The National Institute of Justice’s (NIJ) Forensic Technology Center of Excellence (FTCOE), led by RTI International, provides valuable resources that promote the use of technologies in the forensic community. Differential extraction is a technique that allows for the selective cell lysis and isolation of DNA from a mixture of sperm and epithelial cells, predominantly used with evidence collected from sexual assaults where a victim and suspect are not of the same sex. This method aids in the primary means by which a forensic laboratory processes evidence for sexual assault investigations. However, the manual conventional technique was developed 36 years ago,1 is labor intensive, and may lead to poor DNA recovery. This landscape study reviews the conventional differential extraction methodology and its associated challenges, technology solutions that are commercially available and in development, and current research that will advance differential extraction and sperm separation techniques. The estimated pricing for products in this report is current as of 2021. Please contact the vendor directly for updated pricing.
1Gill, P., Jeffreys, A.J., and Werrett, D.J. "Forensic Application of DNA Fingerprints." Nature 318 (1985): 577–79.
Funding for this Forensic Technology Center of Excellence report was provided by the National Institute of Justice, Office of Justice Programs, U.S. Department of Justice.
The opinions, findings, and conclusions or recommendations expressed in this report are those of the author(s) and do not necessarily reflect those of the U.S. Department of Justice.
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