Mouse spot test

Human (occupational exposure) Mouse (spot test)... 

In vivo mammalian mutation tests are not restricted to germ cell tests. The mouse spot test described below is, again, a test used first for studying radiation-induced mutation but has also been used for screening chemicals for in vivo mutagenic potential. This test has had several proponents but compared with in vivo chromosomal assays is not widely used. 

The test marker strain (T) developed by Russell uses seven recessive loci a (nonagouti), b (brown), cch (chinchilla), d (dilute), p (pink-eyed dilution), 5 (piebald) and se (short-ear). As for the mouse spot test, these genes control coat pigmentation, intensity or pattern, and, for the se gene, the size of the external ear. 

Comparison of mutation frequencies is made with the historical database. For definition of a positive result the same principles are recommended as for the mouse spot test (Selby and Olson, 1981). A minimum size of 18,000 offspring per group is recommended by those authors for definition of a negative result. 

Russell, L.B. (1984). Procedures and evaluation of results of the mouse spot test. In Handbook of Mutagenicity Test Procedures (Kilbey, B.J., Legator, M., Nichols, W. and Ramel, C., Eds.). Elsevier, Amsterdam, pp. 393 403. 

Genetic Toxicology Mouse Spot Test (Original Guideline, adopted 23 October 1986)... 

A positive response in the mouse spot test indicates that exposure to the test substance results in an increased frequency of spots of changed color in the coat as a result of heritable gene mutations. 

Mouse spot test, C57BL6JxT miee + 100 pox 3 Lang (1984)... 

Mutations were induced at the hprt locus in mice exposed to butadiene for 6 h per day on five days per week at 625 ppm [1380 mg/m ] for two weeks or at 1300 ppm [2760 mg/m3] for one week. Butadiene was mutagenic in the mouse spot test (500 ppm [1100 mg/m3] 6 h per day for five days) and in two transgenic mouse models. Exposure to 62.5 or 1250 ppm [138 or 2760 mg/m ] butadiene for 6 h per day on five days per week for four weeks increased the frequency of mutations induced at A T base pairs in bone marrow of lad mice, while exposure to 625 ppm for 6 h per day for five days increased the ZocZ mutation frequency in lung but not liver or bone marrow of the MutaMouse . 

MST, Mouse spot test (T x HT)Fi miee 500 ip X 1 Neuhauser-Klaus ... 

Caprolactam treatment in vivo did not increase DNA single-strand breaks in hepatocytes or unscheduled DNA synthesis in spermatocytes of rats, did not induce sister chromatid exchanges, micronuclei or chromosomal aberrations in mouse bone marrow and did not induce morphological abnormalities in mouse sperm. Inconclusive results were reported in two mouse spot test studies for gene mutations. 

In single in-vivo studies, catechol did not induce DNA strand breaks or somatic cell mutations in the mouse spot test (one study). On the other hand, micronuclei were induced in mouse bone marrow (three of four studies). In one of these positive micronucleus test studies, the effect was greater after intraperitoneal injection than after gavage administration, while, in the other positive study, the effect of an intraperitoneal injection was enhanced by either phenol or hydroquinone. 

Mutagenicity of l,2-dibromo-3-chloropropane (DBCP) in the mouse spot test. Mutat. 

Gocke, E., Wild, D.. Eckhardt, K. King, M.T. (1983) Mutagenicity studies with the mouse spot test. Mutat. Res.. 117, 201-212... 

Russell, L.B., P.B. Selby, E. von Halle, W. Sheridan, and L. Valcovic. Use of the mouse spot test in chemical mutagenesis Interpretation of past data and recommendations for future work. Mutat. Res. 86 355-379, 1981. 

Mammalian bone marrow chromosome aberration test (OECD 475) Mouse spot test (OECD 484)... 

Number of Animals. For statistical reasons, about five to ten animals pCT dose group are generally used, except in the case of labor-intensive tests where a minimum of three (e.g., for the UDS test in liver cells) or four animals is reconunended. A much larger number of animals must be used in some assays (e.g., up to 50 dams treated and several hundred Fj animals examined in mouse spot tests). For ethical reasons, such assays are seldom used. Animals should be evaluated individually. 

Fahrig, R. (1995). The mouse spot test. In Environmental Mutagenesis, Phillips, D. H., and Venitt, S., eds.. Bios Scientific PubUshers, Oxford, pp. 180-199. 

OECD (1986b). Genetic toxicology Mouse spot test. OECD Guideline for Testing of Chemicals 484, 1-4. 

Mouse spot test Foetal cell of mouse Mutagenicity in foetal cells B24/TG484... 

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