REST 2005
REST-384
beta version 2 [ August 2006 ]
REST-RG beta software version 3 [ August 2006 ]=> download here: rest-rg-beta-9august2006.zip
Real-time
quantitative
polymerase-chain-reaction
(qPCR) is a standard technique in most
laboratories used for various applications in
basic research. Analysis of qPCR data is a crucial
part of the entire experiment, which has led to
the development of a plethora of methods. The
released tools either cover specific parts of the
workflow or provide complete analysis solutions.
Here, we surveyed 27 open-access software packages
and tools for the analysis of qPCR data. The
survey includes 8 Microsoft Windows, 5 web-based,
9 R-based and 5 tools from other platforms.
Reviewed packages and tools support the analysis
of different qPCR applications, such as RNA
quantification, DNA methylation, genotyping,
identification of copy number variations, and
digital PCR. We report an overview of the
functionality, features and specific requirements
of the individual software tools, such as data
exchange formats, availability of a graphical user
interface, included procedures for graphical data
presentation, and offered statistical methods. In
addition, we provide an overview about
quantification strategies, and report various
applications of qPCR. Our comprehensive survey
showed that most tools use their own file format
and only a fraction of the currently existing
tools support the standardized data exchange
format RDML. To allow a more streamlined and
comparable analysis of qPCR data, more vendors and
tools need to adapt the standardized format to
encourage the exchange of data between instrument
software, analysis tools, and researchers.
Management and automated analysis of real-time quantitative PCR data Introduction Gene expression analysis is becoming increasingly important in biological research and clinical decision making, with real-time quantitative PCR becoming the method of choice for expression profiling of selected genes. Maturation of chemistry and hardware has made the practical performance of real-time quantitative PCR measurements feasible for most laboratories. However, accurate and straightforward mathematical and statistical analysis of the raw data (cycle threshold values) as well as the management of growing data sets have become the major hurdles in gene expression analyses. Since the software provided along with the different detection systems does not provide an adequate solution for these issues, we developed qBase, a free software program for the management and automated analysis of real-time quantitative PCR data. What is qBase ? qBase is a collection of macros for Microsoft Excel (currently only Windows version) for the management and automated analysis of real-time quantitative PCR data. The program employs a delta-Ct relative quantification model with PCR efficiency correction and multiple reference gene normalization. The qBase Browser allows data storage and annotation by hierarchically organizing real-time PCR runs into projects > experiments > runs. It is compatible with the export files from many currently available PCR instrument softwares and provides easy access to all your data, both raw and processed. The qBase Analyzer contains an easy run (plate) editor, performs quality control and inter-plate calibration, converts Ct values into normalized and rescaled quantities with proper error propagation, and displays results both tabulated and in graphs. The program can handle an unlimited number of samples, genes and replicates, and allows data from multiple runs to be processed together (preceded by an inter-run calibration if required). The possibility to use up to 5 reference genes allows reliable and robust normalization of gene expression levels. qBase allows easy exchange of data between users, and exports tabulated data for further statistical analyses using other dedicated software.
Other qPCR related tools form
our group
geNorm expression stability analysis of candidate reference genes for accurate normalization [Vandesompele et al., Genome Biology, 2002] RTPrimerDB real-time PCR primer and probe database with currently 3439 real-time PCR assays [Pattyn et al., Nucleic Acids Research, 2003] DART-PCR
Experimental validation of novel and conventional approaches to quantitative real-time PCR data analysis
Download Q-Gene software Quantitative real-time PCR represents a highly sensitive and powerful technique for the quantitation of nucleic acids. It has a tremendous potential for the high-throughput analysis of gene expression in research and routine diagnostics. However, the major hurdle is not the practical performance of the experiments themselves but rather the efficient evaluation and the mathematical and statistical analysis of the enormous amount of data gained by this technology, as these functions are not included in the software provided by the manufacturers of thedetection systems. In this work, we focus on the mathematical evaluation and analysis of the data generated by quantitative real-time PCR, the calculation of the final results, the propagation of experimental variation of the measured values to the final results, and the statistical analysis. We developed a Microsoft® Excel®-based software application coded in Visual Basic for Applications, called Q-Gene, which addresses these points. Q-Gene manages and expedites the planning, performance, and evaluation of quantitative real-time PCR experiments, as well as the mathematical and statistical analysis, storage, and graphical presentation of the data. The Q-Gene software application is a tool to cope with complex quantitative real-time PCR experiments at a high-throughput scale and considerably expedites and rationalizes the experimental setup, data analysis, and data management while ensuring highest reproducibility. Muller PY, Janovjak H, Miserez AR, Dobbie Z. Biotechniques 2002 Jun;32(6):1372-1378 Research Group Cardiovascular Genetics, Institute of Biochemistry and Genetics, University of Basel, Switzerland.
In Table 1, the values in the column "Normalized Expression" need to be replaced by the following ones (top to bottom): 2.30E-03, 2.63E-03, 3.92E-03, 2.95E-03, 4.95E-04, 16.79. Additionally, the values in the column "Mean Normalized Expression" need to be replaced by 2.87E-03, 3.26E-04, 11.35. The difference between the two calculation procedures according to Table 2, Equation 2 and 3, respectively, amounts to 2.8%. Furthermore, the corresponding values in the discussion section need to be replaced.
qPCR-DAMS:
a Database Tool to Analyze, Manage, and
Store Both Relative and Absolute Quantitative Real-Time PCR data. Quantitative
real-time PCR is an important high throughput method
in biomedical sciences. However, existing software
has limitations in handling both relative and
absolute quantification. We designed qPCR-DAMS
(Quantitative PCR Data Analysis and Management
System), a database tool based on Access 2003, to
deal with such shortcomings by the addition of
integrated mathematical procedures. qPCR-DAMA allows
a user choose among four methods for data processing
within a single software package: (I) Ratio relative
quantification, (II) Absolute level, (III)
Normalized absolute expression, and (IV) Ratio
absolute quantification. qPCR-DAMS also provides a
tool for multiple reference gene normalization.
qPCR-DAMS has three quality control steps and a data
display system to monitor data variation. In
summary, qPCR-DAMS is a handy tool for real-time PCR
users.
LinRegPCR
LinRegPCR is
a program for the analysis of quantitative RT-PCR
(qPCR) data resulting from monitoring the PCR
reaction with SYBR green or similar fluorescent
dyes. The program determines a baseline
fluorescence and does a baseline subtraction. Then
a Window-of-Linearity is set and PCR efficiencies
per sample are calculated. With the mean PCR
efficiency per amplicon, the Ct value per sample
and the fluorescence threshold set to determnine
the Ct, the starting concentration per sample,
expressed in arbitrary fluorescence units, is
calculated => See below:
Assumption-free analysis of quantitative real-time PCR data Ramakers
C, Ruijter JM, Deprez RH, Moorman AF. (2003)
Neurosci Lett 2003 Mar 13;339(1): 62-66 Department
of Anatomy and Embryology K2-283, Experimental and
Molecular Quantification of
mRNAs using real-time polymerase chain reaction
(PCR) by monitoring the
product formation with the fluorescent dye SYBR
Green I is being extensively
used in neurosciences, developmental biology, and
medical diagnostics. Most
PCR data analysis procedures assume that the PCR
efficiency for the
amplicon of interest is constant or even, in the
case of the comparative C(t)
method, equal to 2. The latter method already
leads to a 4-fold error when the PCR efficiencies vary over just a
0.04 range. PCR efficiencies of amplicons are usually calculated from standard
curves based on either known RNA inputs or
on dilution series of a reference
cDNA sample. In this paper we show that the
first approach can lead to PCR
efficiencies that vary over a 0.2 range, whereas
the second approach may be off by
0.26. Therefore, we propose linear regression
on the Log(fluorescence) per cycle
number data as an assumption-free method to
calculate starting concentrations of
mRNAs and PCR efficiencies for each sample.
The new LinRegPCR version of the program (with an updated manual) can be downloaded => http://LinRegPCR.nl Amplification efficiency: linking baseline
and bias in the analysis of quantitative PCR
data
Despite the central role of quantitative PCR
(qPCR) in the quantification of mRNA transcripts,
most analyses of qPCR data are still delegated to
the software that comes with the qPCR apparatus.
This is especially true for the handling of the
fluorescence baseline. This article shows that
baseline estimation errors are directly reflected
in the observed PCR efficiency values and are thus
propagated exponentially in the estimated starting
concentrations as well as ‘fold-difference’
results. Because of the unknown origin and
kinetics of the baseline fluorescence, the
fluorescence values monitored in the initial
cycles of the PCR reaction cannot be used to
estimate a useful baseline value. An algorithm
that estimates the baseline by reconstructing the
log-linear phase downward from the early plateau
phase of the PCR reaction was developed and shown
to lead to very reproducible PCR efficiency
values. PCR efficiency values were determined per
sample by fitting a regression line to a subset of
data points in the log-linear phase. The
variability, as well as the bias, in qPCR results
was significantly reduced when the mean of these
PCR efficiencies per amplicon was used in the
calculation of an estimate of the starting
concentration per sample.J. M. Ruijter1, C. Ramakers2, W. M. H. Hoogaars1, Y. Karlen3, O. Bakker4, M. J. B. van den Hoff1 and A. F. M. Moorman1 1Heart Failure Research Center, Academic Medical Center, University of Amsterdam, The Netherlands, 2Department of Neuroscience, Faculty of Mental Health, University of Maastricht, The Netherlands, 3Nestec Ltd, PTC Orbe, Switzerland and 4Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, The Netherlands Nucleic Acids Research Advance Access published online on February 22, 2009 The new
LinRegPCR version of the program (with an
updated manual) can be downloaded =>
http://LinRegPCR.nl
Dear LinRegPCR user, We recently updated LinRegPCR to
implement the import and export of RDML
files RDML was developed as a standard for export, exchange, and storage of quantitative PCR data and is supported by several large qPCR system suppliers as well as by data analysis software like qbase-plus. LinRegPCR now forms a link between your qPCR system and such statistical analysis software. LinRegPCR can handle RDML versions 1.0 and 1.1, as well as RDML files in which floating point values are written with decimals points and decimal commas. LinRegPCR will write the analysis results to an RDML file, version 1.1, with decimal points to maintain compatibilty with the current RDML specification. The RDML input option is the main addition to LinRegPCR that was implemented in 2012. There were also several qPCR systems added to the list of input formats from Excel files. For other minor changes in the program, please have a look at the recent updates listed on the LinRegPCR website (http://LinRegPCR.nl). On our site you will also find a link to a recent paper (Ruijter et al., Methods 2012), in which LinRegPCR and other publicly available PCR amplification curve analysis programs were compared. This paper is unique in the field of qPCR because all analysis methods were applied by their original developers, and thus in the currently recommended way. The paper was co-authored by the developers of these curve analysis programs and members of the geNorm team, who performed the statistical analysis. The datasets used for this comparison, and the analysis results, can be downloaded from http://qPCRDataMethods.hfrc.nl. I hope you continue to enjoy the use of LinRegPCR. Best wishes for the coming festive season and your future scientific endeavours, Jan M Ruijter Addressing fluorogenic real-time qPCR
inhibition using the novel custom Excel file
system 'FocusField2-6GallupqPCRSet-upTool-001'
to attain consistently high fidelity qPCR
reactions.
Jack M. Gallup and Mark R. Ackermann Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University. Ames, Iowa 50011-1250. USA. Biol. Proced. Online 2006;8:87-152. The
purpose of this manuscript is to discuss
fluorogenic real-time quantitative polymerase
chain reaction (qPCR) inhibition and to
introduce/define a novel Microsoft Excel-based
file system which provides a way to detect and
avoid inhibition, and enables investigators to
consistently design dynamically-sound, truly
LOG-linear qPCR reactions very quickly. The
qPCR problems this invention solves are
universal to all qPCR reactions, and it
performs all necessary qPCR set-up
calculations in about 52 seconds (using a
pentium 4 processor) for up to seven qPCR
targets and seventy-two samples at a time –
calculations that commonly take capable
investigators days to finish. We have named
this custom Excel-based file system
"FocusField2- 6GallupqPCRSet-upTool-001"
(FF2-6-001 qPCR set-up tool), and are in the
process of transforming it into professional
qPCR set-up software to be made available in
2007. The current prototype is already fully
functional.
PREXCEL-Q
is not a qPCR data analysis program - it is an
extensive qPCR validation, set-up and
receipe printout program for each step of
the qPCR process; for One-Step, Two-Step and LCM-one
or two-step qPCR Test Plate
set-ups, avoidance of inhibition by proper dynamic dilution
range identificaton and the subsequent final plate
set-ups.
Please see attached Dr. Bustin's letter of endorsement of the program to get a feel for what the program really is. PREXCEL-Q (which is 35 inter-linked Excel files) can only be licensed from Iowa State University by contacting Dr. Dario Valenzuela first at Iowa State University Research Foundation (ISURF) at: dariov@iastate.edu - and then I personally send the 35 files and password to each new user. The ‘PREXCEL-Q Method’ for qPCR Jack M. Gallup, Mark R. Ackermann Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA International journal of Biomedical science 4(4) 2008 The
purpose
of this manuscript is to describe a reliable
approach to quantitative real-time polymerase
chain reaction (qPCR ) assay development and
project management, which is currently embodied in
the Excel 2003-based software program named
“PREXCEL-Q” (P-Q) (formerly known as
“FocusField2-6Gallup-qPCRS et-upTool-001,”
“FF2-6-001 qPCR set-up tool” or “Iowa State
University Research Foundation [ISURF] project
#03407”). Since its inception from 1997-2007, the
program has been well-received and requested
around the world and was recently unveiled by its
inventor at the 2008 Cambridge Healthtech
Institute’s Fourth Annual qPCR Conference in San
Diego, CA. P-Q was subsequently mentioned in a
review article by Stephen A. Bustin, an
acknowledged leader in the qPCR field. Due to its
success and growing popularity, and the fact that
P-Q introduces a unique/defined approach to qPCR,
a concise description of what the program is and
what it does has become important. Sample-related
inhibitory problems of the qPCR assay, sample
concentration limitations, nuclease-treatment,
reverse transcription (RT ) and master mix
formulations are all addressed by the program,
enabling investigators to quickly, consistently
and confidently design uninhibited,
dynamically-sound,
LOG-linear-amplification-capable,
high-efficiency-of-amplification reactions for any
type of qPCR. The current version of the program
can handle an infinite number of samples.
SoFAR: software
for fully automatic evaluation of real-time PCR
data.
Wilhelm J, Pingoud A, Hahn M. Justus-Liebig-Universitat Giessen, Giessen, Germany. Biotechniques. 2003 Feb;34(2):324-32 Quantitative
real-time
PCR has proven to be an extremely useful technique
in life sciences for many applications. Although a
lot of attention has been paid to the optimization
of the assay conditions, the analysis of the data
acquired is often done with software tools that do
not make optimum use of the information provided by
the data. Particularly, this is the case for
high-throughput analysis, which requires a careful
characterization and interpretation of the complete
data by suitable software. Here we present a
software solution for the robust, reliable,
accurate, and fast evaluation of real-time PCR data,
called SoFAR. The software automatically evaluates
the data acquired with the LightCycler system. It
applies new algorithms for an adaptive background
correction of signal trends, the calculation of the
effective signal noise, the automated identification
of the exponential phases, the adaptive smoothing of
the raw data, and the correction of melting curve
data. Finally, it provides information regarding the
validity of the results obtained. The SoFAR software
minimizes the time required for evaluation and
increases the accuracy and reliability of the
results. The software is available upon request.
Validation of an algorithm for automatic quantification of nucleic acid copy numbers by real-time polymerase chain reaction Wilhelm J, Pingoud A, Hahn M. Anal Biochem. 2003 Jun 15;317(2):218-25. Institut fur Biochemie, FB 08, Justus-Liebig-Universitat Giessen, Heinrich-Buff-Ring 58, D-35392 Giessen, Germany.
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