Mammalian cytogenetic tests

Fluothane was negative in two Tier I tests (and not subjected to the third), but was positive in the Drosophila test. If fluothane had also had a negative result in the mammalian cytogenetic test, it would be the only example in this series of a substance that was mutagenic according to the Tier II test but was not detected in Tier I. 

B. 10. Other effects - Mutagenesis (in vitro mammalian cytogenetic test) B. 11. Other effects - Mutagenesis (in vitro mam al bone marrow cytological test, chromosomal analysis)... 

OECD (1983). OECD Guidelines for the Testing of Chemicals. No. 475. Genetic toxicology in vivo mammalian bone marrow cytogenetic test chromosomal analysis. Adopted 4 April 1984. 

Like other cytogenetic tests, SCE tests can be performed on cells treated in culture or in vivo. For the in vivo method, cells from treated animals can be excised and cultured in vitro in the presence of BrdUrd or the animal itself can be given an injection or infusion of BrdUrd so that SCE can be observed in bone marrow or spermatogonial cells directly. The latter method is one of the simplest and least expensive ways to observe the effects of chemicals in gonads. The test is not limited to mammalian cells, but has been successfully carried out in plants, insects, and fish. 

Many chromosomal alterations can be detected in plants,149 and, in addition to studies of mitotic cells, methods using microsporocytes (i.e., pollen mother cells) have permitted the study of meiotic cells.263 Although basic research in plant cytogenetics continues, cytogenetic tests in plants have been replaced to some extent in genetic toxicology by mammalian cell-culture tests and tests in whole mammals. 

Fertility and early embryonic development rats Developmental rats, rabbits Prenatal and postnatal development rats Genetic toxicology Ames test, in vitro mammalian chromosome aberration assay, in vivo cytogenetic test, FIGPRT test with V79 cells... 

This in vitro cytogenetic test is a clastogenicity test system for the detection of chromosomal aberrations in cultured mammalian cells or primary cultures. Chromosomal aberrations may be either structural or numerical. However, because cytogenetic assays are usually designed to analyze cells at their first posttreatment mitosis and numerical aberrations require at least one cell division to be visualized, this type of aberration is generally not observed in a routine cytogenetic assay. The best estimate of aberration frequency is the first cell division after the start of treatment. Structural aberrations are of two types chromosome or chromatid aberrations. 

A test for gene mutations in bacteria An in vitro cytogenetic test in mammalian cells or in vitro mouse lymphoma tk assay... 

Nitrites have tested negative in DNA repair bacterial assays. Positive results have been reported in mammalian cytogenetics and sister chromatid exchange studies. 

AU ehgible chemicals under REACH require the conductance of a bacterial reverse mutation (Ames) test (Annex Vll, 8.4.1) (EC 2006). For compounds >10t/a, an additional mammalian in vitro cytogenetic test is required (Aimex VIII, 8.4.2) (EC 2006). For the latter, both the chromosome aberration test and the micronucleus test in vitro are considered acceptable. In the case of a negative result in the mammalian in vitro cytogenetic test and in the in vitro gene mutation test in bacteria, data from an in vitro gene mutation study in mammahan ceUs are required (Annex... 

In vivo Mammalian Bone Marrow Cytogenetic Test -... 

It must be emphasized that the dominant lethal assay should be applied together with other in vivo- mammalian mutagenicity tests, notably in vivo cytogenetics, karyotype analysis of bone marrow, and the host-mediated assay, in addition to ancillary submammalian tests. Such mammalian systems can be simply and practically incorporated in the course of routine toxicity testing. 

G. E. Ford and E. P. Evans, Meiotic preparations from mammalian testes, in Comparative Mammalian Cytogenetics (R. Benirschke, ed.) pp. 461-464, Springer-Verlag, Berlin, Heidelberg, New York (1969). 

Pati, P.C. and S.P. Bhunya. 1989. Cytogenetic effects of fenvalerate in mammalian in vivo test system. Mutat. Res. 222 149-154. 

The in vitro cytogenetic assay is a short-term mutagenicity test for detecting chromosomal damage in cultured mammalian cells. 

Evans, E.P., Breckon, G. and Ford, C.E. (1964). An air-drying method for meiotic preparations from mammalian testes. Cytogenet. Cell Genet. 3 289-294. 

Natarajan, A.T. and Obe, G. (1982). Mutagenicity testing with cultured mammalian cells cytogenetic assays. In Mutagenicity, New Horizons in Genetic Toxicology, (Heddle, J.A., Ed.). Academic Press, New York, pp. 172-213. 

Under Guideline S2B, the following standard test battery is recommended (1) a test for gene mutation in bacteria, (2) an in vitro test with cytogenetic evaluation of chromosomal damage with mammalian cells or an in vitro mouse lymphoma thymidine kinase (TK) assay, and (3) an in vivo test for chromosomal damage using rodent hematopoietic cells. 

An in vitro test with cytogenetic evaluation of chromosomal damage with mammalian cells OR an in vitro mouse lymphoma thymidine kinase assay... 

Sofuni, T., Hayashi, M., Matsuoka, A., Sawada, M., Hatanaka, M. Ishidate, M., Jr (1984a) Cytogenetic effects of gaseous and volatile chemicals on mammalian cells in vitro and in vivo. 1. Chromosome aberration tests in cultured mammalian cells. Eisei Shikenjo Hokoku, 10, 77-83 (in Japanese)... 

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