Qualitative and Quantitative Assessment of Single Fingerprints in Forensic DNA Analysis

• NCJ Number: 249311
• Author(s): Lana Ostojic, Stacey A. Klempner, Rosni A. Patel, Adele A. Mitchell, Grace L. Axler-DiPerte, Elisa Wurmbach
• Date Published: November 2014
• Length: 8 pages
• Agencies: NIJ-Sponsored
• Award: Pre-Extraction Separation of Mixed Source DNA Samples through Micromanipulation and Direct PCR Short Tandem Repeat Typing of Cells

Annotation

This study collected and analyzed over 700 fingerprints, comparing a commercially available DNA extraction protocol (Zygem) to two methods developed in a laboratory, a simple one-tube protocol and a high sensitivity protocol (HighSens) that includes additional steps to concentrate and purify the DNA.

Abstract

Fingerprints and touched items are important sources of DNA for STR profiling, since this evidence can be recovered in a wide variety of criminal offenses; however, there are some fundamental difficulties in working with these samples, including variability in quantity and quality of extracted DNA. In the current study, the amplification protocols tested were AmpFLSTR® Identifiler®, using either 28 or 31 amplification cycles, and Identifiler® Plus, using 32 amplification cycles. The study found that the HighSens and Zygem extraction methods were significantly better in their DNA yields than the one-tube method. Identifiler® Plus significantly increased the quality of the STR profiles for the one-tube extraction; however, this effect could not be verified for the other extraction methods. Furthermore, microscopic analysis of single fingerprints revealed that some individuals tended to shed more material onto glass slides than others; however, a dense deposit of skin flakes did not strongly correlate with a high quality STR profile. (Publisher abstract modified)