As shown in Figures 5A,B, the expression of these two genes was effective at discriminating DKD from control samples, with AUCs of 0.945 (95% CI 0.891–0.988) for DUSP1 and 0.932 (95% CI 0.879–0.976) for PRKAR2B. To further evaluate the diagnostic efficacy of the two candidate biomarkers, the GSE47185 and GSE30122 datasets were merged as a validation set, which comprised 33 samples from patients with DKD and 67 samples from controls. This evidence concerns the gene PRKAR2B and diabetic kidney disease.