Comparison of Commercial Kits for Recovery and Analysis of Bacterial DNA From Fingerprints

Authors：Daniel M. Assenmacher M.S.; Stephen D. Fields Ph.D.; Scott S. Crupper Ph.D.

Source：Journal of Forensic Sciences, 2020, 65(4): 1310-1314.

DOI：10.1111/1556-4029.14280

• Microbiome
• Trace
• Fingerprints
• Next‐generation sequencing
• Bacterial DNA extraction
• DNA

In forensic science, fingerprints are a common source of evidentiary information. However, latent examination is not always successful and trace human DNA cannot always be obtained. Thus, examining the fingerprint microbiome may offer a suitable alternative to more traditional methods of forensic identification. The Zymo Research ZR Bacterial/Fungal DNA MicroPrep? Kit, Qiagen QIAmp? DNA Mini Kit, Promega Wizard? Genomic DNA Purification Kit, and the MPBio FastDNA? Spin Kit were compared for their ability to yield a sufficient amount of bacterial DNA for next‐generation sequencing in order to obtain a microbiome profile. Prints were deposited onto slides, allowed to sit for up to 1 month, and total DNA isolated and quantified using each kit. The kit from Zymo Research yielded the most concentrated DNA sample (0.0084 ng/μL) in the least amount of time as compared to other kits examined. Although this amount of DNA was far below the recommended DNA concentration threshold recommended for next‐generation sequencing, a microbiome profile was successfully obtained. As interest in using the microbiome of an individual as a forensic tool continues to increase, there is the possibility that the microbiome of a fingerprint could complement traditional human DNA profiling in the future. This study provides evidence that trace amounts of bacterial DNA from fingerprints is quantifiable and sufficient for microbiome analysis.