We have the CyO balancer with LacZ driven by the hunchback promoter and I want
to do PCR on the non-balancer homozygotes which are lethal but will survive
until late embryo. Thus I need a very reliable method for X-gal staining
which does not make the chromosomes unusable for PCR. I'm told there is
a very simple method but I haven't been able to find it as yet. Obviously
it must be reliable due to the contamination potential for PCR. Thanks it
advance for your help.