Isolation and characterization of glioblastoma-associated homozygously deleted DNA fragments from chromosomal region 9p21 suggests involvement of multiple tumour suppressor genes

Representational difference: analysis (RDA) of a human glioblastoma xenogra ft resulted in the isolation of five tumour-associated homozygously deleted DNA fragments, all originating from chromosome 9, region p21. Subsequent a nalysis of a series of ten glioblastomas using the newly isolated RDA fragm ents in conjunction with a series of known 9p21 DNA markers revealed homozy gous deletions in nine of the ten (90 per cent) tumors. These deletions enc ompass the p15lp16 complex and two additional putative tumour suppressor lo ci. The RDA fragments correspond to the latter two loci. Taken together, th ese results suggest the involvement of multiple tumour suppressor genes fro m the 9p21 region in glioblastoma tumorigenesis, The novel RDA fragments wi ll he instrumental in the isolation of the relevant genes. Copyright (C) 19 99 John Wiley & Sons, Ltd.