Automated Image Analysis for Dna Fingerprinting

Methods for automated detection of DNA restriction fragments resolved on agarose fingerprinting gels are described. We present a mathematical model for the location and shape of the restriction fragments as a function of fragment size, with model parameters determined empirically from marker lanes containing molecular size standards. Automated identification of restriction fragments involves several steps, including: image preprocessing, to put the data in a form consistent with a linear model; marker lane analysis, for determination of the model parameters; and data lane analysis, a procedure for detecting restriction fragment multiplets while simultaneously determining the amplitude curve which describes band amplitude as a function of mobility. In validation experiments conducted on fingerprinted and sequenced Bacterial Artificial Chromosome (BAC) clones, sensitivity and specificity of fragment identification exceeded 96% on fragments ranging in size from 600 base pairs to 30k base pairs.