title: Loss of heterozygosity studies in tumors from families with breast-ovarian cancer syndrome.
abstract: A gene (BRCA1) predisposing for familial breast and ovarian cancer has been mapped to chromosome band 17q12-21. Based on the observation that ovarian tumors from families with breast and ovarian cancer lose the wild-type allele in the region for the BRCA1 locus, it has been suggested that the gene functions as a tumor suppressor gene. We have studied chromosomal deletions in the BRCA1 region in seven breast tumors, three ovarian tumors, one bladder cancer, and one colon cancer from patients in six families with breast-ovarian cancer, in order to test the hypothesis of the tumor suppressor mechanism at this locus. We have found a low frequency of loss of heterozygosity at this region, and our results do not support the idea that BRCA1 is a tumor suppressor gene. Alternatively, the disease segregating in these families is linked to one or more different loci.
authors.affiliation: National Institute of Oncology and Radiobiology, Havana City, Cuba.
authors.forename: M
authors.initials: M
authors.lastname: Zelada-Hedman
authors.forename: M
authors.initials: M
authors.lastname: Torroella
authors.forename: R
authors.initials: R
authors.lastname: Mesquita
authors.forename: M
authors.initials: M
authors.lastname: Nordenskjöld
authors.forename: L
authors.initials: L
authors.lastname: Skoog
authors.forename: A
authors.initials: A
authors.lastname: Lindblom
mesh_terms: D001943:Breast Neoplasms / Q000235:genetics*; D002872:Chromosome Deletion; D002874:Chromosome Mapping; D002886:Chromosomes, Human, Pair 17; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D016147:Genes, Tumor Suppressor / Q000235:genetics; D008040:Genetic Linkage; D006579:Heterozygote; D006801:Humans; D009386:Neoplastic Syndromes, Hereditary / Q000235:genetics*; D010051:Ovarian Neoplasms / Q000235:genetics*; D010375:Pedigree; D016133:Polymerase Chain Reaction