ALLELIC LOSS ON CHROMOSOME-17 IN HUMAN OVARIAN-CANCER

In order to identify a common region of deletion on chromosome 17 pote ntially containing a tumor-suppressor gene, 27 ovarian carcinomas and 3 ovarian tumors of low malignant potential (LMP) were examined for lo ss of heterozygosity (LOH) at 6 p arm and 10 q arm loci. Ninety percen t of all tumors had deletions at one or more loci. On the p arm, there was a single near-common region of deletion on 17p13.3 (D17S30/pYNZ22 . 1; 86% LOH), an intervening locus with a low LOH rate, and a more pr oximal locus on 17p 11.2 (D17S58/pEW301; 82% LOH) with a high LOH rate . In less aggressive tumors, LOH at D17S30 was not accompanied by LOH at p53. The q arm had a common region of deletion for high-stage carci noma at D17S579 (Mfd188; 74% LOH) on q21, a locus tightly linked to th e familial breast-ovarian-cancer syndrome (BRCAI) locus. D17S579 was l ost in all informative high-stage carcinomas and retained in all low-s tage carcinomas and tumors of LMP. There may be at least 2 tumor-suppr essor genes, an early-acting gene on the p arm and a gene on the q arm involved in tumor progression and metastasis.