[Micronucleus and cytogenetic disorders in mouse embryos before implantation].

Studies of mice embryos of different genotypes revealed 4.1% of polyploids, 8.5% of aneuploids and 7.9% of embryos with structural chromosome aberrations. Embryos of lines BAIB and CBA were reliably different in micronuclei occurrence (9.8 and 4.6%). A relation is shown to exist between the presence of micronuclei and structural aberrations. Normalization of the embryo genotype at early stages of embryogeny might occur by means of elimination of cells with disturbances or due to the death of anomalous embryos in the period of implantation.