Simply Forensic Reference Library
Touch DNA
Forensic DNA & Genetics
Definition. DNA recovered from a surface or object after contact, which can originate from skin-associated cells or other transferred biological material.
How the term is used
Deposition, persistence, substrate, recovery method and background DNA affect the result.
Forensic example
A handled phone yields an STR profile from its outer surface.
Interpretation limitation
The profile does not alone prove direct touch, last contact or timing.
References and further reading
SWGDAM guidelines for forensic DNA analysis. The explanation and example are original educational summaries; consult the cited material and current laboratory guidance for authoritative application.