Patent ID: 7166715

Claim:
A labelled oligonucleotide comprising: an oligonucleotide; and a reporter-quencher energy-transfer dye pair comprising a reporter dye and quencher dye wherein the quencher dye is an asymmetric cyanine dye compound having the structure: and including any associated counter ions, wherein: n ranges from 0 to 2; X is O, S or Se; R 1 is selected from the group consisting of methyl and a linking group, or when taken together with the proximate carbon of the methine bridge forms a ring structure having from 5 to 7 members; R 2 is a linking group; R 3 is hydrogen, or when taken together with R 4 forms a fused aromatic bridge substituted with one or more nitro groups; R 4 is hydrogen, or when taken together with either R 3 or R 5 forms a fused aromatic bridge substituted with one or more nitro groups; R 5 is nitro, or when taken together with either R 4 or R 6 forms a fused aromatic bridge substituted with one or more nitro groups; and R 6 is hydrogen, or when taken together with either R 5 forms a fused aromatic bridge substituted with one or more nitro groups.