In conclusion, this study has described that SCD patients with or without ON presented significantly reduced TCD4+, TCD8+, and TCD4+ naïve cell frequencies in PB-MNC and increased frequency of circulating CD4+T cells able to simultaneously produce IFN-γ+/IL4+ and IL-17+/IL4+ compared to healthy controls. This evidence concerns the gene IFNG and Schnyder corneal dystrophy.