An algorithm for unwarping multitrack electrophoretic gels

Abstract
An algorithm is proposed for removing the effect of “frowns” and “smiles” (i.e. warping) from multitrack electrophoretic gels, so that the bands are horizontal and in alignment between tracks. It has been applied to a DNA sequencing autoradiograph, but could equally be applied to other types of gel separation where warping occurs. The algorithm uses a gradient filter to estimate band orientations. These are smoothed and interpolated by robust regression, and integrated to find the unwarping transform. No manual intervention is required.