2 diabetes mellitus.