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Gel Electrophoresis Bowed Migration Pattern Troubleshooting - (Nov/25/2006 )


Trying to troubleshoot a DNA Fingerprint 1.5% agarose gel electrophoresis gel- got strange bowing migration pattern where the ends migrated faster than the center lanes. Same molecular marker was used in lanes 1 and 3 in the attached image, which leads me to believe it's a gel problem.

Does anyone have an idea of what might cause this? I've heard this not an entirely uncommon problem?

Thanks for any suggestions!!!


Some things to check:
* has the gel completely set? Perhaps the outside has set and the middle has not.
* are you running the gel hot? High current could cause heating most visible in the center.
* is the gel thickness uniform? A bowed gel tray could cause this.
* Are the electrodes straight and uniform and covered with buffer? Electrode contact at only the edges could cause this.
* Is the buffer covering the gel? Nonuniform buffer thickness could cause this.


In addition to what phage434 has pointed out, try to fill the empty wells with roughly same amount of loading buffer; be sure to reduce the ionic strength of your samples by gel filtration or dialysis method.


Excellent ideas! Thank you guys for your quick and helpful replies!