GENETIC-EFFECTS OF GAMMA-IRRADIATION ON C HIRONOMUS-THUMMI - CHROMOSOME-ABERRATIONS IN MITOTIC CELLS

The frequency of chromosome aberrations in mitotic cells of imaginal d iscs and epipharyngeal ganglion was studied in Chironomus thummi gamma -irradiated at doses of 0.09, 0.9, 9, or 90 Gy. The frequency of cells with chromosome aberrations was shown to be directly proportional to the dose of gamma-irradiation. The chromosome aberration spectrum diff ered from the control only when the irradiation dose exceeded 9 Gy. In the progeny of exposed animals, the spectrum of chromosome aberration s was the same as in the control animals and the frequency of aberrant cells decreased in consecutive generations at a rate depending on irr adiation dose. Analysis of chromosome aberrations in C. thummi mitotic cells can be used to detect exposure to gamma-rays and evaluate irrad iation dose in exposed animals but not in their progeny.