Although circulating FGF23 undergoes cleavage in patients with normal kidney function and in those with mild CKD,[10] the majority of circulating FGF23 in dialysis patients is in its full-length form [11] and changes in circulating mineral ion and hormone concentrations may play a significant role in osteocytic protein expression as CKD advances. The gene discussed is FGF23; the disease is chronic kidney disease.