DETAILED PHYSICAL AND DELETION MAPPING OF 8P WITH ISOLATION OF YAC CLONES FROM TUMOR-SUPPRESSOR LOCI INVOLVED IN COLORECTAL-CANCER

Loss of heterozygosity (LOH) of markers at chromosome 8p is frequently noted in many different tumour types, including colorectal cancer, Nu merous investigations indicate the presence of more than one tumour su ppressor gene (TSG) located on 8p. In this study, we describe a detail ed LOH map in colorectal cancer and relate this to physical mapping da ta from reduced radiation 8p hybrids, yeast artificial chromosome (YAC ) co-localisation of markers and fluorescence in situ hybridisation da ta,;These data indicate the presence of two regions harbouring putativ e TSG's between the polymorphic markers for the LPL gene-D8S298 (simil ar to 4 Mb) and the markers D8S136-D8S137 (similar to 8 Mb), Yeast Art ificial Chromosomes (YAC) have been isolated from these regions of int erest to aid the localisation of the putative TSG's.