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Bodnar SR, Smith C, Alsharji AA, Moroose T, Venter C, Iyengar A. DNA typing of cyanoacrylate fumed latent fingerprints using GlobalFiler™ and ForenSeq™ Signature Prep kits. J Forensic Sci 2024. [PMID: 38940006 DOI: 10.1111/1556-4029.15566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2024] [Revised: 05/17/2024] [Accepted: 06/03/2024] [Indexed: 06/29/2024]
Abstract
DNA typing of latent fingerprints is highly desirable to increase chances of individualization. We recovered DNA from Cyanoacrylate (CA) fumed fingerprints and used both GlobalFiler™ and ForenSeq™ DNA Signature Prep kits for DNA typing. For GlobalFiler™, samples were processed using a protocol modified for Low Template (LT)-DNA samples (half-volume reactions, 30 cycles) while for ForenSeq™ DNA Signature Prep, samples were processed using a standard protocol and fluorometer-based library quantitation. We evaluated genotyping success and quality of profiles in terms of completeness, Peak Height Ratio/Allele Coverage Ratio, presence of PCR artifacts and drop-in alleles. With GlobalFiler™, average autosomal STR (aSTR) profile completeness was 44.4% with 2-20 pg, 54.3% with 22-60 pg, and 95% with 64-250 pg DNA input. CODIS uploadable profiles were obtained in 2/10, 3/11, and 11/12 samples in these ranges. With ForenSeq™ DNA Signature Prep, average aSTR profile completeness was 19.7% with 1-20 pg and 45.2% with 22-47 pg but increased to 78.3% with 68-122 pg and 86.7% with 618-1000 pg DNA input. Uploadable profiles were obtained in 0/12, 4/11, 4/7, and 3/3 samples for these ranges. Results show very high sensitivity using both kits. Half-volume reactions and 30 cycles had minimal negative effect on Globalfiler™ profile quality, providing support for wider use after validation experiments to routinely improve results from LT samples. A standard protocol for the ForenSeq™ DNA Signature Prep kit was also highly successful with LT DNA obtained from CA-fumed fingerprints with additional information from isometric STR alleles and other markers.
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Affiliation(s)
- Sara R Bodnar
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, West Virginia, USA
| | - Coral Smith
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, West Virginia, USA
| | - Alekhlas A Alsharji
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, West Virginia, USA
| | - Tina Moroose
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, West Virginia, USA
| | - Casper Venter
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, West Virginia, USA
| | - Arati Iyengar
- Department of Forensic and Investigative Science, West Virginia University, Morgantown, West Virginia, USA
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He G, Wang W, Zhou Y, Zhao G, Liao J. Ampholytic ion-exchange magnetic beads: a promising tool for selecting short fragments in circulating cell-free DNA analysis. Front Oncol 2024; 14:1397680. [PMID: 38779084 PMCID: PMC11109406 DOI: 10.3389/fonc.2024.1397680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2024] [Accepted: 04/23/2024] [Indexed: 05/25/2024] Open
Abstract
Objective For liquid biopsy of cancer, the extraction of circulating cell-free DNA (cfDNA) from plasma is required. We evaluated the efficacy of use of magnetic submicron particles coated with abundant small zwitterions (MSP-ZEWBs) for extracting short fragments of cfDNA. Methods We developed and optimized an MSP-ZEWB-based cfDNA extraction method using ampholytic ion-exchange materials and compared its results with those using a control kit. We measured the cfDNA concentration by quantitative polymerase-chain-reaction and using the Qubit method and analyzed cfDNA fragmentation patterns using a bioanalyzer. Results The fragment size of cfDNA isolated from glycine hydrochloric acid at a pH of 2.2 exhibited a better alignment with the DNA marker. The highest DNA intensity was observed at the final concentration of 0.8% polyethylene glycol 8000. The intensity of cfDNA decreased significantly when isolated from plasma with DNA marker using MSP-ZEWBs with an adsorption buffer containing guanidine hydrochloride or isothiocyanoguanidine. All fragments were successfully extracted using MSP-ZEWBs from both plasma and phosphate-buffered saline. Notably, the intensity of short cfDNA fragments isolated using MSP-ZEWBs remained consistent for recovery of long DNA fragments. indicating a potential selective of small fragments. Conclusion The extraction of plasma cfDNA with MSP-ZEWBs requires no protein denaturation, shows resistance to cells remaining in plasma, and demonstrates higher overall efficiency and better reproducibility than other extraction methods. Use of MSP-ZEWBs may greatly enhance liquid biopsy of cancers through the analysis of plasma cfDNA in clinical practice.
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Affiliation(s)
- Gan He
- Gastrointestinal Surgery, Yongchuan Hospital of Chongqing Medical University, Chongqing, China
| | - Weixuan Wang
- Institute of Life Sciences, Chongqing Medical University, Chongqing, China
| | - Yongxia Zhou
- Department of Radiology, Yongchuan Hospital of Chongqing Medical University, Chongqing, China
- Center Laboratory, Yongchuan Hospital of Chongqing Medical University, Chongqing, China
| | - Guowei Zhao
- Gastrointestinal Surgery, Yongchuan Hospital of Chongqing Medical University, Chongqing, China
| | - Juan Liao
- Center Laboratory, Yongchuan Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Geriatric Disease Clinical Research Center, Chongqing, China
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Madden I, Taylor D, Mitchell N, Goray M, Henry J. Predicting probative levels of touch DNA on tapelifts using Diamond™ Nucleic Acid Dye. Forensic Sci Int Genet 2024; 70:103024. [PMID: 38335775 DOI: 10.1016/j.fsigen.2024.103024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 01/29/2024] [Accepted: 02/02/2024] [Indexed: 02/12/2024]
Abstract
Tapelifting is a common strategy to recover touch DNA deposits from porous exhibits in forensic DNA casework. However, it is known that only about 30 % of tapelifts submitted for DNA analysis in operational forensic laboratories yield profiles suitable for comparison or upload to a searchable database. A reliable means to identify and remove non-probative tapelifts from the workflow would reduce sample backlogs and provide significant cost savings. We investigated whether the amount of macroscopic or microscopic fluorescence on a tapelift following staining with Diamond Nucleic Acid Dye (DD), determined using a Polilight and Dino Lite microscope respectively, could predict the DNA yield and/or the DNA profiling outcome using controlled (saliva), semi-controlled (finger mark) and uncontrolled (clothing) samples. Both macroscopic and microscopic DD fluorescence could predict DNA yield and profiling outcome for all sample types, however the predictive power deteriorated as the samples became less controlled. For tapelifts of clothing, which are operationally relevant, Polilight fluorescence scores were significantly impacted by clothing fibres and other non-cellular debris and could not be used to identify non-probative samples. The presence of less than 500 cells on a clothing tapelift using microscopic counting of stained corneocytes was identified as a potential threshold for a non-probative DNA profiling outcome. A broader examination of the reliability of this threshold using a casework trial is recommended. Due to the labour intensiveness of microscopic cell counting, and the increased risk of inadvertent contamination, automation of this process using image software in conjunction with artificial neural networks (ANN) should be explored.
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Affiliation(s)
- Isla Madden
- College of Science and Engineering, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia
| | - Duncan Taylor
- College of Science and Engineering, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia; Forensic Science SA, GPO Box 2790, Adelaide, South Australia 5001, Australia
| | - Natasha Mitchell
- Forensic Science SA, GPO Box 2790, Adelaide, South Australia 5001, Australia
| | - Mariya Goray
- College of Science and Engineering, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia
| | - Julianne Henry
- College of Science and Engineering, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia; Forensic Science SA, GPO Box 2790, Adelaide, South Australia 5001, Australia.
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Bathrick AS, Norsworthy S, Plaza DT, McCormick MN, Slack D, Ramotowski RS. DNA recovery after sequential processing of latent fingerprints on black polyethylene plastic. J Forensic Sci 2024; 69:993-1001. [PMID: 38402545 DOI: 10.1111/1556-4029.15498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Revised: 02/12/2024] [Accepted: 02/12/2024] [Indexed: 02/26/2024]
Abstract
Latent fingerprints on plastic substrates can be visualized by using sequential treatments to enhance the contrast between the fingerprint residues and underlying substrate; however, the extent to which these processes affect subsequent DNA analysis is mostly unknown. Latent fingerprints deposited on black plastic by one donor were visualized with single-process fingerprint powders (i.e., white powder, bichromatic powder, or bichromatic magnetic powder) or sequential treatments (i.e., laser → reflected ultraviolet imaging system (RUVIS) → CA fuming → RUVIS → Rhodamine 6G, Ardrox, and MBD (RAM) or CA fuming → RAM/laser → bichromatic magnetic powder). Samples were examined after the addition of each treatment. DNA was collected using cotton swabs, extracted, quantified, and amplified. DNA yields, peak heights, number of alleles obtained, and percentage of DNA profiles eligible for CODIS upload were examined. Latent fingerprints processed with the laser and up to three sequential treatments generated DNA profiles with significantly higher peaks heights than those of the untreated samples. Fingerprints processed with the laser and up to two sequential treatments generated DNA profiles with significantly more alleles. All methods beginning with laser enhancement generated more CODIS-eligible profiles. Additional research is needed to determine the extent to which initial laser enhancement impacts the success of downstream DNA profiling results. Although DNA profile development is not guaranteed due to the variable quantities of DNA contained within latent fingerprints, the selection of an appropriate latent fingerprint visualization method could maximize both fingerprint detection and the generation of CODIS-eligible DNA profiles.
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Affiliation(s)
| | - Sarah Norsworthy
- Forensic Technology Center of Excellence, RTI International, Research Triangle Park, North Carolina, USA
| | | | - Mallory N McCormick
- Forensic Services Division, United States Secret Service, Washington, DC, USA
| | - Donia Slack
- Forensic Technology Center of Excellence, RTI International, Research Triangle Park, North Carolina, USA
| | - Robert S Ramotowski
- Forensic Services Division, United States Secret Service, Washington, DC, USA
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5
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Tuazon OM, Wickenheiser RA, Ansell R, Guerrini CJ, Zwenne GJ, Custers B. Law enforcement use of genetic genealogy databases in criminal investigations: Nomenclature, definition and scope. Forensic Sci Int Synerg 2024; 8:100460. [PMID: 38380276 PMCID: PMC10876674 DOI: 10.1016/j.fsisyn.2024.100460] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Revised: 02/07/2024] [Accepted: 02/07/2024] [Indexed: 02/22/2024]
Abstract
Although law enforcement use of commercial genetic genealogy databases has gained prominence since the arrest of the Golden State Killer in 2018, and it has been used in hundreds of cases in the United States and more recently in Europe and Australia, it does not have a standard nomenclature and scope. We analyzed the more common terms currently being used and propose a common nomenclature: investigative forensic genetic genealogy (iFGG). We define iFGG as the use by law enforcement of genetic genealogy combined with traditional genealogy to generate suspect investigational leads from forensic samples in criminal investigations. We describe iFGG as a proper subset of forensic genetic genealogy, that is, FGG as applied by law enforcement to criminal investigations; hence, investigative FGG or iFGG. We delineate its steps, compare and contrast it with other investigative techniques involving genetic evidence, and contextualize its use within criminal investigations. This characterization is a critical input to future studies regarding the legal status of iFGG and its implications on the right to genetic privacy.
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Affiliation(s)
- Oliver M. Tuazon
- Center for Law and Digital Technologies (eLaw), Institute for the Interdisciplinary Study of the Law, Leiden Law School, Leiden University, Kamerlingh Onnes Building, Steenschuur 25, 2311 ES, Leiden, the Netherlands
| | - Ray A. Wickenheiser
- New York State Police Crime Laboratory System, Forensic Investigation Center, 1220 Washington Avenue, Building #30, Albany, NY, 12226-3000, USA
| | - Ricky Ansell
- Swedish Police Authority, National Forensic Centre, SE-581 94, Linköping, Sweden
- Department of Physics, Chemistry and Biology, Linköping University, Sweden
| | - Christi J. Guerrini
- Baylor College of Medicine, Center for Medical Ethics and Health Policy, Houston, TX, 77030, USA
| | - Gerrit-Jan Zwenne
- Center for Law and Digital Technologies (eLaw), Institute for the Interdisciplinary Study of the Law, Leiden Law School, Leiden University, Kamerlingh Onnes Building, Steenschuur 25, 2311 ES, Leiden, the Netherlands
| | - Bart Custers
- Center for Law and Digital Technologies (eLaw), Institute for the Interdisciplinary Study of the Law, Leiden Law School, Leiden University, Kamerlingh Onnes Building, Steenschuur 25, 2311 ES, Leiden, the Netherlands
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Arsenault H, Nic Daeid N, Gray A. A synthetic fingerprint solution and its importance in DNA transfer, persistence and recovery studies. Forensic Sci Int Synerg 2023; 6:100330. [PMID: 37249970 PMCID: PMC10209804 DOI: 10.1016/j.fsisyn.2023.100330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 04/20/2023] [Accepted: 05/02/2023] [Indexed: 05/31/2023]
Abstract
A review of the literature on DNA transfer and persistence highlights many difficulties that are encountered when conducting research of this nature. One of the main problems highlighted repeatedly in the literature is the prevalence of inherent uncontrolled variation that accompany these studies, and in turn, the results obtained. This work aims to decrease the amount of intrinsic variability associated with DNA transfer and persistence experiments using a realistic proxy solution which is adaptable, of known composition, reproducible, and capable of being standardised. This proxy is composed of three parts: a synthetic fingerprint solution, cellular DNA, and cell free DNA. In this proof-of-concept study the proxy was tested with a small-scale DNA transfer and recovery experiment and the data obtained suggests that the use of a solution that mimics real fingerprint secretions, over an alternative (such as buffer or a body fluid), is important when working with non-donor provided trace DNA samples. This is because the DNA deposit solution likely impacts the transfer of DNA from fingers/hands to a surface as well as the ability to recover the biological material once deposited.
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Gray A, Kuffel A, Daeid NN. An improved rapid method for DNA recovery from cotton swabs. Forensic Sci Int Genet 2023; 64:102848. [PMID: 36821959 DOI: 10.1016/j.fsigen.2023.102848] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 12/13/2022] [Accepted: 02/14/2023] [Indexed: 02/17/2023]
Abstract
We present a novel rapid method for the recovery of cellular and free DNA from cotton swabs based on a simple elution buffer containing a high molecular weight polymer and detergent combined with a short proteinase K digestion to release cellular DNA. This method shows increased yields approaching 80% recovery of the input DNA compared to the QIAamp DNA Mini kit standard extraction protocol for swabs which has a recovery of 20-30%. The buffer components in the described method are compatible with direct PCR analysis of the isolated DNA without further purification. Recovery efficiencies were estimated by qPCR.
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Affiliation(s)
- Alexander Gray
- Leverhulme Research Centre for Forensic Science, University of Dundee, Dundee, UK.
| | - Agnieszka Kuffel
- Leverhulme Research Centre for Forensic Science, University of Dundee, Dundee, UK
| | - Niamh Nic Daeid
- Leverhulme Research Centre for Forensic Science, University of Dundee, Dundee, UK
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8
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DNA deposited in whole thumbprints: a reproducibility study. Forensic Sci Int Genet 2022; 58:102683. [DOI: 10.1016/j.fsigen.2022.102683] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 02/21/2022] [Accepted: 02/24/2022] [Indexed: 01/27/2023]
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9
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van Oorschot RAH, Meakin GE, Kokshoorn B, Goray M, Szkuta B. DNA Transfer in Forensic Science: Recent Progress towards Meeting Challenges. Genes (Basel) 2021; 12:genes12111766. [PMID: 34828372 PMCID: PMC8618004 DOI: 10.3390/genes12111766] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/04/2021] [Accepted: 11/04/2021] [Indexed: 01/16/2023] Open
Abstract
Understanding the factors that may impact the transfer, persistence, prevalence and recovery of DNA (DNA-TPPR), and the availability of data to assign probabilities to DNA quantities and profile types being obtained given particular scenarios and circumstances, is paramount when performing, and giving guidance on, evaluations of DNA findings given activity level propositions (activity level evaluations). In late 2018 and early 2019, three major reviews were published on aspects of DNA-TPPR, with each advocating the need for further research and other actions to support the conduct of DNA-related activity level evaluations. Here, we look at how challenges are being met, primarily by providing a synopsis of DNA-TPPR-related articles published since the conduct of these reviews and briefly exploring some of the actions taken by industry stakeholders towards addressing identified gaps. Much has been carried out in recent years, and efforts continue, to meet the challenges to continually improve the capacity of forensic experts to provide the guidance sought by the judiciary with respect to the transfer of DNA.
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Affiliation(s)
- Roland A. H. van Oorschot
- Office of the Chief Forensic Scientist, Victoria Police Forensic Services Department, Macleod, VIC 3085, Australia
- School of Molecular Sciences, La Trobe University, Bundoora, VIC 3086, Australia
- Correspondence:
| | - Georgina E. Meakin
- Centre for Forensic Science, University of Technology Sydney, Ultimo, NSW 2007, Australia;
- Centre for the Forensic Sciences, Department of Security and Crime Science, University College London, London WC1H 9EZ, UK
| | - Bas Kokshoorn
- Netherlands Forensic Institute, 2497 GB The Hague, The Netherlands;
- Faculty of Technology, Amsterdam University of Applied Sciences, 1097 DZ Amsterdam, The Netherlands
| | - Mariya Goray
- College of Science and Engineering, Flinders University, Adelaide, SA 5042, Australia;
| | - Bianca Szkuta
- School of Life and Environmental Sciences, Deakin University, Geelong, VIC 3220, Australia;
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Sijen T, Harbison S. On the Identification of Body Fluids and Tissues: A Crucial Link in the Investigation and Solution of Crime. Genes (Basel) 2021; 12:1728. [PMID: 34828334 PMCID: PMC8617621 DOI: 10.3390/genes12111728] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 10/26/2021] [Accepted: 10/26/2021] [Indexed: 12/13/2022] Open
Abstract
Body fluid and body tissue identification are important in forensic science as they can provide key evidence in a criminal investigation and may assist the court in reaching conclusions. Establishing a link between identifying the fluid or tissue and the DNA profile adds further weight to this evidence. Many forensic laboratories retain techniques for the identification of biological fluids that have been widely used for some time. More recently, many different biomarkers and technologies have been proposed for identification of body fluids and tissues of forensic relevance some of which are now used in forensic casework. Here, we summarize the role of body fluid/ tissue identification in the evaluation of forensic evidence, describe how such evidence is detected at the crime scene and in the laboratory, elaborate different technologies available to do this, and reflect real life experiences. We explain how, by including this information, crucial links can be made to aid in the investigation and solution of crime.
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Affiliation(s)
- Titia Sijen
- Division Human Biological Traces, Netherlands Forensic Institute, Laan van Ypenburg 6, 2497 GB The Hague, The Netherlands
- Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - SallyAnn Harbison
- Institute of Environmental Science and Research Limited, Private Bag 92021, Auckland 1142, New Zealand;
- Department of Statistics, University of Auckland, Private Bag 92019, Auckland 1142, New Zealand
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Cook R, Mitchell N, Henry J. Assessment of Diamond™ Nucleic Acid Dye for the identification and targeted sampling of latent DNA in operational casework. Forensic Sci Int Genet 2021; 55:102579. [PMID: 34455366 DOI: 10.1016/j.fsigen.2021.102579] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/04/2021] [Accepted: 08/15/2021] [Indexed: 12/19/2022]
Abstract
Recovery and DNA profiling of latent touch DNA deposits is a ubiquitous practice by operational forensic laboratories that provides critical evidence in many criminal investigations. Despite recent improvements in the sensitivity of contemporary DNA profiling kits, the inability to localise and visually quantify touch DNA deposits on an exhibit means that ineffective or unwarranted sampling is often performed leading to poor success. Diamond™ Nucleic Acid Dye (DD) is a fluorescent DNA binding dye which has recently been shown to bind to corneocytes enabling visualisation and targeted sampling of touch DNA deposits under controlled conditions. The ability to translate these findings to operational casework, where a diverse range of substrates is encountered and the amount and distribution of touch DNA is uncontrolled, is currently unknown. Here, we provide the first report on the use of DD in an operational context. Spraying items with DD was shown to have no impact on downstream immunological testing, DNA extraction, or DNA profiling with the GlobalFiler™ PCR amplification kit. DD was shown to effectively locate areas of touch DNA on select exhibits using the Polilight. Issues with background fluorescence, non-specific staining, interference from fingerprint enhancement reagents, or absorbance of the excitation light by black surfaces demonstrated that DD is not compatible with all exhibits. Background fluorescence also prevented the use of DD to screen for the presence of cellular material on IsoHelix swabs post-sampling but it was suitable for screening Lovell DNA tapelifts. A casework trial of 49 plastic bag and tape exhibits showed limited application of DD to triage out negative items as DNA was recovered from items where DD fluorescence was not detected. Where DD fluorescence was detected, its broad distribution prevented targeted sampling and any correlation to be made between the amount observed and DNA yield or profiling outcome. The DD procedure also increased the time taken to search exhibits and risk of inadvertent contamination. Our study suggests that DD is not suited as a generalised screening technique across all touch casework exhibits but further investigation is warranted to determine its applicability to specific exhibit types.
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Affiliation(s)
- Russell Cook
- Forensic Science SA, GPO Box 2790, Adelaide, South Australia 5001, Australia
| | - Natasha Mitchell
- Forensic Science SA, GPO Box 2790, Adelaide, South Australia 5001, Australia
| | - Julianne Henry
- Forensic Science SA, GPO Box 2790, Adelaide, South Australia 5001, Australia; College of Science and Engineering, Flinders University of South Australia, Bedford Park, South Australia 5042, Australia.
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Burrill J, Hotta R, Daniel B, Frascione N. Accumulation of endogenous and exogenous nucleic acids in "Touch DNA" components on hands. Electrophoresis 2021; 42:1594-1604. [PMID: 34080688 DOI: 10.1002/elps.202000371] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 05/07/2021] [Accepted: 05/20/2021] [Indexed: 02/03/2023]
Abstract
Successful forensic DNA profiling from handled items is increasingly routine in casework. This "touch DNA" is thought to contain both cellular and acellular nucleic acid sources. However, there is little clarity on the origins or characteristics of this material. The cellular component consists of anucleate, terminally differentiated corneocytes (assumed to lack DNA), and the occasional nucleated cell. The acellular DNA source is fragmentary, presumably cell breakdown products. This study examines the relative contributions each component makes to the hand-secretions (endogenous) and hand-accumulations (exogenous) by recovering rinses from the inside and outside of worn gloves. Additionally, cellular and acellular DNA was measured at timepoints up to 2 h after hand washing, both with and without interim contact. Microscopic examination confirmed cell morphology and presence of nucleic acids. Following the novel application of a hair keratinocyte lysis method and plasma-DNA fragment purification to hand rinse samples, DNA profiles were generated from both fractions. Exogenous cell-free DNA is shown to be a significant source of touch DNA, which reaccumulates quickly, although its amplifiable nuclear alleles are limited. Endogenous DNA is mostly cellular in origin and provides more allelic information consistently over time.
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Affiliation(s)
- Julia Burrill
- King's Forensics, Department of Analytical, Environmental & Forensic Sciences, School of Population Health & Environmental Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Rachel Hotta
- King's Forensics, Department of Analytical, Environmental & Forensic Sciences, School of Population Health & Environmental Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Barbara Daniel
- King's Forensics, Department of Analytical, Environmental & Forensic Sciences, School of Population Health & Environmental Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
| | - Nunzianda Frascione
- King's Forensics, Department of Analytical, Environmental & Forensic Sciences, School of Population Health & Environmental Sciences, Faculty of Life Sciences and Medicine, King's College London, London, UK
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