X

Inbr: F89. Albino. Genet: a, B/b, c. Origin: Unknown, but maintained by Goldfeder since 1953.

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Characteristics

No spontaneous tumours of any kind. They are resistant to the induction of tumours by urethane, producing only 3% tumours at dose levels that would induce 80-90% in other strains. Also resistant to tumour induction by X-rays. Combined X-ray and urethane produces only 6% tumours. The mice do not produce murine leukaemia virus antigens in their milk, and are resistant to polyoma virus, Friend leukaemia virus and FBJ osteosarcoma virus. They also have high immune response against sheep erythrocytes, pronounced splenic phagocytic activity, high levels of antibody to mammary tumour virus and a tendency to spontaneous amyloidosis. The low tumour incidence is attributed to high immune competence and absence of an apparent oncogenic virus as revealed by electron microscopy (Goldfeder et al., 1966; Goldfeder, 1972r, 1972). Resistance to carcinogens does not appear to be due to differences in biochemiceal response to such chemicals (Grantham et al., 1976., 1976).

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Goldfeder A., Kauffman S. L., and Ghosh A. K. (1966) Carcinogenesis in naturally tumour-resistant mice. X-irradiation versus urethan as a carcinogenic agent. Brit. J. Cancer 20, 361-374.

Goldfeder A. (1972) Urethan and X-ray effects on mice of a tumor-resistant strain, X/Gf. Cancer Res. 32, 2771-2777.

Grantham P. H., Mohan L. C., and Weisburger E. K. (1976) Metabolism of N-2-fluorenylacetamide in X/Gf mice: lack of correlation between biochemical interaction and carcinogenicity. J. Natl. Cancer Inst. 56, 649-651.

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INBRED STRAINS OF MICE
Updated 9 Apr. 1998
Michael FW Festing
MRC Toxicology Unit, Hodgkin Building,
University of Leicester, UK