Patent ID: 8795966

Claim:
A method comprising the steps of: providing a set of oligonucleotide probes bound to a substrate, wherein each probe comprises a target binding domain, which is complementary to a target nucleic acid; a closing domain with a sequence that is complementary to the sequence of the target binding domain; and a joining region between the binding domain and the closing domain, which is not complementary to the target nucleic acid; wherein the set comprises at least two probes that differ in the sequence of their target binding domain, and wherein the probes are bound to the substrate via the joining region; placing the set of probes in contact with nucleic acid targets under conditions suitable for capture of the target by a probe and formation of a probe-target duplex; generating conditions suitable for enzyme-mediated probe elongation wherein the 3′ terminal end of a probe is elongated if a nucleotide in the target sequence which is aligned with the 3′ terminal end of the target binding domain is complementary; and detecting the increase in cumulative signal associated with each type of probe, resulting from probe elongation.