Development of a possible nonmammalian test system for radiation-induced germ-cell mutagenesis using a fish, the Japanese medaka (Oryzias latipes)

Journal Article · Fri Mar 15 00:00:00 EST 1991 · Proceedings of the National Academy of Sciences of the United States of America; (USA)

DOI:https://doi.org/10.1073/pnas.88.6.2545· OSTI ID:5704037

Shima, A; Shimada, A ^[1]

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1. Univ. of Tokyo (Japan)

To develop a specific-locus test (SLT) system for environmental mutagenesis using vertebrate species other than the mouse, we first established a tester stock of the fish medaka (Oryzias latipes) that is homozygous recessive at three loci. The phenotypic expression of these loci can be easily recognized early in embryonic development by observation through the transparent egg membrane. We irradiated wild-type males with 137Cs gamma-rays to determine the dose-response relationships for dominant lethal and specific-locus mutations induced in sperm, spermatids, and spermatogonia. Through observation of 322,666 loci in control offspring and 374,026 loci in offspring obtained from 0.64-, 4.75-, or 9.50-Gy-irradiated gametes, specific-locus mutations were phenotypically detected during early development. These putative mutations, designated total mutation, can be recognized only in embryos of oviparous animals. The developmental fate of these mutant embryos was precisely followed. During subsequent embryonic development, a large fraction died and thus was unavailable for test-crossing, which was used to identify viable mutations. Our medaka SLT system demonstrates that the vast majority of total mutations is associated with dominant lethal mutations. Thus far only one spontaneous viable mutation has been observed, so that all doubling calculations involving this endpoint carry a large error. With these reservations, however, we conclude that the quantitative data so far obtained from the medaka SLT are quite comparable to those from the mouse SLT and, hence, indicate the validity of the medaka SLT as a possible nonmammalian test system.

• OSTI ID: 5704037
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (USA), Vol. 88:6; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
FISHES
MUTAGEN SCREENING
GENE MUTATIONS
RADIOINDUCTION
SPERMATOGONIA
GENETIC RADIATION EFFECTS
CESIUM 137
DOMINANT MUTATIONS
DOSE-RESPONSE RELATIONSHIPS
EMBRYOS
GAMMA RADIATION
LETHAL MUTATIONS
PHENOTYPE
SPERMATOZOA
ALKALI METAL ISOTOPES
ANIMALS
AQUATIC ORGANISMS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BIOLOGICAL RADIATION EFFECTS
CESIUM ISOTOPES
ELECTROMAGNETIC RADIATION
GAMETES
GENETIC EFFECTS
GERM CELLS
IONIZING RADIATIONS
ISOTOPES
MUTATIONS
NUCLEI
ODD-EVEN NUCLEI
RADIATION EFFECTS
RADIATIONS
RADIOISOTOPES
SCREENING
VERTEBRATES
YEARS LIVING RADIOISOTOPES
560152* - Radiation Effects on Animals- Animals