Deletions of the RUNX2 gene are present in about 10% of individuals with cleidocranial dysplasia.
Cleidocranial Dysplasia (CCD) is an autosomal dominant skeletal disorder characterized by hypoplastic or absent clavicles, increased head circumference, large fontanels, dental anomalies, and short stature. Hand malformations are also common. Mutations in RUNX2 cause CCD, but are not identified in all CCD patients. In this study we screened 135 unrelated patients with the clinical diagnosis of CCD for RUNX2 mutations by sequencing analysis and demonstrated 82 mutations 48 of which were novel. By quantitative PCR we screened the remaining 53 unrelated patients for copy number variations in the RUNX2 gene. Heterozygous deletions of different size were identified in 13 patients, and a duplication of the exons 1 to 4 of the RUNX2 gene in one patient. Thus, heterozygous deletions or duplications affecting the RUNX2 gene may be present in about 10% of all patients with a clinical diagnosis of CCD which corresponds to 26% of individuals with normal results on sequencing analysis. We therefore suggest that screening for intragenic deletions and duplications by qPCR or MLPA should be considered for patients with CCD phenotype in whom DNA sequencing does not reveal a causative RUNX2 mutation.
Ott
Claus E
CE
Institut für Medizinische Genetik, Charité-Universitätsmedizin Berlin, 13353 Berlin, Germany. claus-eric.ott@charite.de
Leschik
Gundula
G
Trotier
Fabienne
F
Brueton
Louise
L
Brunner
Han G
HG
Brussel
Wim
W
Guillen-Navarro
Encarna
E
Haase
Claudia
C
Kohlhase
Juergen
J
Kotzot
Dieter
D
Lane
Andrew
A
Lee-Kirsch
Min Ae
MA
Morlot
Susanne
S
Simon
Marleen E H
ME
Steichen-Gersdorf
Elisabeth
E
Tegay
David H
DH
Peters
Hartmut
H
Mundlos
Stefan
S
Klopocki
Eva
E
D002973:Cleidocranial Dysplasia / Q000235:genetics*; D004252:DNA Mutational Analysis; D017353:Gene Deletion; D006579:Heterozygote; D006801:Humans; D016133:Polymerase Chain Reaction