Accession Number : ADA190455
Title : Radiation-Induced Germ Cell Mutations-Their Detection and Modification.
Descriptive Note : Technical rept. 1 Apr 83-30 Jun 87,
Corporate Author : CALIFORNIA UNIV SAN FRANCISCO
Personal Author(s) : Goldstein, Lawrence S.
Report Date : 30 JUN 1987
Pagination or Media Count : 80
Abstract : Mutagenesis by densely ionizing radiation represents a significant long-term hazard to the individual. Few data are available to describe the dose-response aspect of mutation induction by either accelerated charged particles or fission spectrum neutrons in mammalian germ cells. To address this question, an in vitro assay of dominant lethal mutations was undertaken for animals exposed to either of these radiation sources. Special emphasis was placed on the action in spermatogonial stem cells. The data indicate that mutations were induced as a linear function of dose and there was no evidence of a threshold. Mutagenesis was also detected in females given x-radiation. The induction curve had an initial steep linear aspect and then a less steep slope. As with male germ cells, there was no evidence of a threshold. The in vitro dominant lethal data were compared to various cytogenetic assays and were found to be more sensitive indicators of mutation. In preliminary studies, the rate of stable mutagenic damage appeared to be modifiable by pretreatment with chemotherapeutic drugs. Because the radiation sources chosen for this study are thought to be the most efficient for mutation induction, the values obtained may describe the upper limits of exposure for this endpoint. As applied to risk estimation, these data should be considered relative to the normal risk encountered and accepted by the population at large. Keywords: Exposure(Physiology), Irradiation.
Descriptors : *GERM CELLS, *MUTATIONS, *RADIATION EFFECTS, ACCELERATED TESTING, ANIMALS, ASSAYING, BLOOD CELLS, CELLS(BIOLOGY), CHARGED PARTICLES, DOSAGE, ESTIMATES, EXPOSURE(GENERAL), FEMALES, FISSION NEUTRONS, GRAPHS, HAZARDS, IN VITRO ANALYSIS, INDICATORS, IONIZING RADIATION, IRRADIATION, LETHALITY, LINEARITY, LONG RANGE(TIME), MALES, MAMMALS, POPULATION, RADIATION, RESPONSE(BIOLOGY), RISK, SENSITIVITY, SOURCES, SPECTRA, EXPOSURE(PHYSIOLOGY), PHYSIOLOGICAL EFFECTS, RADIOPROTECTIVE AGENTS, RADIATION DOSAGE.
Subject Categories : RADIOBIOLOGY
Distribution Statement : APPROVED FOR PUBLIC RELEASE