It has been pointed out that human DNA at a level that can be identified is spread in environmental DNA (eDNA) collected from indoor spaces and environments such as beach sand, and management regulations such as ethics and personal information protection related to the use of eDNA are necessary.

Professor David Duffy's team at the University of Florida (UF) in the United States reported in the scientific journal Nature Ecology & Evolution that they have identified a large number of human DNA from eDNA collected from various environments, and in some cases it has been possible to identify a specific person.

EDNA sampling is a common technique for obtaining genetic information from biological material or fragments of living tissue in terrestrial or aquatic ecosystems.

These eDNA are used for a variety of purposes, including monitoring wildlife populations and invasive alien species, reconstructing historical environments, and testing for pathogens such as the novel coronavirus (SARS-CoV-2) in sewage.

In this study, the team identified human genetic material that was inadvertently taken from various eDNA samples taken from wildlife and pathogen identification projects and named it "human genetic bycatch" (HGB).

The eDNA samples they analyzed were taken from a variety of environments, including water near or far from inhabited areas, human footprints in beach sand, and air in inhabited and unoccupied rooms.

Analysis confirmed that all eDNA samples contained HGB.

Depending on how they were collected, some samples were found to contain DNA of such a high quality that personal information such as the DNA owner's ancestry and disease susceptibility could be identified.

"During this study, we were surprised to find that there was a lot of human DNA in the eDNA, and the quality of that DNA was very high," Duffy said.

The researchers pointed out that being able to accurately analyze the DNA of people, animals, and pathogens in eDNA can be very useful scientifically, but it presents another ethical dilemma.

Professor Duffy said ethically managed eDNA specimens can benefit a wide range of fields, from medicine to environmental science to archaeology to forensic forensics.

Analyzing eDNA in wastewater could track cancer mutations, and investigators could find suspects through DNA floating in the air at crime scenes.

However, the team pointed out that human genetic information identified in eDNA analysis is personal information that should be treated very carefully, and that new rules are needed on how to manage personal information found in such inadvertently collected eDNA.

Natalie Lam, a professor at the University of Maryland who was not involved in the study, said in an accompanying commentary, "This study shows what is possible with new tools for collecting, analyzing, and using genetic data, and requires ethical and legal reflection on how these tools can be used and misused, and how the risk of misuse can be minimized."

(Photo = Courtesy of David Duffy, Yonhap News)