Review: domestic animal forensic genetics – biological evidence, genetic markers, analytical approaches and challenges

Abstract

This review highlights the importance of domestic animal genetic evidence sources, genetic testing, markers and analytical approaches as well as the challenges this field is facing in view of the de facto 'gold standard' human DNA identification. Because of the genetic similarity between humans and domestic animals, genetic analysis of domestic animal hair, saliva, urine, blood and other biological material has generated vital investigative leads that have been admitted into a variety of court proceedings, including criminal and civil litigation. Information on validated short tandem repeat, single nucleotide polymorphism and mitochondrial DNA markers and public access to genetic databases for forensic DNA analysis is becoming readily available. Although the fundamental aspects of animal forensic genetic testing may be reliable and acceptable, animal forensic testing still lacks the standardized testing protocols that human genetic profiling requires, probably because of the absence of monetary support from government agencies and the difficulty in promoting cooperation among competing laboratories. Moreover, there is a lack in consensus about how to best present the results and expert opinion to comply with court standards and bear judicial scrutiny. This has been the single most persistent challenge ever since the earliest use of domestic animal forensic genetic testing in a criminal case in the mid-1990s. Crime laboratory accreditation ensures that genetic test results have the courts' confidence. Because accreditation requires significant commitments of effort, time and resources, the vast majority of animal forensic genetic laboratories are not accredited nor are their analysts certified forensic examiners. The relevance of domestic animal forensic genetics in the criminal justice system is undeniable. However, further improvements are needed in a wide range of supporting resources, including standardized quality assurance and control protocols for sample handling, evidence testing, statistical analysis and reporting that meet the rules of scientific acceptance, reliability and human forensic identification standards.

Humans Are Animals, Too: Critical Commonalities and Differences Between Human and Wildlife Forensic Genetics

“…An additional concern when constructing databases of wild taxa is that most nonhuman species are more restricted in their movement by natural features such as rivers, lakes, and mountains as well as human‐associated development, resulting in haplotype and genotype frequencies that can vary widely between populations of the same species in different geographic areas, demanding broad sampling of populations over a species’ range. We will explore the need for centralized, managed databases in more detail later, as it is one of the wildlife forensics’ biggest challenges .…”

Comparing two commercial domestic dog (Canis familiaris) STR genotyping kits for forensic identity calculations in a mixed‐breed dog population sample

“…The Canine Genotypes™ Panel 1.1 Kit (catalog number: F860S) and the Canine Genotypes™ Panel 2.1 Kit (catalog number: F864S), manufactured by Thermo Fisher Scientific, are two commercial STR amplification kits that are currently available for identity testing and parentage verification in domestic dogs (Kanthaswamy ). Panel 1.1 was developed for service laboratories that perform routine parentage and identity testing.…”

“…Most animal forensic laboratories do not have the resources to establish large‐scale population databases for forensic casework (Kanthaswamy ). Population sampling efforts for building dog STR databases tend to be restricted to opportunistic sampling from local sources such as veterinary clinics and dog owners (Verscheure et al .…”

Forensic DNA Technological Advancements as an Emerging Perspective on Medico-Legal Autopsy: A Mini Review

“…In other cases, animal hair from a victim's body helps to reveal the perpetrator [221], or so-called "silent witnesses" such as plant remains [222] on corpses, or even evidence of algae from postmortem tissues, aid in determination of the manner of death [223]. Due to the increasingly particular importance of genetic analysis of nonhuman substances in these types of cases, forensic genetics today is progressively incorporating the examination of nonhuman genetic material to an ever greater extent [224]. In essence, the similarities in analog and ortholog variable components of genomes provide forensic investigation of nonhuman biological substances in the same manner as for human forensics, but distinctions existing in different organisms and species, i.e., genomic architectures, reproductive strategies and genetic diversity, are continuously broadening the dependent scientific areas.…”

“…In recent years, genome-wide analyses and MPS technology have revolutionized this broad field in any case, so it would not be practical to introduce the enormous variety of nonhuman forensic DNA analysis here, within this section. Due to the common coexistence of humans and domestic animals, dog violence on humans leading to fatal consequences represents a frequent type of case [224,[239][240][241][242]. In these cases, DNA can be separated from saliva from within the biting area, from animal hairs and sometimes blood, or bitten material, including the victims' clothing [40,219].…”