Automatic Interpretation of Digital Autoradiograph of DNA Sequencing Gels

An image processing system has been developed for sequencing DNA gels by digital autoradiography. A multi-wire proportional counter (MWPC) images DNA band patterns which form tracks on an electrophoresis gel. Algorithms have been developed to interpret the MWPC image to obtain a DNA sequence. The algorithms include: (1) a dynamic programming procedure for track detection; (2) a maximum entropy deconvolution algorithm for smoothing and sharpening the image, and (3) a procedure for assigning the correct band sequence. The sequence produced by this method can be confirmed by human operators working from conventional film autoradiographs. The algorithm is being evaluated on various gels and methods for incorporating the knowledge base are currently being investigated. With these improvements we expect the system will approach the performance of expert sequencers.