The serum neopterin levels exhibited a significant inverse correlation with eGFR (r = −0.359, P < 0.0001), and had positive associations with hsCRP (r = 0.285, P = 0.002), IL-6 (r = 0.212, P = 0.03), and IFN-γ (r = 0.32, P = 0.001) in the CKD subjects (Figure 2). This evidence concerns the gene IFNG and chronic kidney disease.