Solution-phase single hybridization assay for detecting polynucleotide sequences

Claim 1

A process for determining the presence of a particular nucleic acid sequence in a sample containing cells comprising (a) chemically modifying nucleic acids in an unpurified sample, said sample consisting essentially of whole cells, said whole cells being lysed during the process, cell lysates and mixtures thereof, either to introduce a label or a reactive site, wherein the chemical modification of the sample nucleic acids to introduce said label or said reactive site is accomplished by reaction with a photochemical reagent comprising said label or reactive site, respectively, (b) conducting hybridization, (c) contacting under hybridization conditions the chemically modified sample nucleic acids with a hybridizable nucleic acid probe which either, when the sample nucleic acids have been modified to introduce a label, includes a reactive site, or when the sample nucleic acids have been modified to introduce a reactive site, is labeled, (d) contacting the solution resulting from step (c) with an immobilized form of a reactive site on the sample nucleic acids or the probe, respectively, (e) separating the resulting immobilized fraction from the remaining solution, and (f) determining the presence of the label in the separated immobilized fraction or a decrease in the label in the remaining solution.