1,25(OH)2D levels were also increased in CKD mice: Fgfr1–3flox/flox, control (27.7 ± 8.5 pg/mL, n = 5) vs CKD (209.3 ± 63.8 pg/mL, n = 5), P < 0.001; αKlothoflox/flox, control (48.0 ± 15.8 pg/mL,n = 4) vs CKD (122.2 ± 37.7 pg/mL, n = 5), P < 0.01; Fgfr1–4flox/flox, control (45.0 ± 9.5 pg/mL, n = 5) vs CKD (88.9 ± 24.0 pg/mL, n = 4), P < 0.01. This evidence concerns the gene FGFR1 and chronic kidney disease.