A putative Fgf23 bone enhancer, located ~38 kb upstream, was targeted with sgRNAs (targeting TGGAAGCAAGGGATTTACAG and GAGGCTGACACAGCATGCCT) using CRISPR/Cas9 technology, resulting in a 1071 bp deletion. The deleted sequence contains putative CTCF-binding site Rr133120. (J:281531)