Artefacts on SDS PA gels

[Ian Ross]

HI - I didn't see the original query but I can verify that these bands 
are almost always due to keratin - usually from human fingers but 
sometimes from the tissue source.  If from humans, the only solution is 
scrupulous cleanliness.  Usually this becomes a problem with silver 
stained gels which of course are so much more sensitive than coomassie 
gels.

Regards

Ian Ross
Centre for Molecular and Cellular Biology
University of Queensland
Australia 4072