Ethical challenges of merging criminal identification and civil identification within the Prüm system

The so-called Prüm system made mandatory for all EU Member States to join the pan-European network for the exchange of fingerprints, DNA profiles and motor vehicle information for stepping up on cross-border cooperation, particularly in combating terrorism and cross-border crime. Taking into consideration the number of DNA profiles archived in the national databases of the operational countries, more than 13 million DNA profiles can potentially be exchanged. Plans for “next-generation Prüm” that may soon be introduced aim to exchange additional forensic modalities, namely facial recognition data (FRD). This commentary highlights the ethical and social problems of merging DNA profiles of convicted persons, suspects and crime stains (targeting criminal identification) with DNA profiles from missing persons, relatives of missing persons, unidentified persons and unidentified human remains (oriented to civil identification). In a complementary manner, we also discuss the problematic amendments of the so-called “next-generation Prüm” that may soon be introduced that includes plans to exchange additional forensic modalities, namely facial recognition data (FRD).     

Inference of recent admixture using genotype data

The inference of biogeographic ancestry (BGA) has become a focus of forensic genetics. Misinference of BGA can have profound unwanted consequences for investigations and society. We show that recent admixture can lead to misclassification and erroneous inference of ancestry proportions, using state of the art analysis tools with (i) simulations, (ii) 1000 genomes project data, and (iii) two individuals analyzed using the ForenSeq DNA Signature Prep Kit. Subsequently, we extend existing tools for estimation of individual ancestry (IA) by allowing for different IA in both parents, leading to estimates of parental individual ancestry (PIA), and a statistical test for recent admixture. Estimation of PIA outperforms IA in most scenarios of recent admixture. Furthermore, additional information about parental ancestry can be acquired with PIA that may guide casework.     

Using a multi-head,convolutional neural network with data augmentation to improve electropherogram classification performance

DNA profiles are generated in forensic biology laboratories around the world. It is possible that these profiles are assessed by two independent people in order for the profiles to be ‘read’. Recent work has been carried out to develop a neural network model to classify fluorescence in a DNA profile electropherogram and potentially replace one, or both human readers. The ability to use neural networks for this function has been programmed into the software FaSTR™ DNA, which has been validated for use in at least one laboratory in Australia. The work that previously developed a neural network system had a number of limitations, specifically it was computer intensive, did not make the best use of available data, and consequently the performance of this model was sub-optimal in some conditions (particularly for low-intensity peaks). In the current work a new neural network model is developed that makes various improvements on the old model, by using convolutional layers, a multi-head architecture and data augmentation. Results indicate that an improved performance can be expected for low-intensity profiles.     

A novel method to estimate adult age from the lumbar vertebral body using 3D PMCT images in Japanese

This study evaluated the age-related changes in the vertebral body using 3D Postmortem CT (PMCT) images and proposed an alternative age estimation formula. The PMCT images of 200 deceased individuals aged 25 to 99 years (126 males, 74 females) were retrospectively reviewed and included in the study. Using the open-source software ITK-SNAP and MeshLab, a 3D surface mesh of the fourth lumbar vertebral body (L4) and its convex hull models were created from the PMCT data. Using their inbuilt tools, volumes (in mm3) of the L4 surface mesh and convex hull models were subsequently computed. We derived VD, defined as the difference in volumes between the convex hull and L4 surface mesh normalized by L4 mesh volume, and VR, defined as the ratio of L4 mesh volume to convex hull volume based on individual L4. Correlation and regression analyses were performed between VD, VR, and chronological age. A statistically significant positive correlation (P < 0.001) between chronological age and VD, (r_s = 0.764, males; r_s = 0.725, females), and a significant negative correlation between chronological age and VR (r_s = -0.764, males; r_s = -0.725, females) was obtained in both sexes. The lowest standard error of the estimate was demonstrated by the VR at 11.9 years and 12.5 years for males and females, respectively. As such, their regression models to estimate adult age were Age = 248.9–2.5VR years, males; Age = 258.1–2.5VR years, females. These regression equations may be useful for estimating age in Japanese adults in forensic settings.     

A new strategy for distinguishing menstrual blood from peripheral blood by the miR-451a/miR-21-5p ratio

Distinction between menstrual blood and peripheral blood is vital for forensic casework, as it could provide strong evidence to figure out the nature of some criminal cases. However, to date no single blood-specific gene, including the most variable microRNAs (miRNAs) could work well in identification of blood source. In this study, we developed a new strategy for identification of human blood samples by using the copy number ratios of miR-451a to miR-21–5p based on 133 samples, including 56 menstrual blood and 47 peripheral blood, as well as 30 non-blood samples of saliva (10), semen (10) and vaginal secretion (10). The cut-off value and efficacy of the identification strategy were determined through receiver operating characteristic (ROC) analysis. Our results showed that when the miR-451a/miR-21–5p ratio below 0.929, the sample should be non-blood. In contrast, when the miR-451a/miR-21–5p ratio above 0.929 and below 10.201, the sample should be menstrual blood; and when this ratio above 10.201, the sample should be peripheral blood. External validation using 86 samples (62 menstrual blood and 24 peripheral blood samples) fully supported this strategy with the 100% sensitivity and 100% specificity. We confirmed that this result accuracy was not affected by various potential confounding factors of samples and different experimental platforms. We showed that 0.2 ng of total RNA from menstrual blood and peripheral blood was sufficient for qPCR quantification. In conclusion, our results provide an accurate reference to distinguish menstrual blood from peripheral blood for forensic authentication.     

Young offenders in forensic institutions in the Netherlands after committing serious crimes: Contribution of mandatory treatment and reduction of reincarceration

Background

In the Netherlands, young offenders who have been convicted of a particularly serious offence may be subjected to a so-called ‘Placement in an Institution for Juveniles’ (PIJ) measure if they are considered to pose a high ongoing risk to public safety. They form a rarely studied distinct group. Treatment in specialist forensic custodial institutions for young people (FYCI) is an intervention of last resort and costly. The most serious young offenders tend to be the hardest to rehabilitate while preventing further offending. Treatment is focussed on reducing risk of harm as well as improving health and other protective factors.

Aims

To explore the contribution of treatment in an FYCI under a forensic treatment order—the PIJ-measure—to the reduction of risk of reoffending.

Methods

In a pre–post intervention study, the Juvenile Forensic Profile (JFP) was used to score complete case files of 178 young offenders at the start and end of their placement in an FYCI under the PIJ-measure, 59% of those serving between the years 2013 and 2016 inclusive. The JFP covers risk and protective factors in seven domains encompassing criminal behaviour, family, environment, risk factors, psychopathology, psychology and behaviour during incarceration. Change or stability in scores was tested against reincarceration within 2 years of PIJ-measure completion.

Results

Impulse control and alcohol and drug use problems showed the greatest improvements. Behaviour that deteriorates during the stay is primarily related to obtaining more autonomy during reintegration efforts, including furlough. Reincarceration in the 2 years of community follow-up was unusual (13.5%). The two main variables associated with reincarceration were problematic behaviour during the pre-discharge year and lack of behavioural improvement during treatment.

Conclusions

Outcomes of mandatory treatment in this group of serious young offenders have not previously been studied in a rigorous pre–post intervention study design. We found evidence of an overall tendency to improvement over time in mental state and social skills, reflected by risk assessment scale scores. Continued substance use problems while incarcerated and continuing social skills deficits were most strongly associated with reincarceration suggests a possible need for review of these areas in the PIJ-measure programme. Results contribute to knowledge about risk assessment, treatment and preventions of harms by serious young offenders and may inform evidence-based policies and practices in the Netherlands and beyond.

     

Assessment of the ForenSeq mtDNA control region kit and comparison of orthogonal technologies

The ForenSeq® mtDNA Control Region Kit, MiSeq FGx®, and Universal Analysis Software (UAS) were assessed to better define the performance and limitations of the system with forensically relevant samples to provide data for its transition into practice. A total of six MiSeq FGx sequencing runs of ForenSeq mtDNA Control Region kit, three runs of additional orthogonal sequencing chemistries, and Sanger sequencing results for 14 samples were used to test for concordance. Sensitivity, reproducibility, mixture detection studies, as well as studies to measure the performance of amplification and sequencing controls were performed. The use and reliability of the UAS for data analysis was also examined. With a variety of sample types and controls representing many mitochondrial haplotypes, the recently developed mtDNA Control Region Kit, with the MiSeq FGx and UAS, was found to be fit for purpose as reliable, reproducible, and robust. Sensitivity down to 1 pg of input genomic DNA was demonstrated, which allows the system to offer low limits of detection for better interrogation of potential heteroplasmy in samples. Concerns for implementing next generation sequencing (NGS) for mtDNA in laboratories were addressed in this research, including initial template quantification and confirmation of haplotypes generated by UAS software regarding length-based polymorphisms. To improve performance with forensic samples, laboratories could implement mitochondrial-specific qPCR assays for quantification and perform the optional manual normalization protocol. Additional optimization on sample multiplexing can provide methods that either increase sensitivity or cost efficiency of the assay.     

Development and validation of a fast and automated DNA identification line

The importance of DNA evidence for gaining investigative leads demands a fast workflow for forensic DNA profiling performed in large volumes. Therefore, we developed software solutions for automated DNA profile analysis, contamination check, major donor inference, DNA database (DDB) comparison and reporting of the conclusions. This represents the Fast DNA IDentification Line (FIDL) and this study describes its development, validation and implementation in criminal casework at the authors’ institute. This first implementation regards single donor profiles and major contributors to mixtures. The validation included testing of the software components on their own and examination of the performance of different DDB search strategies. Furthermore, end-to-end testing was performed under three conditions: (1) testing of scenarios that can occur in DNA casework practice, (2) tests using three months of previous casework data, and (3) testing in a casework production environment in parallel to standard casework practices. The same DNA database candidates were retrieved by this automated line as by the manual workflow. The data flow was correct, results were reproducible and robust, results requiring manual analysis were correctly flagged, and reported results were as expected. Overall, we found FIDL valid for use in casework practice in our institute. The results from FIDL are automatically reported within three working days from receiving the trace sample. This includes the time needed for registration of the case, DNA extraction, quantification, polymerase chain reaction and capillary electrophoresis. FIDL itself takes less than two hours from intake of the raw CE data to reporting. Reported conclusions are one of five options: (1) candidate retrieved from DDB, (2) no candidate retrieved from DDB, (3) high evidential value with regards to reference within the case, (4) results require examination of expert, or (5) insufficient amount of DNA obtained to generate a DNA profile. In our current process, the automated report is sent within three working days and a complete report, with confirmation of the FIDL results, and signed by a reporting officer is sent at a later time. The signed report may include additional analyses regarding e.g. minor contributors. The automated report with first case results is quickly available to the police enabling them to act upon the DNA results prior to receiving the full DNA report. This line enables a uniform and efficient manner of handling large numbers of traces and cases and provides high value investigative leads in the early stages of the investigation.