# Forensic identification using airDNA: a preliminary study on the collection, isolation, amplification and sequencing of human DNA from air samples

## TL;DR

This study shows that human DNA can be collected from the air and used for forensic identification, especially through mitochondrial DNA sequencing.

## Contribution

The study demonstrates the feasibility of extracting and sequencing human mtDNA from air samples for forensic use.

## Key findings

- Human mtDNA can be successfully extracted and sequenced from air samples.
- Cotton filters provided better mtDNA sequencing results than glass fiber filters.
- Nuclear DNA recovery from air samples remains challenging.

## Abstract

Humans continuously release skin cells and DNA fragments into the air. This DNA can either remain airborne or settle onto surfaces as indoor dust. This study investigates the collection, isolation, amplification, and sequencing of human DNA from air samples, focusing on both nuclear and mitochondrial DNAs.

This study was conducted in a 15 m3 room and a meeting room, where air samples were systematically collected and filtered using a vacuum device equipped with various sterile filters. Rigorous protocols were implemented to prevent contamination throughout the process. Thirteen air samples were processed in this research, involving the participation of two females and two males.

The study demonstrated the feasibility of extracting and sequencing human mtDNA from air samples, while nuclear DNA quantification remained challenging. Notably, cotton filters yielded better mtDNA sequencing results compared to glass fiber filters. Despite limited nuclear DNA recovery, mtDNA sequencing was successful in several samples, providing interpretable DNA profiles.

This preliminary study highlights the potential use of airDNA in forensic investigations, emphasizing mtDNA sequencing as a viable approach when nuclear DNA is scarce. Future studies should prioritize mtDNA sequencing and consider using glass fiber or cotton filters for optimal airDNA collection.