[Reciprocal translocations in mice found in the vicinity of the Chernobyl nuclear power station]

A study was made of the incidence of genetic damage to germ cells of male mice taken from or exposed within the thirty-kilometer zone of Chernobyl, the contaminated no-man's-land around the reactor that failed. At all contamination levels mouse spermatocytes exhibited reciprocal translocations, a relatively low frequency of which increased with increasing dose rate. Heterozygotes, with respect to reciprocal translocations (5%), were found among males exposed to enhanced radiation background as early embryos.