An analysis system for two-dimensional gel electrophoresis images of genomic DNA

The authors have developed an image processing system DNAinsight, which is based on a powerful pattern analysis scheme of autoradiogram images obtained with 2-D (two-dimensional) gel electrophoresis based on the RLGS (restriction landmark genome scanning)method for the purpose of high-speed genome scanning. By this means several thousands of spots are observed as signals: each spot corresponds to a genetic locus and its intensity reflects the copy number of the restriction landmark. Therefore, one of the key problems of image processing for automated analysis is to detect the location of each spot and to measure its intensity. Some kinds of operator including the background normalization and elliptic ring operators are used for solving the problem. And another is to match and compare the RLGS patterns in order to analyze various abnormal states of gene. This is solved by using a fast and robust matching algorithm by means of the Delaunay net and relative neighbourhood graphs with attributes. Some experimental results indicate that the authors´ system is effective enough to put to practical use of RLGS patterns from the viewpoint of accuracy and efficiency