Patent ID: 6573048
Filing Date: 2003-06-03
Classification: C12Q

Abstract:
A method for detecting a target nucleic acid sequence in a sample, comprising:(i) combining a sample with a pair of probes under conditions of sequence-specific hybridization, wherein each probe has a target-complementary region capable of base paring to a portion of the target nucleic acid sequence and a probe-probe branch-forming region at either terminus not complementary to said target nucleic acid sequence at a terminus of the probe that is capable of forming via interaction with the other probe a probe-probe branch, at least one crosslinking compound positioned within the probe-probe branch-forming region of one probe which forms a covalent crosslink with a crosslinking compound reactant positioned within the probe-probe branch-forming region of the other probe of the probe pair after base pairing of the probes to said target nucleic acid sequence, and at least one detectable moiety bonded to at least one of the probes; (ii) photoirradiating said sample to crosslink the probe-probe branch-forming region of adjacent pairs of probes; (iii) separating the crosslinked probe-probe branch-forming region of the probes from the target complementary region by degrading the target-complementary region and the target nucleic acid sequence that is base paired to the target-complementary region; and (iv) detecting the presence of at least one separated, crosslinked probe-probe branch as indicative of the presence of said target nucleic acid sequence in said sample.