Klotho Gene Polymorphism in Dialyzed Patients With Hyperphosphatemia

Patients with chronic kidney disease (CKD) and those with end-stage renal disease (ESRD) undergoing renal replacement therapies show elevated serum phosphate levels which predispose them to cardiovascular calcifications and high risks of death from cardiovascular diseases. However, in certain patients hyperphosphatemia is not related to dialysis insufficiency, excessive daily dietary phosphorus intake or high serum parathyroid hormone (PTH) levels, suggesting that other mechanisms could be involved. Transgenic mice lacking the klotho gene showed a phenotype which resembles that of dialyzed ESRD patients, in the sense that they have hyperphosphatemia, vascular calcifications, and a short lifespan. This study will analyze whether functional polymorphisms or variants in the human klotho gene are associated with hyperphosphatemia in these patients.