Comparison of six DNA quantification methods

Six commercial preparations of human genomic DNA were quantified using six quantification methods including UV spectrometry, SYBR-green dye staining, slotblot hybridization with the probe D17Z1, and three TaqMan real-time PCR assays: Quantifilerk Human DNA Quantification kit, Quantifilerk Y DNA Quantification kit, and RB1 rt-PCR. In general, all methods measured higher DNA concentrations than expected based on the information by the suppliers of the human DNA preparations. The Quantifilerk Human DNA Quantification kit gave the highest measures of the DNA concentrations of five of the six human DNA preparations compared to the other five quantification methods. When the Quantifilerk human DNA standard was replaced by a different commercial human DNA preparation (G147A, Promega) to generate the DNA standard curve in the Quantifilerk Human DNA Quantification kit, the DNA quantification results of the human DNA preparations were comparable to those of the other DNA quantification methods. The results indicate a calibration problem with the Quantifilerk human DNA standard for its use with the Quantifilerk Human DNA Quantification kit. The possible reasons of the problem are discussed, and a solution is suggested. The results emphasise the need for standard reference DNA material and standard methods for DNA quantification. D 2005 Elsevier B.V. All rights reserved.