The technique of DNA fingerprinting detects a large number of independent hypervariable minisatellite loci throughout the genome in a single hybridization experiment and is an extremely powerful and sensitive means for genetic analysis of very many animal and plant species (a broad overview is given in ref. 1 ). This technique commonly involves the labeling of DNA probes by incorporation of 32 P-tagged nucleotides and autoradiography. However, in some species, such as pigs (2 ) and Galapagos iguanas (K. Rassmann, personal communication and unpublished results), or in cases where only small amounts of DNA on Southern blots are available, greater sensitivity is needed to produce scorable and informative banding patterns. In addition, to make the method suitable for routine screening or processing of large numbers of samples it should be easy to perform, low in health risk, quick, and cheap.