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Genetic assessment of highly incinerated and/or degraded human skeletal material is a persistent challenge in forensic DNA analysis, including identifying victims of mass disasters. Few studies have investigated the impact of thermal degradation on whole‐genome single‐nucleotide polymorphism (SNP) quality and quantity using next‐generation sequencing (NGS). We present whole‐genome SNP data obtained from the bones and teeth of 27 fire victims using two DNA extraction techniques. Extracts were converted to double‐stranded DNA libraries then enriched for whole‐genome SNPs using unpublished biotinylated RNA baits and sequenced on an Illumina NextSeq 550 platform. Raw reads were processed using the EAGER (Efficient Ancient Genome Reconstruction) pipeline, and the SNPs filtered and called using FreeBayes and GATK (v. 3.8). Mixed‐effects modeling of the data suggest that SNP variability and preservation is predominantly determined by skeletal element and burn category, and not by extraction type. Whole‐genome SNP data suggest that selecting long bones, hand and foot bones, and teeth subjected to temperatures <350°C are the most likely sources for higher genomic DNA yields. Furthermore, we observed an inverse correlation between the number of captured SNPs and the extent to which samples were burned, as well as a significant decrease in the total number of SNPs measured for samples subjected to temperatures >350°C. Our data complement previous analyses of burned human remains that compare extraction methods for downstream forensic applications and support the idea of adopting a modified Dabney extraction technique when traditional forensic methods fail to produce DNA yields sufficient for genetic identification. [ABSTRACT FROM AUTHOR]

Massively parallel sequencing allows for integrated genotyping of different types of forensic markers, which reduces DNA consumption, simplifies experimental processes, and provides additional sequence-based genetic information. The STRseqTyper122 kit genotypes 63 autosomal STRs, 16 X-STRs, 42 Y-STRs, and the Amelogenin locus. Amplicon sizes of 117 loci were below 300 bp. In this study, MiSeq FGx sequencing metrics for STRseqTyper122 were presented. The genotyping accuracy of this kit was examined by comparing to certified genotypes of NIST standard reference materials and results from five capillary electrophoresis-based kits. The sensitivity of STRseqTyper122 reached 125 pg, and > 80% of the loci were correctly called with 62.5 pg and 31.25 pg input genomic DNA. Repeatability, species specificity, and tolerance for DNA degradation and PCR inhibitors of this kit were also evaluated. STRseqTyper122 demonstrated reliable performance with routine case-work samples and provided a powerful tool for forensic applications. [ABSTRACT FROM AUTHOR]

The quantification of human DNA extracts from forensic samples plays a key role in the forensic genetics process, ensuring maximum efficiency and avoiding repeated analyses, over-amplified samples, or unnecessary examinations. In our laboratory, we use the Quantifiler® Trio system to quantify DNA extracts from a wide range of samples extracted from traces (bloodstains, saliva, semen, tissues, etc.), including swabs from touched objects, which are very numerous in the forensic context. This method has been extensively used continuously for nine years, following an initial validation process, and is part of the ISO/IEC 17025 accredited method. In routine practice, based on the quantitative values determined from the extracts of each trace, we use a standard method or a low-copy-number method that involves repeating the amplification with the generation of a consensus genetic profile. Nowadays, when the quantification results are less than 0.003 ng/μL in the minimum extraction volume (40 μL), we do not proceed with the DNA extract analysis. By verifying the limits of the method, we make a conscious cost-benefit choice, in particular by using the least amount of DNA needed to obtain sufficiently robust genetic profiles appropriate for submission to the Italian DNA Forensic Database. In this work, we present a critical re-evaluation of this phase of the method, which is based on the use of standard curves obtained from the average values of the control DNA analysed in duplicate. Considering the various contributions to uncertainty that are difficult to measure, such as manual pipetting or analytical phases carried out by different operators, we have decided to thoroughly investigate the contribution of variability in the preparation of calibration curves to the final results. Thus, 757 samples from 20 independent experiments were re-evaluated using two different standards for the construction of curves, determining the quantitative differences between the two methods. The experiments also determined the parameters of the slope, Y-intercept, R2, and the values of the synthetic control probe to verify how these parameters can provide information on the final outcome of each analysis. The outcome of this revalidation demonstrated that it is preferable to use quantification ranges rather than exact quantitative limits before deciding how to analyse the extracts via PCR or forgoing the determination of profiles. Additionally, we present some preliminary data related to the analysis of samples that would not have been analysed based on the initial validation, from which genetic profiles were obtained after applying a concentration method to the extracts. Our goal is to improve the accredited analytical method, with a careful risk assessment as indicated by accreditation standards, ensuring that no source of evidence is lost in the reconstruction of a criminal event. [ABSTRACT FROM AUTHOR]

Comparisons of DNA profiles recovered from the crime-scene and a person through short tandem repeat (STR) analysis using capillary electrophoresis (CE) is the gold standard method of determining a match. A comparison of STR profiles generated using CE to massively parallel sequencing (MPS) methods was undertaken. The results showed CE methods recovered high percentages of autosomal or Y-STR markers individually, however, MPS produced more information at low inputs and a higher number of STR markers overall, showing the potential of MPS to provide additional data to assist in solving major crimes. [ABSTRACT FROM AUTHOR]

We report on a comparison of the performance of the Applied Biosystems® SeqStudioTM Genetic Analyzer with the 3500 Genetic Analyzer when analysing trace DNA samples. Totally, 162 profiles generated from 'trace DNA' were analysed on both instruments with comparable number of alleles detected, relative fluorescence units (RFU) and likelihood ratio (LR) values. The SeqStudioTM was found to be suitable for the analysis of trace DNA samples. [ABSTRACT FROM AUTHOR]

Comparisons of DNA profiles recovered from the crime-scene and a person through short tandem repeat (STR) analysis using capillary electrophoresis (CE) is the gold standard method of determining a match. A comparison of STR profiles generated using CE to massively parallel sequencing (MPS) methods was undertaken. The results showed CE methods recovered high percentages of autosomal or Y-STR markers individually, however, MPS produced more information at low inputs and a higher number of STR markers overall, showing the potential of MPS to provide additional data to assist in solving major crimes. [ABSTRACT FROM AUTHOR]

We report on a comparison of the performance of the Applied Biosystems® SeqStudioTM Genetic Analyzer with the 3500 Genetic Analyzer when analysing trace DNA samples. Totally, 162 profiles generated from 'trace DNA' were analysed on both instruments with comparable number of alleles detected, relative fluorescence units (RFU) and likelihood ratio (LR) values. The SeqStudioTM was found to be suitable for the analysis of trace DNA samples. [ABSTRACT FROM AUTHOR]

The X chromosome is one of the two sex chromosomes found in humans and other mammals. It plays a crucial role in determining an individual's sex and contains genetic information that can be useful in forensic and human identity testing. Unlike autosomal DNA, which is inherited from both parents, the X chromosome is inherited differently in males and females, making it useful in certain types of analyses. In forensic investigations, the X chromosome can be used to determine the sex of an individual, which can be useful in identifying potential suspects or victims. Additionally, X chromosome analysis can be used to link evidence samples to a particular individual or to exclude individuals as potential contributors of the evidence. This can be particularly useful in cases where the evidence sample is a mixture of DNA from multiple individuals. In human identity testing, the X chromosome can be used in situations where other types of DNA analysis are not possible or inconclusive. For example, in cases where a potential parent is unavailable for testing, analysis of the X chromosome can be used to determine if a child is likely to be their biological offspring. Similarly, in cases where traditional autosomal DNA analysis is inconclusive, X chromosome analysis can be used to provide additional information about the biological relationship between individuals. However, there are some limitations to the use of X chromosome analysis in forensic and human identity testing. One limitation is that it is not as informative as autosomal DNA analysis, as it contains less genetic information. Additionally, the inheritance patterns of the X chromosome can be complex, particularly in cases where there are multiple generations involved. Therefore, X chromosome analysis should be interpreted in conjunction with other types of DNA analysis and other forms of evidence to ensure accurate and reliable results. Overall, the use of X chromosome analysis in forensic and human identity testing can provide important information in certain situations, particularly where traditional DNA analysis is not possible or inconclusive. As such, it is an important tool in the fields of forensic science and human identification. [ABSTRACT FROM AUTHOR]

There is interest in comparing the output, principally the likelihood ratio, from the two probabilistic genotyping software EuroForMix (EFM) and STRmix™. Many of these comparison studies are descriptive and make little or no effort to diagnose the cause of difference. There are fundamental differences between EFM and STRmix™ that are causative of the largest set of likelihood ratio differences. This set of differences is for false donors where there are many instances of LRs just above or below 1 for EFM that give much lower LRs in STRmix™. This is caused by the separate estimation of parameters such as allele height variance and mixture proportion using MLE under Hp and Ha for EFM. This can result in very different estimations of these parameters under Hp and Ha. It results in a departure from calibration for EFM in the region of LRs just above and below 1. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Criminology & Criminal Justice is the property of University of Toronto Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Generating degraded DNA samples can be useful for forensic DNA research as this can mimic the condition of crime scene samples and results from such samples. Methods which use quick and cost-effective ultraviolet light (UV) exposure can be utilized to degrade DNA but are not well documented. This study aimed to establish a procedure and define the parameters required to generate Short Tandem Repeat (STR) profiles at different degradation levels. UV exposure times between 0 and 60 s were tested using genomic and control DNA. Sample eluates were quantified with QuantifilerTM Trio pre- and post-UV exposure, and select samples were profiled using PowerPlex® 21. Quantification data and STR profiles were analysed to identify metrics which indicated degradation severity. Samples were observed to be degraded by UV exposure as evidenced by established DNA degradation markers. No specific metric was identified to reliably determine the severity of sample degradation, but it was noted that UV exposure between 5 and 10 s resulted in mild degradation, between 15 and 25 s generated moderate degradation, and between 45 and 60 s resulted in severe degradation in STR profiles. This study indicates that quantification before and after UV exposure may be useful to estimate the degree of degradation via one quantification target. [ABSTRACT FROM AUTHOR]

Generating degraded DNA samples can be useful for forensic DNA research as this can mimic the condition of crime scene samples and results from such samples. Methods which use quick and cost-effective ultraviolet light (UV) exposure can be utilized to degrade DNA but are not well documented. This study aimed to establish a procedure and define the parameters required to generate Short Tandem Repeat (STR) profiles at different degradation levels. UV exposure times between 0 and 60 s were tested using genomic and control DNA. Sample eluates were quantified with QuantifilerTM Trio pre- and post-UV exposure, and select samples were profiled using PowerPlex® 21. Quantification data and STR profiles were analysed to identify metrics which indicated degradation severity. Samples were observed to be degraded by UV exposure as evidenced by established DNA degradation markers. No specific metric was identified to reliably determine the severity of sample degradation, but it was noted that UV exposure between 5 and 10 s resulted in mild degradation, between 15 and 25 s generated moderate degradation, and between 45 and 60 s resulted in severe degradation in STR profiles. This study indicates that quantification before and after UV exposure may be useful to estimate the degree of degradation via one quantification target. [ABSTRACT FROM AUTHOR]

Autosomal short tandem repeat (STR) population data collected from a well characterized population are needed to correctly assigning the weight of DNA profiles in the courtroom and widely used for ancestral analyses. In this study, allele frequencies for the 15 autosomal short tandem repeat (STR) loci included in the AmpFlSTR® Identifiler® plus kit (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, VWA, TPOX, D18S51, D5S818, FGA) were obtained by genotyping 332 unrelated individuals of Ghanaian origin. Statistical tests on STR genotype data showed no significant departure from Hardy–Weinberg equilibrium (HWE). The overall match probability, combined power of exclusion and combined power of discrimination for these loci were 1 in 3.85 × 1017, 0.99999893 and 0.99999998, respectively. Polymorphic information content (PIC) greater than 0.70 was observed for all loci except TH01 and D13S317. These statistical parameters confirm that this combination of loci is valuable for forensic identification and parentage analysis. Our results were also compared with those for 20 other human populations analyzed for the same set of markers. We observed that the Ghanaian population grouped with other African populations in two-dimensional principal coordinate (PCO) and a neighbor-joining (N-J) data mapping and placed closest to Nigerians. This observation reflects cultural similarities and geographical factors, coupled with the long history of migration and trading activities between Ghana and Nigeria. Our report provides what we believe to be the first published autosomal STR data for the general Ghanaian population using 15 loci genotyped using the AmpFlSTR® Identifiler® plus kit methodology. Our data show that the loci tested have sufficient power to be used reliably for DNA profiling in forensic casework and help to elucidate the genetic history of people living in the country. [ABSTRACT FROM AUTHOR]

This study assessed the usefulness of DNA quantification to predict the success of historical samples when analyzing SNPs, mtDNA, and STR targets. Thirty burials from six historical contexts were utilized, ranging in age from 80 to 800 years postmortem. Samples underwent library preparation and hybridization capture with two bait panels (FORCE and mitogenome), and STR typing (autosomal STR and Y-STR). All 30 samples generated small (~80 bp) autosomal DNA target qPCR results, despite mean mappable fragments ranging from 55–125 bp. The qPCR results were positively correlated with DNA profiling success. Samples with human DNA inputs as low as 100 pg resulted in ≥80% FORCE SNPs at 10X coverage. All 30 samples resulted in mitogenome coverage ≥100X despite low human DNA input (as low as 1 pg). With PowerPlex Fusion, ≥30 pg human DNA input resulted in >40% of auSTR loci. At least 59% of Y-STR loci were recovered with Y-target qPCR-based inputs of ≥24 pg. The results also indicate that human DNA quantity is a better predictor of success than the ratio of human to exogenous DNA. Accurate quantification with qPCR is feasible for historical bone samples, allowing for the screening of extracts to predict the success of DNA profiling. [ABSTRACT FROM AUTHOR]

Copyright of Forensic Science & Technology is the property of Institute of Forensic Science, Ministry of Public Security and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Previous studies examining whether splitting the DNA extract for replicate amplification versus maximizing the template available for a 'one-shot' amplification either examined the benefits of using replicates (without a comparison to a single amplification), or used semi-continuous probabilistic software that ignores peak height information. In this study, we use a fully continuous probabilistic genotyping software to compare the effectiveness of amplifying a single sample compared to splitting the sample and conducting a joint analysis of replicate amplifications. We show that the one-shot approach is marginally better than splitting the DNA extract across a range of contributor numbers and template amounts. Where there is unexpected peak height variability or drop-in within the profile not modelled during interpretation, a replicate approach may be better. [ABSTRACT FROM AUTHOR]

Crime laboratories have been faced with large casework backlogs due to lengthy processing times, limited resources and scientists, and rising crime rates. Evidence related to sexual assault crimes, specifically sexual assault kits (SAKs), heavily contribute to the reported backlogs. Although more sensitive, faster chemistries and automated techniques have been implemented over the years, the traditional STR workflow remains relatively unchanged. Enhanced workflows such as direct PCR and Rapid DNA have the potential to streamline the processing of forensic evidence items including those commonly submitted in SAKs, but the FBI QAS guidelines restrict CODIS‐approved labs from implementing these methods for forensic samples. Recent studies have shown decreased turnaround times and improved or comparable profiling success with both approaches. However, review of the literature shows a lack of in‐depth research comparing traditional DNA workflows to faster and more sensitive direct PCR and/or Rapid DNA approaches for evidentiary samples, especially for SAKs. By providing the forensic science and criminal justice communities with the strengths and limitations of direct PCR and Rapid DNA methods, stakeholders and policy makers may be better informed. [ABSTRACT FROM AUTHOR]

CRISPR-Cas technology has revolutionized the field of biotechnology with its precise therapeutic use from genetic as well as infectious diseases point of view. This technology is rapidly evolving to single tool enabling site-directed cut in the genome and highly specific activation or inhibition of gene expression or the exchange of single bases. Besides clinical applications, CRISPR-Cas technology has also shown promising use in the field of forensic DNA analysis. Enrichment of targeted genetic marker for identification followed by sequencing and non-PCR–dependent technique ensures the use of CRISPR-Cas technology in challenging forensic biological samples. The use of this advanced technology is also deemed helpful in mixed profile attribution, mostly in LCN contributors and the generation of a useful DNA profile in degraded samples. Besides its useful applications in forensic DNA analysis, CRISPR-Cas technology poses a huge threat from the generation of ghost DNA profiles by modification/alteration of target genetic markers. Forensic DNA analysts should carry out analysis of additional markers such as non-CODIS markers, Y-, X-chromosome markers, and mitochondrial DNA sequencing in a suspected ghost DNA profile case. Key points: • CRISPR-Cas9 technique is useful in analyzing LCN, mixed and degraded samples • Alteration of DNA using this technique can lead to generation of ghost DNA profiles • Alternative genetic markers and methylation pattern may detect a ghost DNA profile [ABSTRACT FROM AUTHOR]

Interpreting forensic DNA signal is arduous since the total intensity is a cacophony of signal from noise, artifact, and allele from an unknown number of contributors (NOC). An alternate to traditional bulk‐processing pipelines is a single‐cell one, where the sample is collected, and each cell is sequestered resulting in n single‐source, single‐cell EPGs (scEPG) that must be interpreted using applicable strategies. As with all forensic DNA interpretation strategies, high quality electropherograms are required; thus, to enhance the credibility of single‐cell forensics, it is necessary to produce an efficient direct‐to‐PCR treatment that is compatible with prevailing downstream laboratory processes. We incorporated the semi‐automated micro‐fluidic DEPArray™ technology into the single‐cell laboratory and optimized its implementation by testing the effects of four laboratory treatments on single‐cell profiles. We focused on testing effects of phosphate buffer saline (PBS) since it is an important reagent that mitigates cell rupture but is also a PCR inhibitor. Specifically, we explored the effect of decreasing PBS concentrations on five electropherogram‐quality metrics from 241 leukocytes: profile drop‐out, allele drop‐out, allele peak heights, peak height ratios, and scEPG sloping. In an effort to improve reagent use, we also assessed two concentrations of proteinase K. The results indicate that decreasing PBS concentrations to 0.5X or 0.25X improves scEPG quality, while modest modifications to proteinase K concentrations did not significantly impact it. We, therefore, conclude that a lower than recommended proteinase K concentration coupled with a lower than recommended PBS concentration results in enhanced scEPGs within the semi‐automated single‐cell pipeline. [ABSTRACT FROM AUTHOR]

Due to recent improvements in forensic DNA testing kit sensitivity, there has been an increased demand in the criminal justice community to revisit past convictions or cold cases. Some of these cases have little biological evidence other than touch DNA in the form of archived latent fingerprint lift cards. In this study, a previously developed optimised workflow for this sample type was tested on aged fingerprints to determine if improved short tandem repeat (STR) profiles could be obtained. Two-year-old samples processed with the optimised workflow produced an average of approximately five more STR alleles per profile over the traditional method. The optimised workflow also produced detectable alleles in samples aged out to 28 years. Of the methods tested, the optimised workflow resulted in the most informative profiles from evidence samples more representative of the forensic need. This workflow is recommended for use with archived latent fingerprint samples, regardless of the archival time. The use of the optimised workflow on aged archived latent fingerprint (ALFP) lift card samples (aged 2–28 years) improves the number of STR alleles recovered, providing more discriminatory STR profiles than those processed using the traditional workflow. Interpretable STR alleles can be detected from ALFP lift card samples stored as long as 28 years when the optimised procedures are followed. The use of individual laboratory-sterilised tools for sample preparation and the addition of a re-purification step with Centri-Sep columns in the recommended optimised workflow seem to limit the ability to detect low-level secondary DNA sources. [ABSTRACT FROM AUTHOR]

The present study was designed to explore the STR diversity and genomic history of the inhabitants of Nayagarh district of Odisha, India. We also tested the proficiency of the most recent, new generation PowerPlexR Y23 multiplex system for forensic characterisation and to decipher the phylogenetic affinities. The genetic diversity and polymorphism among 236 healthy unrelated male volunteers from Nayagarh district of Odisha, India was investigated. This investigation was carried out via 23 Y-chromosomal STRs using capillary electrophoresis. A total 223 unique haplotypes were reported. Discrimination capacity (DC), gene diversity (GD) and power of discrimination (PD) were observed as 0.945, 0.999999999998333, and 0.99999999999794, respectively. Polymorphic information content (PIC) and matching probability (PM) were reported as 0.999999999925535 and 2.06 × 10−12, respectively. Simultaneously, the haplogroup analysis characterised with C2, E1b1a, E1b1b, G2a, H1, I2a, J2a, J2b, L, O, O1, O2, Q, R1a, R2, and T haplogroups, disclosing the possible geographical relatedness of the studied population to different areas of the world. Phylogenetic analysis with previously reported Indian and Asian populations showed the genetic closeness of the studied population to different Indian populations and the Bangladeshi population of Dhaka, whereas the Bhotra population of Odisha and Han population of China showed much less genetic affinity. [ABSTRACT FROM AUTHOR]

Y-chromosome short tandem repeat (Y-STR) markers have been widely used in forensic applications and usually show monoallelic or diallelic genotypic patterns at certain double-copied loci. In this study, we have found 13 samples among 703 males with multi-alleles at the DYS385ab locus, including one with five mutant alleles, nine with four, and three with three. The frequency of abnormal DYS385ab genotypes was 1.85% (13/703), which is very high in the Han Chinese population. The percentage of samples with diallelic patterns at DYS385ab was higher than that of monoallelic patterns (80.23% vs. 17.92%). Additionally, the percentage of samples with tetra-allelic patterns at DYS385ab was higher than that of tri-allelic patterns (1.28% vs. 0.43%), suggesting that there are possibly two copies with duplicated events happening frequently on the Y chromosome. Interestingly, the peak height of allele 13 was two to three-folds higher than that of other alleles. The allele 18 peak height was also two-fold higher than others, which could potentially be explained by a duplication event mechanism. We also found that tri-allelic genotypes for alleles 13, 17, and 20, tetra-allelic genotypes for alleles 13, 14, 19, and 20, and tetra-allelic genotypes for alleles 12, 13, 19 and 21 were more common than others. Furthermore, all 13 samples had multi-alleles containing allele 13, implying a founder effect in this particular Chinese-specific ethnic group. Taken together, this study provides new information for this population and will be useful for paternal lineage identification, kinship analysis, and family relationship reconstruction using Y-STR forensic DNA analysis methods. [ABSTRACT FROM AUTHOR]

An increasing number of US jurisdictions have begun to submit their previously untested sexual assault kits (SAKs) for DNA testing. However, best practices for what should happen after testing are not well established. Should all cases be investigated regardless of the testing outcome or only those that returned a DNA hit? We examine an early‐adopter jurisdiction that has completed testing and investigating all 5165 previously never tested kits. We explore and compare the criminal justice outcomes and cost‐effectiveness of investigating: all cases, those with CODIS hits, and those without CODIS hits. Findings indicate the SAK initiative produced a cost savings to the community: $26.48 million ($5127 p/kit) after the inclusion of tangible and intangible costs of future sexual assaults averted through convictions, of which $9.99 million ($1934 p/kit) was from also investigating no CODIS hit cases. When considering only the costs to law enforcement, investigating all cases cost $12,000 p/additional conviction. Findings also illustrate the cost‐effectiveness of investigating no CODIS hits cases and support an "investigate all" approach. This study enhances our understanding of the economic value of what comes after testing kits and investigating cases and provides a framework for jurisdictions for prioritizing resources and maximizing outcomes from testing. [ABSTRACT FROM AUTHOR]

Current analysis of forensic DNA stains relies on the probabilistic interpretation of bulk-processed samples that represent mixed profiles consisting of an unknown number of potentially partial representations of each contributor. Single-cell methods, in contrast, offer a solution to the forensic DNA mixture problem by incorporating a step that separates cells before extraction. A forensically relevant single-cell pipeline relies on efficient direct-to-PCR extractions that are compatible with standard downstream forensic reagents. Here we demonstrate the feasibility of implementing single-cell pipelines into the forensic process by exploring four metrics of electropherogram (EPG) signal quality—i.e., allele detection rates, peak heights, peak height ratios, and peak height balance across low- to high-molecular-weight short tandem repeat (STR) markers—obtained with four direct-to-PCR extraction treatments and a common post-PCR laboratory procedure. Each treatment was used to extract DNA from 102 single buccal cells, whereupon the amplification reagents were immediately added to the tube and the DNA was amplified/injected using post-PCR conditions known to elicit a limit of detection (LoD) of one DNA molecule. The results show that most cells, regardless of extraction treatment, rendered EPGs with at least a 50% true positive allele detection rate and that allele drop-out was not cell independent. Statistical tests demonstrated that extraction treatments significantly impacted all metrics of EPG quality, where the Arcturus® PicoPure™ extraction method resulted in the lowest median allele drop-out rate, highest median average peak height, highest median average peak height ratio, and least negative median values of EPG sloping for GlobalFiler™ STR loci amplified at half volume. We, therefore, conclude the feasibility of implementing single-cell pipelines for casework purposes and demonstrate that inferential systems assuming cell independence will not be appropriate in the probabilistic interpretation of a collection of single-cell EPGs. [ABSTRACT FROM AUTHOR]

Ramos and Gonzalez-Rodriguez introduce the concept of calibration in order to determine whether a system of evidence presentation is a reliable assessor of evidential weight. In this paper, we apply this calibration method to a dataset of mixed forensic DNA profiles generated using the QIAGEN Investigator® 24plex QS Kit and interpreted using the probabilistic genotyping software STRmix™.We describe the methodology for applying calibration to sets of forensic DNA profiles. We observe an approximate correspondence of the posterior probability, as assigned from the LR and the prior odds, with the observed rate of true donors for this dataset. [ABSTRACT FROM AUTHOR]

Featured Application: This paper's application of the proposed novel method is reducing the ski-slope effect in direct PCR, thus aiding more efficient amplification of DNA obtained from crime scenes. Analytical techniques such as DNA profiling are widely used in various fields, including forensic science, and novel technologies such as direct polymerase chain reaction (PCR) amplification are continuously being developed in order to acquire DNA profiles efficiently. However, non-specific amplification may occur depending on the quality of the crime scene evidence and amplification methods employed. In particular, the ski-slope effect observed in direct PCR amplification has led to inaccurate interpretations of the DNA profile results. In this study, we aimed to reduce the ski-slope effect by using dimethyl sulfoxide (DMSO) in direct PCR. We confirmed that DMSO (3.75%, v/v) increased the amplification yield of large-sized DNA sequences more than that of small-sized ones. Using 50 Korean buccal samples, we further demonstrated that DMSO reduced the ski-slope effect in direct PCR. These results suggest that the experimental method developed in this study is suitable for direct PCR and may help to successfully obtain DNA profiles from various types of evidence at crime scenes. [ABSTRACT FROM AUTHOR]

Y-chromosomal short tandem repeat (Y-STR) polymorphisms are useful in forensic identification, population genetics, and human structures. However, the current Y-STR systems are limited in discriminating distant relatives in a family with a low discrimination power. Increasing the capacity of detecting Y chromosomal polymorphisms will drastically narrow down the matching number of genealogy populations or pedigrees. In this study, we developed a system containing 17 Y-STRs that are complementary to the current commercially available Y-STR kits. This system was constructed by multiplex PCR with expected sizes of 126–400 bp labeled by different fluorescence molecules (DYS715, DYS709, DYS716, DYS713, and DYS607 labeled by FAM; DYS718, DYS723, DYS708, and DYS714 labeled by JOE; DYS712, DYS717, DYS721, and DYS605 labeled by TAMRA; and DYS719, DYS726, DYS598, and DYS722 labeled by ROX). The system was extensively tested for sensitivity, male specificity, species specificity, mixture, population genetics, and mutation rates following the Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines. The genetic data were obtained from eight populations with a total of 1260 individuals. Our results showed that all the 17 Y-STRs are human- and male-specific and include only one copy of the Y-chromosome. The 17 Y-STR system detects 143 alleles and has a high discrimination power (0.996031746). Mutation rates were different among the 17 Y-STRs, ranging from 0.30 to 3.03%. In conclusion, our study provides a robust, sensitive, and cost-effective genotyping method for human identification, which will be beneficial for narrowing the search scope when applied to genealogy searching with the Y-STR DNA databank. [ABSTRACT FROM AUTHOR]

In the past few years, cases with DNA evidence that could not be solved with direct matches in DNA databases have benefited from comparing single-nucleotide polymorphism data with private and public genomic databases. Using a combination of genome comparisons and traditional genealogical research, investigators can triangulate distant relatives to the contributor of DNA data from a crime scene, ultimately identifying perpetrators of violent crimes. This approach has also been successful in identifying unknown deceased persons and perpetrators of lesser crimes. Such advances are bringing into focus ethical questions on how much access to DNA databases should be granted to law enforcement and how best to empower public genome contributors with control over their data. The necessary policies will take time to develop but can be informed by reflection on the familial searching policies developed for searches of the federal DNA database and considerations of the anonymity and privacy interests of civilians. [ABSTRACT FROM AUTHOR]

The use of a fluorescent dye to visualize cellular material on surfaces offers a targeted sampling approach for locating touch DNA on casework items. However, the current application of such dye is not feasible for examination of relatively large items. As a result, development of an efficient dye application system is required to translate this approach into practice. Here, the spray pattern (area covered, intensity, and evenness) of 15 different commercial spray devices was examined visually using food coloring. From this, five devices were selected to apply Diamond Nucleic Acid Dye (DD) to three substrates (glass slide, plastic sheet, and brown packing tape) seeded with saliva and touch DNA. The cellular material was visualized using the Dino‐lite Microscope and Polilight. The inhibitory effects of DD afforded by each spray device were examined using Identifiler Plus® DNA profiling kit and a DNA input of 800 pg. The two most promising devices were further tested on a range of mock casework items seeded with touch DNA. The results presented demonstrate the feasibility of a spray system to apply DD to large surfaces and subsequently detect cellular material at both micro and macroscale. Specifically, the data suggest that a pressurized continuous‐spray system is favorable and that droplet size influences the intensity of fluorescence and surface coverage. Furthermore, this study indicates that full STR profiles can be obtained following spraying with DD solution, even with excessive application, which is essential for the widespread use of these devices in casework. [ABSTRACT FROM AUTHOR]

The advent of DNA profiling in the 1980s has revolutionised forensic science. Forensic DNA profiling is a powerful tool that is used to both exonerate and implicate persons of interest in criminal cases. The technologies used to recover and detect DNA from crime scene stains have evolved over time. Whereas 30 years ago most forensic profiles were generated from visible stains such as blood or semen, nowadays, DNA profiles are often generated from trace amounts of DNA including touched items. The DNA in these profiles is often compromised in quantity and quality, and frequently originates from more than one individual. This improved sensitivity has complicated the interpretation of forensic DNA profiles, and consequently improved methods of profile interpretation have had to be developed. The adoption of these methods has meant that forensic scientists can now interpret mixed DNA profiles previously thought to be too complicated. This article reviews the history of forensic DNA profiling globally, introduces the challenges of DNA profile interpretation, discusses why the community is adopting improved methods, and reflects on what new technology is on the horizon and the new challenges that may present. [ABSTRACT FROM AUTHOR]

The probabilistic genotyping software Forensic Statistical Tool implements a semi‐continuous model for DNA interpretation. This software omits any locus where the sum of the allele probabilities equals or exceeds.97. There has been criticism that this function is neither signaled by the software nor disclosed in publications. We investigate the effect of this function by creating a near clone of the model and applying it to five‐ and six‐allele loci for three‐person mixtures created in the expected population proportions. On average, the dropping of a locus is conservative for six‐peak loci and nonconservative for five‐peak loci. For persons of interest (POIs) with rare alleles, the dropping is usually conservative. For POIs with common alleles, the dropping of the locus is often nonconservative. This article is categorized under:Forensic Biology > Interpretation of Biological EvidenceForensic Biology > Forensic DNA TechnologiesJurisprudence and Regulatory Oversight > Expert Evidence and Narrative [ABSTRACT FROM AUTHOR]

There are three possible outcomes from drug therapy: the drug performs as intended; the drug has no effect; or the drug causes an adverse reaction. Variation in drug and endogenous toxin metabolism among individuals in part can be due to genetic makeup. The goal of pharmacogenetics is to elucidate the genetic variation contributing to absorption, distribution, metabolism, excretion, and response (ADME‐R) so that adverse drug reactions can be avoided, and to characterize differential enzyme activity informing appropriate drug dosage on the individual and population levels. The postmortem molecular autopsy may use pharmacogenetic information from a decedent to make conclusions about cause (CoD) and/or manner of death (MoD) when traditional medico‐legal autopsies are negative. The cytochrome p450 family is a group of pharmacogenetically relevant targets with demonstrable utility in the postmortem setting and several key historical applications. ATP‐binding cassettes and opioid receptors are additional critical drug response proteins with essential rolls in additive and suicidal behaviors and drug overdose. Historically, the discipline relied on genetic variation with large effects on a broad spectrum of endogenous and foreign compounds. However, recent advances in pharmacogenomics highlight rare variants and noncoding variation as strong contributing factors to the accuracy of drug response prediction. Furthermore, there is a push to develop more comprehensive predictive models incorporating both rare and common variants contributing to drug response. These advanced genetic capabilities will enable more accurate predictions of drug‐related CoD and/or MoD determinations and contribute to the growing overlap between medical and forensic genetics. This article is categorized under: Forensic Biology > Forensic DNA TechnologiesToxicology > OpioidsForensic Medicine > Methods for Certification of Cause and Manner of Death [ABSTRACT FROM AUTHOR]

As DNA technology becomes increasingly sensitive, forensic laboratories are receiving more low‐template DNA samples. These samples, already low in DNA content, become even more challenging to process as the available DNA becomes further reduced during the extraction step. In this study, two extraction modifications were tested to determine if the cause of DNA loss could be identified and mitigated. A double lysis technique was used to test for DNA loss in the sample collection substrate, and lysate eluates were re‐extracted to determine DNA loss from inefficient binding to the silica column. Both modifications showed DNA was lost at these steps. However, resulting STR profiles from these samples had fewer peaks and lower peak heights when compared to samples processed with no extraction modifications. Overall, the potential benefits of adding these extraction modifications for low‐template DNA sample processing are not enough to justify the risk associated with additional manipulation. [ABSTRACT FROM AUTHOR]

Insects have historically been used in criminal investigations to provide information in relation to postmortem intervals (PMIs) but the field of forensic entomology is expanding. It is now recognized that insects can act as vectors of human and mammalian DNA through the consumption of biological material, with extraneous DNA able to be extracted and genotyped from all stages of the life cycle, and insect feces and regurgitant (artifacts). To date, DNA recovered from insects have been used to inform investigations into neglect and homicide, link body parts, and to identify victims of crime. It may also potentially be used to identify assailants, confirm the food source of insects to determine their relevance in PMI calculations, determine if a crime has occurred, identify scenes of crimes, and link people to locations and other individuals. However, insects which have consumed biological material may also transfer DNA by traveling to new areas, or depositing it via their artifacts, either within crime scenes or laboratories, or at locations distant to the food source. This could contaminate forensic evidence, confound investigations, and/or falsely incriminate or exclude an individual. Therefore, it is important that there is increased awareness into both the utility of insects as vectors of forensically relevant DNA, and the potential for contamination. This article is categorized under:Forensic Biology > Forensic DNA TechnologiesForensic Science in Action/Crime Scene Investigation > Crime Scene ExaminationForensic Biology > Interpretation of Biological EvidenceForensic Biology > Body Fluid Identification [ABSTRACT FROM AUTHOR]

The ABO blood group is considered to be one of the most important markers in forensic testing. Additionally, autosomal short tandem repeat (STR) genotyping continues to be recognized as the dominant technique for determination of human identity, and Y chromosome STR (Y-STR) analysis is becoming increasingly important in solving criminal cases. In this paper, we describe an integrated amplification system of ABO, autosomal STR, and Y-STR genotyping in a single reaction. This system allows for the simultaneous detection of 18 autosomal STR loci (13 Combined DNA Index System [CODIS] loci, as well as D2S1338, D6S1043, D12S391, Penta D, and Penta E), the ABO blood group locus, the Y-STR locus DYS391, and the sex-determining amelogenin locus. Primers were designed and optimized for amplicon sizes from 80–420 bp using a five-dye fluorescent design with the fifth dye reserved for the internal size standard. Sensitivity assays resulted in successful amplification of genomic DNA in the range of 0.250–2.000 ng. A total of 90 individuals from the Chinese Han population were studied using the system and forensic genetic data are presented. We conclude that this integrated system could be an updated and improved solution for forensic DNA analysis. [ABSTRACT FROM AUTHOR]

Advancements in DNA sequencing technologies are occurring at a rapid rate. Various platforms have proven useful in all aspects of health and science research, from molecular diagnostics in cancer research to spore identifi cation in bioterrorism. In the fi eld of forensics, one particular single-molecule sequencing platform shows promise for becoming a viable solution for small to midsize forensic laboratories. Oxford Nanopore Technologies (ONT) has developed a portable, nanopore-based sequencing instrument that has already been utilized for on-site identifi cation of Zika and Ebola viruses, full genome sequencing, evaluation of DNA and RNA base modifi cations, and enrichment-free mitochondrial DNA analysis. The rapid development of this technology creates possibilities relevant to standard DNA sequencing, direct analysis of forensic samples, including blood, semen, and buccal swabs, mitochondrial DNA analysis, SNP and STR analysis, familial identifi cation, and microbial identifi cation for bioterrorism and geolocation. The small size of the platform, its low cost, and its requirement of only basic laboratory equipment makes this platform well suited for small laboratories wishing to begin developing expertise in sequence-based forensic analyses. Herein, we outline recent developments and applications of nanopore sequencing technologies and their potential application in forensic analysis. We address current and potential techniques in mitochondrial DNA analysis, SNP and STR typing, and microbial identifi cation. Additionally, we discuss recent developments in library preparation and data analysis tool further streamlining the sequencing process that integrate workfl ows in laboratories or in remote fi eld scenarios. [ABSTRACT FROM AUTHOR]

Back ground: It is important to establish STR database for future applications in forensic and paternity tests to gain a reliable evaluation for statistical analysis and that STR database would be more representative. Objective: The objectives of this study are establishing autosomal STR database for the population of Hilla City. Material and methods: DNA was extracted and purified from sixty six individuals from Hilla city by Prepfiller kit. Extracted DNA quantified by Quantifiler real time PCR kit. Fifteen autosomal STR loci (Identifiler) were amplified then analyzed by Genetic Analyzer. All kits supplemented by Applied Biosystem, USA. Results: All samples amplified and analyzed successfully. Allele frequency and forensic parameters were determined. Conclusion: We can conclude that we can use this database for further forensic and paternity applications. [ABSTRACT FROM AUTHOR]

In April 2018, the U.S. implemented a "zero-tolerance" immigration policy that would lead to the separation of more than 2,000 migrant families over the following months. By that summer, the policy and resultant family separations had generated a media storm that swept up the public. In early June, the government announced its consideration of DNA testing to aid in the detection of human trafficking in immigration contexts. Later that month, as the government retracted the child separation policy, the public began questioning how children and adults would be reunited and discussing the potential usefulness of DNA testing for those reunifications. Then in early July, the government announced that DNA testing was indeed being used, and by mid-month the public's outrage over the use of DNA was strong. We set out to examine the public dialogue on DNA testing—including misunderstandings and miscommunications—both in newspaper coverage and on Twitter in the 2-month summer period of 2018, at the height of public discussion of migrant family separations and then reunifications. We performed database searches identifying 263 newspaper articles and used Twitter's advanced search function identifying 153 Tweets containing discussion of the use of DNA for migrant family reunification. Upon the resulting sources, we performed content analysis, analyzing for slant on the immigration policy and the use of DNA tests using a combination of open and closed codes. Our analysis showed that perspectives on the use of DNA diverged in connection with perspectives on the immigration policy, and that there was a contrast among the cohorts in the stated utility of DNA testing. These findings offer insight into a) how DNA testing in a highly politicized immigration context was represented in media coverage and b) the public's understanding of the role that DNA testing could or should play in immigration. By detailing the role that comments from experts, stakeholders, and the public played in these discussions, we hope to provide lessons for communications with the public about future non-medical applications of genetic technologies. [ABSTRACT FROM AUTHOR]

In this study, we sought to document the efficiency of primer extension capture (PEC) as a method to enrich DNA eluates of targeted DNA molecules and remove nontarget molecules from pools containing both. Efficiency of the method was estimated by comparing number of "copies in" to "copies out" by quantitative polymerase chain reaction. PEC retention of DNA targets ranging 109‐288 base pairs (bps) in length was 15.88–2.14% (i.e., loss of 84.12–97.86% of target molecules). Experimental modifications of the PEC method resulted in no significant improvements. However, the benefit of PEC was revealed in its ability to remove most nontarget DNA molecules (99.99%). We also discovered that many (56.69%) of the target molecules are "lost" prior to their immobilization on the streptavidin‐coated beads. These estimates of methodological efficiency are directly comparable to previous ones observed following "fishing" for DNA, an alternative method for DNA enrichment. [ABSTRACT FROM AUTHOR]

Firearm-related exhibits are often found at crime scenes. These exhibits may include the firearm, cartridges, cartridges cases or bullets. As ammunition needs to be handled to load the weapon, regardless of the action or loading type, DNA may be deposited onto the ammunition via touch. As reproducible DNA profiles have been obtained from fired cartridge casings and Improvised Explosive Device (IED) fragments, it is possible that quantifiable amounts of DNA could be recovered from fired bullets. A series of 40 Winchester PowerPoint 22LR 42 grain HP Copper Plated bullets were loaded with serially diluted cell suspensions obtained from a female donor. These were shot into 500 sheet reams of A3 paper for capture and returned to a sterile DNA laboratory for removal, extraction and quantification of DNA. Repeatable partial profiles with five reportable loci pairs consistent with the cell donor were obtained in one replicate of the neat sample. Weak partial profiles were also present in 1:2, 1:5 and 1:10 dilutions. To our knowledge, this is the first reported evidence of DNA surviving the cycle of fire and being recovered from a fired bullet under controlled conditions. [ABSTRACT FROM AUTHOR]

Abstract: Piracatinga (Callophysius macropterus) are a type of bottom feeder catfish encountered in the Amazon River and its tributaries. We report two cases in which human remains were first located based on a characteristic circular distortion of the surface of the river that the Piracatinga make while they feed. Human skin samples of one of the victims recovered from the Piracatinga digestive tract were subjected to mitochondrial DNA analysis that allowed identification of the body of Case 1; the family recognized body parts of Case 2. Importantly, the location of human body parts and their identification based on DNA analysis enabled the respective families to obtain a death certificate expeditiously in the absence of identifiable remains—a process that normally requires 5 years under current Brazilian law, and in the absence of closure, imposes severe emotional stress on the family of the deceased. [ABSTRACT FROM AUTHOR]

Bloodstains are extremely important forensic evidence for DNA profiling. The current study has been planned to quantify DNA recovery from a list of fabrics tested after washing. On each fabric, spots of blood was dotted, and the dried-bloodstained fabrics were hand washed with tap water, soaked in tap water with detergent and then hand washed, for 5 and 10 min. DNA was extracted through Chelex100 from these fabrics and quantified through Real Time PCR using the Quantifiler Human DNA Quantification kit. Results showed that DNA can be recovered from fabrics after they have been washed. The amount of recovered DNA is comparable among these fabrics and did not show significant variations with washing methods. Blends of fabrics showed the highest recovery while non-absorbent fabrics showed least DNA recovery. Knowledge of the different DNA quantities recovered from washed fabrics will be useful in solving criminal cases. The ability to recover DNA from washed fabrics could prove important in forensic casework. [ABSTRACT FROM AUTHOR]

Abstract: Motivated by the debate over how to deal with the huge backlog of untested sexual assault kits in the U.S.A., we construct and analyze a mathematical model that predicts the expected number of hits (i.e., a new DNA profile matches a DNA sample in the criminal database) as a function of both the proportion of the backlog that is tested and whether the victim–offender relationship is used to prioritize the kits that are tested. Refining the results in Ref. (Criminol Public Policy, 2016, 15, 555), we use data from Detroit, where government funding was used to process ≈15% of their backlog, to predict that prioritizing stranger kits over nonstranger kits leads to only a small improvement in performance (a 0.034 increase in the normalized area under the curve of the hits vs. proportion of backlog tested curve). Two rough but conservative cost‐benefit analyses—one for testing the entire backlog and a marginal one for testing kits from nonstranger assaults—suggest that testing all sexual assault kits in the backlog is quite cost‐effective: for example, spending ≈$1641 to test a kit averts sexual assaults costing ≈$133,484 on average. [ABSTRACT FROM AUTHOR]

In 1984, a group of Argentine students, trained by US academics, formed the Argentine Forensic Anthropology Team to apply the latest scientific techniques to the excavation of mass graves and identification of the dead, and to work toward transitional justice. This inaugurated a new era in global forensic science, as groups of scientists in the Global South worked outside of and often against local governments to document war crimes in post-conflict settings. After 2001, however, with the inauguration of the war on terror following the September 11th attacks on the World Trade Center in New York, global forensic science was again remade through US and European investment to increase preparedness in the face of potential terrorist attacks. In this paper, I trace this shift from human rights to humanitarian forensics through a focus on three moments in the history of post-conflict identification science. Through a close attention to the material semiotic networks of forensic science in post-conflict settings, I examine the shifting ground between non-governmental human rights forensics and an emerging security- and disaster-focused identification grounded in global law enforcement. I argue that these transformations are aligned with a scientific shift towards mechanized, routinized, and corporate-owned DNA identification and a legal privileging of the right to truth circumscribed by narrow articulations of kinship and the body. [ABSTRACT FROM AUTHOR]

Combining genotypes across datasets is central in facilitating advances in genetics. Data aggregation efforts often face the challenge of record matching-the identification of dataset entries that represent the same individual. We show that records can be matched across genotype datasets that have no shared markers based on linkage disequilibrium between loci appearing in different datasets. Using two datasets for the same 872 people-one with 642,563 genome-wide SNPs and the other with 13 short tandem repeats (STRs) used in forensic applications-we find that 90-98% of forensic STR records can be connected to corresponding SNP records and vice versa. Accuracy increases to 99-100%when ∼30 STRs are used. Our method expands the potential of data aggregation, but it also suggests privacy risks intrinsic in maintenance of databases containing even small numbers of markers-including databases of forensic significance. [ABSTRACT FROM AUTHOR]

Formalin fixation is commonly used to preserve tissue sections for pathological testing and embalming cadavers for medical dissection or burial. DNA extracted from formalin-fixed tissues may also provide an alternative source of genetic material for medical diagnosis and forensic casework, such as identifying unknown embalmed human remains. Formaldehyde causes DNA damage, chemical modifications, and degradation, thereby reducing the quantity and quality of DNA available for downstream genetic analyses. By comparing the DNA yield, level of DNA degradation, and short tandem repeat (STR) success of various tissue types, this study is the first of its kind to provide some guidance on which samples from embalmed bodies are likely to generate more complete STR profiles. Tissue samples were dissected from three male embalmed cadavers and included bone, cartilage, hair, muscle, internal organs, skin, teeth, and nail clippings. DNA was purified from all samples using the QIAamp® FFPE Tissue Kit (Qiagen), quantified using the QuantiFiler ® Trio DNA Quantification kit (Life Technologies), and genotyped using the GlobalFiler ® PCR Amplification Kit (Life Technologies). Results of this study showed variation in DNA quantity and STR success between different types of tissues and some variation between cadavers. Overall, bone marrow samples resulted in the highest DNA yields, the least DNA degradation, and greatest STR success. However, several muscle, hair, and nail samples generated higher STR success rates than traditionally harvested bone and tooth samples. A key advantage to preferentially using these tissue samples over bone (and marrow) and teeth is their comparative ease and speed of collection from the cadaver and processing during DNA extraction. Results also indicate that soft tissues affected by lividity (blood pooling) may experience greater exposure to formalin, resulting in more DNA damage and reduced downstream STR success than tissues under compression. Overall, we recommend harvesting from selected muscles (gastrocnemius, rectus femoris, flexor digitorum brevis, masseter, brachioradialis) or fingernails for human identification purposes. [ABSTRACT FROM AUTHOR]

In 1984, eight-year-old Paula Logares was called into a judge’s chambers and was told the man and woman she lived with were not her parents. Her parents had been disappeared during the dirty war, and now, through her blood, scientists would be able to return her to her birth family. Paula, thus, became the first “stolen” child in Argentina to be identified via the incipient technology of DNA identification. With this forensic first, DNA identification has emerged as a central tool of good governance the world round. From routine crime fighting to international criminal tribunals, DNA plays a crucial role in attempts to reckon with crimes of the body. As an alternative origin for forensic DNA, Argentina offers an early example of science emerging from social movements in the Global South. Drawing on twenty-seven months of fieldwork with family members, activists, and scientists, this article documents the ways in which DNA has emerged as a core site of subject formation for individuals and families affected by the terror of the dictatorship and for the Argentine nation-state, as it reckons with the legacies of repression. Through a feminist, postcolonial frame, I offer the concept of re(con)stitution as a way of attending to the forms of biocitizenship that emerge during times of humanitarian crisis and transitional justice. As a tool of reproductive governance, forensic DNA acts not only as a powerful disciplinary site of biocitizenship but also as a potential space to reimagine the social contract between the body, the public, and the state. [ABSTRACT FROM AUTHOR]

A new phenomenon was detected using the Applied Biosystems 3500xL Genetic Analyzer. This phenomenon is characterised by a strong sample in an injection imparting low-level peaks to negative control samples positioned anywhere within the same injection. The affected negative controls did not display these peaks when processed in the absence of the strong sample. This phenomenon, hereafter described as ‘signal interference’, has been demonstrated to be an extension of the widely accepted capillary electrophoresis anomaly known as ‘crosstalk’. Signal interference has been observed in casework profile analysis and the potential implications for casework are discussed. [ABSTRACT FROM PUBLISHER]