[Limited genetic monitoring in Kiev in relation to the accident at the Chernobyl Atomic Electric Power Station].

Frequency of innate developmental defects, perinatal death rate, spontaneous and induced abortions were statistically studied on the basis of primary medical information from archives of two largest maternity hospitals of Kiev for the period between 1969 and 1989. Significant variations in the chosen characters in different years were found, unidirectional changes in time being absent. No increase in the number of innate defects and frequency of spontaneous abortions after 1986 was found.

[Unusual cases of the inheritance of Down's syndrome].

Three unusual cases of Down's syndrome inheritance are presented which permit supposing that microstructural chromosome aberrations in parents may induce not only a structural imbalance of chromosomal material in progeny, but also a numerical imbalance.

[Cytogenetic study of the effect of vaccinia virus on cells from embryo and adult mice].

After immunization with vaccinia virus an increase in frequency of aneuploids and secondary chromosomal constrictions is observed in adult mice. Moreover, an increased frequency of chromosomal aberrations was demonstrated. The increase in the number of secondary chromosomal constrictions indicates an activation of nucleolar-organizing regions.