Help! Problem with Northern Blots!

[George Rutherford]

In article <PETER.WILSON-1204971212190001 at pc0746.ri.bbsrc.ac.uk>,
PETER.WILSON at BBSRC.AC.UK (pete wilson) wrote:

> Reusing the electrophoresis buffer can cause this effect if the tank has
> previously used with the target molecules of the probe you are using. The
> contaminating molecules enter the gel from the top (-ve) so, if that is
> what is happening, that end of the blot will be black.
> 
> Ian Dunn
> Roslin Institute
> EH25 9PS

Hmmmm... I suppose this is a possibility, but assuming a standard level of
laboratory fastidiousness, as most people seem to employ doing Northerns,
a contaminated tank seems a bit unlikely. I vote for the film having been
'flashed' by an underdrad or a 1st year grad student. Perhaps the PI? :-)

George