The total number of activated C3 fragments, including intact C3 (195 kDa), C3bα' (110 kDa), C3α (120 kDa), C3β (75 kDa), α-1 fragment of iC3b (65 kDa), and C3cα' fragment-2, (43 kDa) were analyzed in the PDR and no-DM controls. The gene discussed is C3; the disease is diabetes mellitus.