Technology
A modified polymerase chain reaction (PCR) technique in which a specific primer can amplify its corresponding allele only; this allows for the determination of the presence or absence of a single, specific allele during genotype testing.
Diagnostic Methods
Technology
A technique designed to rapidly enrich and amplify targets derived from samples that yield low levels of nucleic acids, such as formalin-fixed paraffin-embedded (FFPE) tissues, for use in next-generation sequencing. Briefly, total nucleic acid or genomic DNA (gDNA) is isolated from fresh or FFPE tissues. Total nucleic acid is converted to double-stranded cDNA (dscDNA) and cleaned by solid-phase reversible immobilization (SPRI). Then the dscDNA or gDNA is subjected to end repair, adenylation and ligation with a universal half-functional adapter. The modified DNA sample is then subjected to two rounds of nested low-cycle PCR, where the first round uses target gene-specific primers and the second round uses nested target gene-specific primers that are 5' tagged with a common sequencing adapter. The resulting target amplicon library is cleaned using SPRI and is suitable for use in next generation genomic assays.
Diagnostic Methods
Technology
A molecular genetic technique that isolates and sequences chromosomal regions that are rich in open chromatin. First, nuclei are harvested from a cellular sample. Then a hyperactive Tn5 transposase is added to the nuclei where it excises non-nucleosomal DNA strands and ligates co-administered high-throughput sequencing adapters (tagmentation). The tagged DNA fragments are isolated, amplified by PCR and sequenced. The number of reads for specific region of DNA correlate with increased chromatin accessibility and this method can identify regions of transcription factor and nucleosome binding.
Diagnostic Methods
Technology
A DNA sequencing technique that can differentiate cytosine from 5-methylcytosine in a DNA sample. First, a denatured DNA sample is treated with bisulfite which converts non-methylated cytosine to uracil. Next, the sample is amplified using a PCR method that does not discriminate between non-methylated and methylated sequences. The amplified DNA is subjected to nucleotide sequencing. The resulting sequence is compared to an identical control sample of DNA that was not treated with bisulfite. Unmethylated cytosines will be displayed as cytosines in the control sample and as thymines in the bisulfite-treated sample.
Diagnostic Methods
Technology
Compare liquid and lyophilized reagents by storage requirements, shipping stability, shelf life and procurement readiness.
Cold Chain Stability
Technology
A type of polymerase chain reaction technique in which the sample is fractionated, within which individual PCR reactions occur in each fraction.
Diagnostic Methods
Technology
Check PCR instrument compatibility by fluorescence channels, reaction format support, software fit and validation effort.
Instrument Compatibility
Technology
Check assay-to-instrument fit by fluorescence channels, reaction format and software compatibility across installed PCR platforms.
Instrument Compatibility
Technology
Understand internal, positive, negative and external controls for reliable PCR testing, inhibition monitoring and audit-ready QC workflows.
Internal Control Qc
Technology
Evaluate limit of detection, precision, repeatability and evidence strength for PCR product validation, tenders and procurement review.
Lod Precision Performance
Technology
A type of nucleic acid amplification test in which sample DNA is exposed to a single temperature in the presence of multiple sets of primers and a polymerase with replication and high strand displacement activity. This test negates the need for thermal cyclers and may be a low cost alternative to PCR.
Diagnostic Methods
Technology
A type of high-throughput, multiplex PCR method used to determine abnormal DNA copy number changes of up to 50 genomic DNA or RNA sequences with a single pair of PCR primers. It is frequently used in the detection of genetic aberrations in tumors, and can distinguish sequences differing in only a single nucleotide.
Diagnostic Methods