Patent ID: 7632639
Filing Date: 2009-12-15
Classification: C12Q

Abstract:
1. A signal amplification method for detecting a mutated gene, comprising: a first step for hybridizing a capture probe and a first probe to a target DNA; a second step for joining the capture probe and the first probe by a ligation reaction with a DNA ligase when the target DNA has a mutation site that is complementary to the capture probe; a third step for removing the target DNA; a fourth step for adding a plurality of pairs of oligonucleotide probes to form a self-assembly substance by a self-assembly reaction of the oligonucleotide probes so that signal amplification is achieved; and a fifth step for conducting detection of the mutated gene by detecting the presence of the self-assembly substance, wherein the base sequences of the capture probe and the first probe are constructed such that, in the first step, the capture probe and the first probe are annealed to the target DNA in the state where an end of the capture probe hybridizes at the mutation site of the target DNA and the end is adjacent to the first probe, and at least one of the plurality of oligonucleotide probes has a region complementary to the first probe, wherein the self-assembly reaction comprises the steps of: providing the plurality of pairs of oligonucleotide probes comprising n (n≧3) regions, each region of one probe of the pair of oligonucleotide probes being complementary to a corresponding region of the other probe of the pair of oligonucleotide probes; and hybridizing the pairs of oligonucleotide probes such that the one probes and the other probes of the pairs of oligonucleotide probes cross each other in alternation, wherein the oligonucleotide probes are self-assembled to form the double-stranded self-assembly substance.