Current and future directions of DNA in wildlife forensic science

Mitochondrial Control Region Database of Hungarian Fallow Deer (Dama dama) Populations for Forensic Use

The evidential value of an mtDNA match between biological remains and their potential donor is determined by the random match probability of the haplotype. This probability is based on the haplotype's population frequency estimate. Consequently, implementing a population study representative of the population relevant to a forensic case is vital to correctly evaluating the evidence. The emerging number of poaching cases and the limited availability of such data emphasizes the need for an improved fallow deer mtDNA population databank for forensic purposes, including targeting the entire mitochondrial control region. By sequencing a 945-base-pair-long segment of the mitochondrial control region in 138 animals from five populations in Hungary, we found four different haplotypes, including one which had not yet been described. Our results, supplemented with data already available from previous research, do not support the possibility of determining the population of origin, although some patterns of geographical separation can be distinguished. Estimates of molecular diversity indicate similarly low mtDNA diversity (Hd = 0.565 and π = 0.002) compared to data from other countries. The calculated random match probability of 0.547 shows a high probability of coincidence and, therefore, a limited capacity for exclusion. Our results indicate that despite the overall low genetic diversity of mtDNA within the Hungarian fallow deer samples, a pattern of differentiation among the regions is present, which can have relevance from a forensic point of view.

Barcoding Brazilian mammals to monitor biological diversity and threats: Trends, perspectives, and knowledge gaps

DNA barcoding and environmental DNA (eDNA) represent significant advances for biomonitoring the world's biodiversity and its threats. However, these methods are highly dependent on the presence of species sequences on molecular databases. Brazil is one of the world's largest and most biologically diverse countries. However, many knowledge gaps still exist for describing, identifying, and monitoring of mammalian biodiversity using molecular methods. We aimed to unravel the patterns of the presence of Brazilian mammal species on molecular databases to improve our understanding of how effectively it would be to monitor them using DNA barcoding and environmental DNA, and contribute to mammalian conservation. We foundt many gaps in molecular databases, with many taxa being poorly represented, particularly from Amazonia, the order Lagomorpha, and arboreal, gomivorous, near extinct, and illegally traded species. Moreover, our analyses revealed that species description year was the most important factor determining the probability of a species to being sequenced. Primates are the group with the highest number of species considered a priority for sequencing due to their high level of combined threats. We highlight where investments are needed to fill knowledge gaps and increase the representativity of species on molecular databases to enable a better monitoring ability of Brazilian mammals encompassing different traits using DNA barcoding and environmental DNA.

Mitochondrial genome structure and composition in 70 fishes: a key resource for fisheries management in the South Atlantic

BACKGROUND

Phylogenetic gaps of public databases of reference sequences are a major obstacle for comparative genomics and management of marine resources, particularly in the Global South, where economically important fisheries and conservation flagship species often lack closely-related references. We applied target-enrichment to obtain complete mitochondrial genomes of marine ichthyofauna from the Brazilian coast selected based on economic significance, conservation status and lack of phylogenetically-close references. These included sardines (Dorosomatidae, Alosidae), mackerels (Scombridae) croakers (Sciaenidae), groupers (Epinephelidae) and snappers (Lutjanidae).

RESULTS

Custom baits were designed to enrich mitochondrial DNA across a broad phylogenetic range of fishes. Sequencing generated approximately 100k reads per sample, which were assembled in a total of 70 complete mitochondrial genomes and include fifty-two new additions to GenBank, including five species with no previous mitochondrial data. Departures from the typical gene content and order occurred in only three taxa and mostly involved tRNA gene duplications. Start-codons for all genes, except Cytochrome C Oxidase subunit I (COI), were consistently ATG, whilst a wide range of stop-codons deviated from the prevailing TAA. Phylogenetic analysis confirmed assembly accuracy and revealed signs of cryptic diversification within the Mullus genus. Lineage delimitation methods using Sardinella aurita and S. brasiliensis mitochondrial genomes support a single Operational Taxonomic Unit.

CONCLUSIONS

Target enrichment was highly efficient, providing complete novel mitochondrial genomes with little sequencing effort. These sequences are deposited in public databases to enable subsequent studies in population genetics and adaptation of Latin American fish species and serve as a vital resource for conservation and management programs that rely on molecular data for species and genus-level identification.

Visualisation and detection of latent DNA deposited by pangolin scales onto plastic packaging materials

We report on the detection and visualisation of latent DNA from pangolin scales deposited onto a plastic packaging material through the use of a nucleic acid staining dye. This latent DNA deposited by pangolin scales was subsequently isolated and analysed using DNA barcoding method. Pangolins are the most illegally traded mammalian species due to the demand for their scales and meat. The demand for their scales were mostly fuelled by its use in traditional medicines. The scales are usually packed into bags and transported globally via sea routes. This is the first report detailing the detection of trace latent DNA from processed wildlife products, on surfaces of bags that they were packaged in. Prior to this report, it was not known if the dried pangolin scales contained transferable quantities of biological material for DNA analyses. To address this, scales were removed from a roadkill Sunda pangolin (Manis javanica), processed by drying and packaged into one of five plastic bags. The presence of pangolin latent DNA was detected on the surface of the plastic bags and visualised using Diamond™ nucleic acid dye. Swabs were then used to recover the stained biological material from various locations in the five bags. The DNA was isolated and quantified using a newly designed quantitative PCR (qPCR) specific to M. javanica to amplify a fragment of the mitochondrial DNA cytochrome b gene. There was a positive correlation between the number of stained particles and DNA quantity, and a greater number of stained particles were found at the bottom of the bag than were found at the top. Conventional PCR targeting part of the cyt b gene amplified a product from all 30 samples taken from the bags and in all cases, sequence data generated matched that of the Sunda pangolin, as expected. All negative controls yielded no results. The method described here is the very first use of a nucleic acid staining dye to detect latent DNA from a mammalian species, other than humans, and highlights the opportunity for further use of Diamond™ nucleic acid dye in wildlife forensic science. It is anticipated that this method will be invaluable in retrieving latent DNA deposited by wildlife products from the environment in which they were contained, to determine the presence of these illegal wildlife products even when previously hidden, inaccessible, or no longer present physically. Further research is required to understand if the use on non-human mammalian wildlife species is feasible.

A multilocus DNA mini-barcode assay to identify twenty vertebrate wildlife species

The world faces significant challenges in preserving the diversity of vertebrate species due to wildlife crimes. DNA barcoding, an effective molecular marker for insufficient nuclear DNA, is an authentic and quick identification technique to trace the origin of seized samples in forensic investigations. Here, we present a multiplex assay capable of identifying twenty vertebrate wildlife species utilizing twenty species-specific primers that target short fragments of the mitochondrial Cyt b, COI, 16S rRNA, and 12S rRNA genes. The assay achieved strong species specificity and sensitivity with a detection limit as low as 5 pg of DNA input. Additionally, it effectively discriminated a minor contributor (≥1%) from binary mixtures and successfully identified of noninvasive samples, inhibited DNA samples, artificially degraded DNA samples, and case samples, demonstrating a sensitive, robust, practical and easily interpretable tool in screening, and investigating forensic wildlife crimes.

Development of specific and rapid detection of human DNA by recombinase polymerase amplification assay for forensic analysis

The determination of human-derived samples is very important in forensic investigations and case investigation in order to determine vital information on the suspect and the case. In this study, we established a recombinase polymerase amplification (RPA) assay for rapid identification of human-derived components. The sensitivity of the assay was 0.003125 ng, with excellent species specificity, and human-derived DNA could be detected in the presence of non-human-derived components at a ratio of 1:1000. Moreover, the RPA assay had a strong tolerance to inhibitors, in the presence of 800 ng/μL humic acid, 400 ng/μL tannic acid, and 8000 ng/μL collagen. In forensic investigation, common body fluids (blood, saliva, semen, vaginal secretions) are all applicable, and the presence of DNA can be detected from samples after simple alkaline lysis, which greatly shortens the detection time. Four simulation and case samples (aged bones, aged bloodstains, hair, touch DNA) were also successfully applied. The above research results show that the RPA assay constructed in this study can be fully applied to forensic medicine to provide high sensitivity and applicability detection methods.

The Revolution of Animal Genomics in Forensic Sciences

Nowadays, the coexistence between humans and domestic animals (especially dogs and cats) has become a common scenario of daily life. Consequently, during a forensic investigation in civil or criminal cases, the biological material from a domestic animal could be considered "evidence" by law enforcement agencies. Animal genomics offers an important contribution in attacks and episodes of property destruction or in a crime scene where the non-human biological material is linked to the victim or perpetrator. However, only a few animal genetics laboratories in the world are able to carry out a valid forensic analysis, adhering to standards and guidelines that ensure the admissibility of data before a court of law. Today, forensic sciences focus on animal genetics considering all domestic species through the analysis of STRs (short tandem repeats) and autosomal and mitochondrial DNA SNPs (single nucleotide polymorphisms). However, the application of these molecular markers to wildlife seems to have gradually gained a strong relevance, aiming to tackle illegal traffic, avoid the loss of biodiversity, and protect endangered species. The development of third-generation sequencing technologies has glimmered new possibilities by bringing "the laboratory into the field", with a reduction of both the enormous cost management of samples and the degradation of the biological material.

Poaching Forensics: Animal Victims in the Courtroom

Poaching and the international trade in wildlife are escalating problems driven by poverty and greed and coordinated by increasingly sophisticated criminal networks. Biodiversity loss, caused by habitat change, is exacerbated by poaching, and species globally are facing extinction. Forensic evidence underpins human and animal criminal investigations and is critical in criminal prosecution and conviction. The application of forensic tools, particularly forensic genetics, to animal case work continues to advance, providing the systems to confront the challenges of wildlife investigations. This article discusses some of these tools, their development, and implementations, as well as recent advances. Examples of cases are provided in which forensic evidence played a key role in obtaining convictions, thus laying the foundation for the future application of techniques to disrupt the criminal networks and safeguard biodiversity through species protection.

A forensically validated genetic toolkit for the species and lineage identification of the highly trafficked shingleback lizard (Tiliqua rugosa)

Shingleback lizards (Tiliqua rugosa) are among the most trafficked native fauna from Australia in the illegal pet trade. There are four morphologically recognised subspecies of shinglebacks, all with differing overseas market values. Shinglebacks from different geographic locales are often trafficked and housed together, which may complicate identifying the State jurisdiction where the poaching event occurred. Additionally, shinglebacks can be housed and trafficked with other species within the same genus, which may complicate DNA analysis, especially in scenarios where indirect evidence (e.g. swabs, faeces) is taken for analysis. In this study, a forensic genetic toolkit was designed and validated to target shingleback DNA for species identification and geographic origin. To do this, field sampling across Australia was conducted to expand the phylogeographic sampling of shinglebacks across their species range and include populations suspected to be poaching hotspots. A commonly used universal reptile primer set (ND4/LEU) was then validated for use in forensic casework related to the genus Tiliqua. Two additional ND4 primer sets were designed and validated. The first primer set was designed and demonstrated to preferentially amplify an ∼510 bp region of the genus Tiliqua over other reptiles and builds on existing data to expand the available phylogeographic database. The second primer set was designed and demonstrated to solely amplify an ∼220 bp region of T. rugosa ND4 over any other reptile species. Through the validation process, all primers were demonstrated to amplify T. rugosa DNA from a variety of sample types (e.g. degraded, low quality and mixed). Two of the primer sets were able to distinguish the genetic lineage of T. rugosa from the phylogeographic database. This work provides the first forensically validated toolkit and phylogeographic genetic database for Squatmate lizards.

Unraveling the mystery of confiscated "jackal horns" in India using wildlife forensic tools

Internationally, illegal wildlife trade involves highly prized and charismatic species and their derivatives. At the same time, common or less known species and their parts are also encountered but receive less attention than charismatic species. Given the increasing demand for wildlife products in many parts of the world, profit, and short supply, many fake articles derived from domestic or wild animals are frequently encountered in the wildlife trade. Jackal horn (locally known as "Siyar or Gidar singhi") is one such fake item widely used in sorcery and other occult practices available through offline and online trading platforms within India. We used a combination of morphological, microscopic hair, and molecular approaches (Cyt b and 16 s rRNA genes) to reveal the true identity of confiscated "jackal horns" (n = 342). Detailed morphological study of the jackal horns showed that it varied in size, shape, color of hair, attachment material, and filling material. The microscopic hair and molecular approaches revealed that all the items sold as jackal horns were fake and made up of protected wild species and domestic animals. Our results confirm the use of the biological samples from few wild species protected under the Wild Life (Protection) Act, 1972, of India. Therefore, the law enforcement agencies are cautioned to get forensic opinions while dealing with such counterfeit items.

Molecular Sexing and Species Detection of Antlered European Hunting Game for Forensic Purposes

Simple Summary

The reasons behind illegal hunting can be widely different. There are also tricky methods that hunters use in the attempt to legalize their illegally-acquired trophies, specifically, introducing them in later seasons, and registering the eviscerated corpses as hinds. During certain periods of the year, hunters are only able to acquire a license for the shooting of female deer exclusively, with the male-hunting season beginning later. The eviscerated and decapitated carcass of the animal delivered to the wild game processing house cold store can be falsely registered as a female based on phenotype. If the hunting association suspects that the animal’s sex has been falsely reported, a forensic genetic investigation can be proposed. In other criminal events, there are no carcasses at all. When several biological remains left on the crime scene need to be tested, a fast and cost-effective detection of a given species or species-group might be substantial before subsequent analysis. Therefore, sex and species detection can provide an early-stage credibility to the resolution of illegal activities related to trophy animals, and additionally may disclose potential poaching disputes.

Abstract

Molecular sexing techniques are widely applied in conservation biology, although the range of forensically validated methods is fairly limited. The primary aim of this work was to develop forensically validated assays, using two PCR panels for sex and species assignment for the abundant antlered European game species: red deer (Cervus elaphus), roe deer (Capreolus capreolus) and fallow deer (Dama dama). Segments of the SRY and Amelogenin X/Y genes for sex determination, additionally species-specific cytochrome b regions for species detection were targeted and separately amplified in two multiplex reactions. These assays can reliably analyze trace amounts of DNA. The results of both can easily be visualized and interpreted practically, either on agarose gel or by capillary electrophoresis. These simple, fast molecular assays are able to affect the early-stage resolution of disputed or unsolved poaching cases, without the need of individualization or sequencing of forensic samples.

Development and validation of simultaneous identification of 26 mammalian and poultry species by a multiplex assay

A multiplex PCR assay was developed to simultaneously identify 22 mammalian species (alpaca, Asiatic black bear, Bactrian camel, brown rat, cat, cattle, common raccoon, dog, European rabbit, goat, horse, house mouse, human, Japanese badger, Japanese wild boar, masked palm civet, pig, raccoon dog, red fox, sheep, Siberian weasel, and sika deer) and four poultry species (chicken, domestic turkey, Japanese quail, and mallard), even from a biological sample containing a DNA mixture of multiple species. The assay was designed to identify species through multiplex PCR and capillary electrophoresis, with a combination of amplification of a partial region of the mitochondrial D-loop by universal primer sets and a partial region of the cytochrome b (cyt b) gene by species-specific primer sets. The assay was highly sensitive, with a detection limit of 100 copies of mitochondrial DNA. The assay's ability to identify species from complex DNA mixtures was demonstrated using an experimental sample consisting of 10 species. Efficacy, accuracy, and reliability of the assay were validated for use in forensic analysis with the guidelines of Scientific Working Group on DNA Analysis Methods (SWGDAM). The multiplex PCR assay developed in this study enables cost-effective, highly sensitive, and simultaneous species identification without massively parallel sequencing (MPS) platforms. Thus, the technique described is straightforward and suitable for routine forensic investigations.

Scales of our lives: Sex identification of Temminck's pangolin (Smutsia temminckii) using scales retrieved out of the illegal wildlife trade

Pangolins are the most trafficked wild mammals, with their scales in high demand. Scales are often the only part of the animal confiscated from the trade, but they represent accessible material for forensic investigations, including for sexing. This study aimed to develop a sexing tool for Temminck's pangolin, using scales for hormone quantification. Scales from males and females were liquidised using keratinase and the resulting suspension analysed for progestagen and androgen metabolite (scPM and scAM) concentrations. Scale PM and scAM concentrations were compared between sexes, while overall median values for scPM and scAM, as well as a ratio of scPM to scAM (P/A) were used as boundary values for sex identification. Neither scPM nor scAM concentrations were significantly different between the sexes and concentrations of a juvenile and sub-adult male overlapped with females, possibly indicating later sexual maturity in males. Boundary values for scAM concentrations and the P/A ratio predicted sex with 100% accuracy for females and 78% for males, while the accuracies for the scPM boundary value were lower. When only adult individuals are considered, scAM and P/A ratio boundaries are 100% accurate for both sexes. Therefore, scale hormone ratios show promise as a sex identification tool for Temminck's pangolin, particularly applicable in forensic investigations on the pangolin trade.

Massively parallel sequencing and capillary electrophoresis of a novel panel of falcon STRs: Concordance with minisatellite DNA profiles from historical wildlife crime

Birds of prey have suffered persecution for centuries through trapping, shooting, poisoning and theft from the wild to meet the demand from egg collectors and falconers; they were also amongst the earliest beneficiaries of DNA testing in wildlife forensics. Here we report the identification and characterisation of 14 novel tetramer, pentamer and hexamer short tandem repeat (STR) markers which can be typed either by capillary electrophoresis or massively parallel sequencing (MPS) and apply them to historical casework samples involving 49 peregrine falcons, 30 of which were claimed to be the captively bred offspring of nine pairs. The birds were initially tested in 1994 with a multilocus DNA fingerprinting probe, a sex test and eight single-locus minisatellite probes (SLPs) demonstrating that 23 birds were unrelated to the claimed parents. The multilocus and SLP approaches were highly discriminating but extremely time consuming and required microgram quantities of high molecular weight DNA and the use of radioisotopes. The STR markers displayed between 2 and 21 alleles per locus (mean = 7.6), lengths between 140 and 360 bp, and heterozygosities from 0.4 to 0.93. They produced wholly concordant conclusions with similar discrimination power but in a fraction of the time using a hundred-fold less DNA and with standard forensic equipment. Furthermore, eleven of these STRs were amplified in a single reaction and typed using MPS on the Illumina MiSeq platform revealing eight additional alleles (three with variant repeat structures and five solely due to flanking SNPs) across four loci. This approach gave a random match probability of < 1E-9, and a parental pair false inclusion probability of < 1E-5, with a further ten-fold reduction in the amount of DNA required (~3 ng) and the potential to analyse mixed samples. These STRs will be of value in monitoring wild populations of these key indicator species as well as for testing captive breeding claims and establishing a database of captive raptors. They have the potential to resolve complex cases involving trace, mixed and degraded samples from raptor persecution casework representing a significant advance over the previously applied methods.

International Wildlife Trafficking: A perspective on the challenges and potential forensic genetics solutions

International wildlife trafficking (IWT) is a thriving and pervasive illegal enterprise that adversely affects modern societies. Yet, despite being globally recognized as a threat to biodiversity, national security, economy, and biosecurity, IWT remains largely unabated and is proliferating at an alarming rate. The increase in IWT is generally attributed to a lack of prioritization to curb wildlife crime through legal and scientific infrastructure. This review: (1) lays out the damaging scope and influence of IWT; (2) discusses the potential of DNA marker systems, barcodes, and emerging molecular technologies, such as long-read portable sequencing, to facilitate rapid, in situ identification of species and individuals; and (3) encourages initiatives that promote quality and innovation. Interdisciplinary collaboration promises to be one of the most effective ways forward to surmounting the complex scientific and legal challenges posed by IWT.

Animal Forensic Genetics

Animal forensic genetics, where the focus is on non-human species, is broadly divided in two: domestic species and wildlife. When traces of a domestic species are relevant to a forensic investigation the question of species identification is less important, as the material comes from either a dog or a cat for instance, but more relevant may be the identification of the actual pet. Identification of a specific animal draws on similar methods to those used in human identification by using microsatellite markers. The use of cat short tandem repeats to link a cat hair to a particular cat paved the way for similar identification of dogs. Wildlife forensic science is becoming accepted as a recognised discipline. There is growing acceptance that the illegal trade in wildlife is having devasting effects on the numbers of iconic species. Loci on the mitochondrial genome are used to identify the most likely species present. Sequencing the whole locus may not be needed if specific bases can be targeted. There can be benefits of increased sensitivity using mitochondrial loci for species testing, but occasionally there is an issue if hybrids are present. The use of massively parallel DNA sequencing has a role in the identification of the ingredients of traditional medicines where studies found protected species to be present, and a potential role in future species assignments. Non-human animal forensic testing can play a key role in investigations provided that it is performed to the same standards as all other DNA profiling processes.

Wildlife crime in Australia

Wildlife crime is on a massive scale by whatever metric is used. The illegal trade in wildlife and related products is leading to the decline and extinction of many iconic species from rhino to tigers. Almost all countries are signatures to CITES and therefore should enforce national legislation if alleged infringements of trade of wildlife occur. No country is immune from this illegal trade although countries like Australia have their own specific wildlife crimes. Australia is home to many reptilian, amphibian and avian species that are highly prized, predominantly as pets. Collection of protected species from the wild is illegal in all jurisdictions yet policing remote areas of the outback, where so much of the native endemic fauna and flora lives, is nearly impossible. The illegal international trade in these species is highlighted by two case studies provided in this review. A further case highlights the issues of each of the six states of Australia having separate legislation, which is compounded when wildlife crime can be inter-state crime. Australia is one of the few countries having an institute, based at the Australian Museum, with an accredited wildlife forensic science laboratory and therefore the capability to undertake forensic testing of seized samples. One way to reduce wildlife crime may be by educating those who buy illegally seized products that there is a direct connection between the dead animal from which it came and the devasting effect this purchase has on the environment.

Optimisation and application of a forensic microsatellite panel to combat Greater-one horned rhinoceros (Rhinoceros unicornis) poaching in India

The Greater one-horned (GoH) rhinoceros is one of the most charismatic endemic megaherbivores of the Indian subcontinent. Threatened by poaching, habitat loss and disease, the species is found only in small areas of its historical distribution. Increasing demands for rhino horns in chinese traditional medicine has put the existing population under continuing threat, and large profits and low conviction rates make poaching difficult to contain. DNA forensics such as the RhoDIS-Africa program has helped in combating illegal rhino horn trade, but the approach is yet to be optimised for Indian GoH rhinoceros. Here we followed the International Society for Forensic Genetics (ISFG) guidelines to establish a 14 dinucleotide microsatellite panel for Indian GoH rhinoceros DNA profiling. Selected from a large initial pool (n = 34), the microsatellite markers showed high polymorphism, stable peak characteristics, consistent allele calls and produced precise, reproducible genotypes from different types of rhino samples. The panel also showed low genotyping error and produced high statistical power during individual identification (P_IDsibs value of 1.2*10^-4). As part of the official RhoDIS-India program, we used this panel to match poached rhino carcass with seized contraband as scientific evidence in court procedure. This program now moves to generate detailed allele-frequency maps of all GoH rhinoceros populations in India and Nepal for development of a genetic database and identification of poaching hotspots and trade routes across the subcontinent and beyond.

Phylogeography of the iconic Australian pink cockatoo, Lophochroa leadbeateri

The pink cockatoo (Lophochroa leadbeateri; or Major Mitchell’s cockatoo) is one of Australia’s most iconic bird species. Two subspecies based on morphology are separated by a biogeographical divide, the Eyrean Barrier. Testing the genetic basis for this subspecies delineation, clarifying barriers to gene flow and identifying any cryptic genetic diversity will likely have important implications for conservation and management. Here, we used genome-wide single nucleotide polymorphisms (SNPs) and mitochondrial DNA data to conduct the first range-wide genetic assessment of the species. The aims were to investigate the phylogeography of the pink cockatoo, to characterize conservation units and to reassess subspecies boundaries. We found consistent but weak genetic structure between the two subspecies based on nuclear SNPs. However, phylogenetic analysis of nuclear SNPs and mitochondrial DNA sequence data did not recover reciprocally monophyletic groups, indicating incomplete evolutionary separation between the subspecies. Consequently, we have proposed that the two currently recognized subspecies be treated as separate management units rather than evolutionarily significant units. Given that poaching is suspected to be a threat to this species, we assessed the utility of our data for wildlife forensic applications. We demonstrated that a subspecies identification test could be designed using as few as 20 SNPs.

Wildlife forensics: A boon for species identification and conservation implications

Wildlife trade and fraudulence in food, artefacts and cosmetic industries had raised serious concern in protection of the wild faunal diversity. Lack of proper tools and molecular based techniques for identification of wild species are some of the major constrains faced by the judiciary and law enforcement agencies while framing charges against poachers and illicit agitator. The emergence of wildlife forensics serves as a boon in solving long pending cases of wildlife crimes. Wildlife forensics have proven to be fast, accurate and reliable criminal investigation processes with comprehensive coverage and easy accessibility. It has also helped resolving taxonomic disputes, determining spatiotemporal genetic divergence, evolutionary history, origins and even endemism. Collaboration among inter-disciplinary fields has even led to engineered signature markers and phylogenetics for several species. Development in fields of genetics, molecular and evolutionary biology and other omics techniques have further contributed in accurate identification of species. Wildlife forensics, with the support of proper international mega database units for population reference, will be fundamental in wildlife investigations through its unlimited information sharing ability. The efficient conservation of species will, however, require a collaborative approach consisting of national policy makers, local stakeholders and implementation agencies in addition to experts from the scientific communities.

Current issues for mammalian species identification in forensic science: a review

Mammalian species identification is one of the important issues in forensic science. Determining the origins of non-human biological material found at crime scenes can increase the possibility of identifying the true culprit by narrowing down the range of suspects. Although many techniques based on mitochondrial DNA (mtDNA) have been developed, challenges remain to cost-effectively identify species from degraded samples containing a mixture of DNA from multiple species and to standardize procedures for mammalian species identification. This review evaluates the reliability and versatility of mtDNA-based techniques to reveal obstacles to the establishment of standard analytical methods, with a particular focus on DNA mixtures. When samples contain a mixture of DNA from multiple species, the interpretation of sequencing analysis results is difficult. Although DNA metabarcoding using next-generation sequencing (NGS) technologies can overcome the DNA mixture problem, DNA metabarcoding is not suitable for the type of small-scale analysis routinely performed by local forensic laboratories, primarily because it is costly and time-consuming. By contrast, fluorescent multiplex PCR analysis enables cost-effective and simultaneous species identification from suboptimal samples, although the number of identifiable species is currently limited in comparison with sequencing techniques. The advantages and limitations of current techniques presented in this review indicate that multiplex PCR analysis will continue to be important for mammalian species identification in forensic casework analysis. Further developments in multiplex PCR analysis that enable the identification of an increased number of species will play a key step for standardization efforts among forensic laboratories.

The visualisation of fingermarks on Pangolin scales using gelatine lifters

Recent media reports document the plight of the Pangolin and its current position as "the most trafficked mammal in the world". They are described by some as scaly anteaters as all species are covered in hard keratinous tissue in the form of overlapping scales acting as a "flexible dermal armour". It is estimated that between 2011 and 2013, 117,000-234,000 pangolins were slaughtered, but the seizures may only represent as little as 10% of the true volume of pangolins being illegally traded. In this paper, methods to visualise fingermarks on Pangolin scales using gelatine lifters is presented. The gelatine lifters provide an easy to use, inexpensive but effective method to help wildlife crime rangers across Africa and Asia to disrupt the trafficking. The gelatine lifting process visualised marks producing clear ridge detail on 52% of the Pangolin scales examined, with a further 30% showing the impression of a finger with limited ridge detail. The paper builds on an initial sociotechnical approach to establishing requirement, then it focuses on the methods and outcomes relating to lifting fingermarks off Pangolin scales using gelatine lifters, providing an evaluation of its use in practice.

Diversity of trypanosomes in wildlife of the Kafue ecosystem, Zambia

The Kafue ecosystem is a vast conservation protected area comprising the Kafue National Park (KNP) and the Game Management Areas (GMA) that act as a buffer around the national park. The KNP has been neglected as a potential foci for rhodesiense sleeping sickness despite the widespread presence of the tsetse vector and abundant wildlife reservoirs. The aim of this study was to generate information on circulating trypanosomes and their eminent threat/risk to public health and livestock production of a steadily growing human and livestock population surrounding the park. We detected various trypanosomes circulating in different mammalian wildlife species in KNP in Zambia by applying a high throughput ITS1-polymerase chain reaction (PCR)/nanopore sequencing method in combination with serum resistant associated-PCR/Sanger sequencing method. The prevalence rates of trypanosomes in hartebeest, sable antelope, buffalo, warthog, impala and lechwe were 6.4%, 37.2%, 13.2%, 11.8%, 2.8% and 11.1%, respectively. A total of six trypanosomes species or subspecies were detected in the wildlife examined, including Trypanosoma brucei brucei, T. godfreyi, T. congolense, T. simiae and T. theileri. Importantly we detected human infective T. b. rhodesiense in buffalo and sable antelope with a prevalence of 9.4% and 12.5%, respectively. In addition, T. b. rhodesiense was found in the only vervet monkey analyzed. The study thus reaffirmed that the Kafue ecosystem is a genuine neglected and re-emerging foci for human African trypanosomiasis. This is the first assessment of the trypanosome diversity circulating in free-ranging wildlife of the KNP.

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Detected six African trypanosomes in wildlife species of Kafue National Park using ITS1-PCR and Nanopore sequencing method.

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Confirmed presence of Trypanosoma brucei rhodesiense using SRA PCR.

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Identified unique divergence of SRA sequence of Trypanosoma brucei rhodesiense from buffalo, sable and vervet monkey.

Use of complete mitochondrial genome sequences to identify barcoding markers for groups with low genetic distance

Complete mitochondrial sequences can be rapidly obtained and are widely available, providing a great source of species information and allowing for the discovery of new specific molecular markers. However, for some taxonomic groups, traditional approaches for species delimitation are impaired by the low genetic distance values. In these cases, other species-level markers are used. For Prochilodus, which includes important neotropical fish species, species-level delimitation usually results in poor phylogenetic resolution when using mitochondrial COI/cytB genes as barcoding markers because of low genetic variability and low species-level resolution. Thus, in this study, we developed an approach to design and validate new barcoding markers with high species-level resolution obtained from the D-loop region, using Prochilodus spp. as a model. For the new barcoding marker validation, the amplicon region was used to infer the phylogenetic relationships of Prochilodus spp. through three distinct methods: Bayesian inference (BI), Neighbor-Joining method (NJ), and Maximum Likelihood method (ML). The phylogenetic relationships of Prochilodus spp. revealed high resolution at species-level, nonoverlapping clades, and high branch support. The genetic distance results allied to two different clustering methods (Bayesian Poisson tree processes and automatic barcode gap discovery) revealed the existence of a barcoding gap, thus, validating the use of the barcoding markers designed in this study. The approach proposed here may, therefore, be expanded to other taxa to access and validate new barcoding markers with higher resolution at the species level.

A combined morphological and molecular approach for hair identification to comply with the European ban on dog and cat fur trade

Animal furs are encountering more and more the detriment of public opinion, that is increasingly sensitive to animals, their welfare and protection. The feeling of outrage against animal suffering is particularly intense when cats and dogs are involved, since these are the most popular pets in Western countries. However, in some Asian countries breeding of dogs and cats for the fur industry is a common practice. These furs and their finished garments are often mislabelled in order to be imported and sold to unaware consumers in Western countries. The European Union has issued the Regulation 1523/2007, which bans the use and trade of dog and cat furs. The main purposes of the Regulation were to normalise the internal market and to address the concerns of European consumers about the risk of inadvertently buying products containing these species. The Regulation states that several analytical methods (microscopy, DNA testing and mass spectrometry) can be used to exclude dogs and cats as source species, but an official analytical protocol was not provided. In this paper, we report on the development of a reliable and affordable method for species identification in furs, based on a combined morphological and molecular approach. Our protocol provides an initial morphological analysis as a time and cost effective screening test. Only samples that are morphologically not excluded as canid/felid furs, based on few selected microscopic features, are then submitted to DNA testing. The application of this protocol on seized furs reached 92% identification of species. Our approach assists in identifying frauds and reinforcing the ban on dog and cat fur trade, allowing (1) rapid inexpensive recognition of fake furs, (2) exclusion of non-canid/non-felid furs through fast microscopic morphological screening, (3) overall cost reduction with lower number of samples to be submitted to DNA analysis, (4) analytical protocol to stand in court in case criminal sanctions are to be applied.

Defining end user requirements for a field-based molecular detection system for wildlife forensic investigations

The increasing use of non-laboratory-based DNA and protein detection methods promise to provide rapid investigative intelligence and support sample prioritisation. Primarily developed for human forensic or medical applications, current systems may also show utility in the field of wildlife forensic science. However, it is currently unknown whether the requirements of the wildlife forensic community can be met by current non-laboratory based tools. Given the diverse array of stakeholders and sample types commonly encountered, it is necessary to first identify the needs of the community and then try and map their needs to current instrumentation. By using a market research style questionnaire, this study identified key requirements for a non-laboratory-based system following feedback from the wildlife forensic community. Data showed that there is strong support for field-based detection methods while highlighting concerns including contamination risks and reduced quality assurance associated with non-laboratory testing. Key species and applications were identified alongside hurdles to implementation and adoption. Broadly, the requirements align with many of the developmental drivers that have led to the rise of in-field portable detection instrumentation, specifically rapid detection within one hour, ease-of-use, and ≥95% accuracy. Several existing platforms exist that met some of the identified requirements but not all. With further collaboration between industry partners and the wildlife forensic community it is possible that new field-based systems can be developed and applied routinely.

DNA based method for determining source country of the short beaked echidna (Tachyglossus aculeatus) in the illegal wildlife trade

The illegal trade in wild animals being sold as 'captive bred' is an emerging issue in the pet and zoo industry and has both animal welfare and conservation implications. DNA based methods can be a quick, inexpensive, and definitive way to determine the source of these animals, thereby assisting efforts to combat this trade. The short beaked echidna (Tachyglossus aculeatus) is currently one of the species suspected to be targeted in this trade. As this species is distributed throughout Australia and in New Guinea (currently comprising of five recognised sub-species), this project aimed to develop a DNA based method to definitively determine the source country of an echidna and explore the use of non-invasive sampling techniques. Here we use non-invasively sampled echidna quills and demonstrate the extraction of mitochondrial DNA and amplification of a region of the mitochondrial genome. Phylogenetically informative markers for analysis of a 322bp segment of the D-loop region were developed, and subsequently validated, using animals with known source locations allowing us to reliably distinguish between echidnas from New Guinea, and Australia. This research presents the first validated forensic protocols for short beaked echidnas and will be an integral tool in understanding the movement of animals in this emerging trade.

A method for extracting DNA from hard tissues for use in forensic identification

With deceased and decayed bodies, personal identification is performed using hard tissue DNA, commonly extracted from bone. The quantity and quality of DNA used in the polymerase chain reaction (PCR) amplification step is critical for a successful outcome. Since enamel is the strongest tissue in the human body, it was hypothesized that teeth may preserve DNA better than bones. In the present study, porcine teeth and bone samples were exposed to a variety of environments that imitated personal identification conditions, and DNA extracted from the teeth and bone samples was compared, using a PCR amplification method. The porcine teeth and bones were exposed to 11 different conditions for 5 different time periods to imitate a series of common crime scenes. DNA was extracted by a standard phenol-chloroform method. To test DNA quality, PCR was performed with primers designed to amplify porcine β-actin (ACTB) and mitochondrial DNA (mtDNA) sequences. The results demonstrated that the quality of DNA extracted from teeth was greater than that extracted from bone in the following environments: Buried in sand, soaked in caustic soda and burnt with rubber. By contrast, the quality of DNA extracted from bone was greater than that extracted from teeth when samples were buried in soil or submerged in water. There was no discernable difference in the quality of DNA extracted from bones and teeth in several environments, including being submerged in seawater, soaked in sulfuric acid, left in open air, and stored at 4, -20 and -80°C. Additionally, the results suggested that PCR using mtDNA primers performed better than that using ACTB primers. Finally, it was indicated that components of seawater may inhibit PCR amplification. The preliminary data reported here may provide basic guidelines for selecting the optimum source of DNA in each case.

Hindering the illegal trade in dog and cat furs through a DNA-based protocol for species identification

In Western countries dogs and cats are the most popular pets, and people are increasingly opposed to their rearing for the fur industry. In 2007, a Regulation of the European Union (EU) banned the use and trade of dog and cat furs, but an official analytical protocol to identify them as source species was not provided, and violations of law are still frequent in all Member States. In this paper we report on the development and validation of a simple and affordable DNA method for species detection in furs to use as an effective tool to combat illegal trade in fur products. A set of mitochondrial primers was designed for amplification of partial cytochrome b, control region and ND1 gene in highly degraded samples, like furs and pelts. Our amplification workflow involved the use of a non-specific primer pair to perform a first test to identify the species through sequencing, then the application of species-specific primer pairs to use in singleplex end-point PCRs as confirmation tests. The advantage of this two-step procedure is twofold: on the one hand it minimises the possibility of negative test results from degraded samples, since failure of amplification with a first set of primers can be offset by successful amplification of the second, and on the other it adds confidence and reliability to final authentication of species. All designed primers were validated on a reference collection of tissue samples, obtaining solid results in terms of specificity, sensitivity, repeatability and reproducibility. Application of the protocol on real caseworks from seized furs yielded successful results also from old and dyed furs, suggesting that age and chemical staining do not necessarily affect positive amplifications. Major pros of this approach are: (1) sensitive and informative primer sets for detection of species; (2) short PCR amplicons for the analysis of poor quality DNA; (3) binding primers that avoid contamination from human DNA; (4) user-friendly protocol for any laboratory equipped for analysis of low-copy-number DNA. Our molecular procedure proved to be a good starting point for enforcing the EU Regulation against dog and cat fur trade in forensic contexts where source attribution is essential to the assignment of responsibilities.

OzPythonPlex: An optimised forensic STR multiplex assay set for the Australasian carpet python (Morelia spilota)

Reptile species, and in particular snakes, are protected by national and international agreements yet are commonly handled illegally. To aid in the enforcement of such legislation, we report on the development of three 11-plex assays from the genome of the carpet python to type 24 loci of tetra-nucleotide and penta-nucleotide repeat motifs (pure, compound and complex included). The loci range in size between 70 and 550 bp. Seventeen of the loci are newly characterised with the inclusion of seven previously developed loci to facilitate cross-comparison with previous carpet python genotyping studies. Assays were optimised in accordance with human forensic profiling kits using one nanogram template DNA. Three loci are included in all three of the multiplex reactions as quality assurance markers, to ensure sample identity and genotyping accuracy is maintained across the three profiling assays. Allelic ladders have been developed for the three assays to ensure consistent and precise allele designation. A DNA reference database of allele frequencies is presented based on 249 samples collected from throughout the species native range. A small number of validation tests are conducted to demonstrate the utility of these multiplex assays. We suggest further appropriate validation tests that should be conducted prior to the application of the multiplex assays in criminal investigations involving carpet pythons.

Improved DNA-Based Identification of Cervidae Species in Forensic Investigations

The main reasons for wildlife forensic research are animal poaching, illegal trade, and falsified game meat products. Small trace amounts, old and degraded materials present the most common samples in revealing criminal activities in this field. This is the reason why it is crucial to use adequate and reliable methods and samples to identify animal species killed outside the hunting season or species protected by law. In this study, different endpoint PCR and real-time PCR protocols were compared in the identification of three Cervidae species (Capreolus capreolus, Cervus elaphus, Dama dama) from old and damaged material found in an enclosed area where the animals were kept. From a total of 129 samples, end point PCR provided results for 119 samples, while real-time PCR was successful in all cases. Also, we created and tested a protocol for simultaneous analyses of different types of samples, which is of great importance as when the amplification is carried out simultaneously it is more cost efficient and speeds up the process.

Polymerase chain reaction with nearby primers

DNA analysis of biological specimens containing degraded nucleic acids such as mortal remains, archaeological artefacts, forensic samples etc. has gained more attention in recent years. DNA extracted from these samples is often inapplicable for conventional polymerase chain reaction (PCR), so for its amplification the nearby primers are commonly used. Here we report the data that clarify the features of PCR with nearby and abutting primers. We have shown that the proximity of primers leads to significant reduction of the reaction time and ensures the successful performance of DNA amplification even in the presence of PCR inhibitors. The PCR with abutting primers is usually characterized by the absence of nonspecific amplification products that causes extreme sensitivity with limit of detection on single copy level. The feasibility of PCR with abutting primers was demonstrated on species identification of 100 years old rotten wood.

Polymorphic DNA microsatellite markers for forensic individual identification and parentage analyses of seven threatened species of parrots (family Psittacidae)

The parrot family represents one of the bird group with the largest number of endangered species, as a result of habitat destruction and illegal trade. This illicit traffic involves the smuggling of eggs and animals, and the laundering through captive breeding facilities of wild-caught animals. Despite the huge potential of wildlife DNA forensics to determine with conclusive evidence illegal trade, current usage of DNA profiling approaches in parrots has been limited by the lack of suitable molecular markers specifically developed for the focal species and by low cross-species polymorphism. In this study, we isolated DNA microsatellite markers in seven parrot species threatened with extinction (Amazona brasiliensis, A. oratrix, A. pretrei, A. rhodocorytha, Anodorhynchus leari, Ara rubrogenys and Primolius couloni). From an enriched genomic library followed by 454 pyrosequencing, we characterized a total of 106 polymorphic microsatellite markers (mostly tetranucleotides) in the seven species and tested them across an average number of 19 individuals per species. The mean number of alleles per species and across loci varied from 6.4 to 8.3, with the mean observed heterozygosities ranging from 0.65 to 0.84. Identity and parentage exclusion probabilities were highly discriminatory. The high variability displayed by these microsatellite loci demonstrates their potential utility to perform individual genotyping and parentage analyses, in order to develop a DNA testing framework to determine illegal traffic in these threatened species.

Identifying a hunter responsible for killing a hunting dog by individual-specific genetic profiling of wild boar DNA transferred to the canine during the accidental shooting

While genetic profiling can be a powerful tool to solve wildlife crime, comparably few examples of individual identification in wildlife forensics are available in the literature. Here, we report a case of an accidental shooting of a hunting dog during a wild boar drive hunt. The market value of trained hunting dogs can reach several thousand euro. No one admitted to killing the dog. Wild boar hairs were found in the dog's wound, suggesting that the bullet first hit a wild boar and then the dog. Since it was known who harvested each boar, we aimed to use individual-specific genetic profiles to link these hairs to a bagged animal and to identify the culprit. We genotyped 19 harvested boar and the unknown hair sample using 13 STRs. In the case of the hair sample, we performed multiple genotyping to ensure the reliability of the genetic profile. We showed that we genotyped sufficient loci to distinguish between separate individuals with certainty. While the three most informative loci were enough to differentiate the 19 reference individuals, we did find a perfect match at all 13 STRs between the hair DNA and one tissue sample. Since our methods were reliable and reproducible, we passed the relevant information on to forestry officials who will use the information we have provided to attempt to find an amicable solution.

Species detection using HyBeacon(®) probe technology: Working towards rapid onsite testing in non-human forensic and food authentication applications

Identifying individual species or determining species' composition in an unknown sample is important for a variety of forensic applications. Food authentication, monitoring illegal trade in endangered species, forensic entomology, sexual assault case work and counter terrorism are just some of the fields that can require the detection of the biological species present. Traditional laboratory based approaches employ a wide variety of tools and technologies and exploit a number of different species specific traits including morphology, molecular differences and immuno-chemical analyses. A large number of these approaches require laboratory based apparatus and results can take a number of days to be returned to investigating authorities. Having a presumptive test for rapid identification could lead to savings in terms of cost and time and allow sample prioritisation if confirmatory testing in a laboratory is required later. This model study describes the development of an assay using a single HyBeacon(®) probe and melt curve analyses allowing rapid screening and authentication of food products labelled as Atlantic cod (Gadus morhua). Exploiting melt curve detection of species specific SNP sites on the COI gene the test allows detection of a target species (Atlantic cod) and closely related species which may be used as substitutes. The assay has been designed for use with the Field Portable ParaDNA system, a molecular detection platform for non-expert users. The entire process from sampling to result takes approximately 75min. Validation studies were performed on both single source genomic DNA, mixed genomic DNA and commercial samples. Data suggests the assay has a lower limit of detection of 31 pg DNA. The specificity of the assay to Atlantic cod was measured by testing highly processed food samples including frozen, defrosted and cooked fish fillets as well as fish fingers, battered fish fillet and fish pie. Ninety-six (92.7%) of all Atlantic cod food products, tested, provided a correct single species result with the remaining samples erroneously identified as containing non-target species. The data shows that the assay was quick to design and characterise and is also capable of yielding results that would be beneficial in a variety of fields, not least the authentication of food.

'Skullduggery': Lions Align and Their Mandibles Rock!

South Africa has legally exported substantial quantities of lion bones to Southeast Asia and China since 2008, apparently as part of the multinational trade substituting bones and body parts of other large cats for those of the tiger in wine and other health tonics. The legal sale of lion bones may mask an illegal trade, the size of which is only partially known. An observed component of the illegal trade is that quantities of skeletons are sometimes declared falsely/fraudulently on CITES export permits. Furthermore, there are emerging concerns that bones from tigers reared in captivity in South Africa and elsewhere are being laundered as lion bones using CITES Appendix II permits. There is therefore a need for tools to monitor the trade in lion body parts and to distinguish between lions and tigers. Our research indicates that it is possible to use skeletons, skulls and cranial sutures to detect misdeclarations in the lion bone trade. It is also possible to use the average mass of a lion skeleton to corroborate the numbers of skeletons declared on CITES permits, relative to the weight of the consolidated consignments stated on the air waybills. When the mass of consolidated consignments of skeletons destined for export was regressed against the number of skeletons in that consignment, there was a strong correlation between the variables (r² = 0.992) that can be used as a predictor of the accuracy of a declaration on a CITES permit. Additionally, the skulls of lions and tigers differ: two cranial sutures of lions align and their mandibles rock when placed on a flat surface, whereas the cranial sutures of tigers are not aligned and their mandibles rest naturally on two contact points. These two morphological differences between the skulls of tigers and lions are easy to observe at a glance and provide a method for distinguishing between the species if illegal trade in the bones is suspected and the skulls are present. These identifications should ideally be confirmed by a DNA test to provide rigorous evidence to prosecute offenders violating CITES regulations.