PCR-based DNA typing is a very powerful technique for the analysis of biological evidence. PCR methods enable scientists to replicate a small amount of DNA obtained from minute stains millions of times. The amplified portion represents a particular variable region of the DNA, which may be analyzed by electrophoresis, a method used for separat-ing molecules according their size and electrical charge.
PCR has many advantages over traditional methods, such as restriction fragment length polymorphism (RFLP) analysis, which include:
PCR methods have been extensively validated by the scientific community and have a history of acceptance by courts throughout the country. Population studies have demonstrated that, in combination, these powerful tests can provide discrimination potentials in excess of 99.9%
Forensic Analytical provides high quality PCR-based DNA typing services and court qualified expert testimony to both the criminal and civil legal communities. Forensic Analytical's skilled experts are committed to accurate, reliable and timely results. Currently available PCR tests include the DQA1, Polymarker, and short tandem repeat (STR) loci.
Short Tandem Repeats (STRs) and Automated DNA Typing
Forensic Analytical has remained committed to being a technology leader and employing the most advanced techniques in DNA typing. Among the most recent advancements in the field of DNA typing is the ability to simultaneously analyze multiple genetic markers referred to as short tandem repeats (STRs). The analysis of multiple STR loci can increase discrimination potentials to values formerly achieved only by RFLP analysis. Analysis of STR loci is facilitated by the ability to label PCR products with fluorescent dyes which may be detected with capillary electrophoresis instruments such as the PE Applied Biosystems Prism 310 Genetic Analyzer. The sophisticated instrumentation and automation aids in the interpretation of analytical data and reduces the possibility of errors due to human handling. The AmpFl STR Profiler Plus kit utilized by Forensic Analytical affords the ability to simultaneously type nine STR loci and the sex marker, amelogenin. Specific markers include:
Forensic Analytical, 3777 Deport Road Suite 409, Hayward, CA 94545. Tel: 800-827-3274; Fax: 510-887-4218.