These results suggested that inactivation of the Phex gene in Hyp mice led to the increased expression of Dmp1 and Fam20c as well as that of Fgf23. The expression of both FGF23 and DMP1 was previously shown to increase in the bones of patients in the early stages of chronic kidney disease (CKD) [37]. This evidence concerns the gene PHEX and chronic kidney disease.