NCJ Number
218316
Journal
Forensic Magazine Volume: 4 Issue: 2 Dated: April-May 2007 Pages: 16-24
Date Published
May 2007
Length
6 pages
Annotation
This article describes improved DNA analysis through a new technology for real-time quantitative PCR that offers an advantage over currently available systems by simultaneously quantitating both total human DNA and male-specific DNA within a sample, in addition to an internal PCR control.
Abstract
This technology was developed by Promega and is known as the Plexor HY Quantitation System. It will be available in early 2007. Accurate total human and human male DNA quantitation is a necessary step in the process of forensic DNA typing. Without it, DNA analysts can waste time performing STR analysis on unsuitable samples or reanalyzing failed samples. Current methods used in the field improve on older hybridization-based methods, but still leave room for additional enhancements. The Plexor HY system incorporates many key features, including high sensitivity, internal positive controls, product melt analysis, and simultaneous quantitation of total human and total male DNA. The technology takes advantage of the specific interaction between two modified nucleotides in order to achieve quantitative analysis. The new technology directly measures the change in fluorescent signal in relative fluorescent units at every cycle of the PCR. Existing real-time PCR strategies result in an increased signal as product accumulates. The Plexor HY system results in a decreased signal as product accumulates. Consequently, amplification data continue to present a characteristic three-phase curve. 4 figures and 11 references