PROBES FOR NUCLEIC ACID ANALYSIS AND METHOD USING THESE PROBES

A probe for detecting nonradioactive nucleic acids by the hybridization technique, and a highly sensitive and highly selective method for the detection. The probe comprises a set of two or more oligonucleotide probes that can hybridize perfectly complementarily with the specific portion of the sequence of the consecutive bases of the target nucleic acid, each oligonucleotide probe being labeled at the 5' or 3' end thereof with a chromophoric group having a suitable spatial arrangement so that adjacent chromophoric groups can yield an excimer or the like when each probe hybridizes with the target nucleic acid. More specifically, although the probe of the invention comprises a set of two or more labeled probes and the labeling groups to be detected are present each on a different probe, the labeling groups take such a spatial arrangement that the two chromophoric groups present on the two probes which have come to exist adjacent to each other only after the hybridization with the target nucleic acid induce unique phenomena such as excimer fluorescence, thereby enabling the target nucleic acid to be detected with a high recognizability. Thus the probe of the invention enables the erroneous recognition which has been problematic heretofore to be reduced remarkably and the types of utilizable labeling groups to be varied widely. Further it is possible to improve the detection sensitivity remarkably because it is possible to reduce the background noise remarkably. In addition, it is possible to discriminate a number of (singlebase variation) nucleic acids that are different from one another in only one base present at a specific position to be detected, which has been difficult heretofore.