Serum SOD activity was significantly decreased in T1DM (0,75 ± 0,18 U; 95% CI: 0,72, 0,79) and in T2DM patients (0,71 ± 0,33; 95% CI: 0,67, 0,74) compared to the control subjects (1,67 ± 0,33, 95% CI: 1,61, 1,72), both p < 0,01. The gene discussed is SOD1; the disease is type 2 diabetes mellitus.