FAQ-2688
How can I predict the percent qPCR signal due to contaminating DNA, for a given qPCR assay, and its matching NRT control?
Assuming 100% amplification efficiency, each step increase in Ct value represents a doubling in the amount of qPCR template. Therefore, evaluating the difference in Ct values between the qPCR assay, and its matching NRT control, leads to the following predictions:
| CtNRT - Ct+RT | Fraction of gene expression signal due to contaminating DNA | Percentage of gene expression signal due to contaminating DNA |
| 1 | (1/21) = 1/2 | 50% |
| 2 | (1/22) = 1/4 | 25% |
| 3 | (1/23) = 1/8 | 13% |
| 4 | (1/24) = 1/16 | 6% |
| 5 | (1/25) = 1/32 | 3% |
Related products
RT2 SYBR® Green qPCR Mastermixes
RT2 SYBR Green qPCR Mastermixes are highly suited for real-time PCR applications using SYBR Green, and are required for guaranteed qPCR performance of the RT2 qPCR Primer Assays, RT2 Profiler PCR Arrays, RT2 lncRNA qPCR Assays, and RT2 lncRNA PCR Arrays. This Mastermix should be used in qPCR instruments under standard cycling conditions. RT2 SYBR Green qPCR Mastermixes are also suitable for use with EpiTect ChIP and EpiTect Methyl II qPCR Assays and PCR Arrays.
RT2 Profiler PCR Arrays
RT² Profiler PCR Arrays enable quick, reliable gene expression analysis of 170+ pathways, allowing researchers to spend less time at the bench and more time interpreting results. The arrays are pathway-focused panels of laboratory-verified qPCR assays, with integrated, patented controls to ensure a successful experiment every time. PhD-trained application specialists are available to provide technical support for the arrays, and each array can also be modified to suit unique experimental needs. For biomarker discoveries, we offer Pathway Plus PCR arrays and all arrays listed below for the Fluidigm BioMark Real-Time PCR System.
Housekeeping Genes
RT2 Profiler Array Housekeeping Genes PCR Arrays are used to screen for potential normalization genes for use in real-time PCR analysis. Housekeeping genes encode proteins that are usually essential for the maintenance of cellular function and often remains constant under most experimental conditions. With this array, you can easily profile the expression of twelve (12) commonly used housekeeping genes in eight (8) samples using SYBR-green based qPCR.
RT2 qPCR Primer Assays
RT² qPCR Primer Assays are specifically designed and experimentally verified for real-time PCR analysis. The rigorous assay verification criteria ensure PCR specificity and efficiency for reliable and accurate gene expression analysis results.
QuantiFast SYBR® Green PCR Kit
The QuantiFast SYBR Green PCR Kit delivers fast and specific quantification of gDNA or cDNA targets by real-time PCR or two-step RT-PCR using SYBR Green I detection. Q-bond technology and an optimized, ready-to-use master mix enable shorter real-time PCR run times, not only on fast cyclers with short ramping times, but also on standard cyclers. The combination of a hot start and a unique PCR buffer system in the ready-to-use master mix ensures highly sensitive qPCR on any real-time cycler without the need for optimization. For convenience, the master mix can be stored at 2–8°C.
IMPORTANT NOTE: As announced earlier, the production of the QuantiFast kits has been discontinued since mid-2021. Hence, these products will be available only until stocks last. Visit the product page of the successor kit to view improved features or to request a trial kit.
For more information and FAQs on this transition, visit: www.qiagen.com/PCRresource.
QuantiTect PCR Kits
QuantiTect PCR Kits (qPCR kits) enable sensitive quantification of gDNA and cDNA targets by real-time PCR and two-step RT-PCR using sequence-specific probes or SYBR Green I detection. The real-time PCR kits also allow reliable quantification of up to 5 gDNA or cDNA targets in a single tube by multiplex, real-time PCR or two-step RT-PCR. The combination of a hot start and a unique PCR buffer system in the ready-to-use master mix ensures highly sensitive qPCR on any real-time cycler without the need for optimization. The dNTP mix includes dUTP, allowing optional treatment with UNG. For convenience, the master mixes in QuantiTect PCR Kits can be stored at 2–8°C. Two kit formats are available for multiplex PCR using sequence-specific probes: the QuantiTect Multiplex PCR Kit for cyclers that require ROX dye for fluorescence normalization, and the QuantiTect Multiplex PCR NoROX Kit for all other cyclers.