The estimation of the amount or copy number of a specific gene is difficult and dependent on a number of parameters. The accuracy and precision of the measurement relies on the quality of the target nucleic acids as well as the robustness of the measurement protocol. We are focusing on real-time quantitative PCR (polymerase chain reaction) measurements, which utilize intercalating dyes or specific fluorescent-labeled probes for monitoring the amplification of the target DNAs.

• Development of a prototype plasmid-based system for the measurement and calibration of the fluorescent signals with different kinds of fluorescent probes.
• A pilot study with the Bioanalytical Working Group of the CCQM is in progress. We seek to understand the importance of various parameters in the overall accuracy of the measurements.
• CSTL researchers are developing primary methods that provide accurate and traceable measurement of total plant DNA.
• The investigations in CSTL have shown that DNA from corn kernels and soybeans responds differently to the digestion and analysis protocols that work with human DNA.

• M. J. Holden, J. R. Blasic, Jr., L. Bussjaeger, C. Kao, L. A. Shokere, D. C. Kendall, L. Freese, G. R. Jenkins. “Evaluation of extraction methodologies for corn kernel ( Zea mays ) DNA for detection of trace amounts of biotechnology-derived DNA” J . Agr. Food Chem. 2003, 51, 2468-2474.
• C.E. Dawson, F. Qureshi, M.J. Burns, M.J. Holden, J.R. Blasic, Jr., A.J. Woolford, " An Inter-Platform Repeatability Study Investigating Real-time Amplification of Plasmid DNA, " BMC Biotechnology 2005 5, 15..