Patent ID: 7252947

Claim:
A molecular torch for use in detecting the presence of a target nucleic acid sequence in a sample, said molecular torch comprising: a target binding domain comprising nucleotide base recognition groups; a target closing domain comprising nucleotide base recognition groups, wherein said target binding domain is biased toward said target sequence, such that said target binding domain forms a more stable hybrid with said target sequence than with said target closing domain under the same assay conditions, and wherein said molecular torch does not detectably hybridize under hybridization conditions to said target sequence when said target binding domain is hybridized to said target closing domain; a label associated with said target binding domain or said target closing domain, wherein said label produces a first signal when said target binding domain:target closing domain hybrid is formed and a second signal when said target binding domain:target closing domain hybrid is not formed, said first and second signals being distinguishable; and an unlabeled joining region comprising one or more non-nucleotide linkers, wherein said joining region joins said target binding domain and said target closing domain, and wherein said joining region facilitates the formation of a target binding domain:target closing domain hybrid in the absence of said target sequence.