CHROMOSOME BREAKS NUMBER AND PROBABILITY OF BREAK REUNION IN IRRADIATED MATURE SPERMATOZOA OF DROSOPHILA-MELANOGASTER

The dose-effect curves for half and full translocations induced in mat ure sperm with the break points within the same chromosomal region wer e obtained. Probability of reunion q and the number of breaks N that c ould be calculated from these curves varies within the range 0.83-0.69 and 0.011-0.078, respectively. The half and full translocations were induced under maternal effect of mus104D1. In this case, q = 0.86 (for normal genotype 0.79) and N = 0.114 (for normal genotype 0.048). Thes e figures show that the dose increase and the introduction of the mus 104 cause increase in the breaks number and only weak change in break reunion occurs. The method developed can be used for the search for mu tations that interfere with break reunion.