A case of a Taiwanese patient with cleidocranial dysplasia possessing a de novo mutation of RUNX2 gene

Cleidocranial dysplasia (CCD, #119600) is a rare, autosomal dominant bone disease characterized by hypoplastic or aplastic clavicles, wide cranial sutures, supernumerary teeth, short stature, and other skeletal disorders. This disease gene has been mapped to chromosome 6p21 within a region containing CBFA1, a member of the runt family of transcription factors (RUNX2). We report one Taiwanese girl with CCD, with multiple wormian bones, persistent synchondrosis, supernumerary teeth, hypoplasia of clavicles, delayed ossification of pubic bone, and short stature. She also has partial fusion of the left 4th and 5th ribs, and posterior cerebral artery malformation. We performed sequence analysis of the RUNX2 gene, and detected a heterozygous C to G transition mutation at nucleotide 1115 in exon 7, leading to P372R mutation. This is an unreported missense mutation in exon 7 which effected the trausactivation domain of RUNX2.