New enhancers from the SOX9 region with PRS-associated single nucleotide variants.

<p><b>(A) p300-PK17</b>, spatiotemporally altered expression: F1 dual-fluorescence reporter transgenic embryos shown at 48, 72 and 96 hpf. At 48 and 72 hpf the Wt(G) allele drives expression in the region around the oral cavity (OC) (white arrowhead). At 96 hpf Wt(G) drives expression in the palatoquadrate (PQ) (curved white arrow) and Meckel’s cartilage (MC) (open arrow). The Mut(A) allele is able to drive OC expression at 48 hpf, but this is lost by 72 hpf and at 96 hpf no PQ and MC expression is observed. <b>(B) hoc-CNE-D</b>, tissue-specific CRE with unaltered expression: F1 dual-fluorescence transgenic embryos at 72 and 96 hpf. The Wt(T) and the Mut(C) alleles both drive expression in olfactory placode (OP), brain (BR), and ceratobranchials (CB). <b>(C) p300-PK22</b>, craniofacial CRE with unaltered expression: F1 dual-fluorescence transgenic embryos at 72 hpf. The Wt(A) and Mut(C) allele both drive expression in the region around the oral cavity (OC). <b>(D-E)</b> RNA <i>in situ</i> hybridisation analysis of zebrafish <i>sox9a</i> and <i>sox9b</i> at 72hpf and 96hpf, showing overlap of reporter gene expression driven by the p300-Pk17, hoc-CNE-D and p300-Pk22 elements with the endogenous <i>sox9a</i> and <i>sox9b</i> expression pattern in the developing jaw. Wt: wild-type; Mut: mutant; hpf: hours post fertilization.