Abstract: Method and composition for detecting one or more selected polynucleotide regions in a target polynucleotide. In one embodiment of the invention, a plurality of different-sequence probe pairs are added to a target polynucleotide, where each probe pair includes two polynucleotide probe elements which are complementary in sequence to adjacent portions of a selected one of the target sequences in the target polynucleotide. In each probe pair, one of the probe elements contains a non-polynucleotide polymer chain which imparts a distinctive mobility to the associated probe pair, when the elements in the pair are ligated. The other element in the pair contains a detectable reporter label. After the probe pairs have been allowed to hybridize with the target polynucleotide, the hybridized polynucleotides are treated under conditions effective to ligate the end subunits of target-bound probe elements when their end subunits are base-paired with adjacent target bases.

Abstract: An electrophoresis separation medium is disclosed comprising a matrix of a copolymer composed of a linear hydrophilic polymer segment having a selected substantially uniform segment length and hydrophobic polymer segments carried on each end. Also disclosed is an electrophoresis method employing the separation medium which permits high resolution separation of polynucleotides, especially in DNA sequencing operations.

Abstract: Method and composition for detecting one or more selected polynucleotide regions in a target polynucleotide. In the method, a mixture of sequence-specific probes are reacted with the target polynucleotide under hybridization conditions, and the hybridized probes are treated to selectively modify those probes which are bound to the target polynucleotide in a base-specific manner. The resulting labeled probes include a polymer chain which imparts to each different-sequence probe, a distinctive ratio of charge/translational frictional drag, and a detectable label. The labeled probes are fractionated by electrophoresis in a non-sieving matrix, and the presence of one or more selected sequences in the target polynucleotide are detected according to the observed electrophoretic migration rates of the labeled probes in a non-sieving medium.