Hypophosphatemia together with decreased concentration of FGF23 leads to the stimulation of 1α-hydroxylase (CYP27B1) and inhibition of CYP24A1, that results in an increment of 1,25(OH)2D3 levels, leading to hypercalcemia and hypercalciuria. The gene discussed is CYP24A1; the disease is Hypercalciuria.