Patent ID: 7273700

Claim:
A nucleic acid probe for determining one or more types of target nucleic acids, comprising a single-stranded nucleic acid being labeled with plural fluorescent dyes, the fluorescent dyes comprising at least one pair of fluorescent dyes to induce fluorescence resonance energy transfer (FRET), the pair of fluorescent dyes comprising a fluorescent dye (a donor dye) capable of serving as a donor dye and a fluorescent dye (an acceptor dye) capable of serving as an acceptor dye, wherein said acceptor dye is BODIPY 581/591 or x-rhodamine, with the proviso that: when the acceptor dye is BODIPY 581/591, the donor dye is one fluorescent dye selected from the group consisting of BODIPY FL, BODIPY 493/503, 5-FAM, Tetramethylrhodamine, and 6-TAMRA, or a combination thereof, and when the acceptor dye is x-rhodamine, the donor dye is one fluorescent dye selected from the group consisting of BODIPY FL, BODIPY 493/503, Tetramethylrhodamine, and 6-TAMRA, or a combination thereof wherein the nucleic acid probe has a base sequence and is labeled with the fluorescent dyes such that the fluorescence intensity of the donor dye and the acceptor dye decrease upon hybridization with a target nucleic acid, wherein said nucleic acid probe is labeled with a donor dye at a 5′- or 3′-end containing cytosine and said nucleic acid probe is labeled with an acceptor dye such that the distance between the bases labeled with the donor dye and the acceptor dye is from 0 to 35 bases, and wherein the site of the end labeling is one group selected from the group consisting of the 3′-hydroxyl of ribose or deoxyribose of the 3′-end containing cytosine, the 5′-hydroxyl of ribose or deoxyribose of the 5′-end containing cytosine, and the 5′phosphate group of the 5′-end containing cytosine.