[Mutagenic effect of thioTEPA in laboratory mice. V. Influence of female genotype on realization of dominant lethal mutations induced in the spermatids of males].

Hybrid male mice (F1 males derived from the cross DBA/2 x AKR) were injected intraperitoneally with thio-TEPA at a 2 mg/kg dose. The mutagenic effect was determined from the frequency of dominant lethal mutations induced in spermatids of males. The males were mated during the second and the third week after the injection to females of the strains C57BL/6, CBA/lac and to the F1 hybrid females derived from the cross CBA x C57BL/6 differing in the frequency of spontaneous and induced aberrations in bone marrow cells. In the course of investigation of pregnant C57BL/6 females F1 (CBA x C57BL/6) and CBA/Lac females the frequency of dominant lethals induced in late spermatids was established to be 63.4, 54.0 and 37.9% respectively. The differences were interpreted as the evidence of different rates of recovery of a certain proportion of premutational lesions of the chromosomes of pserms in fertilized egg cells of female mice. No significant differences between the groups of females were observed in case of the treatment of early spermatids. It is establihsed that the F1 hybrids derived from the cross DBA/2 x AKR are characterized by a high mutability.