task often necessary when working with 2 dimensional electrophoretic
gels is finding
similarities between the two gels. By overlaying different gels in an
appropriate way it is possible to naturally investigate the similarity
between two gels.
The image presents the 'best possible overlay' of two
gel images. The red spots are from one gel, the blue spots are from
another gel. Places where the color of the spot is black instead of
blue or red show locations where the two spots match. In the picture
some of these spots are marked with a red circle.
Based on this kind of overlays it is further possible to group large sets of
gels automatically into clusters based on their overlay similarities.