<；P>；PROBLEM TO BE SOLVED: To provide a FGF (fibroblast growth factor) 23 protein variant or its partial fragment or new applications of DNA encoding those. <；P>；SOLUTION: The present inventors examined whether or not FGF 23 protein and its variant give an influence on progress of chronic renal insufficiency. Particularly, the inventors administered an expression vector comprising DNA encoding a wild type FGF23 protein and an expression vector comprising DNA encoding a R179Q FGF23 protein variant to a chronic renal insufficiency rat, and then, carried out studies on biochemical parameters and histologic study. As a result, it is found out that progress of the renal insufficiency is inhibited by administering the expression vector comprising the DNA encoding the R179Q FGF23 protein variant. <；P>；COPYRIGHT: (C)2004,JPO
