OBJECTIVETo develop a new denaturing high performance liquid chromatograph (DHPLC)-based method to screen patients with EXT gene mutation and to study the gene mutation in three families with multiple exostoses.

METHODSAll the exons of EXT gene, including the intro-exon boundaries, were amplified by PCR. Linkage analysis and DHPLC screening were carried out to identify the mutations. DNA sequencing was used to confirm the mutations.

RESULTSTwo known splice site mutations, IVS2+1 G to A and IVS7+1 G to T, and two SNPs have been detected in EXT2 or EXT1 gene.

CONCLUSIONThe transversions of IVS2+1 G to A and IVS7+1 G to T in EXT2 gene are suggested to be the disease-causing mutations and the DHPLC is a high throughout, sensitive, simple, quick, economical method to screen gene mutation in hereditary multiple exostosis.