Who is at risk for developing a brain tumor? Exposure to some agents, such as vinyl chloride or radiation, may increase the risk. A family history of glioma can also be a risk factor, accounting for approximately 2% of glioma patients (1). However, the known causes of glioma represent only a small percentage of patients, with most cases arising “spontaneously.” Could a more subtle genetic predi...

We have been quantitating, as a marker of cancer susceptibility, induced chromatid breaks in lymphocyte cultures exposed to chemical mutagens. This report highlights the consistency of the results from two case-control studies, using different methods of presenting the data. In both the lung cancer case-control study, which used bleomycin, a radiomimetic agent, as the test mutagen, and the mela...

Lymphocytes from 15 untreated patients with non-Hodgkin lymphoma (NHL) and 15 controls were exposed to 0.08 micrograms/ml mitomycin C, and the frequency and distribution of structural chromosome aberrations (chromatid and chromosome gaps, breaks, and exchanges) were analyzed in 100 mitoses per subject. The mean frequencies of aberrant cells, and gap, break, and gap + break events were 8.7, 0.9,...

The structural maintenance of chromosomes (SMC) family of proteins has been implicated in the repair of DNA double-strand breaks (DSBs) by homologous recombination (HR). The SMC1/3 cohesin complex is thought to promote HR by maintaining the close proximity of sister chromatids at DSBs. The SMC5/6 complex is also required for DNA repair, but the mechanism by which it accomplishes this is unclear...

The meiotic properties of paracentric inversion heterozygotes have been well studied in insects and plants, but not in mammalian species. In essence, a single meiotic recombination event within the inverted region results in the formation of a dicentric chromatid, which usually breaks or is stretched between the two daughter nuclei during the first meiotic anaphase. Here, we provide evidence th...

Intercalator-induced DNA strand breaks in mammalian cells represent topoisomerase II:DNA complexes trapped by intercalators. These complexes are detected as protein-associated DNA single-strand breaks (SSB) and DNA double-strand breaks (DSB) by filter elution. Using Chinese hamster lung fibroblasts (V79 cells) that were treated for 30 min with various concentrations of 4'-(9-acridinylamino)meth...

A technique has been perfected for enabling good microscope preparations to be obtained from the larval ganglia of Drosophila melanogaster. This system was then tested with X-rays and an extensive series of data was obtained on the chromosome aberrations induced in the various stages of the cell cycle.-The analysis of the results obtained offers the following points of interest: (1) There exist...

The cohesin complex is required for the cohesion of sister chromatids and for correct segregation during mitosis and meiosis. Crossover recombination, together with cohesion, is essential for the disjunction of homologous chromosomes during the first meiotic division. Cohesin has been implicated in facilitating recombinational repair of DNA lesions via the sister chromatid. Here, we made use of...

Background: Although eliminated rapidly from the body due to low solubility in blood and tissues, anesthetic gases have been reported to be neurotoxic, teratogenic and carcinogenic. Genetic material has been shown to be a sensitive target of numerous harmful agents. Aim of the Work: To evaluate genotoxic risk of occupational exposure to anesthetic gases in a group of operating room nurses. Subj...