Patent ID: 7354716

Claim:
A method for detecting at least one specific RNA molecule in a population comprising a plurality of different RNA molecules, said method comprising: (a) making a hybrid template comprising a first portion and a second portion, wherein said first and second portion of said hybrid template are operably linked, and wherein the first portion is an RNA sequence complementary to an internal sequence of said specific RNA molecule and said second portion is a DNA sequence complementary to a region proximal to the internal sequence of said specific RNA molecule; (b) binding said hybrid template to said specific RNA molecule, wherein said binding produces a complex comprising said specific RNA molecule and said hybrid template and said binding results in formation of a double stranded RNA/RNA duplex at the internal sequence of said specific RNA molecule and a double stranded RNA/DNA duplex at the region proximal to the internal sequence of said specific RNA molecule; (c) digesting said complex with a riboendonuclease capable of digesting double-stranded RNA/DNA duplexes, wherein said digesting cleaves said specific RNA molecule at the region proximal to the internal sequence and leaves intact double stranded RNA/RNA duplex at the internal sequence to produce a digested complex comprising a truncated specific RNA molecule and bound hybrid template; (d) performing an extension of said digested complex, wherein said hybrid template acts as a template for extension of the truncated specific RNA molecule and said extension incorporates at least one detectable label into an extended RNA molecule; and (e) detecting a presence of the at least one detectable label in said extended RNA molecule, wherein said presence of said at least one detectable label in said extended RNA molecule provides a positive indicator for detecting a specific RNA molecule in a population comprising a plurality of different RNA molecules.