Worm Breeder's Gazette 2(2): 21
These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.
A series of dpy-5 mutations have been induced using gamma irradiation. WiId type (+/+) hermaphrodites were treated with 7500R and mated to heterozygous males. These males are wild type over a double mutant, for example ++/dpy-5 unc-13 or ++/dpy-5 unc-15. After 18 hours of mating individual hermaphrodites were placed on separate plates for 24 hours. WiId type progeny were removed and these plates were screened for exceptional 'dpy' individuals in the F1. Under these conditions four 'dpys' have been found. Two more were found by gamma irradiating +/+ males with 6500R and crossing to homozygous double mutants (dpy-5 y-5 , 000 wiId type male progeny screened, 6 hermaphrodite dpys were found, giving a forward mutation rate of 6/22,000 for the dpy-5 gene under the above conditions. This is within a factor of 2 of the EMS rate proposed by Brenner for any gene (Brenner, 1974). Each of these exceptional 'dpy's' have been tested as a putative deficiency. The two generated at 6500R behaved like point mutations in the dpy-5 gene. The four generated at 7500R segregate chromosomes which are homozygous lethal and have been named Df(I) dpy-5k2...k5. These appear to be affecting a lethal site as well as the dpy-5 gene. In none of these cases has lethal site successfully been separated from the dpy-5 site by recombination. The above data suggests k2...k5 may be X-ray induced deficiencies of the dpy-5 gene and surrounding region. Further evidence that these strains carry a deficiency in the dpy-5 region was derived from crosses between these lines. It is hoped that these deficiencies will provide a useful tool for the genetic analysis of this region. This work was supported by the National Research Council of Canada.