OPUS Collection:

DNA recovery from 3D printed firearms

2026-03-01T00:00:00Z

Title: DNA recovery from 3D printed firearms Authors: Oltrogger, FT; Howe, G; McNevin, D; Bolton, M; O’Driscoll, C; Woodcock, S Abstract: Over the last few years, additive manufacturing, by means of fused deposition modelling 3D printing, has become increasingly popular and accessible due to the relative low costs, flexibility, and continually lowering barriers for entry. Unfortunately, while this technology is not only used by hobbyists for creative or practical creation of custom objects using a variety of thermoplastic materials, they can also be used in the manufacture of firearms. From fully printed to hybrid designs, AM/3D printing has been used to produce parts for fully functional firearms capable of discharging conventional ammunition. The designs for such firearms can be easily found, downloaded and shared from the internet with 'enthusiasts' developing ever more sophisticated designs. In environments where lawful possession of firearms is strongly controlled, the ability to manufacture and assemble firearms through 3D printing technologies presents an increasing challenge for law enforcement, especially for forensic units tasked with collection, examination and recovery of evidence from these items. Forensic examination of 3D printed firearms can require a different approach compared to conventional firearms if maximum forensic intelligence is desired. Due to the decentralised and often individual nature of manufacture, biometric identification of both the handler/possessor and the manufacturer/assembler of the firearm can have investigative value. However, this can present a dilemma, as collection of biometric evidence from internal surfaces of the firearm typically requires dismantling of components which may affect functionality in subsequent test firing processes. This study aims to investigate DNA transfer and recovery on 3D printed firearms (Harlot pistols and FGC-9) in casework-inspired handling scenarios, to determine the most probative regions for the recovery of DNA originating from the assembler and handler of such firearms as well as determining the effect of firing (or test-firing) the firearm. The findings suggest that assembler DNA can be recovered from internal surfaces of the firearms, with significantly more DNA recovered from internal grip pieces than internal triggers. Further, the proportions of assembler DNA recovered on internal surfaces were significantly more than the proportions on external surfaces, based on contributor proportion percentages. In this study, test firing of the firearm, even up to 25 times, did not result in detectable DNA relocation onto internal surfaces from the individual conducting the test fires.

DNA transfer and recovery on 3D printed firearms

2026-03-16T00:00:00Z

Title: DNA transfer and recovery on 3D printed firearms Authors: Oltrogger, F; Kidd-Smith, A; Howe, G; Meakin, G; McNevin, D; Bolton, M; O’Driscoll, C

Comparison of Algorithms for Kinship Inference Using the Verogen ForenSeq® Kintelligence Kit.

2026-03-23T00:00:00Z

Title: Comparison of Algorithms for Kinship Inference Using the Verogen ForenSeq® Kintelligence Kit. Authors: Di Scala, C; Grisedale, K; Ward, J; McNevin, D Abstract: BACKGROUND/OBJECTIVES: Forensic kinship analysis is a rapidly developing practice that uses genetic data to identify unknown persons of interest through their genetic relatives. It can be used to generate new leads in forensic investigations, especially those involving long-term missing persons and unidentified human remains. More recently, the advent of SNP profiling panels designed specifically for forensic use has led to the exploration of kinship analysis using medium-density SNP data. This study aimed to evaluate the extent to which genetic relationships could be inferred using such data, and to assess the performance of different kinship inference methods. METHODS: Kinship analysis was performed with both real and simulated profiles using the panel of SNPs contained within the Verogen ForenSeq® Kintelligence Kit, with a wide range of relationship types and seven types of kinship inference methods. RESULTS: It was determined that kinship inferences were possible out to the fourth degree of kinship, and all inference methods analysed were equally effective when tested using simulated data. However, some variation between methods was observed when they were analysed using real sample data, suggesting that further study is needed using a larger sample size. CONCLUSIONS: The results of this study demonstrate that medium-density SNP data is sufficient for extended kinship inference out to the fourth degree, and that several kinship inference methods are suitable for use with the Verogen ForenSeq® Kintelligence Kit. These findings will support its application in forensic investigations involving the inference of distant genetic relationships.

Analytical investigation of metal distribution from e-cigarette aerosols to lung deposition using multi-platform mass spectrometry

Title: Analytical investigation of metal distribution from e-cigarette aerosols to lung deposition using multi-platform mass spectrometry Authors: McGrath, J; Royle, O; Thorpe, A; McCauley, JI; Ueland, M; Kabakova, I; Chen, H; Clases, D; Oliver, BG; Bordin, DM Abstract: Abstract E-cigarettes are promoted as a safer alternative to conventional tobacco, yet emerging evidence indicates they may expose users to harmful metals. While prior research has focused on nicotine and organic constituents, the bioaccumulation and spatial distribution of toxic metals in lung tissue remain poorly understood. In this study, a multi-platform analytical approach combining ICP-MS, GC-ICP-MS, GC-MS, and LA-ICP-MS/MS was employed to characterise the elemental and organic composition of refillable e-cigarette liquid and its corresponding aerosol, and to assess metal accumulation in murine lung tissue following short-term exposure. Balb/c mice (7 weeks, n = 8 per group) were exposed to nicotine-containing e-cigarette aerosols (8, 16, or 32 puffs; 30 min, twice daily for 4 days) or ambient air (control). Results showed that multiple toxic metals and organometallic species were detected in both e-liquid and aerosol, including species of Al, Ni, Cu, As, Br, Sn, and Hg. Elemental bioimaging of murine lungs found heterogeneous focal accumulation patterns in lung tissue, with increased Cu, significantly elevated Ni and Pb, and significantly reduced pulmonary Fe concentrations ( p ≤ 0.005). Metal distribution patterns were exposure-related but not strictly dose-dependent, indicating a complex deposition and clearance mechanism. This study provides the first evidence of metal-containing (organometallic) species in e-cigarette aerosols and exposure-associated metal accumulation in murine lung tissue. These findings reinforce the need for further mechanistic and longitudinal investigations to assess the health risks associated with chronic vaping exposure. Graphical abstract