Compared to the sham group, the intact FGF23 levels decreased at 4 weeks and were not significantly different at 16 weeks in the CKD group (Figure 4(c)); serum 1,25-(OH)2-D3 levels increased at 4 weeks and then decreased at 16 weeks in the CKD group (Figure 4(d)). The gene discussed is FGF23; the disease is chronic kidney disease.