Assessment of cfDNA levels in saliva samples of stressed young adults: Preliminary study

Purpose: The aim of this pilot study was to examine the levels of cell-free DNA (cfDNA) in the saliva samples of second-year medical students before and after a stress-inducing event, exams. Materials and Methods: Saliva samples were collected from 20 students, whose stress profiles were assessed using the DASS-21 scale, both before and after the exams. Cell-free DNA were isolated from these samples, and measured using spectrophotometry and automated electrophoresis system. Results: Spectrophotometric analysis revealed a significant decrease in cfDNA levels in the saliva samples collected after the exams (p ≤ 0.05). This difference was confirmed by the automated electrophoresis system, particularly showing a reduction in cfDNA amounts in the 40-200 bp range with the reduction of stress (p ≤ 0.05). Conclusion: Psychosocial stress affects the release of cell-free DNA. This study reports that the amount of cfDNA found in saliva samples significantly changes in relation to stress. This preliminary study suggests that cfDNA in saliva samples could potentially serve as a biological marker for stress in healthy individuals.