[Hypophosphatemia and rickets/osteomalacia].

It is important to know the pathophysiology of the inherited hypophosphatemic disorders for the research on the relationship between hypophosphatemia and rickets/osteomalacia. And the research on the pathogenesis of the X-linked hypophosphatemic vitamin D resistant rickets/osteomalacia has played central roles in this field. After the identification of PHEX gene for the responsible gene of the disorder, major interest of the research has shifted to the identification of phosphatonin, the natural substrate of PHEX and the novel phosphate-regulating hormone. Recent discovery of FGF23 for the responsible gene of oncogenic osteomalacia and autosomal dominant hypophosphatemic rickets may lead our knowledge on the phosphate regulation system to the new stage.