Handbook of Forensic Genetics

The following sections are included:

• Contents
• Foreword
• Guide to Readers
• List of Contributors

The development and application of molecular tools to characterize biological evidence ushered in the field of forensic genetics (FG). Its growth has been phenomenal and the success stories are many and continue to arise every day. Indeed, FG has become the gold standard for the forensic science disciplines (Lynch, 2003). However, such accolades can give us a false sense of security and sometimes make us complacent regarding our achievements and more so our limitations. Therefore, it is important at times to step back and reflect on the practices and issues that confront FG, or for that matter, any applied science…

Perhaps Charles Darwin was exaggerating poetically on the seemingly infinite forms of life but undoubtedly the current and past biodiversity — some, if not most of which was unknown to him and still unknown to us — is prodigious. At the same time, he was publishing his most famous work, another researcher outside the scientific arena, Gregor Mendel, was determining how the distinctive characteristics of living beings are transmitted from parents to offspring. In his words (Mendel, 1866) “[‥] so far, no generally applicable law governing the formation and development of hybrids has been successfully formulated”, since “among all the numerous experiments made, not one has been carried out to such an extent and in such a way as to make it possible to determine the number of different forms under which the offspring of the hybrids appear, or to arrange these forms with certainty according to their separate generations, or definitely to ascertain their statistical relations”. He concluded that “to undertake a labor of such far-reaching extent […] appears, however, to be the only right way by which we can finally reach the solution of a question the importance of which cannot be overestimated in connection with the history of the evolution of organic forms” (italics are ours)…

The following sections are included:

• Introduction
• Processes Shaping Genetic Diversity
• Measuring Genetic Diversity and Selection
• Genetic Diversity in Humans
• Conclusions
• References

The following sections are included:

• Probability as a Mathematical Concept
• Statistics: The Art of Building Models
• Likelihood Ratios in Forensics: The Match Probability
• Conclusions
• References

The following sections are included:

• Introduction
• Classical Methods
• Complicating Factors
• The Parametric Approach
• Discussion
• References

The following sections are included:

• Introduction
• Method
• Simulations
• Results
• Discussion
• Acknowledgments
• References

Use of genetic markers to determine population relationships has a long history extending back to the use of the ABO blood group system in the early 20th century. In the middle of the last century, the field of genetic anthropology got a great boost with the documentation by Harris (1969) of extensive protein polymorphism in humans. The blood group and protein polymorphism data accumulated globally were integrated and published in the book “The History and Geography of Human Genes” by Cavalli-Sforza et al. (1994). By then, the interest in “blood groups” for anthropology was already declining because of the demonstration of polymorphism directly in the autosomal DNA by Kan and Dozy (1978a, 1978b) and then in mitochondrial DNA (mtDNA) by Cann et al. (1987). The number of documented DNA polymorphisms in the nuclear DNA increased exponentially in the first decade after 1978 (Figure 1) and has now reached millions (Abecasis et al., 2010; Auton et al., 2015). The amount of anthropological population data for mtDNA variation also increased greatly during the 1990's and continues today. It already was abundantly clear by the late 1980's that the number of autosomal DNA polymorphisms (then known as restriction fragment length polymorphisms — RFLPs) exceeded all previous types of human genetic markers for anthropological research. In 1994, Cavalli-Sforza started organizing what would become the Human Genome Diversity Project…

When biological material is obtained from a scene of crime, it is often possible to produce a DNA profile from small amounts of DNA. If more than one individual has contributed DNA to the crime scene stain, the resulting DNA profile is called a DNA mixture. The anal ysis of DNA mixtures continues to be an area of research. In particular, the interpretation of DNA mixtures based on statistical models have received considerable attention since the first publication by Evett et al. (1991) on the topic more than 20 years ago. DNA mix tures is still an active research area: at the International Conference on Forensic Inference and Statistics (ICFIC) 2014 in Leiden, at least 14 presentations were devoted to the analysis of DNA mixtures…

Population genetics focuse on the allele/haplotype frequency variation in populations, and the processes responsible for modelling that variation, namely genetic drift, selection, migration and mutation…

Broadly speaking, forensic genetics are rooted on the estimation of kinship likelihoods and on the analyses of mixtures. Indeed, from identity to very complex pedigrees, what is at stake is generally the estimation of genetic proximity among individuals and/or samples. Interestingly, the theoretical study of X-chromosomal inheritance has been receiving greater attention from scientists focused on nonhuman populations, likely due to some animal species having few autosomal markers (such as Drosophila) or even none (such as honeybee, whose complete genome is haplo-diploid)(see for example Grossman and Eisen, 1989; Grossman and Fernando, 1989; Fernando and Grossman, 1990). The picture, however, has been changing and the use of X-chromosomal markers has been invoked as an added value, particularly in complex kinship cases at forensics. In this chapter, we will try to provide a global perspective on this topic…

The following sections are included:

• Twenty Years of Forensic DNA Databases
• Basic DNA Database Principles
• Measuring the Success of a DNA Database
• Preventing Errors
• Future Developments
• References

The following sections are included:

• Introduction
• Data Sources and Sampling Strategy
• Quality Assessment
• Database Search Functions and Frequency Estimation Process
• Ancestry Information
• Forensic Tools
• Further Resources
• Summary
• Acknowledgments
• References

The following sections are included:

• Introduction
• Gaps and Needs
• MPS
• Potential Applications
• Concluding Remark
• Acknowledgments
• References

The following sections are included:

• Introduction
• Massively Parallel Sequencing — The Next Generation
• Conclusions and Future Perspectives
• Acknowledgments
• References

The following sections are included:

• Introduction
• Historical Cases and Prominent Cases of Missing Persons
• mtDNA from Post-Conflict Skeletal Remains
• Large Scale Post-Conflict DNA Identifications in the Western Balkans
• DNA Matching in Large Scale Missing Persons Applications
• DNA in Disaster Victim Identification (DVI)
• “Routine” Missing Persons
• DNA and the Living Missing
• Future Perspectives
• References

The following sections are included:

• Introduction
• Molecular Autopsy
• Sudden Unexpected Death
• Pharmacogenomics and Molecular Autopsy
• Future Directions
• Conclusion
• References

The following sections are included:

• Forensic Motivations for DNA Prediction of Human Appearance Traits
• Current Standing of Forensic DNA Phenotyping
• DNA Prediction of Pigmentation Traits
• Appearance Traits that May be Predictable from DNA in the Near or Distant Future
• Issues with Future Directions of Forensic DNA Phenotyping
• Acknowledgments
• References

The following sections are included:

• Scope of Wildlife Crime
• Legislation and Enforcement
• Scope of Wildlife Forensic Science
• Conclusion
• References

Recognition of human DNA analysis as an indispensable tool in forensic investigation has opened new avenues for non-human genetic analyses. Of the forensic specialties, animal DNA analysis stands as a fairly recent but powerful field. Animal forensic genetics is defined as “the application of relevant genetic techniques and theory to legal matters, or enforcement issues, concerning animal biological material“ (International Society for Animal Genetics, 2008)…

The following sections are included:

• Introduction
• Olive Oil
• Wine and Grapevines
• Honey
• Mushrooms
• Dairy Products
• Food Microbiology and Health Safety
• Tracing Transmission, Identity and Authenticity
• Next Generation of Forensic Tools and its Role for Food Quality and Safety
• References

The following sections are included:

• Introduction
• Genetics
• Methods for Classification
• References

The following sections are included:

• Microbial Forensics
• Taxonomic Concepts
• Phenotypic Characterization of Unknowns Using Gene Presence
• GenomeTrakr Network and Database of Foodborne Pathogens
• Acknowledgments
• References

The following sections are included:

• Evolutionary Principles in Microbial Forensics
• A Real Case
• References

Forensic evidence plays a vital role in court or during the investigation of a crime regardless of the respective legal environment. Forensic scientists or practitioners are expected to examine and interpret evidence thoroughly, objectively, reliably and according to the state-of-the-art of their specific discipline. Although judges or juries make their final conclusions based on all the information and findings, a single forensic report might be the information that makes the difference between acquittal and conviction especially when the evidence — like in forensic genetics — directly links a person to a crime. As these forensic experts are the dedicated specialists in a certain area, it is very difficult for non-experts to evaluate, if the before mentioned characteristics apply to reported forensic findings…

The following sections is included:

• Index