Worm Breeder's Gazette 2(2): 23a

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.

Title unknown.

Authors unknown.

We shall summarize our work on selecting and characterizing X-ray-
induced chromosomal duplications.  We have also isolated X-ray-induced 
deletions of bits of the X chromosome covered by Dp(X;V)1.  We have 
further characterized two X-ray-induced crossover suppressors for 
linkage group II.  One, called C1, is coupled to dpy-10 and unc-52, is 
homozygous viable, and segregates independently of all other linkage 
groups: it is probably an intrachromosomal rearrangement.
We have used a C1 dpy-10 unc-4 stock to identify 
over 100 EMS induced recessive lethal mutations coupled to unc-4 and 
balanced by the C1 chromosome.  About half of the lethals are 
embryonic or larval.  The rest give sterile adults, some of which are 
rescuable by mating with wild-type males.  Some of the lethals have 
been complemented and mapped.  They tend to map in the cluster of 
Tetraploid stocks, one of which is homozygous for unc-3 and dpy-11, 
have been established.  In agreement with Nigon's earlier work, we 
find that tetraploid hermaphrodites are either high frequency male 
producers (giving roughly 45% males) or low (giving less than 1%).  
Triploids can be produced by crossing tetraploid males by diploid 
hermaphrodites or vice versa.  Triploid hermaphrodites have small 
brood sizes and lay many eggs that do not hatch.  Our results are 
consistent with the following genotypic assignments (where A denotes 
one set of autosomes): 4X/4A, low frequency male producer; 3X/4A, high 
frequency male producer; 2X/4A, male; 2X/3A, male.