Deep-Intronic Variant in RUNX2 Causing Pseudo-Exon Inclusion in a Family With Cleidocranial Dysplasia.

A deep-intronic single nucleotide variant in RUNX2 causes the characteristic clinical features of cleidocranial dysplasia (CCD) in a family via pseudo-exon inclusion into the mRNA. The pseudo-exon contains a premature stop codon and triggers mRNA decay, which results in RUNX2 haploinsufficiency, the known disease mechanism.