Mutation screening of EXT1 and EXT2 by denaturing high-performance liquid chromatography, direct sequencing analysis, fluorescence in situ hybridization, and a new multiplex ligation-dependent probe amplification probe set in patients with multiple osteochondromas.
Multiple osteochondromas (MO) is an autosomal-dominant skeletal disorder characterized by the formation of multiple cartilage-capped protuberances. MO is genetically heterogeneous and is associated with mutations in the EXT1 and EXT2 genes. In this study we describe extensive mutation screening in a set of 63 patients with clinical and radiographical diagnosis of MO. Denaturing high-performance liquid chromatography analysis revealed mutations in 43 patients. Additional deletion analysis by fluorescence in situ hybridization and a newly developed multiplex ligation-dependent probe amplification probe set identified one patient with an intragenic EXT1 translocation, three patients with a partial EXT1 deletion, and one patient with a partial EXT2 deletion. Thirty-six patients harbored an EXT1 mutation (57%), and 12 had an EXT2 mutation (19%). We show that our optimized denaturing high-performance liquid chromatography/sequencing/multiplex ligation-dependent probe amplification protocol represents a reliable and highly sensitive diagnostic strategy for mutation screening in MO patients. Clinical analysis showed no clear genotype-phenotype correlation in our cohort of MO patients.
Jennes
Ivy
I
Department of Medical Genetics, University and University Hospital of Antwerp, Antwerp, Belgium.
Entius
Mark M
MM
Van Hul
Els
E
Parra
Alessandro
A
Sangiorgi
Luca
L
Wuyts
Wim
W
D002851:Chromatography, High Pressure Liquid; D004252:DNA Mutational Analysis; D015342:DNA Probes; D004273:DNA, Neoplasm / Q000235:genetics; D005097:Exostoses, Multiple Hereditary / Q000175:diagnosis* / Q000235:genetics*; D005820:Genetic Testing; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D009154:Mutation / Q000235:genetics*; D017351:N-Acetylglucosaminyltransferases / Q000235:genetics*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods*; D009691:Nucleic Acid Denaturation; D015203:Reproducibility of Results; D017422:Sequence Analysis, DNA; D000099065:Exostosin 2; D000099058:Exostosin 1
D015342:DNA Probes; D004273:DNA, Neoplasm; D017351:N-Acetylglucosaminyltransferases; D000099058:Exostosin 1; D000099065:Exostosin 2