Highlights • The Spanish and Portuguese-speaking working group of ISFG has designed a simulated exercise on database comparisons for human identification. • The aim of the exercise was to introduce ...participants to the complexity of the identification of victims in disasters (DVI) or missing persons identification (MPI) scenarios. • The exercise focused on biostatistics for direct matching and kinship analysis in a Bayesian framework. • This study demonstrates that although a DNA forensic laboratory is experienced in kinship or criminalistics analysis, additional training in DVI or MPI is necessary in order to properly investigate these scenarios.
Abstract The aim of the study was to perform the genetic identification of a human cranium from a Second World War gravesite in Slovenia and find out if it belonged to the mother of a woman used as a ...family reference. Both genetic and anthropological examinations were carried out. The genetic examination was performed on 2 M and petrous bone. Prior to DNA isolation 0.5 g of tooth and bone powder was decalcified. The DNA was purified in a Biorobot EZ1 (Qiagen) device. The nuclear DNA of the samples was quantified and short tandem repeat (STR) typing performed using two different autosomal and Y-STR kits. Up to 22.4 ng DNA/g of powder was obtained from samples analyzed. We managed to obtain nuclear DNA for successful STR typing from the left second molar and from the petrous bone. Full autosomal genetic profile including amelogenin locus revealed the male origin of the cranium that was further confirmed by the analyses of Y-STRs. The same conclusions were adopted after the anthropological analysis which identified the cranium as that of a very young Caucasoid male. The male origin of the cranium rejected the possibility of motherhood for the compared daughter. For traceability in the event of contamination, we created an elimination database including genetic profiles of the nuclear and Y-STRs of all persons that had been in contact with the analyzed cranium and no match was found.
The paper introduces a logical framework for a Missing People Detection Scheme that harnesses the capabilities of the Internet of Things (IoT) alongside Human-Computer Interaction (HCI) technology. ...By amalgamating data-driven methodologies, deep learning advancements, and facial recognition technology, the scheme endeavors to enhance the efficiency of identifying and resolving missing person cases. Commencing with the meticulous collection and refinement of extensive data concerning missing individuals, encompassing social context, disappearance timing, and location, the scheme ensures data accuracy and reliability for subsequent analysis. Deep learning algorithms, particularly supervised models, are then deployed to construct a predictive model for missing person identification. Through iterative parameter adjustments during training, the model discerns patterns and correlations within the data to minimize prediction errors. Subsequent evaluation using separate test data measures the model's generalization capability and effectiveness through performance metrics. Addressing the challenge of missing data, the scheme deliberately incorporates incomplete information to ensure the model's predictive capacity despite such limitations. Case registration initiates the identification process, where uploaded images and details of missing individuals are stored and processed in a database. This lays the groundwork for facial recognition tasks, employing facial encoding techniques to extract distinctive features from uploaded images. Comparison of encoded features with stored data in the database facilitates identifying potential matches between found individuals and reported missing persons. Furthermore, Siamese Networks augment the scheme's capabilities for facial image comparison, leveraging deep learning to assess similarity and aid in the identification process. By offering a comprehensive solution to the complexities of missing person identification, the proposed scheme aims to contribute significantly to resolving such cases and reuniting individuals with their families.
Stories of the missing offer profound insights into the tension between how political systems see us and how we see each other. The search for people who go missing as a result of war, political ...violence, genocide, or natural disaster reveals how forms of governance that objectify the person are challenged. Contemporary political systems treat persons instrumentally, as objects to be administered rather than as singular beings: the apparatus of government recognizes categories, not people. In contrast, relatives of the missing demand that authorities focus on a particular person: families and friends are looking for someone who to them is unique and irreplaceable.
InMissing, Jenny Edkins highlights stories from a range of circumstances that shed light on this critical tension: the aftermath of World War II, when millions in Europe were displaced; the period following the fall of the World Trade Center towers in Manhattan in 2001 and the bombings in London in 2005; searches for military personnel missing in action; the thousands of political "disappearances" in Latin America; and in more quotidian circumstances where people walk out on their families and disappear of their own volition. When someone goes missing we often find that we didn't know them as well as we thought: there is a sense in which we are "missing" even to our nearest and dearest and even when we are present, not absent. In this thought-provoking book, Edkins investigates what this more profound "missingness" might mean in political terms.
•271,934 tri-allelic SNPs were identified in the 1000 Genomes Phase III variant catalog and data has been compiled in Mendeley Data for free access.•From this extensive dataset 8,705 SNPs had ...heterozygosity values above 0.5 - the maximum value of perfect binary SNPs (0.5:0.5 allele frequencies).•A large-scale forensic identification multiplex was constructed for MPS, comprising 1,241 autosomal plus 29 X tri-allelic SNPs.•Approximately 5 % of tri-allelic SNPs selected for the large-scale MPS panel gave three-genotype patterns in one individual or discordant genotypes.•The need for caution and detailed scrutiny of multiple-allele variant data is highlighted when designing future forensic SNP panels.
In a directed search of 1000 Genomes Phase III variation data, 271,934 tri-allelic single nucleotide polymorphisms (SNPs) were identified amongst the genotypes of 2,504 individuals from 26 populations. The majority of tri-allelic SNPs have three nucleotide substitution-based alleles at the same position, while a much smaller proportion, which we did not compile, have a nucleotide insertion/deletion plus substitution alleles. SNPs with three alleles have higher discrimination power than binary loci but keep the same characteristic of optimum amplification of the fragmented DNA found in highly degraded forensic samples. Although most of the tri-allelic SNPs identified had one or two alleles at low frequencies, often single observations, we present a full compilation of the genome positions, rs-numbers and genotypes of all tri-allelic SNPs detected by the 1000 Genomes project from the more detailed analyses it applied to Phase III sequence data. A total of 8,705 tri-allelic SNPs had overall heterozygosities (averaged across all 1000 Genomes populations) higher than the binary SNP maximum value of 0.5. Of these, 1,637 displayed the highest average heterozygosity values of 0.6-0.666. The most informative tri-allelic SNPs we identified were used to construct a large-scale human identification panel for massively parallel sequencing, designed for the identification of missing persons. The large-scale MPS identification panel comprised: 1,241 autosomal tri-allelic SNPs and 29 X tri-allelic SNPs (plus 46 microhaplotypes adapted for genotyping from reduced length sequences). Allele frequency estimates are detailed for African, European, South Asian and East Asian population groups plus the Peruvian population sampled by 1000 Genomes for the 1,270 tri-allelic SNPs of the final MPS panel. We describe the selection criteria, kinship simulation experiments and genomic analyses used to select the tri-allelic SNP components of the panel. Approximately 5 % of the tri-allelic SNPs selected for the large-scale MPS identification panel gave three-genotype patterns in single individual samples or discordant genotypes for genomic control DNAs. A likely explanation for some of these unreliably genotyped loci is that they map to multiple sites in the genome - highlighting the need for caution and detailed scrutiny of multiple-allele variant data when designing future forensic SNP panels, as such patterns can arise from common structural variation in the genome, such as segmental duplications.
The Spanish and Portuguese-Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) has organized a second collaborative exercise on a simulated case of Disaster Victim ...Identification (DVI), with the participation of eighteen laboratories. The exercise focused on the analysis of a simulated plane crash case of medium-size resulting in 66 victims with varying degrees of fragmentation of the bodies (with commingled remains). As an additional difficulty, this second exercise included 21 related victims belonging to 6 families among the 66 missings to be identified. A total number of 228 post-mortem samples were represented with aSTR and mtDNA profiles, with a proportion of partial aSTR profiles simulating charred remains. To perform the exercise, participants were provided with aSTR and mtDNA data of 51 reference pedigrees —some of which deficient—including 128 donors for identification purposes. The exercise consisted firstly in the comparison of the post-mortem genetic profiles in order to re-associate fragmented remains to the same individual and secondly in the identification of the re-associated remains by comparing aSTR and mtDNA profiles with reference pedigrees using pre-established thresholds to report a positive identification. Regarding the results of the post-mortem samples re-associations, only a small number of discrepancies among participants were detected, all of which were from just a few labs. However, in the identification process by kinship analysis with family references, there were more discrepancies in comparison to the correct results. The identification results of single victims yielded fewer problems than the identification of multiple related victims within the same family groups. Several reasons for the discrepant results were detected: a) the identity/non-identity hypotheses were sometimes wrongly expressed in the likelihood ratio calculations, b) some laboratories failed to use all family references to report the DNA match, c) In families with several related victims, some laboratories firstly identified some victims and then unnecessarily used their genetic information to identify the remaining victims within the family, d) some laboratories did not correctly use “prior odds” values for the Bayesian treatment of the episode for both post-mortem/post-mortem re-associations as well as the ante-mortem/post-mortem comparisons to evaluate the probability of identity. For some of the above reasons, certain laboratories failed to identify some victims. This simulated “DNA-led” identification exercise may help forensic genetic laboratories to gain experience and expertize for DVI or MPI in using genetic data and comparing their own results with the ones in this collaborative exercise.
•The GHEP-ISFG has designed a second “DNA-led” DVI exercise in a simulated air crash.•This exercise can be useful for testing DVI using the data and results provided.•The exercise is focused on direct matching and kinship analysis in a Bayesian framework.•This exercise sheds light on problems that a laboratory can face in DVI scenarios.
STR analysis of DNA extracted from skeletal samples can play an important role in the identification of missing persons. Here we present a method for the extraction of DNA from skeletal samples ...involving complete demineralization and digestion of the sample, followed by purification by silica binding. This method, together with the multiplex STR typing approach also presented, has proven highly successful in the recovery of DNA profiles from degraded, aged skeletal remains from a wide range of environmental contexts. The methodological steps presented include bone decontamination and grinding, DNA extraction, repurification in the case of highly inhibited samples, quantification, STR multiplex amplification, and profile reporting guidelines. However, the conditions applied for amplification and the criteria for allele calling and profile submission must be based on the results of each laboratory's internal validation experiments involving the type of samples relevant to the project at hand. The methods presented here have permitted large-scale DNA-based identification of persons missing from mass disasters and armed conflict.
Prior probabilities represent a core element of the Bayesian probabilistic approach to relatedness testing. This letter opinions on the commentary Use of prior odds for missing persons ...identifications by Budowle et al., published recently in this journal. Contrary to Budowle et al., we argue that the concept of prior probabilities (i) is not endowed with the notion of objectivity, (ii) is not a case for computation, and (iii) does not require new guidelines edited by the forensic DNA community--as long as probability is properly considered as an expression of personal belief.
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