摘要:
Aspects of the present invention provide a method and apparatus of generating a calibration matrix for a spectral detector instrument. A calibration plate contains one or more dye mixtures in each well of the calibration plate at known absolute concentration. From the calibration plate, aspects of the present invention are used to prepare a concentration matrix based on the dyes used in the assay and the different dye mixtures used in the calibration plate. An excitation source exposes the calibration plate causing the spectral species in each of the wells to fluoresce. The emission spectra for the different dye mixtures of dyes as gathered by the spectral detector instrument at different points in the range of spectra is used to generate a spectral matrix. Bilinear calibration is performed on the concentration matrix and the spectral matrix as to determine a calibration matrix relating spectra directly to absolute concentrations.
摘要:
The present invention relates to methods and kits for detecting the presence or absence of (or quantitating) target nucleic acid sequences using ligation and amplification. The invention also relates to methods, reagents, and kits that employ addressable portions and labeled probes.
摘要:
A method is provided for genotyping a target sequence at at least two allelic sites by a 5′ nuclease amplification reaction. In one embodiment, the method includes performing a nucleic acid amplification on a target sequence having at least two different allelic sites using a nucleic acid polymerase having 5′→3′ nuclease activity and a primer capable of hybridizing to the target sequence in the presence of two or more sets of allelic oligonucleotide probes wherein: each set of allelic oligonucleotide probes is for detecting a different allelic site of the target sequence, each set of allelic oligonucleotide probes includes two or more probes which are complementary to different allelic variants at the allelic site being detected by the set of probes, the allelic site being 5′ relative to a sequence to which the primer hybridizes to the target sequence, and at least all but one of the allelic oligonucleotide probes include a different fluorescer than the other probes and a quencher positioned on the probe to quench the fluorescence of the fluorescer; detecting a fluorescence spectrum of the amplification;calculating a fluorescence contribution of each fluorescer to the fluorescence spectrum; anddetermining a presence or absence of the different allelic variants at the two or more different allelic sites based on the fluorescence contribution of each fluorescer to the combined fluorescence spectrum.
摘要:
Disclosed is a method for determining the number of repeat units in a repeat region of a target nucleic acid. In a first aspect, the method of the invention includes the steps of annealing a primer to a target nucleic acid; performing a first primer extension reaction using a first primer extension reagent; separating the target-primer hybrid and unreacted first primer extension reagent; performing a second primer extension reaction using a second primer extension reagent, wherein at least one of the first or second primer extension reagents includes an extendible nucleotide having a label attached thereto; separating the target-primer hybrid from unreacted second primer extension reagent; measuring a signal produced by the label; treating the label so as to render the label undetectable; and repeating the above steps until the signal is substantially less than a signal detected in a previous cycle. In a second aspect, the method of the invention includes the steps of annealing a primer to a target nucleic acid; performing a first primer extension reaction using a first primer-extension reagent; separating the target-primer hybrid from unreacted first primer extension reagent; performing a second primer extension reaction using a second primer extension reagent and with a primer termination reagent, the primer termination reagent including a nucleotide terminator having a label attached thereto; separating the target-primer hybrid from unreacted second primer extension reagent and unreacted primer termination reagent; measuring a signal produced by the label; and repeating the above steps until a signal is detected indicating incorporation of the nucleotide terminator. The invention further includes kits useful for practicing the above methods.
摘要:
Disclosed are methods for detecting or quantifying one or more target polynucleotide sequences in a sample. In one aspect, a sample is contacted with first and second probe pair that are capable of hybridizing to a selected target sequence and a corresponding complementary sequence, respectively. Probe cleavage and ligation results in the formation of ligation products which can be generated in an exponential fashion when the target sequence and/or complement are present in the sample. In another embodiment, a single probe pair can be used to form ligation product in a linear fashion from a complementary template. Reagents and kits are also disclosed.
摘要:
Methods of nucleic acid amplification with external controls are provided that verify the absence or presence of specific target sequences, and correct primers and probes. A single-stranded, external control polynucleotide is amplified with primers of the same sequence as target primers. Probes with detectable labels and sequences specific for target and external control polynucleotides allow for detection and measurement. The primers and the detectable probe are adjacent or substantially adjacent when hybridized to the external control polynucleotide. Target and control amplicons may be detected by increased fluorescence induced by polymerase-mediated 5′ nuclease cleavage or hybridization of a self-quenching probe complementary to both target and external control polynucleotides. A kit of PCR reagents can be dispensed into vessels for rapid and accurate nucleic acid amplification assay, with real-time or end-point measurements. The amplification control reagents, kits, and methods of the present invention provide positive and negative control tests which can be conducted concurrently with target amplification. Allelic differences at genetic loci can be detected, including single nucleotide polymorphisms (SNP).
摘要:
Provided is a method of nucleic acid amplification. In one embodiment, the method comprises performing nucleic acid amplification on a target polynucleotide using a nucleic acid polymerase having 5′ to 3′ nuclease activity, a primer capable of hybridizing to the target polynucleotide, and an oligonucleotide probe under amplification conditions such that the probe hybridizes to the target polynucleotide 3′ relative to the primer and the probe does not hybridize with itself to form a hairpin structure. The oligonucleotide probe has at one end a fluorescent reporter and at the other end a quencher that quenches the fluorescence of the reporter molecule when both the fluorescent reporter and quencher are attached to the probe. Digestion of the oligonucleotide probe by the polymerase during amplification is effective to separate the reporter from the quencher, whereby a fluorescence signal of the reporter is increased.
摘要:
A hybridization assay is provided which uses an oligonucleotide probe which includes a fluorescent reporter molecule and a quencher molecule capable of quenching the fluorescence of the reporter molecule. The oligonucleotide probe is constructed such that the probe exists in at least one single-stranded conformation when unhybridized where the quencher molecule is near enough to the reporter molecule to quench the fluorescence of the reporter molecule. The oligonucleotide probe also exists in at least one conformation when hybridized to a target polynucleotide where the quencher molecule is not positioned close enough to the reporter molecule to quench the fluorescence of the reporter molecule. By adopting these hybridized and unhybridized conformations, the reporter molecule and quencher molecule on the probe exhibits different fluorescence signal intensities when the probe is hybridized and unhybridized. As a result, it is possible to determine whether the probe is hybridized or unhybridized based on a change in the fluorescence intensity of the reporter molecule, the quencher molecule, or a combination thereof. In addition, because the probe can be designed such that the quencher molecule quenches the reporter molecule when the probe is not hybridized, the probe can be designed such that the reporter molecule exhibits limited fluorescence until the probe is either hybridized or digested.