Homogeneous assay system using the nuclease activity of a nucleic acid polymerase
First Claim
Patent Images
1. A process for the detection of a target nucleic acid sequence in a sample, said process comprising:
- (a) contacting a sample comprising single-stranded nucleic acids with an oligonucleotide containing a sequence complementary to a region of the target nucleic acid and a labeled oligonucleotide containing a sequence complementary to a second region of the same target nucleic acid sequence strand, but not including the nucleic acid sequence defined by the first oligonucleotide, to create a mixture of duplexes during hybridization conditions, wherein the duplexes comprise the target nucleic acid annealed to the first oligonucleotide and to the labeled oligonucleotide such that the 3'"'"' end of the first oligonucleotide is upstream of the 5'"'"' end of the labeled oligonucleotide;
(b) maintaining the mixture of step (a) with a template-dependent nucleic acid polymerase having a 5'"'"' to 3'"'"' nuclease activity under conditions sufficient to permit the 5'"'"' to 3'"'"' nuclease activity of the polymerase to cleave the annealed, labeled oligonucleotide and release labeled fragments; and
(c) detecting and/or measuring the release of labeled fragments.
3 Assignments
0 Petitions
Accused Products
Abstract
The present invention is directed to a process of detecting a target nucleic acid using labeled oligonucleotides. This process uses the 5'"'"' to 3'"'"' nuclease activity of a nucleic acid polymerase to cleave annealed labeled oligonucleotide from hybridized duplexes and release labeled oligonucleotide fragments for detection. This process is easily incorporated into a PCR amplification assay.
-
Citations
38 Claims
-
1. A process for the detection of a target nucleic acid sequence in a sample, said process comprising:
-
(a) contacting a sample comprising single-stranded nucleic acids with an oligonucleotide containing a sequence complementary to a region of the target nucleic acid and a labeled oligonucleotide containing a sequence complementary to a second region of the same target nucleic acid sequence strand, but not including the nucleic acid sequence defined by the first oligonucleotide, to create a mixture of duplexes during hybridization conditions, wherein the duplexes comprise the target nucleic acid annealed to the first oligonucleotide and to the labeled oligonucleotide such that the 3'"'"' end of the first oligonucleotide is upstream of the 5'"'"' end of the labeled oligonucleotide; (b) maintaining the mixture of step (a) with a template-dependent nucleic acid polymerase having a 5'"'"' to 3'"'"' nuclease activity under conditions sufficient to permit the 5'"'"' to 3'"'"' nuclease activity of the polymerase to cleave the annealed, labeled oligonucleotide and release labeled fragments; and (c) detecting and/or measuring the release of labeled fragments. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A polymerase chain reaction (PCR) amplification process for detecting a target nucleic acid sequence in a sample, said process comprising:
-
(a) providing to a PCR assay containing said sample, at least one labeled oligonucleotide containing a sequence complementary to a region of the target nucleic acid, wherein said labeled oligonucleotide anneals within the target nucleic acid sequence bounded by the oligonucleotide primers of step (b); (b) providing a set of oligonucleotide primers, wherein a first primer contains a sequence complementary to a region in one strand of the target nucleic acid sequence and primes the synthesis of a complementary DNA strand, and a second primer contains a sequence complementary to a region in a second strand of the target nucleic acid sequence and primes the synthesis of a complementary DNA strand; and
wherein each oligonucleotide primer is selected to anneal to its complementary template upstream of any labeled oligonucleotide annealed to the same nucleic acid strand;(c) amplifying the target nucleic acid sequence employing a nucleic acid polymerase having 5'"'"' to 3'"'"' nuclease activity as a template-dependent polymerizing agent under conditions which are permissive for PCR cycling steps of (i) annealing of primers and labeled oligonucleotide to a template nucleic acid sequence contained within the target sequence, and (ii) extending the primer wherein said nucleic acid polymerase synthesizes a primer extension product while the 5'"'"' to 3'"'"' nuclease activity of the nucleic acid polymerase simultaneously releases labeled fragments from the annealed duplexes comprising labeled oligonucleotide and its complementary template nucleic acid sequences, thereby creating detectable labeled fragments; and (d) detecting and/or measuring the release of labeled fragments to determine the presence or absence of the target sequence in the sample. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37)
-
-
38. The PCR process of 37 wherein avidin or streptavidin is attached to the solid phase and the labeled oligonucleotide further comprises a bound biotin molecule separated from the label by a nuclease susceptible cleavage site.
Specification