*** CAN ANYONE EXPLAIN THIS????***

[Dr Mark Watson]

Hi Netters

I'm having a problem with a DNA digest I'm doing.  I am digesting an 
adenovirus plasmid construct with XmnI which should cut once to 
linearise the plasmid to give a 7.6kb band.  Running the digest out we 
see a 7.6kb band (which is great).


After NaAc / EtoH precipitation I see a 4kb size band on the gel and a 
much weaker 7.6kb band.  After heating the DNA to 90 degrees and slow 
cooling it all appeears to be 4kb.

Lately we are seeing the 7.6kb and 4kb bands in approx equal amounts 
just after digestion ie before EtoH precipitation.

Anyone ever seen this before or have an idea of what is happening.

Cheers all

Mark

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=  Dr Mark W Watson                     email: mwatson at uniwa.uwa.edu.au 
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