Journal of Molecular Medicine

, Volume 84, Issue 11, pp 901–910 | Cite as

Quantitative real-time RT-PCR data analysis: current concepts and the novel “gene expression’s CT difference” formula

  • Jan H. Schefe
  • Kerstin E. Lehmann
  • Ivo R. Buschmann
  • Thomas Unger
  • Heiko Funke-Kaiser
Review

Abstract

For quantification of gene-specific mRNA, quantitative real-time RT-PCR has become one of the most frequently used methods over the last few years. This article focuses on the issue of real-time PCR data analysis and its mathematical background, offering a general concept for efficient, fast and precise data analysis superior to the commonly used comparative CT (ΔΔCT) and the standard curve method, as it considers individual amplification efficiencies for every PCR. This concept is based on a novel formula for the calculation of relative gene expression ratios, termed GED (Gene Expression’s CT Difference) formula. Prerequisites for this formula, such as real-time PCR kinetics, the concept of PCR efficiency and its determination, are discussed. Additionally, this article offers some technical considerations and information on statistical analysis of real-time PCR data.

Keywords

Quantification Expression ratio PCR efficiency TaqMan SYBR Green 

Notes

Acknowledgements

The authors would like to thank Dave Hancock and Justin Cross for critically reading the manuscript.

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  • Jan H. Schefe
    • 1
  • Kerstin E. Lehmann
    • 2
  • Ivo R. Buschmann
    • 2
  • Thomas Unger
    • 1
  • Heiko Funke-Kaiser
    • 1
  1. 1.Center for Cardiovascular Research (CCR)/Institute of Pharmacology and ToxicologyCharité-Universitätsmedizin BerlinBerlinGermany
  2. 2.Center for Cardiovascular Research (CCR), Department of Cardiology, Experimental and Clinical Arteriogenesis, CharitéUniversitätsmedizin BerlinBerlinGermany

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