The application of the skin virome for human identification

The use of skin virome offers a unique approach for human identification purposes in instances where a viable and statistically relevant human DNA profile is unavailable. The skin virome may act as an alternative DNA profile and/or an additional form of probative genetic material. To date, no study has attempted to investigate the human virome over a time series across various physical locations of the body to identify its diagnostic potential as a tool for human identification. For this study, we set out to evaluate the stability, diversity, and individualization of the human skin virome. An additional goal was to identify putative viral signatures that can be used in conjunction with traditional forensic STR loci. In order to accomplish this, human viral metagenomes were collected and sequenced from 42 individuals at three anatomical locations (left hand, right hand, and scalp) across multiple collection periods over a 6-month window of time. Assembly dependent and independent bioinformatic approaches, along with a database centered assessment of viral identification, resulted in three sets of stable putative viral markers. In total, with the three sets combined, we identified 59 viral biomarker regions, consisting of viral species and uncharacterized viral genome assemblies, that were stable over the sampling period. Additionally, we found the abundance profiles of these 59 viral biomarkers, based on presence or absence, to be significantly different across subjects (P < 0.001). Here we demonstrate that not only is the human virome applicable to be used for human identification, but we have identified many viral signatures that can putatively be used for forensic applications, thus providing a foundation to the novel field of forensic virology.