Patent ID: 8097418

Claim:
A method for the detection of at least one oligonucloetide probe on a microarray comprising: a) contacting a microarray having thereon at least one oligonucleotide probe with at least one labeled target cDNA molecule; b) incubating said microarray and said labeled target cDNA molecule for a time and at a temperature sufficient to enable said labeled target cDNA molecule to hybridize to said oligonucleotide probe; c) washing said microarray to remove unhybridized labeled target cDNA; and d) detecting the signal from the hybridized labeled target cDNA molecule, thereby detecting at least one oligonucloetide probe on a microarray, wherein the at least one target cDNA molecule is produced by a method comprising: e) providing at least one first round single stranded cDNA molecule having a 5′ end and a 3′ end; f) attaching an oligodeoxynucleotide tail onto the 3′ end of said first round cDNA molecule; g) annealing to said oligodeoxynucleotide tail a single stranded promoter template comprising a first RNA polymerase recognition sequence and at least a second different RNA polymerase recognition sequence 3′ to said first recognition sequence, wherein said single stranded promoter template is not extendable with DNA polymerase; h) extending said oligodeoxynucleotide tail such that said single stranded promoter template is converted into a first RNA polymerase promoter and at least a second RNA polymerase promoter 3′ to said first promoter; i) initiating a first round of RNA transcription using an RNA polymerase which recognizes said first RNA polymerase promoter to produce at least one first round sRNA molecule; j) synthesizing at least one second round single stranded cDNA molecule from said first round sRNA molecule; k) degrading said first round sRNA molecule; l) annealing a single stranded promoter oligonucleotide complementary to said second different RNA polymerase recognition sequence such that a second RNA polymerase promoter is formed; m) initiating a second round of RNA transcription using an RNA polymerase which recognizes said second RNA polymerase promoter to produce the at least one second round sRNA molecule; and n) synthesizing at least one target cDNA molecule from said second round sRNA molecule.