Zorena et al. in a cross-sectional study including 126 patients found that in children with type 1 DM and retinopathy the serum concentration of TNF-α was significantly higher and the concentration of IL-12 was significantly lower than in the group without retinopathy suggesting that increased TNF-α production may be the result of insufficient IL-12 concentrations (81). This evidence concerns the gene TNF and retinal disorder.