Of the 42 candidate proteins expressing genes, 16 (ANG, CD27, CDH3, CKAP4, COL6A3, GFRA1, HAVCR1, IGFBP4, IGFBP6, LTBR, NEFL, TINAGL1, TNFRSF21, TNFRSF4, VSIG4, WFDC2) genes were significantly correlated with CKD and kidney fibrosis in general populations (Supplementary Table S4 (16)) (21). The gene discussed is IGFBP4; the disease is chronic kidney disease.