Front-End Differentiation of Contributor Cell Populations and Estimation of DNA Content Using Novel Cellular Signatures, 2020-2024 (ICPSR 39293)
Principal Investigator(s): View help for Principal Investigator(s)
Christopher Ehrhardt, Virginia Commonwealth University
This is an external resource to which ICPSR links as a courtesy. These data are not available from ICPSR. Users should consult the data owners (via Front-End Differentiation of Contributor Cell Populations and Estimation of DNA Content Using Novel Cellular Signatures, 2020-2024) directly for details on obtaining these resources.
Summary View help for Summary
The objective of this project is to develop a new method for screening trace biological samples for the number of contributors and DNA content based on the presence and relative abundance of key protein and hormone targets within cell populations. There is a critical need for presumptive techniques that could provide valuable information and enable more effective triaging of casework samples, particularly touch samples. To address this, we developed a novel workflow for analyzing biological evidence samples that (1) estimates on the number of contributors in a mixture based upon flow cytometry histogram profiles, (2) estimates the human-specific DNA content in the sample based upon fluorescent signal intensities, and (3) differentiates cell populations in the mixture based contributor-specific attributes. The primary advantage of using this approach with our novel signatures is that all aspects of the proposed workflow are inherently non-destructive. This is ideal for touch evidence samples since these are typically compromised and low in template quantity.
The aims and scope of this project specifically address three operational requirements identified by the 2019 Forensic Technology Working Group: (1) Biological evidence screening tools that can address number and proportion of contributors, (2) ability to differentiate and selectively analyze DNA and/or cells from multiple donors or multiple tissue/cell types contributing to mixtures, with minimal or no sample loss, and (3) comprehensive, systematic, well-controlled studies that provide both foundational knowledge and practical data about "touch evidence" DNA transfer and persistence in the real world.
Data associated with this study are available for download under two separate DOIs:
- Supplemental Electropherogram Data
- Morphological and Autofluorescence Dataset for 'Touch' Epidermal Cell Populations