Worm Breeder's Gazette 9(1): 87

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.

Artificial Insemination

M. Shen and A. Fire

Inspired by a lunchtime conversation with Sam Ward and Tabitha 
Doniach, we decided to attempt artificial insemination of worms by 
injection of sperm.  The recipient animals were females of genotype 
fog-1(e1959) 7) (from a balanced strain provided by 
T.  Doniach; fog - 'Feminization Of Germline').  Any progeny from 
these animals indicates successful insemination; the progeny should be 
non-Unc and half should be male (if sperm from XO parents are used).  
The sperm donors were males from the strain mab-3(e1240); 
67), which were used because they conveniently 
accumulate large quantities of sperm, due to their complete inability 
to mate (Hodgkin, 1983).
We used the current MRC injection procedure, immobilizing the males 
and females under oil on a dried agarose pad.  The males were ruptured 
at their tails by poking with the needle, allowing their sperm to flow 
out.  The sperm were then collected by suction from the needle, which 
had to be rather blunt (large enough to accommodate the sperm).  The 
sperm were then injected through the vulvas of recipient females.  
Unfortunately, it was difficult to count (or even confirm the presence 
of) injected sperm using our injection optics.
In several experiments, we injected a total of 21 Fog 
males, which had been verified as lacking 
fertilized eggs.  A total of 9 animals were fertile, most with 1 to 5 
progeny, and one parent having 18 progeny (10 hermaphrodite and 8 male)
.  We confirmed that the F1 hermaphrodites segregated Fog Unc, Him, 
and wild-type progeny.
We have not yet optimized the conditions for this procedure, but it 
seems clear that it works.  The efficiency of insemination must be 
fairly high, since few sperm are injected into each animal.  This 
procedure should be useful for certain genetic constructs, and for 
testing the sperm found in mutants that are unable to mate.  From 
these experiments, we can already conclude that mab-3 males have 
functional sperm.