In this study, patients with chronic renal insufficiency (CKD1-5, defined by glomerular filtration rate，GFR) and healthy people as control will be recruited (50/group, total 300). Blood urea nitrogen, creatinine,lumbar and hip bone mineral density, bone turnover biochemical markers including serum total propeptide of type I procollagen（PINP）, bone alkaline phosphatase（BALP）, bone Gla-protein (BGP) and β-CrOSSlaps（β-CTX）, serum calcium and phosphorus and related regulators including fibroblast growth factor 23 (FGF23), 25-hydroxyl-Vitamin D （25-OH-VitD）, parathyroid hormone（PTH） will be detected. The relationship between kidney function and bone turnover, and the rules throughout the development process of renal osteodystrophy will be analysed.The micro ribonucleotide（miRNA）array will also be performed to screen the biomarkers of renal osteodystrophy in different stage.
