This two-phase forensic science study examined how much DNA individuals carry on their skin surface. The main goal for phase 1 was the development of a standardized method to test for human DNA shedding propensity. Shedding propensity is defined as how much DNA a person leaves behind when touching a surface. In phase 1 the research team collected skin surface samples and fingerprints from different locations for 30 volunteers on three different occasions.
The main goal of phase 2 was to use the sampling location established in phase 1 to determine the distribution of different levels of individual shedding propensity in 4 U.S. ethnic groups and correlate DNA shedding to biological characteristics of these test populations. Biological characteristics (e.g., sunburn or sweating propensity) were collected via a questionnaire or measured via dermatological probes (e.g., sebum and melanin content).