Worm Breeder's Gazette 4(1): 40a
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.
At 25 C the isx-1(hc17ts) mutation abolishes spermatogenesis in hermaphrodites, making them females,and causes males to develop as sterile intersexes (Nelson et al., Dev. Biol.66: 386-409, 1978). I found that a double mutant strain, HC17E364, maintained itself at 16 C or 20 C as a population with half males. Subsequently a mutation was segregated from the double that when combined with hc17ts abolishes spermatogenesis in hermaphrodites at all temperatures but leaves males fertile at 16 C or 20 C. Therefore this strain maintains itself as an ordinary gonochoristic species, with separate males and females, at 16 or 20 C. At 25 males are intersex and sterile. The second mutation has been tentatively assigned to a new gene gch which appears to be linked to chromosome II, but precise mapping is not complete. The genetics has been frustrating because the female phenotype of isx,gch is suppressed to varying degrees by most standard morphological markers. In the presence of isx the female phenotype of gch is semi- dominant and shows a partial maternal effect. It is intriguing that apparently only two mutations are necessary to convert C. elegans from a hermaphrodite to a gonochoristic species.