> FWIW, I've had just the problems you described trying to do just this:
> determine whether a given deletion takes out my gene of interest. Controls
> were okay, but one of the two deletion lines gives a high level of "dud"
> eggs, which won't amplify with either control or experimental primers.
>> I've now put both deletions over balancers expressing beta-gal, but
> staining so far has been spotty. This may or may not work out, so I may
> also turn to squashes (or just skip it entirely). So, Merav, you might
> want to try something like the beta-gal trick, or yellow or whatever, just
> so you can reliably separate your homozygous-deletion eggs from the
>> Chris Jones
If I had to do it again, i just go straight for the polytene squashes. IMO it's
much faster and more convincing than single embryo PCR or quantitative southern.