RT Book, Section A1 Klapacz, Joanna A1 Gollapudi, B. Bhaskar A2 Klaassen, Curtis D. SR Print(0) ID 1158498022 T1 Genetic Toxicology T2 Casarett & Doull’s Toxicology: The Basic Science of Poisons, 9th edition YR 2019 FD 2019 PB McGraw-Hill Education PP New York, NY SN 9781259863745 LK accesspharmacy.mhmedical.com/content.aspx?aid=1158498022 RD 2024/04/19 AB Genetic toxicology is the study of genetic damage to the hereditary material that results in genetic alterations. Included in this broad definition are chemical and physical agents that cause mutagenicity, or transmissible genetic alterations, and genotoxicity. In contrast to mutagenicity, genotoxicity covers a broader spectrum of endpoints, including DNA damage such as DNA strand breaks and DNA adduct biomarkers (both pro-mutagenic and non-mutagenic), unscheduled DNA synthesis (UDS), and sister chromatid exchanges (SCEs); these are all measures of genotoxicity, as opposed to mutagenicity because they are not themselves transmissible from cell to cell or generation to generation. Genotoxicity also encompasses the mechanisms by which DNA damage occurs and the cellular responses to that damage. All of these effects can be assessed directly by measuring the interaction of agents with DNA or more indirectly through the assessment of DNA repair or the production of gene mutations or chromosome alterations. Standardized assay outcomes that detect mutations in populations of cells and/or organisms have been applied to systematic hazard classifications of chemicals under the United Nations Globally Harmonized System of Classification and Labelling of Chemicals (GHS). Under GHS, the chemical hazards associated with germ cell mutagenicity are assigned to one of two hazard categories: (1) substances known to induce heritable mutations (subcategory 1A) or regarded as if they induce heritable mutations (subcategory 1B) in the germ cells of humans; and (2) substances which cause concern that they may induce heritable mutations in the germ cells of humans (UN, 2015).