Radiation-Induced Lymphomas in MSM, (BALB/cHeA x MSM) F_1 and (BALB/cHeA x STS/A) F_1 Hybrid Mice

摘要

M.MOL-MSM (MSM) mice derived from Mus musculus molossinus progenitors showed extreme resistance to the induction of lymphomas following whole-body X-irradiation with four doses of 1.7 Gy. (BALB/cHeA x MSM) F_1 mice between a high lymphoma strain, BALB/cHeA and the MSM showed a high incidence of radiation-induced lymphomas which was quite similar to that in BALB/cHeA mice, but the latent period was prolonged in the hybrids. Susceptibility in incidence was dominant over resistance in these crosses. Incidences of (BALB/cHeA x MSM)F_1 hybrids irradiated with four doses of 2.5 Gy X-rays were 77% in females and 88% in males. F_1 hybrids between BALB/cHeA and another resistant strain STS/A, (BALB/cHeA x STS/A) F_1, also showed a high level of susceptibility, that is, lymphoma incidence was 64% in females and 63% in males. The mean latent period in the (BALB/cHeA x STS/A) F_1 hybrids was similar to that in (BALB/ cHeA x MSM) F_1 hybrids. As all cases of tumors developed in F_1 hybrids are informative concerning the detection of the loss of heterozygosity in the loci depending on the combination of two parental strains, the radiation-induced lymphomas obtained from (BALB/ cHeA x MSM) F_1 and (BALB/cHeA x STS/A) F_1 hybrids could be useful for fine analysis of the genetic alterations involved in lymphomagenesis.