MOLECULAR ANALYSIS OF 2 PUTATIVE TUMOR-SUPPRESSOR GENES, PTEN AND DMBT, WHICH HAVE BEEN IMPLICATED IN GLIOBLASTOMA-MULTIFORME DISEASE PROGRESSION

The transition from low grade astrocytoma to glioblastoma multiforme i s almost always accompanied by the loss of genetic markers from chromo some 10. Recently two genes, PTEN/MMAC1/TEP1 and DMBT, have been isola ted from chromosome 10q. We have analysed these two genes for mutation s in 21 primary glioblastomas, An exon by exon screen of the PTEN gene using SSCP failed to identify any mutations in this tumour series, In contrast, 38% of tumours showed intragenic homozygous deletions in th e DMBT gene, The fact that the majority of gliomas do not carry mutati ons in either of these genes suggests that there may still be other ge nes on chromosome 10 which are important in the development of gliobla stoma multiforme.