MAPPING A PUTATIVE TUMOR-SUPPRESSOR GENE ON CHROMOSOME-9 BANDS P21-P22 WITH MICRODISSECTION PROBES

Deletions of the short arm of chromosome 9 have been observed in a num ber of malignant cell lines and primary tumor samples using cytogeneti c and molecular techniques. These tumors include acute lymphoblastic l eukemias, lymphomas, gliomas, melanomas, mesotheliomas, bladder cancer , and lung cancer. The smallest region of overlap (SRO) of these delet ions is thought to contain a tumor suppressor gene. A microdissection library was constructed from bands 9p21-p23 to obtain DNA probes that would be useful in further defining the limits of the deletions. Eight single-copy probes were found to be homozygously deleted in at least 1 of the 10 cell lines examined. The mapping of these 8 clones using a panel of cell lines with deletions revealed that 3 probes mapped telo meric to the SRO and 5 clones mapped centromeric to the SRO. (C) 1999 Academic Press, Inc.