RADIATION-INDUCED CHROMOSOMAL-ABERRATIONS IN THE BONE-MARROW OF MICE EXPOSED TO VARIOUS DOSES OF GAMMA-RADIATION

The occurrence of chromosomal aberrations was studied at 1-14 days pos t-exposure in female BALB/c mice exposed to various doses of gamma rad iation. The frequency of abnormal cells, chromatid and chromosome brea ks, dicentrics, centric rings, acentric fragments and total aberration s increased with exposure dose, and it was highest at 7 Gy. A peak was recorded on day 1 post-exposure with a gradual decline thereafter. Th e chromosomal aberration yield reached a nadir on day 14 post-irradiat ion, without restoration to the control level. The best fit for the pr esent data was by a linear-quadratic relationship between dose of radi ation and the frequency of chromosomal aberrations.