The use of tape lifts for DNA recovery is becoming increasingly common in forensic laboratories, however there is no consensus on the best type of tape to use or how it should be processed. The first goal of this study was to optimize the tape lift procedure. Six swabbing solutions, including adhesive removers, were used on eight types of tape to determine which solution and tape was most suited to recovering DNA. The swabbing procedure was also compared to soaking the tape in chloroform and soaking the tape in digestion buffer (1% SDS). Real Time PCR was used to quantify the amount of DNA recovered from each tape or recovery method. All types of tape were equally effective, and digestion buffer and water yielded more DNA than adhesive removers. Swabbing the tape with digestion buffer was more successful at recovering cells than soaking in chloroform, but no more effective than soaking in digestion buffer. The second goal of this study was to determine if tape lifts of the skin could serve as an alternative to buccal swabs for collecting reference samples. Based on preliminary results, three of seven body areas (behind the ear, the back of the hand, and the combination of the fingertips and between the fingers) were sampled on 20 volunteers using tape lifts and swabs. Short tandem repeat (STR) analysis revealed swabs to be more effective than tape lifts of the skin, and the region behind the ear to be a possible alternative source of reference DNA to buccal swabs.
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