Non-destructive, enhanced collection and recovery from difficult forensic samples, improving the "front end" processes of DNA typing

As submitted by the proposer:

Improved collection of low template samples (LTS) with subsequent DNA recovery, stable storage and optimized DNA extraction are critical aspects of successful downstream DNA analyses. LTS are inherently sensitive to poor collection and recovery processes. The potential to improve collection from difficult or rough surfaces can provide resolution in criminal cases, exonerate the innocent, and lead to increases in public safety and cumulatively, to society.

This new technology has a clear application in the investigation of property crimes and robbery that involve transfer of LTS or touch DNA from the criminal to some surface. The researchers will use a Venturi vacuum device (VVD) and novel dissolvable fibers to assess improved collection and release of cellular material from touch samples. Proper storage protocols are critical to ensure sample stability over time for re-testing of current and future systems.

The researchers seek to improve outcomes for DNA typing for LTS and challenging forensic samples by optimizing the "front end" of evidence collection from difficult and rough substrates. The first goal will investigate collection and recovery of cellular material through testing the prototype VVD that aspirates material from LTS from rough surfaces where a swab is suboptimal for collection. Different collection matrices for the VVD will be tested to assess their ability to capture and release cellular material compared to standard methods.

Enhancing storage capabilities using biostability reagents before and after DNA extraction will enhance reliable DNA typing results. The researchers will also test currently available methods as well as new DNA extraction technologies that may be applicable to many evidence samples with low template, compromised DNA.

Finally, the researchers will test the optimized protocols on actual touch samples from rough surfaces from 100 individuals as well as non-probative evidence samples. ANOVA and multivariate analyses from all samples will provide the significance and evaluate the improvement of new methods. There is a high-potential for a synergistic effect whereby improvements to all three aspects of the process increases the probability of turning low level, sub-optimal biological DNA samples into samples that fall within the standard forensic DNA testing range.

Dissemination will be through peer reviewed manuscripts, presentations and workshops at meetings, NIJ reports, and possible development of new intellectual property (e.g., collection kits) whose technology can directly transfer to the forensic community. By improving the "front end," optimized STR typing results are produced downstream.

Note: This project contains a research and/or development component, as defined in applicable law, and complies with Part 200 Uniform Requirements - 2 CFR 200.210(a)(14).

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