David Lee Stockton, 65698 E 135Th Pl, Glenpool, OK 74033

6653082, Nov 25, 2003

May 16, 2002

10/150051

David W. Stockton - Houston TX

Baylor College of Medicine - Houston TX

C12Q 168

435 6

Assays for analyzing a sample comprising nucleic acid are described, in which the sample is contacted with an array comprising a set of oligonucleotides attached to a solid support at identifiable locations, wherein each oligonucleotide in the set comprises a label at the distal end of the oligonucleotide; incubating the contacted array to allow hybridization of nucleic acid in the sample to the oligonucleotides of the array; subjecting the hybridized array to a cleavage agent which cleaves incompletely hybridized oligonucleotides but does not cleave completely hybridized oligonucleotides; washing the cleaved array; and assessing a pattern of negative and positive signals on the washed, cleaved array, wherein a negative signal corresponds to an incompletely hybridized oligonucleotide that was cleaved by the cleavage agent, thus removing the label, and a positive signal corresponds to an oligonucleotide that was not cleaved by the cleavage agent, thus retaining the label.