Worm Breeder's Gazette 8(3): 7
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.
We have begun an analysis of the left half of LGV using recessive lethals, balanced over eT1, which were generated with low doses of gamma radiation or EMS (Rosenbluth, Cuddeford and Baillie, Mutation Research 110: 39-48,1983). At present, the breakpoints of five 1500 R induced deficiencies divide the region balanced by eT1 into 9 zones. [See Figure 1] To date the distribution of lethal mutations relative to these zones is as follows. (Inter-se complementation tests for mutations in the same zone have not yet been carried out;) [See Figure 2] These preliminary results indicate that the distribution of lethal mutations on LGV(left) follows that of the 'visible' genes. Over half the mutations lie within zones 6 to 9,-i.e. in the 'visible' gene cluster. An additional 1500R induced lethal is being analyzed. The mutation s741 is to the left of unc-46. When no longer balanced over eT1, it recombines with unc-46, giving an apparent map distance of 10 m.u., which would place it between unc-60 and dpy-11. However, s741 is complemented by sDf's 28, 27 and 26. Furthermore, the apparent recombination distance between unc-60 and dpy-11 in s741/unc-60 dpy-11 heterozygotes is reduced from the normal 18 m.u. to 10 m.u. Therefore s741 is associated with a dominant crossover suppressor that affects the unc-60 to dpy-11 region. The recessive lethality may be due to a mutation that has a hypermorphic effect, or one that lies to the left of sDf28.Cloning of the unc-60 s underway, employing BO/N2 Tc1 polymorphisms. We hope to correlate soon the developing lethal map with the recombinant DNA map.
