RESUMO
The heightened sensitivity of DNA typing techniques, paired with the extensive use of trace DNA in forensic investigations, has resulted in an increased need to understand how and when DNA is deposited on surfaces of interest. This study focussed on the transfer, persistence, and prevalence of trace DNA in a single occupation of an office space by an intruder, when all contacts made during occupation and for the two hours prior and post occupation were known. The extent to which DNA could be recovered from contacted/not contacted surfaces was investigated. This study investigates the impacts of these movements and use of an office space when the duration of occupancy, surface contact histories and shedder status of participants are known. Contacts were documented and surfaces in the office space were targeted for sampling. Categories were set for target sampling that included different types of contact. Direct and indirect DNA transfer was detected in 55â¯% and 6â¯% of samples, respectively. Contactless DNA transfer was detected in 0.5â¯% of samples. The owner was observed as the sole/major/majority contributor in 77â¯% of the samples and as minor contributor in 10â¯% of samples. The intruder was observed as the sole/major/majority contributor in 14â¯% of samples and as the minor contributor in 16â¯%. An increased number of contacts increased the relative DNA contribution of the individual making the contact, however, not all observed direct contacts resulted in detectable DNA transfer. The outcome of this study will aid in better sample targeting strategies and contribute to the pool of data assisting in the development of activity level assessments.
Assuntos
Impressões Digitais de DNA , DNA , Humanos , DNA/genética , TatoRESUMO
One of the most challenging issues still present in forensic DNA analysis is identifying individuals in samples containing DNA from multiple contributors. The introduction of novel identification markers may be a useful tool in the deconvolution of such DNA mixtures. In this study, we investigated the potential of alleles from the human leukocyte antigen system (HLA) to aid in identifying individuals in complex, multiple-donor DNA samples. The most advantageous characteristic of the HLA complex is its polymorphism in the human genome. A 22-loci multiplex with HLA markers was designed and applied to two-, three-, and four-person DNA mixtures. The results of the conducted experiments demonstrated that the identification of individuals in multiple contributor samples with the help of HLA markers is possible; however, it is clear that the reliability of the method is heavily dependent on the number of unique alleles for each individual in the analysed mixture. In order to compare this novel approach against the already established process, the same group of reference and multiple-contributor samples was analysed with a commonly used set of STR markers. This proof-of-concept research shows the importance of examining alternative solutions to the current deconvolution challenge in forensic DNA profiling.
Assuntos
Alelos , Impressões Digitais de DNA , DNA , Antígenos HLA , Estudo de Prova de Conceito , Humanos , Antígenos HLA/genética , Impressões Digitais de DNA/métodos , DNA/genética , Marcadores Genéticos , Repetições de MicrossatélitesRESUMO
Y chromosome short tandem repeats (Y-STRs) typing is a useful tool in scenarios such as mass graves analysis or disaster victim identification and has become a routine analysis in many laboratories. Not many comparisons have been performed with the currently available commercial kits, much less with degraded skeletal remains. This research aims to evaluate the performance of three commercial Y-STR kits: Yfiler™ Plus, PowerPlex® Y23, and Investigator® Argus Y-28 in 63 degraded skeletal remains from mass graves. PowerPlex® Y23 yields more reportable markers and twice the RFU on average, while Yfiler™ Plus and Investigator® Argus Y-28 exhibited a similar behaviour. Additionally, Argus Y-28, which has not been tested with this kind of samples in literature before, showed a good performance. Finally, a predictive model was attempted to be developed from quantification and autosomal STR data. However, no acceptable model could be obtained. Nevertheless, good Y-STR typing results may be expected if at least 50 pg DNA input is used or 13 autosomal markers were previously obtained.
Assuntos
Restos Mortais , Cromossomos Humanos Y , Impressões Digitais de DNA , Repetições de Microssatélites , Humanos , Impressões Digitais de DNA/métodos , Masculino , Reação em Cadeia da Polimerase , Degradação Necrótica do DNA , Osso e Ossos/químicaRESUMO
The introduction of PCR into forensic science and the rapid increases in the sensitivity, specificity and discrimination power of DNA profiling that followed have been fundamental in shaping the field of forensic biology. Despite these developments, the challenges associated with the DNA profiling of trace, inhibited and degraded samples remain. Thus, any improvement to the performance of sub-optimal samples in DNA profiling would be of great value to the forensic community. The potential exists to optimise the PCR performance of samples by altering the cycling conditions used. If the effects of changing cycling conditions upon the quality of a DNA profile can be well understood, then the PCR process can be manipulated to achieve a specific goal. This work is a proof-of-concept study for the development of a smart PCR system, the theoretical foundations of which are outlined in part 1 of this publication. The first steps needed to demonstrate the performance of our smart PCR goal involved the manual alteration of cycling conditions and assessment of the DNA profiles produced. In this study, the timing and temperature of the denaturation and annealing stages of the PCR were manually altered to achieve the goal of reducing PCR runtime while maintaining an acceptable quality and quantity of DNA product. A real-time feedback system was also trialled using an STR PCR and qPCR reaction mix, and the DNA profiles generated were compared to profiles produced using the standard STR PCR kits. The aim of this work was to leverage machine learning to enable real-time adjustments during a PCR, allowing optimisation of cycling conditions towards predefined user goals. A set of parameters was found that yielded similar results to the standard endpoint PCR methodology but was completed 30 min faster. The development of an intelligent system would have significant implications for the various biological disciplines that are reliant on PCR technology.
Assuntos
Aprendizado de Máquina , Reação em Cadeia da Polimerase , Humanos , Reação em Cadeia da Polimerase/métodos , Impressões Digitais de DNA/métodos , DNA/genética , Genética Forense/métodosRESUMO
The multifaceted, multivendor-based global design supply chain induces hardware threats of intellectual property (IP) piracy for modern computing and electronic systems. Current hardware watermarking techniques fall short either in terms of watermark strength (size of covert constraints generated) or number of security layers/variables involved in the security constraints generation process. This paper presents a novel approach for high level synthesis (HLS) watermarking by bio-mimicking DNA fingerprint profiling to counter hardware IP piracy. The proposed approach effectively captures the vital DNA fingerprint profiling phases such as DNA sequencing, DNA fragmentation, fragment replication, DNA ligase, etc. and bio-mimics them to generate a digital watermarking framework. The presented approach has been demonstrated on convolutional layer and JPEG compression-decompression (CODEC) algorithms that are widely used in several medical and machine learning applications. The proposed approach has been thoroughly compared with several state-of-the-art approaches. The proposed approach depicts superior security in the probability of coincidence of up to ~ 104 and tamper tolerance of up to ~ 10368 at 0% overhead as compared to the prior approaches.
Assuntos
Algoritmos , Segurança Computacional , Impressões Digitais de DNA , Impressões Digitais de DNA/métodos , Humanos , Computadores , DNARESUMO
Zanthoxylum is a versatile economic tree species utilized for its spice, seasoning, oil, medicinal, and industrial raw material applications, and it has a lengthy history of cultivation and domestication in China. This has led to the development of numerous cultivars. However, the phenomenon of mixed cultivars and confusing names has significantly obstructed the effective utilization of Zanthoxylum resources and industrial development. Consequently, conducting genetic diversity studies and cultivar identification on Zanthoxylum are crucial. This research analyzed the genetic traits of 80 Zanthoxylum cultivars using simple sequence repeat (SSR) and inter-Primer Binding Site (iPBS) molecular markers, leading to the creation of a DNA fingerprint. This study identified 206 and 127 alleles with 32 SSR markers and 10 iPBS markers, respectively, yielding an average of 6.4 and 12.7 alleles (Na) per marker. The average polymorphism information content (PIC) for the SSR and iPBS markers was 0.710 and 0.281, respectively. The genetic similarity coefficients for the 80 Zanthoxylum accessions ranged from 0.0947 to 0.9868 and from 0.2206 to 1.0000, with mean values of 0.3864 and 0.5215, respectively, indicating substantial genetic diversity. Cluster analysis, corroborated by principal coordinate analysis (PCoA), categorized these accessions into three primary groups. Analysis of the genetic differentiation among the three Zanthoxylum (Z. bungeanum, Z. armatum, and Z. piperitum) populations using SSR markers revealed a mean genetic differentiation coefficient (Fst) of 0.335 and a gene flow (Nm) of 0.629, suggesting significant genetic divergence among the populations. Molecular variance analysis (AMOVA) indicated that 65% of the genetic variation occurred within individuals, while 35% occurred among populations. Bayesian model-based analysis of population genetic structure divided all materials into two groups. The combined PI and PIsibs value of the 32 SSR markers were 4.265 × 10- 27 and 1.282 × 10- 11, respectively, showing strong fingerprinting power. DNA fingerprints of the 80 cultivars were established using eight pairs of SSR primers, each assigned a unique numerical code. In summary, while both markers were effective at assessing the genetic diversity and relationships of Zanthoxylum species, SSR markers demonstrated superior polymorphism and cultivar discrimination compared to iPBS markers. These findings offer a scientific foundation for the conservation and sustainable use of Zanthoxylum species.
Assuntos
Impressões Digitais de DNA , Variação Genética , Repetições de Microssatélites , Zanthoxylum , Zanthoxylum/genética , Repetições de Microssatélites/genética , Marcadores Genéticos , Filogenia , DNA de Plantas/genética , Polimorfismo Genético , Alelos , Sítios de LigaçãoRESUMO
Mitochondrial DNA (mtDNA) is an important genetic marker for degraded biological sample identification, maternal pedigree tracing, and population genetic structure study owing to its characteristics of high copy number, anti-degradable ring structure, and maternal inheritance. Whole mtDNA genome sequencing is an optimal method for the analysis of mtDNA polymorphism and heterogeneity because it allows for the comprehensive use of maternal genetic information. However, because of lacking quantitative evaluations for sequencing data, the scientific interpretation standards for mtDNA sequencing results of the previously used sequencing systems are often different, and false positive or false negative results are prone to occur when faced with the interference of nuclear genomic DNA, or the heterogeneities of mtDNA sequence and structure. In this study, we evaluated a novel mtDNA whole genome sequencing system using long fragment amplification strategy on the DNA nanoball (DNB) sequencing platform. This system demonstrated high sequencing quality and specific mtDNA sequencing efficiencies on positive control DNA and FTA bloodstain samples, as the average Q20 and Q30 values of the corresponding samples were 97.17â¯% and 91.93â¯%; 97.37â¯% and 92.48â¯%, respectively. The mean mapping percentages for the reference sequences of whole genome DNA (wgDNA), mtDNA, and nuclear genomic DNA (ngDNA) in the corresponding samples were 99.98â¯%, 99.97â¯%, 0.03â¯%, and 99.91â¯%, 99.40â¯%, 0.60â¯%; respectively. The average error calling rates for the bases A, C, G, and T of the whole mtDNA genome were 0.2519â¯%, 0.2550â¯%, 0.2906â¯%; and 0.2392â¯%, respectively. The efficacy of heteroplasmy identification was assessed using a set of theoretical sites with predetermined rates. These sites were created by combining the samples with known mtDNA haplotypes in certain proportions. The absolute errors between observed and theoretical heteroplasmy values were 89.59â¯%, 74.68â¯%, 50.20â¯%, 12.65â¯%, 8.31â¯%, and 4.85â¯%, while the theoretical heteroplasmy values were 5â¯%, 10â¯%, 20â¯%, 80â¯%, 90â¯%, and 95â¯%, respectively. The absolute error exhibited relative stability when the mtDNA sequencing depth exceeded 500×. Furthermore, the system sequencing efficiency was also confirmed among different kinds of samples, and these samples included natural samples (e.g., peripheral blood samples preserved on FTA cards for 2 and 11 years, and on filter paper for 6 and 9 years), degraded samples, sensitivity samples, samples derived from various bodily fluids, and maternal pedigree samples. In summary, the whole mtDNA genome sequencing system used for forensic identification demonstrated high performance in analyzing mtDNA sequence information, and showed significant prospects for forensic application and maternal genetic research.
Assuntos
DNA Mitocondrial , Sequenciamento Completo do Genoma , DNA Mitocondrial/genética , Humanos , Genética Forense/métodos , Manchas de Sangue , Análise de Sequência de DNA , Técnicas de Amplificação de Ácido Nucleico , Reação em Cadeia da Polimerase , Genoma Mitocondrial , Impressões Digitais de DNARESUMO
The validity of a probabilistic genotyping (PG) system is typically demonstrated by following international guidelines for the developmental and internal validation of PG software. These guidelines mainly focus on discriminatory power. Very few studies have reported with metrics that depend on calibration of likelihood ratio (LR) systems. In this study, discriminatory power as well as various calibration metrics, such as Empirical Cross-Entropy (ECE) plots, pool adjacent violator (PAV) plots, log likelihood ratio cost (Cllr and Cllrcal), fiducial calibration discrepancy plots, and Turing' expectation were examined using the publicly-available PROVEDIt dataset. The aim was to gain deeper insight into the performance of a variety of PG software in the 'lower' LR ranges (â¼LR 1-10,000), with focus on DNAStatistX and EuroForMix which use maximum likelihood estimation (MLE). This may be a driving force for the end users to reconsider current LR thresholds for reporting. In previous studies, overstated 'low' LRs were observed for these PG software. However, applying (arbitrarily) high LR thresholds for reporting wastes relevant evidential value. This study demonstrates, based on calibration performance, that previously reported LR thresholds can be lowered or even discarded. Considering LRs >1, there was no evidence for miscalibration performance above LR â¼1000 when using Fst 0.01. Below this LR value, miscalibration was observed. Calibration performance generally improved with the use of Fst 0.03, but the extent of this was dependent on the dataset: results ranged from miscalibration up to LR â¼100 to no evidence of miscalibration alike PG software using different methods to model peak height, HMC and STRmix. This study demonstrates that practitioners using MLE-based models should be careful when low LR ranges are reported, though applying arbitrarily high LR thresholds is discouraged. This study also highlights various calibration metrics that are useful in understanding the performance of a PG system.
Assuntos
Impressões Digitais de DNA , Software , Humanos , Funções Verossimilhança , Calibragem , Genótipo , DNA/genética , DNA/análise , Repetições de MicrossatélitesRESUMO
Forensic Biology is contingent upon matching DNA profiles between a crime sample and a reference sample. There are several capillary electrophoresis kits available to generate a short tandem repeat (STR) profile from DNA samples, while newer methods using massively parallel sequencing are slowly being implemented in forensic laboratories worldwide. During evaluation of a newer capillary electrophoresis kit, Applied Biosystems™ VeriFiler™ Plus, a discordance was observed in the Penta D locus. The previous kit, Promega PowerPlex 21® System produced a 13.4,14 genotype, whilst VeriFiler™ Plus produced a 14,14 genotype. An expanded investigation into Penta D microvariant alleles revealed that multiple discordances were observed for DNA profiles containing larger x.4 variants. There was full concordance between PowerPlex® 21 and QIAGEN Investigator® 26plex, however discordances were observed between VeriFiler™ Plus and the other three kits tested, including the massively parallel sequencing kit, Verogen ForenSeq® MainstAY. Notably, four of these discordances resulted in null alleles with the VeriFiler™ Plus kit. A review of the Penta D DNA sequences in MainstAY revealed fully concordant microvariant alleles involved deletions within the repeat region, whilst variability in the discordances observed were dependent on the location of the variation outside the repeat region and the analysis method used. Variations observed within the 5' flanking region produced the same allele designation across all capillary electrophoresis kits. However, deletions within the 3' region either produced a null allele for VeriFiler™ Plus where the deletion is thought to overlap the primer binding site, or microvariant alleles for the PowerPlex® 21 and Investigator 26plex kits, which produced longer Penta D amplicons. The discovery of these variations in the Penta D flanking sequences is informative as it increases the awareness of Penta D discordances between different kit chemistries in nominated reference DNA profile comparisons and DNA database searching and matching alike, and provides support for this phenomenon when providing evidence as to the admissibility of such results in trial proceedings.
Assuntos
Alelos , Impressões Digitais de DNA , Eletroforese Capilar , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites , Humanos , Cromossomos Humanos X , Análise de Sequência de DNA , GenótipoRESUMO
The sensitivity of DNA analysis has progressed to the point that trace levels of DNA, originating from only a few cells, can generate informative profiles. This means that virtually any item or surface can be sampled with a reasonable chance of obtaining a DNA profile. As the presence of DNA does not suggest how it was deposited, questions are often raised as to how the DNA came to be at a particular location and the activity that led to its deposition. Therefore, understanding different modes of DNA deposition, reflective of realistic forensic casework situations, is critical for proper evaluation of DNA results in court. This study aimed to follow the movements of DNA to and from individuals and common household surfaces in a residential premises, while socially interacting. This took place over an hour and involved four participants, with known shedder status, designated as visitors (a male and a female) and hosts (a male and a female), who engaged in the activity of playing a board game while being served food. During the study, the participants were instructed to use the toilet on a single occasion to assess the transfer of DNA to new and unused underwear that was provided. All contacts made by the participants in the dining room and kitchen were video recorded to follow the movements of DNA. Samples were collected based on the history of contact, which included hands, fingernails and penile swabs. Direct contacts resulted in detectable transfer (LR > 1) in 87â¯% (87/100) of the non-intimate samples and clothing. For surfaces touched by multiple participants, DNA from the person who made the last contact was not always detectable. The duration and number of contacts did not significantly affect the detection of the person contacting the item. On the other hand, presence of background DNA and participant's shedder status appear to play an important role. Further, unknown contributors were detected in the majority of samples. Finally, indirect transfer was observed on a number of occasions including co-habiting partners of guests who were not present at the study location. The results of this study may assist with decision making for exhibit selection or targeting areas for sampling within the home environment. Our findings can also be used in conjunction with previous literature to develop activity-level evaluations in such situations where the source of the DNA is conceded, but the mode of deposition is disputed.
Assuntos
Impressões Digitais de DNA , DNA , Tato , Humanos , DNA/genética , DNA/análise , Feminino , MasculinoRESUMO
Since 1995, national forensic DNA databases have used a maximum number of contributors, and a minimum number of loci to reduce the risk of providing false leads. DNA profiles of biological traces that do not meet these criteria cannot be loaded into these databases. In 2023, about 10â¯% of more than 15,000 trace DNA profiles analyzed in western Switzerland were not compared at the national level, even though they were considered to be interpretable, mainly because they contained the DNA from more than two persons. In this situation, police services can request local comparisons with DNA profiles of known persons and/or with other traces, but this occurs in only a small proportion of cases, so that DNA mixtures are rarely used to help detect potential series. The development of probabilistic genotyping software and its associated tools have made possible the efficient performance of this type of comparison, which is based on likelihood ratios (LR) rather than on the number of shared alleles. To highlight potential common contributors for investigation and intelligence purposes, the present study used the mixture-to-mixture tool of the software STRmix v2.7 to compare 235 DNA profiles that cannot be searched the Swiss DNA database. These DNA profiles originated from traces collected by six different police services in 2021 and 2022. Traces were selected by the police based on information that indicated that they were from potential series. Associations between profiles were compared with expected investigative associations to define the value of this approach. Among the 27,495 pairwise comparisons of DNA profiles, 88 pairs (0.3â¯%) showed at least one potential common contributor when using a LR threshold of 1000. Of these 88 pairs, 60 (68.2â¯%) were qualified by the police services as "expected" (60/88), 22 (25.0â¯%) as "possible", and six (6.8â¯%) as "unexpected". Although it is important to consider the limits of this approach (e.g., adventitious or missed associations, cost/benefit evaluation, integration of DNA mixture comparison in the process), these findings indicate that non CODIS loadable DNA mixtures could provide police agencies with information concerning potential series at both the local and national level.
Assuntos
Impressões Digitais de DNA , DNA , Bases de Dados de Ácidos Nucleicos , Repetições de Microssatélites , Software , Humanos , Suíça , DNA/genética , Funções Verossimilhança , Genótipo , PolíciaRESUMO
According to the principle of Locard "Every contact leaves a trace", when touching a surface, a bi-directional transfer of self and non-self-DNA residing on the hands and touched objects can occur. Metals are commonly encountered in forensic evidence and, during hand contact with these surfaces, a transfer of metal particles could occur together with the transfer of human DNA. This study proposes a proof-concept approach for the original detection of metal particles and touch DNA to track the activity performed by a donor and particularly to assess the metallic substrate touched before the contact with a subsequent surface. To this scope, a scenario of contact events was simulated by three volunteers, who participated in fingerprint deposition firstly on copper and then on plastic and glass surfaces. Twenty-four stubs were collected on the hands of volunteers and the secondary surfaces and then analyzed by environmental scanning electron microscopy (ESEM). DNA was quantified only from copper and plastic surfaces. Ten additional volunteers followed the same protocol of deposition on copper and then on plastic surfaces to evaluate DNA transfer only. On 20 touch DNA samples, the copper surface yielded significantly lower DNA amounts, ranging from 0.001 to 0.129â¯ng/µl, compared to the secondary touched plastic surface, ranging from 0.007 to 0.362â¯ng/µl. ESEM-EDS analysis showed that copper particles could be abundantly detected on the hands of the volunteers after contact with the copper surface. Particles containing silicates with copper were shown on plastic, while they were only found in 1/3 of samples on glass. Our proof-of-concept study has shown that ESEM-EDS analysis has the potential to detect copper particles transferred to the hands of volunteers during contact with a copper metallic surface and deposited on secondarily touched items. The results suggest that this original ESEM-DNA parallel approach could potentially allow the tracking of DNA transfer and metal particles at a crime scene, although this represents only a first step and further research on a wider casuistry could help to address the interpretation of results given activity level propositions.
Assuntos
Cobre , Impressões Digitais de DNA , DNA , Microscopia Eletrônica de Varredura , Tato , Humanos , DNA/análise , Estudo de Prova de Conceito , Vidro , Plásticos , Metais , MãosRESUMO
This study evaluates the performance of analysing surface DNA samples using massively parallel sequencing (MPS) compared to traditional capillary electrophoresis (CE). A total of 30 samples were collected from various surfaces in an office environment and were analysed with CE and MPS. These were compared against 60 reference samples (office inhabitants). To identify contributors, likelihood ratios (LRs) were calculated for MPS and CE data using the probabilistic genotyping software MPSproto and EuroForMix respectively. Although a higher number of sequences/peaks were observed per DNA profile in MPS compared to CE, LR values were found to be lower for MPS data formats. This might be the result of the increased complexity of MPS data, along with a possible elevation of unknown alleles and/or artefacts. The study highlights avenues for improving MPS data quality and analysis to facilitate more robust interpretation of challenging casework-like samples.
Assuntos
Impressões Digitais de DNA , DNA , Eletroforese Capilar , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Funções Verossimilhança , DNA/genética , DNA/análise , Análise de Sequência de DNARESUMO
Considering activity level propositions in the evaluation of forensic biology findings is becoming more common place. There are increasing numbers of publications demonstrating different transfer mechanisms that can occur under a variety of circumstances. Some of these publications have shown the possibility of DNA transfer from site to site on an exhibit, for instance as a result of packaging and transport. If such a possibility exists, and the case circumstances are such that the area on an exhibit where DNA is present or absent is an observation that is an important diagnostic characteristic given the propositions, then site to site transfer should be taken into account during the evaluation of observations. In this work we demonstrate the ways in which site to site transfer can be built into Bayesian networks when carrying out activity level evaluations of forensic biology findings. We explore the effects of considering qualitative vs quantitative categorisation of DNA results. We also show the importance of taking into account multiple individual's DNA being transferred (such as unknown or wearer DNA), even if the main focus of the evaluation is the activity of one individual.
Assuntos
Teorema de Bayes , DNA , Humanos , DNA/genética , Genética Forense/métodos , Impressões Digitais de DNARESUMO
The DNA Commission of the International Society for Forensic Genetics (ISFG) has developed a set of nomenclature recommendations for short tandem repeat (STR) sequences. These recommendations follow the 2016 considerations of the DNA Commission of the ISFG, incorporating the knowledge gained through research and population studies in the intervening years. While maintaining a focus on backward compatibility with the CE data that currently populate national DNA databases, this report also looks to the future with the establishment of recommended minimum sequence reporting ranges to facilitate interlaboratory comparisons, automated solutions for sequence-based allele designations, a suite of resources to support bioinformatic development, guidance for characterizing new STR loci, and considerations for incorporating STR sequences and other new markers into investigative databases.
Assuntos
Genética Forense , Repetições de Microssatélites , Terminologia como Assunto , Humanos , Genética Forense/métodos , Sociedades Científicas , Impressões Digitais de DNA , Bases de Dados de Ácidos NucleicosRESUMO
The petrous bone contains significantly higher amounts of DNA than any other human bone. Because of highly destructive sampling and because it is not always part of the recovered remains, the need for alternative sources of DNA is important. To identify additional optimal bone types, petrous bones were compared to femurs, tali, and calcanei sampled from 66 adult skeletons from two distinct modern-era Christian cemeteries. An extraction method employing full demineralization was used to obtain DNA, real-time PCR quantification to ascertain DNA quantity and degradation, and a commercial forensic short tandem repeats (STR) PCR amplification kit to determine genetic profiles. Statistical analysis was performed to explore the differences in DNA yield, DNA degradation, and success of STR amplification. A systematic studies exploring intra-skeletal variability in DNA preservation including various excavation sites differing by time period and geographical position are rare, and the second part of the investigation was based on a comparison of both archaeological sites, which allowed us to compare the effect of different post-mortem intervals and environmental conditions on DNA preservation. The older burial site in Crnomelj was active between the 13th and 18th century, whereas the more recent Polje burial was in use from the 16th to 19th century, creating different temporal and geographical environments. Results for the Crnomelj burial site revealed that the petrous bone outperformed all other bone types studied, except the calcaneus. At the Polje archeological site calcanei, tali, and femurs yielded the same STR typing success as petrous bones. The results obtained highlight the importance of careful bone sample selection for DNA analysis of aged skeletal remains. In addition to petrous bones, calcanei were found to be an alternative source of DNA when older burial sites are investigated. When more recent burial sites are processed, calcanei, tali, and femurs should be sampled besides petrous bones, not only because they exhibited good performance, but also because of easier sampling and easier grinding in the case of trabecular bones. This study contributes valuable insights into the potential use of various skeletal types as a source of DNA for investigation of aged skeletal remains, and it offers practical implications for forensic and archaeological investigations.
Assuntos
Impressões Digitais de DNA , DNA , Repetições de Microssatélites , Reação em Cadeia da Polimerase em Tempo Real , Humanos , Impressões Digitais de DNA/métodos , Masculino , DNA/análise , DNA/isolamento & purificação , Adulto , Pessoa de Meia-Idade , Feminino , Restos Mortais , Degradação Necrótica do DNA , Idoso , Fêmur/química , Fêmur/anatomia & histologia , História Medieval , Osso e Ossos/química , Osso Petroso/química , Osso Petroso/anatomia & histologia , Idoso de 80 Anos ou mais , Antropologia Forense/métodos , Adulto Jovem , Calcâneo/anatomia & histologiaRESUMO
More than 1200 civilians and military were killed in cities and villages by the Hamas attack on October 7th, 2023. The bodies and body-parts had to be identified and released for burial. This report outlines the challenges and mode of operation of the massive disaster victim identification (DVI) efforts. Bodies were delivered to a central mortuary. Each body was coded and undressed for external inspection and documentation of physical elements. Digital fingerprints were recorded and blood or toenails sampled for DNA. Odontology exams were performed by dentists describing dentition, aided by computerized tomography (CT). Whole-body CT was performed in cases the bodies were disfigured or burned from the second week. Simultaneously, families of missing civilians provided physical elements to the police to extract the DNA for antemortem documentation. The police took the responsibility over the reconciliation, which was based on comparison of the ante-mortem and post-mortem fingerprints, aided by DNA profile matching, odontology examination, clinical and/or radiological findings performed by forensic practitioners. Secondary identification elements were used assure the families regarding the identification. Precise scientific identification a was a priority, even if it slowed the rate of bodies release. Families were allowed to view their relative either at the mortuary or before burial. The DVI process required cooperation between several governmental agencies and police. To maximize the effectiveness, a synchronized approach should be adopted, specifying communication channels between the partners and dividing the responsibilities. The DVI should be led by a single, experienced authority to ensure interdisciplinary teamwork. This catastrophe required personal resilience of the teams for rapid and efficient functioning and communication between the partners.
Assuntos
Restos Mortais , Impressões Digitais de DNA , Incidentes com Feridos em Massa , Terrorismo , Humanos , Israel , Sepultamento , Antropologia Forense , Dermatoglifia , Tomografia Computadorizada por Raios X , Vítimas de Desastres , Polícia , Práticas Mortuárias , Odontologia Legal/métodosRESUMO
Insertion or deletion (InDel), a genetic marker with short insertion/deletion fragment length polymorphism, is widely used in the field of forensic biological research. The Guizhou Shui (Shui) ethnic group and Guizhou Dong (Dong) ethnic group are located in the southwestern region of China, with rich historical and cultural background. In this study, a self-developed panel included 56 ancestry informative marker (AIM)-InDel loci on the autosomes, three InDel loci on the Y chromosome, and one sex-determined Amelogenin locus. Firstly, we used the 56 autosomal loci to assess the forensic individual identification and paternity testing abilities in both the Shui and Dong groups. The cumulative probability of match and probability of exclusion for the Shui and Dong groups were 2.228×10-15 and 0.991518139; 7.604×10-16 and 0.992253273, respectively. In addition, we also conducted in-depth analyses for the genetic backgrounds and structures of the Shui and Dong groups based on 56 AIM-InDel loci. This research has found that the Shui and Dong groups have close genetic relationships with the East Asian populations. Meanwhile, we also found that the Shui group has a close genetic distance with Chinese Dai in Xishuangbanna (CDX). These insights provide vital information for the genetic structures of the Shui and Dong groups, as well as basic population data and molecular biological evidence support for individual identification and biogeographic ancestry inference in forensic genetic field.
Assuntos
Cromossomos Humanos Y , Impressões Digitais de DNA , Etnicidade , Genética Populacional , Feminino , Humanos , Masculino , Amelogenina/genética , China/etnologia , Etnicidade/genética , Frequência do Gene , Marcadores Genéticos , Perfil Genético , Mutação INDEL , Reação em Cadeia da Polimerase , Polimorfismo Genético , População do Leste Asiático/genéticaRESUMO
Improvised explosive devices (IEDs) can be assembled directly from daily items and are easily purchasable and distributable internationally, owing to the absence of government export permits. Hence, their origins are not readily revealed, and they can pose significant adverse effects despite their low manufacturing costs. In this study, the feasibility of identifying fingerprints and deoxyribo nucleic acid (DNA) profiles in various IEDs and samples is investigated. Additionally, the relative positions of debris are identified to set the scope of on-site inspection at terrorist scenes. All samples are categorized into porous and non-porous materials, and LMG test, extraction, quantification, and short tandem repeat (STR) analysis are conducted to view the DNA profile. For fingerprinting, 1,2-IND and CA are utilized for development, followed by quality-control analysis. Although sample acquisition is impossible in some experiments, DNA profiling and fingerprint analysis are possible for all, thus allowing mapping to be performed. This study shows that even when terrorist bombing occurs, if evidence with minimal damage is detected at the scene, then STR profiles and fingerprints can be obtained at a level suitable for AFIS usage. Furthermore, accumulating mapping results from numerous experiments significantly aids in determining the scope of evidence acquisition.