Estimation of Personal Environment Via Fingertip Microbiome and Mobile Phone Surfaces

Fingerprints can serve to identify individuals, but fingerprint quality may be deteriorated, even to the point of eliminating fingerprints, due to the external environment.

Poor fingerprint quality cannot be effectively used to identify individuals; hence, the need for other methods.

We investigated the utility of bacterial communities and the only microorganisms present in the sample to identify internal and external factors in individuals. Samples included eight participants' fingerprints and their mobile phone surfaces. Bacterial DNA in the samples was sequenced using next-generation sequencing to target the V3-V4 region in the 16S ribosomal RNA gene. The QIIME program was used to perform a taxonomic assignment and alpha diversity and beta diversity analyses based on the sequence data.

Until now, personal identification has only relied on microbial communities. However, this study identified microbial differences according to Korean mobile phones, fingertips, or gender, and confirmed the possibility of characterization of samples when it was difficult to identify individuals by the microbial community. The biodiversity and composition of individual bacterial communities were affected by internal and external environments. Bacteria from individuals and mobile phones were shared due to contact between mobile phone surfaces and fingertips. Of the eight Koreans, six of the fingertips and mobile phone samples matched each other for personal identification.

This study confirmed that the bacteria from an individual could be matched with the contact object and could be used as forensic evidence. Such bacterial profiling of individuals may confer forensic evidence and serve as a basis for improving the accuracy of forensic verification.