Patent ID: 8084206

Claim:
A method for detecting a target nucleic acid, consisting essentially of: (a) contacting a plurality of target-specific nucleic acid probes that are each complementary to a target nucleic acid, to a sample under conditions whereby the plurality of target-specific nucleic acid probes hybridize to the target nucleic acid if the target nucleic acid is present in the sample, wherein upon hybridization to the target nucleic acid, the target-specific nucleic acid probes form a series of target-specific nucleic acid probes directly adjacent to one another, wherein a first target specific nucleic acid probe is capable of binding or is bound to a molecular post and a second target-specific nucleic acid probe is capable of binding or is bound to a detection probe, and wherein the first target-specific nucleic acid probe and the second target-specific nucleic acid probe are positioned at the 5′ and 3′ end, respectively, of the series of target specific nucleic acid probes; (b) binding the molecular post to the first target-specific nucleic acid probe and/or binding the detection probe to the second target-specific nucleic acid probe if the molecular post and/or detection probe were not bound prior to hybridization; (c) ligating the series of target-specific nucleic acid probes together to produce a ligation product; (d) after ligating then binding the molecular post to the first target-specific nucleic acid probe and/or binding the detection probe to the second target-specific nucleic acid probe and forming a concentration gradient of ligation products prior to contacting the ligation products with the molecular post and/or detection probe; (e) treating the ligation product with one or both of: (i) exonuclease digestion; and (ii) denaturation to create all single stranded bridges after ligation; (f) binding the molecular post to the first target-specific nucleic acid probe and/or binding the detection probe to the second target-specific nucleic acid probe if the molecular post and/or detection probe were not bound prior to the step (e) treatment; and (g) then detecting the ligation product.