title: A new mathematical model for relative quantification in real-time RT-PCR.
abstract: Use of the real-time polymerase chain reaction (PCR) to amplify cDNA products reverse transcribed from mRNA is on the way to becoming a routine tool in molecular biology to study low abundance gene expression. Real-time PCR is easy to perform, provides the necessary accuracy and produces reliable as well as rapid quantification results. But accurate quantification of nucleic acids requires a reproducible methodology and an adequate mathematical model for data analysis. This study enters into the particular topics of the relative quantification in real-time RT-PCR of a target gene transcript in comparison to a reference gene transcript. Therefore, a new mathematical model is presented. The relative expression ratio is calculated only from the real-time PCR efficiencies and the crossing point deviation of an unknown sample versus a control. This model needs no calibration curve. Control levels were included in the model to standardise each reaction run with respect to RNA integrity, sample loading and inter-PCR variations. High accuracy and reproducibility (<2.5% variation) were reached in LightCycler PCR using the established mathematical model.
authors.affiliation: Institute of Physiology, FML-Weihenstephan, Center of Life and Food Sciences, Technical University of Munich, Germany. pfaffl@weihenstephan.de
authors.forename: M W
authors.initials: MW
authors.lastname: Pfaffl
mesh_terms: D000818:Animals; D017931:DNA Primers; D005786:Gene Expression Regulation; D008962:Models, Theoretical; D012333:RNA, Messenger / Q000032:analysis; D012015:Reference Standards; D015203:Reproducibility of Results; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000592:standards; D012680:Sensitivity and Specificity; D013997:Time Factors; D014158:Transcription, Genetic
chemical_list: D017931:DNA Primers; D012333:RNA, Messenger