The Collection, Preservation, and Processing of DNA Samples from Decomposing Human Remains for More Direct Disaster Victim Identification (DVI)

• NCJ Number: 309932
• Author(s): Amy Sorensen Holmes
• Date Published: 2018
• Length: 244 pages
• Grant Number(s): 2015-R2-CX-0029
• Agencies: NIJ-Sponsored
• Publication Type: Thesis/Dissertation; Research (Applied/Empirical)
• Award: Improved sample collection and preservation of DNA from decomposing human remains; A direct PCR approach for faster disaster victim identification (DVI)

Annotation

This study investigates the collection, preservation, and processing of DNA samples from decomposing human remains for more direct disaster victim identification (DVI).

Abstract

This doctoral research focuses on testing various in-field DNA collection and room temperature preservation methods for decomposing human remains as mock DVI samples. The researcher compared rapid DNA purification protocols or direct amplification approaches that will eliminate unnecessary steps in the DNA analysis workflow, increasing the throughput and reducing the costs of analysis. Overall, results indicate that sufficient DNA can be collected and preserved at ambient temperature using some of these methods, provided that DNA is not already severely degraded before collection. The researcher proposed a method for triaging swab samples based on the quantification results of samples prepared for direct PCR in order to increase the first-pass success rate. Results indicate that foam swabs used to collect from muscle tissue may generate the most complete STR profiles for the majority of decomposed tissues, with cotton swabs yielding similar results. In addition, aliquots of TENT containing DNA leached from tissues were successfully diluted and directly added to the PCR reaction, thereby skipping DNA extraction and quantification all together. This protocol is the quickest of all methods tested, generating STR profiles in a fraction of the time it takes for traditional DNA processing. The researcher found that this method generated the most complete STR profiles from severely decomposed tissues. This research demonstrated that tissues preserved in a modified TENT buffer or collected and stored using cotton and foam swabs show potential as alternate methods for the immediate in-field collection and preservation of DNA at room temperature for human identification purposes. However, these methods warrant further investigation to optimize protocols to achieve more efficient DNA preservation and higher STR success rates from severely decomposed human tissues.