Universal probe system for DNA fingerprinting.

A universal probe system is a combination of an unlabeled primary probe that has been inserted in a cloning vector and a labeled secondary probe that is specific to the vector. This system is time- and labor-saving in that one does not need to label probes every time one uses them, so long as they are inserted in the same vector. As a first step in the preparation of a universal probe system for DNA fingerprinting, we isolated multi-locus probes from a subgenomic library that had been constructed by insertion into the phagemid pUC118 of 1-2 kb fragments of DNA from human myeloma cells. Next, we isolated single-stranded DNAs of recombinant phagemids, and hybridized them with Southern blots of DNAs from mother-child-father trios or unrelated individuals. As with double-stranded DNA probes, we were able to detect DNA fingerprints, with a commercially available, alkaline phosphatase-labeled secondary probe or a digoxigenin-labeled universal sequencing primer.