DETAILED DELETION ANALYSIS OF SPORADIC BREAST-TUMORS DEFINES AN INTERSTITIAL REGION OF ALLELIC LOSS ON 17Q25

Whole genome analyses of breast tumors with polymorphic markers have d etected nonrandom loss of heterozygosity on multiple chromosomes, prov iding clues to the locations of suspected tumor suppressor genes. Tumo rs are thought to initiate, progress, and metastasize as mutations acc umulate in multiple growth-regulatory genes; thus, identification and characterization of these genes are critical to understanding and cont rolling breast tumorigenesis. To map more precisely a novel breast tum or suppressor gene that has been localized previously to distal 17q, w e constructed a detailed deletion map of 17q25 by analyzing eight micr osatellite markers on 39 sporadic primary breast tumors. The smallest overlapping region of interstitial loss was narrowed to approximately 3 cM and included D17S937/AFM 107ye3, which showed the highest percent age of allelic loss (41%). These results provide a framework from whic h a genomic contig will be constructed and candidate transcripts will be analyzed. (C) 1996 Wiley-Liss, Inc.