FINAL by: OSAC Program Office; Version 2, January 13, 2020 1 

OSAC RESEARCH NEEDS ASSESSMENT FORM 

Title of research need: Characterizing the presence and prevalence of cell‐free DNA  

Describe

the need:

Extra cellular, or cell‐free DNA has been widely acknowledged as a potential source of DNA

on evidentiary items. The presence and quantity of this may be most substantial in cases

involving “touch DNA” – where the sample may be composed of nucleated cells and cell‐

free DNA. However, there is limited information as to which is more prevalent and

differences between donors. Often times the questions at court for this type of evidence

focus on activity level propositions. (i.e. Suspect handled the gun directly vs. the gun came

in contact with some intermediary person or item.) A better understanding of this could

lead to improved recovery and storage techniques resulting in better DNA profiles. This

need is related to, but different than, “touch” DNA issues and collection issues.

Keyword(s): Touch DNA, activity level propositions, extra‐cellular DNA, cell‐free DNA

Submitting subcommittee(s): Human Biology Date Approved: 10/05/2021

(If SAC review identifies additional subcommittees, add them to the box above.)

Background Information:

1. Does this research need address a gap(s) in a current or planned standard? (ex.: Field identification system 

for on scene opioid detection and confirmation)

Yes. 

2. Are you aware of any ongoing research that may address this research need that has not yet been published 

(e.g., research presented in conference proceedings, studies that you or a colleague have participated in but 

have yet to be published)?

NA 

3. Key bibliographic references relating to this research need: 

1) Burrill, J., Kombara, A., Daniel, B. & Frascione, N. Exploration of cell-free DNA (cfDNA) recovery for touch 

deposits. Forensic Sci. Int. Genet. 51, 102431 (2021) 

2) Vandewoestyne, M., Van Hoofstat, D., Franssen, A. E., Nieuwerburgh, F. Van & Deforce, D. Presence and 

potential of cell free DNA in different types of forensic samples. Forensic Sci. Int. Genet. 7, 316–320 (2013) 

3) Kumar, M., Choudhury, Y., Ghosh, S. K. & Mondal, R. Application and optimization of minimally invasive cellfree DNA techniques in oncogenomics: https://doi.org/10.1177/1010428318760342 40, 1–12 (2018) 
FINAL by: OSAC Program Office; Version 2, January 13, 2020 2 

4. Review the annual operational/research needs published by the National Institute of Justice (NIJ) at 

https://nij.ojp.gov/topics/articles/forensic-science-research-and-development-technology-working-groupoperational#latest? Is your research need identified by NIJ?

Partially related areas include “Comprehensive, systematic, well-controlled studies that provide both 

foundational knowledge and practical data about "touch evidence" DNA transfer (e.g., primary, secondary) and 

persistence in the real world, as well as best practices for interpretation”; “Improved DNA collection devices or 

methods for recovery and release of DNA” 

5. In what ways would the research results improve current laboratory capabilities? 

Most collection and extraction techniques are designed around intact cellular DNA. This area of research would 

explore improvements in methods for the collection, purification and storage of extra-cellular DNA. A way to 

distinguish between cellular and extra-cellular DNA would be informative when dealing with activity level 

propositions, often the source of disagreement in so-called “touch” DNA cases. 

6. In what ways would the research results improve understanding of the scientific basis for the 

subcommittee(s)? 

This would allow for more focused guidance documents for evaluating DNA evidence when the dispute is about 

the activities that caused DNA to move from A to B. 

7. In what ways would the research results improve services to the criminal justice system? 

Most DNA trials move towards the activity level of the hierarchy of propositions. A better understanding of 

cellular DNA vs. extra-cellular DNA may be helpful in Bayesian Networks for evaluating DNA evidence given 

questions of activity. 

8. Status assessment (I, II, III, or IV): II

Major gap in 

current 

knowledge 

Minor gap in 

current 

knowledge 

 

 No or limited

current research is 

being conducted I III 

 Existing current 

research is being 

conducted II IV 

This research need has been identified by one or more subcommittees of OSAC and is being provided as an

informational resource to the community.