A Comparison of Two Methods for the Recovery of Fingerprint DNA on Adhesive Tapes

Dual evidence processing is highly important to the forensic community to obtain as much probative information as possible from limited evidentiary samples. In this study, artificial and donor latent prints were deposited on adhesive substrates and developed by cyanoacrylate fuming. Two different kits, the One Touch™ DNA Rescue Adhesives Kit and the EZ1® Investigator DNA Kit, were used for DNA extraction. Both kits were assessed for their efficiency at obtaining sufficient DNA yield for successful short tandem repeat (STR) typing. Despite the individual challenges observed with each kit, both extraction methods resulted in DNA recovery with overall comparable DNA extract yield and partial to full STR profiles. However, the number of samples that yielded detectable amounts of DNA was significantly different between methods. The EZ1 method recovered DNA from all but one donor print (99% sample recovery) with an average percent STR allele recovery of 80% for all samples with detectable DNA. The One Touch method was unsuccessful in recovering DNA from 6 artificial and 14 donor print samples (72% sample recovery), but the percent STR recovery from all samples with detectable DNA was 96%. Further optimization could help improve the overall consistency of DNA recovery (One Touch kit) and percent STR recovery (EZ1 kit).