Worm Breeder's Gazette 6(1): 29
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.
I have further refined the unc-54 fine structure genetic map since presenting a preliminary map at the worm meeting in 1979. I have used the strategy outlined previously (see CSH abstracts 1979), constructing heteroallelic strains with one allele in cis with lev-11( x12) and the other allele in cis with let-50(st33). The current version of the map is based on more than 600 unc-54(+) chromosomes recovered. Recombination of the outside markers has been used to determine the allele order. Frequencies in general have been ignored in constructing the map, since the number of events used to order any particular pair of alleles is small. Many of the unc-54(+) chromosomes do not contain a recombination of the outside markers, indicating that these are conversion events. Conversion of the e675 allele and e190 allele has also been observed. In the figure below, the alleles mapped reciprocally are shown below the line. Those above the line have been placed in cis only with lev- 11 and mapped against the alleles below the line in cis with let-50. The exceptions to this is e1301, which has been mapped in cis with let- 50 against all alleles, as the lev-11 301) double is too leaky to use effectively. The e675/e190 heteroallelic combination has not yielded any unc-54(+) chromosomes in more than 4x10+E6 events tested. Similarly the e190/e1213 strains have not produced wild types. Thus the e675 and e190 deficiencies are either very close or overlap and e190 may include e1213. [See Figure 1]