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Gettings, Katherine Butler. "Forensic Ancestry and Phenotype SNP Analysis and Integration with Established Forensic Markers." Thesis, The George Washington University, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3590467.
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When an evidential DNA profile does not match identified suspects or profiles from available databases, further DNA analyses targeted at inferring the possible ancestral origin and phenotypic characteristics of the perpetrator could yield valuable information. Single Nucleotide Polymorphisms (SNPs), the most common form of genetic polymorphisms, have alleles associated with specific populations and/or correlated to physical characteristics. With this research, single base primer extension (SBE) technology was used to develop a 50 SNP assay designed to predict ancestry among the primary U.S. populations (African American, East Asian, European, and Hispanic/Native American), as well as pigmentation phenotype. The assay has been optimized to a sensitivity level comparable to current forensic DNA analyses, and has shown robust performance on forensic-type samples. In addition, three prediction models were developed and evaluated for ancestry in the U.S. population, and two models were compared for eye color prediction, with the best models and interpretation guidelines yielding correct information for 98% and 100% of samples, respectively. Also, because data from additional DNA markers (STR, mitochondrial and/or Y chromosome DNA) may be available for a forensic evidence sample, the possibility of including this data in the ancestry prediction was evaluated, resulting in an improved prediction with the inclusion of STR data and decreased performance when including mitochondrial or Y chromosome data. Lastly, the possibility of using next-generation sequencing (NGS) to genotype forensic STRs (and thus, the possibility of a multimarker multiplex incorporating all forensic markers) was evaluated on a new platform, with results showing the technology incapable of meeting the needs of the forensic community at this time.
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Parrott, Jonathan James. "A molecular study of contemporary and museum Calliphoridae of forensic importance." Thesis, University of Portsmouth, 2013. https://researchportal.port.ac.uk/portal/en/theses/a-molecular-study-of-contemporary-and-museum-calliphoridae-of-forensic-importance(ab189b61-53a7-441e-b847-1b8d761288ca).html.
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Blowflies (Diptera: Calliphoridae) are commonly the first colonisers of carrion. Forensic entomologists are able to estimate a minimum post-mortem interval by examining the eldest immature stage collected from the scene. For a minimum post-mortem interval estimation to be calculated, developmental data of the species is commonly subtracted from total developmental time. Information regarding events prior to death such as post-mortem relocation, mortuary behaviour and origin can also be determined from collected samples, in particular those from archaeological sites. The information, however, relies on accurate species identification. Currently, several methods are employed on insect samples. These involve both morphological and molecular techniques. With the constant development of molecular genetics, new methods are being developed which show potential for species identification. This thesis examines the use of such techniques on both contemporary and museum-stored insect samples. Deep sequencing technology, nested-PCR and light microscopy were used to examine the utility of a combined approach for the identification of insect samples collected from two sets of mummified remains. In both cases, species identification was successful, and origin was determined in one case. Results showed the importance of a multi-technique approach, with emphasis on utilising both morphological and molecular techniques to assign identity. Multi-gene analysis was used to examine the utility of several genes from both mitochondrial and nuclear DNA to assign species status of the South African blowfly Calliphora croceipalpis (Diptera: Calliphroidae). Using the Cytochrome Oxidase I gene, Internal Transcribed Spacer 2 and the Carbamoylphosphate Synthetase gene, species identity was determined. It was found that identification of C. croceipalpis must be under taken with care due to possible morphological similarities due to founder effects with Calliphora vicina and it is recommended to use a multi-gene approach for identification of calliphorids. Inter-simple sequence repeat-polymerase chain reaction was investigated for its applicability as a rapid identification tool for forensically important calliphorids. Examining 26 calliphorid species and several populations within many of the species collected globally, the existence of species-specific bands was examined. Results showed that large amounts of interspecific and intraspecific variation were seen, with no species-specific bands detected. It is recommended that inter-simple sequence repeat not to be used as a rapid tool for calliphorid identification, but it may have a use as a population-based tool. The analysis of molecular techniques showed that with new recent techniques, such as next generation sequencing, the information that is gained from museum-stored samples, could aid in historical findings. Significant information such as geographic origin and historical events has been determined from molecular work. The use of a multi-gene approach is recommended when analysing closely related species, due to recent divergence. Analysing both nuclear and mitochondrial genes increase the accuracy of species identification. The use of a rapid molecular technique for identifying entomological samples would be a fundamental and valuable tool. Although cytochrome oxidase I amplification and sequencing are relatively time-consuming, they are more reliable indicator of species than inter simple sequence repeat analysis. It can therefore be concluded from this study that the application of molecular techniques for the identification of both contemporary and museum samples can provide a wealth of information to help both forensic and archaeological case studies.
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Palmour, Nicole. "Forensic applications of molecular genetics: ethics and law to inform policy issues." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66662.
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Molecular analysis of DNA variation has usurped the place of all earlier technologies in forensic identification of victims and suspects alike. Although the field of ethics has made attempts to cope with the plethora of available genetic information, especially in clinical application, there has been little scrutiny of emerging ethical issues in the forensic domain. Legal scholarship highlights some aspects of the emerging issues, with particular relevance to the challenges faced in court and those regarding individual liberties. The overall objective of this thesis was to evaluate the scientific validity, ethical acceptability and legal accountability of the forensic applications of molecular genetics. In particular, contemporary science has allowed us to access information far beyond what was originally anticipated, such that trace DNA can be obtained trivially from any individual. As a consequence, the scope and composition of existing DNA banks far exceeds the legislative mandate. Chapter 1 reviews the current legal standards for evidence and assesses the level of exactitude necessary for forensic DNA testing to meet evidentiary standards. An evaluation of current practices in DNA banking revealed adequate informed consent practices; the need for a re-examination of access to public health samples with attention to local population interests and the necessity for developing standardized guidelines for banking practices and uniform quality assessment measures (Chapter 2). Comparing current forensic and genomic markers revealed similar concordance and discordance rates with a slight performance advantage towards the forensic markers. The results indicate that multiple runs are necessary to ensure reliability (Chapter 3). A significant ethical issue arises from the forensic practice of surreptitious DNA sampling. This lack of transparency violates autonomy, threatens the legitimacy of the State's intL'analyse moléculaire des variations de l'ADN a supplanté toutes les technologies médicolégales antérieures d'identification des victimes et des suspects. Bien que le champ de l'éthique ait tenté de gérer la pléthore d'information génétique disponible, particulièrement dans les applications cliniques, il y a eu peu d'examen des enjeux éthiques émergeants dans le domaine médicolégal. La recherche juridique met en évidence certains aspects des enjeux émergeant avec une pertinence particulière pour les défis auxquels les tribunaux sont confrontés ainsi que les défis à l'égard des libertés individuelles.L'objectif général de cette thèse était d'évaluer la validité scientifique, l'acceptabilité éthique et la responsabilité légale dans les applications médicolégales de la génétique moléculaire. En particulier, la science contemporaine nous a permis d'accéder à des informations qui vont au-delà de ce qui était anticipé à l'origine si bien que des traces d'ADN peuvent être obtenues trivialement de tout individu. En conséquence, l'étendue et la composition des banques existantes d'ADN excèdent de loin le mandat législatif. Le premier chapitre revoit les standards légaux d'évidence et évalue le niveau d'exactitude nécessaire afin que les tests d'ADN médico-légaux rencontrent les standards d'évidence. Une évaluation des pratiques actuelles dans la mise en banque d'ADN a révélé des pratiques de consentement éclairé adéquate, le besoin de réexaminer l'accès aux échantillons de santé publique en portant l'attention aux intérêts des populations locales et la nécessité de développer des lignes directrices standardisées pour les pratiques de mise en banque et de mesures uniformes de l'évaluation de la qualité (chapitre 2). La comparaison des marqueurs médicolégaux actuels aux marqueurs génomiques a révélé des taux de concordance et de discord
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Bani, Rashaid Ayat H. "Clinical and Forensic Biomarkers in Human Hair." Ohio University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1407256298.
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Bostock, Esta. "Megaselia scalaris (Diptera: Phoridae), a fly of forensic interest : advances in chronobiology and biology." Thesis, University of Huddersfield, 2015. http://eprints.hud.ac.uk/id/eprint/26168/.
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Megaselia scalaris (Diptera, Phoridae) is a common species found amongst indoor and outdoor crime scenes and plays an important role in the decomposition of human remains and can be used following the forensic entomology approach for the estimation of the post mortem interval particularly in indoor cases. Several questions concerning the biology and the chronobiology of this species remain open. Circadian clocks have evolved to synchronize physiology, metabolism and behaviour to the 24-h geophysical cycles of the Earth. The understanding of the circadian clock mechanism is a crucial element of forensic entomology because it is able to control routines such as feeding, mating, ovipositing or emergence times. To describe the behaviour and the potential role that the circadian clock may have on both the locomotor activity and emergence times of the M.scalaris, using Trikinetics technology, used previously in Drosophilia studies allows for factual data rather than observational data seen in many journals. The activity rhythms of M.scalaris were monitored using light/dark photoperiods at 20 °C. Males and females both demonstrate that there are significant differences between dark and light conditions and further results establish that the flies are both diurnal and nocturnal in activity. The pupa emergence shows that there are different rhythms during full darkness conditions and light/dark conditions. In addition our experiments demonstrated that the activity of this species is clock regulated. Differences in locomotor activity between male and female flies were observed in the absence of food in continuous dark (DD), in contrast the activity of the two sexes don’t differ in continuous light (LL) or in presence of food both in DD and in LL conditions. Cold White, Blue, Green, Red and Yellow lights were used to test the light attractiveness. Males and females show different behaviour. In contrast females seem to be attracted to red light and they don’t present any directional behaviour under other light. Colonisation of carrion by insects allow for the post mortem interval (PMI) to be determined. However it is thought by some, that flies are not active during the night time period and therefore are not able to oviposit during this time. To put that into a forensic context, if eggs were located on a cadaver, the conclusion would be that death occurred during the previous day or before. Determining nocturnal oviposition in forensically important flies is of fundamental importance so that the PMI can be determined correctly by the forensic entomologist. Our experiments have demonstrated that M.scalaris were able to oviposit in dark conditions during the night. Insects colonise a cadaver in a predictable pattern otherwise known as the succession. Succession patterns may vary due to intrinsic and environmental factors, for example, has the cadaver been buried or is it located above ground. Colonisation in buried remains depend on the slower decomposition rate of buried bodies, reduced dispersion of the decomposition odours but as well the reduced accessibility to the body. Phoridae are commonly found amongst the entomofauna of exhumed bodies or coffins. The phorid M.scalaris has been reported as being able to dig up to 6 feet. Little information is available about the kind of soil this fly is able to dig through to reach a cadaver; two different kinds of soil were investigated: sand and sandy loam garden soil. The results showed that M.scalaris was able to excavate garden soil but not sand. Insect development rate is mainly temperature dependent, although other parameters like photoperiod, overcrowding and food availability can affect the developments. In addition several studies demonstrated that drugs and other chemicals can affect the growth of larvae, feeding on the dead body, leading to Inc.orrect mPMI estimations. Amitriptyline is a commonly used antidepressant in cases of major depressive disorder. It is a tricyclic molecule absorbed in the gastrointestinal tract and metabolized into the liver. This molecule shows a high toxicity results in cases of overdose. Studies on the effect of Amitriptyline on insect development and accumulation/excretion have been performed in the 1990’s on Parasarcophaga ruficornis (Diptera: Sarcophagidae) and on Calliphora vicina (Diptera: Calliphoridae) whereas no data are available for other taxa. The results of these studies demonstrated the non-effect of the molecule on the growth rate. In the same years Amitriptyline and derivates have been isolated from empty puparia of Megaselia scalaris and from skin and faecal material of Dermestes maculatus (Coleoptera: Dermestidae) collected from a mummified body in New England. The aim of our study was to investigate the effect that Amitriptyline, often found on cadavers, may have on the development of Megaselia scalaris. Our experiment showed that Amitriptyline had no effect on the size but saw a decrease in the developmental time of M.scalaris, so the mPMI estimation can be affected if based on the larval size and not on the complete development. The results reported and discussed in this thesis improve the knowledge about the biology of M.scalaris and its applicability in the forensic context.
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Jeffery, Kathryn. "Application to forensic genetics to the population biology of western lowland gorillas at LopeÌ, Gabon." Thesis, Cardiff University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.408771.
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Jacobsen, Karin Marie. "Investigating the Effects of Time and Temperature Degradation on Oral Bacteria Using qPCR for the Forensic Identification of Saliva." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1616585145662135.
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Apple, Kendra Kea. "Inquiry-based science for high school students: a forensic unit." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2585/.
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This project constitutes an instructional unit for honors biology that involves the use of science in the field of criminal investigation and forensics. Before beginning the unit, the learners should have mastered basic laboratory skills, including use of the microscope. They should also have an understanding of the basic structure and function of DNA and its role in heredity and protein synthesis. The standard time frame is 24 days with 70-minute periods, but can be easily adjusted to meet classroom needs. Several instructional strategies enhance student learning and make science fun. The unit is inquiry-driven and activity-based. Students are surprised by the crime, gather and analyze evidence, and work towards proposing an explanation. This real world problem involves the use of cooperative learning and a variety of assessment techniques.
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Wise, Natalie Marie. "Determining Ideal Swab Type For Collection Of The Microbiome For Forensic Identification Purposes." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1616345112960545.
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Day, Donnah Marie. "Development of immature blowflies and their application to forensic science." Access electronically, 2006. http://www.library.uow.edu.au/adt-NWU/public/adt-NWU20060731.111615/index.html.
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Schober, Cassandra C. (Cassandra Carolyn). "The Evolution, Applications, and Statistical Interpretations of DNA Typing in Forensic Science." Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc332776/.
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This thesis examines the evolution, applications, and statistical interpretations of DNA typing as a tool in the field of forensic science as well as in our criminal justice system. The most controversial aspect of DNA typing involves the determination of how likely it is that two people share the same DNA profile. This involves the use of population genetics and databases of allelic frequencies as well as some assumptions about population structuring.
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Thyssen, Patricia Jacqueline 1973. "Caracterização das formas imaturas e determinação das exigencias termicas de duas especies de califorideos (Diptera) de importancia forense." [s.n.], 2005. http://repositorio.unicamp.br/jspui/handle/REPOSIP/314337.
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Orientador: Aricio Xavier LinharesTese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-04T02:54:55Z (GMT). No. of bitstreams: 1 Thyssen_PatriciaJacqueline_D.pdf: 2658711 bytes, checksum: 6ae5d4aeb98843b0a14d74606d3f57c1 (MD5) Previous issue date: 2005
Resumo: A correta identificação e avaliação da idade de insetos envolvidos com a decomposição de cadáveres é de suma importância para a estimativa do intervalo pós-morte (IPM) na área das ciências forenses, particularmente quando o IPM é baseado em informações sobre o ciclo de vida de insetos necrófagos. Entretanto, a análise destes parâmetros em insetos, especialmente quando se encontram em seus estágios imaturos, é difícil mesmo para taxonomistas bem treinados. Além das minúsculas diferenças morfológicas que há entre várias espécies, algumas variáveis tais como temperatura e substâncias tóxicas podem afetar o seu tempo de desenvolvimento gerando um erro no cálculo do IPM. Entre os insetos envolvidos neste processo, as larvas de dípteros da família Calliphoridae são freqüentemente as mais predominantes consumidoras de carcaça e estão presentes em todos os estágios de decomposição. Assim, este estudo teve como objetivo caracterizar morfologicamente e avaliar o tempo de desenvolvimento e as exigências térmicas das formas imaturas de duas espécies de dípteros em diferentes temperaturas: Hemilucilia segmentaria (Fabricius) e Hemilucilia semidiaphana (Rondani) (Calliphoridae). Todos os experimentos foram realizados em câmaras climáticas com temperaturas controladas em 10, 15, 20, 25, 30 e 35ºC, com fotoperíodo de 12 horas e umidade relativa de 70%. Dieta artificial própria para larvas foi oferecida para que estas completassem seu desenvolvimento. Neste estudo, além da descrição e caracterização morfológica tradicional, também foram utilizadas as técnicas da reação em cadeia da polimerase, associada ao polimorfismo baseado no comprimento do fragmento de restrição (PCR-RFLP), para a identificação das duas espécies
Abstract: The correct identification and age determination of insect species involved in cadaver decomposition is of particular importance in estimating the post-mortem interval (PMI) in forensic sciences, particularly since the PMI is based on information on the life cycle of necrophagous insects. However, the correct identification of several insects species, especially in their immature stages, is difficult even for experienced taxonomists. In addition to the minuscule morphological differences between several species, there are some variables such as temperature and toxic substances that may affect the developmental time of insects, generating errors in the estimate of the PMI. Among the insects that are involved in cadaver decomposition, maggots of blowflies (Calliphoridae) are often the most important consumers of carrion and are present in all stages of decomposition. Thus, this study aimed to characterize morphologically and to evaluate the developmental time and the thermal requirements of the immature stages of two species of blowflies reared in different temperatures: Hemilucilia segmentaria (Fabricius) e Hemilucilia semidiaphana (Rondani) (Calliphoridae). All experiments were done in growth chambers with temperatures set at 10, 15, 20, 25, 30 and 35ºC, photophase of 12 hours and relative humidity at 70%. The maggots were reared using an artificial diet for their complete development. In addition to traditional morphological description and characterization of the immatures, the usefulness of the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to identify the two species mentioned above was also assessed in this study
Doutorado
Parasitologia
Doutor em Parasitologia
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Stamper, Trevor I. "Improving the Accuracy of Postmortem Interval Estimations Using Carrion Flies (Diptera: Sarcophagidae, Calliphoridae and Muscidae)." Cincinnati, Ohio : University of Cincinnati, 2008. http://rave.ohiolink.edu/etdc//view?acc_num=ucin1227108162.
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Thesis (Ph.D.)--University of Cincinnati, 2008.Advisor: Ronald DeBry (Committee Chair); Theresa Culley (Committee Member); Gregory Dahlem (Committee Member); George Uetz (Committee Member); Anthony Perzigian (Committee Member). Title from electronic thesis title page (viewed Dec. 27, 2009). Keywords: Forensic entomology; sarcophagidae; calliphoridae; nocturnal oviposition. Includes abstract. Includes bibliographical references.
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Lang, Jennifer M. "The micro-ecology of stream biofilm dynamics: environmental drivers, successional processes, and forensic applications." University of Dayton / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1438084044.
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Hans, Krystal R. "Insect Signature Indicating Corpse Movement From Urban to Rural Areas of Northeast Ohio." Cleveland State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=csu1295366688.
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Young, Alexandria. "An investigation of patterns of mammalian scavenging in relation to vertebrate skeletal remains in a Northwestern European context : forensic applications." Thesis, Bournemouth University, 2013. http://eprints.bournemouth.ac.uk/21203/.
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Mammalian scavenging, disarticulating, scattering and removal of human remains can alter and obscure both soft tissue and skeletal remains which are essential to making interpretations and identifications during forensic investigations. The effects of scavenging vary between regions, environments, scavenger species, and crime scene scenarios due to a variety of factors. Nonetheless, there is a gap in the knowledge of scavenger species found within Northwestern Europe. The red fox (Vulpes vulpes) and Eurasian badger (Meles meles) are the largest wild mammalian scavenger species inhabiting peri-urban and rural environments within Northwestern Europe. These mammalian scavengers have dentitions and bite forces capable of heavily modifying and widely transporting human remains yet there are currently no species-typical and region-specific studies of these scavengers and their impacts on forensic investigations and physical searches for human remains. Forensic scientists, investigators and police search officers have been forced to rely on anecdotal evidence and scavenging studies focused on scavengers not found in this region. Scavenging studies have previously concentrated on scavenger species found in North America and Africa, such as coyote (Canis latrans), wolf (Canis lupus), hyena (Crocuta crocuta), lion (Panthera leo) and leopard (Panthera pardus), which have differing species-typical scavenging behaviour and patterns in comparison to foxes and badgers. Likewise, knowledge of the characteristics of the effects on bone surfaces of fox and badger scavenging is lacking, more so for the latter scavenger. The overall aim of this thesis is to aid forensic investigations by filling the gaps in the knowledge and identification of red fox and Eurasian badger species-typical scavenging behaviour and patterns. Avian scavenging can also modify soft tissue and skeletal remains. The buzzard (Buteo buteo) and carrion crow (Corvus corone) are the most common avian scavengers within this region. The scavenging behaviours of these avians modified soft tissue and affected mammalian scavengers’ scavenging behavours. A survey of police search officers within the U. K. indicated that the scavenging of surface deposited human remains within this region is common and that scavenging affects the recovery rates of remains. Despite the impact of scavenging on the recovery of scavenged remains, there is a lack of knowledge and literature available to forensic scientists, investigators, and police search officers to aid in the identification of scavenger species and scavenger species-typical scavenging behaviour and patterns. Thus these forensic professionals have been relying primarily on anecdotal evidence to identify scavengers or have not made efforts to identify scavengers. Experiments, conducted in southern England, using deposited deer (Cervus nippon; Capreolus capreolus) and the observation of captive scavengers found that within a woodland environment common scavengers include wood mouse (Apodemus sylvaticus), grey squirrel (Sciurus carolinensis), carrion crow, buzzard, Eurasian badger, and red fox. Scavenging activities by all scavenger species observed at remains were affected in various ways by seasonality, trophic resources, territoriality, insect activity, carcass size and condition, and decomposition. Of those scavengers, the red fox was the most frequent scavenger of surface deposited remains. The species-typical scavenging behaviour and pattern, as well as bite mark dimensions, of the red fox proved to differ to that of badgers and other canids, such as domestic dogs (Canis familiaris), coyotes and wolves. The benefits of the knowledge of scavenger species-typical scavenging behaviour and pattern to forensic investigations and physical searches were assessed by applying the results gained from the experiments within this research to current forensic investigations and search exercises performed with police search officers. The application of information on species-typical scavenging behaviour and patterns was found to improve police search officers’ search and recovery efforts of scavenged remains.
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Paul, Justin. "Categorization of shedding status: Proposing a standard grouping method for DNA shedding." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1555676870671746.
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Jollie, Melissa Lynn. "Determining Optimal Swab Type and Elution Buffer to Obtain WholeCells for Future Deconvolution of Complex Cell Mixtures." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu161667366449865.
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Warren, Joseph E. "Mutation Rate Analysis of the Human Mitochondrial D-loop and its Implications for Forensic Identity Testing." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2492/.
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To further facilitate mitochondrial DNA (mtDNA) sequence analysis for human identity testing, a better understanding of its mutation rate is needed. Prior to the middle 1990's the mutation rate applied to a forensic or evolutionary analysis was determined by phylogenetic means, This method involved calculating genetic distances as determined by amino acid or DNA sequence variability within or between species. The mutation rate as determined by this method ranged from 0.025-0.26 nucleotide substitutions/ site/ myr (million years). With the recent advent of mtDNA analysis as a tool in human identity testing an increased number of observations have recently come to light calling into question the mutation rate derived from the phylogenetic method. The mutation rate as observed from forensic analysis appears to be much higher than that calculated phylogenetically. This is an area that needs to be resolved in human identity testing. Mutations that occur within a maternal lineage can lead to a possible false exclusion of an individual as belonging to that lineage. A greater understanding of the actual rate of mutation within a given maternal lineage can assist in determining criteria for including or excluding individuals as belonging to that lineage. The method used to assess the mutation rate in this study was to compare mtDNA sequences derived from the HVI and HVII regions of the D-loop from several different maternal lineages. The sequence information was derived from five unrelated families consisting of thirty-five individuals. One intergenerational mutational event was found. This derives to approximately 1.9 nucleotide substitutions/ site/ myr. This mutation rate was very consistent with several other similar studies. This increased mutation rate needs to be considered by forensic testing laboratories performing mtDNA sequence analysis prior to formulating any conclusive results.
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Osborne, Daniel L. "An analysis of developmental plasticity in structural geometry at the proximal femur in adolescent females living in the United States." [Bloomington] : Indiana University, 2007. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3264308.
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Thesis (Ph.D.)--Indiana University, Dept. of Anthropology, 2007.Source: Dissertation Abstracts International, Volume: 68-05, Section: A, page: 2031. Advisers: Della Collins Cook; David Burr. Title from dissertation home page (viewed Jan. 9, 2008).
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Wagner, Sarah Jean. "Efficiency of DNA Recovery from Different Swab Types by qPCR." Bowling Green State University / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1616962034143618.
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Tise, Meredith L. "Craniometric Ancestry Proportions among Groups Considered Hispanic: Genetic Biological Variation, Sex-Biased Asymmetry, and Forensic Applications." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5141.
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Today, groups considered Hispanic in the United States consist of populations whose complex genetic structures reflect intermixed diverse groups of people who came in contact during Spanish colonization in Latin America. After coming in contact and wiping out most of the Native Americans who occupied North and Latin America, the Spanish also introduced West African individuals for labor to begin developing crops to be shipped back to Europe, resulting in the Trans-Atlantic African slave trade. These migration events and differential gene flow among males and females that occurred throughout Latin America have led to populations that have been genetically transformed from what they were prior to Spanish arrival (Madrigal, 2006).
Genetic research commonly refers to individuals considered Hispanic as "tri-hybrids" of Native American, European, and African ancestry (Bertoni et al., 2003; Gonz[aacute]lez-Andrade et al., 2007). This research focuses on populations from present-day Mexico, Puerto Rico, and Cuba, all of whom experienced various population histories as these three ancestral groups came in contact. Published genetic research demonstrates that individuals from Mexico tend to have the highest mean proportion of Native American ancestry, while Puerto Rican individuals have the highest mean proportion of European ancestry, and Cuban individuals have the highest mean proportion of African ancestry (Bonilla et al., 2005; Lisker et al., 1990; Mendizabal et al., 2008; Tang et al., 2007; Via et al., 2011). The present research utilizes craniometric data from these three groups to determine whether the cranial morphology reflects similar population relationships and mean ancestry proportions as found in genetic research through Mahalanobis distance (D2), canonical discriminant function, and normal mixture cluster analyses. Sex-biased ancestry asymmetry was also tested by separating each group by sex and running the same analyses.
The results show that all three groups considered Hispanic (Mexico, Puerto Rico, and Cuba) are significantly different from each other; however, when proxy ancestral groups are included (Guatemalan Mayan, Indigenous Caribbean, Spanish, and West African), the Mexican and Guatemalan Mayan samples are the most similar, followed by the Mexican and Indigenous Caribbean samples and the Puerto Rican and Cuban samples. The results of the normal mixture analyses indicate that Mexico has the highest mean ancestry proportion of Native American (Guatemalan Mayan) (72.9%), while the Puerto Rican and Cuban samples both have a higher mean European ancestry proportion, with 81.34% and 73.6% respectively. While the Cuban sample is not reflective of the genetic research in regards to ancestry proportion results, with the highest proportion of African ancestry over European and Native American ancestry, it does have the highest proportion of African ancestry among the three groups (18.4%). When separated by sex, the results indicate that the Mexican and Puerto Rican samples may show some evidence in sex-biased ancestry proportions, with the male individuals having a larger proportion of European ancestry and the female individuals having a larger proportion of Native American or African ancestry. Cuba, on the other hand, does not follow this trend and instead displays a higher proportion of European ancestry in females and a higher proportion of Native American and African ancestry in the males.
Techniques in the field of forensic anthropology in the United States are constantly being reanalyzed and restructured based on the changing demographics of the population, especially with the arrival of individuals from Latin America (Ennis et al., 2011). Recent samples of American Black and White individuals were included in the Mahalanobis distance (D2) and canonical discriminant function analyses in place of the ancestral proxy groups to determine the craniometric relationship of the groups within the United States. The results show that the Mexico and Guatemala samples are the most similar (D2=2.624), followed by the Cuba and American Black samples (D2=3.296) and the Puerto Rico and American White samples (D2=4.317), which each cluster together in pairs. These results reflect the population histories that took place during colonialism, with the largest amount of slave trade occurring in Cuba over the other two countries. From an applied perspective, clarification is needed in the biological definition of Hispanic and the degree of heterogeneity in each social group, as well as the relationship among groups, in order to accurately develop techniques in forensic anthropology for human identification.
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Carvalho, Suzana Papile Maciel. "Estudo estimativo do sexo em crânios da região de Guarulhos-SP utilizando antropologia física e DNA." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/23/23153/tde-13042013-124410/.
Full textAbstract:
A investigação do sexo é uma das análises mais importantes na identificação humana. Este trabalho teve como objetivo a determinação do sexo em crânios humanos utilizando três métodos de Antropologica Física, duas quantitativas (Forensic Data Anthropolgy Bank, FDB, 1986 e Oliveira, 1995) e uma qualitativa, (Walker, 2008), e a análise genética pela amelogenina. A amostra foi composta de 66 crânios (34 homens e 32 mulheres) do Centro de Estudo e Pesquisa em Ciências Forenses, Guarulhos, SP. As metodologias foram aplicadas por duas pesquisadoras, que desconheciam o sexo dos crânios. Para o estudo estatístico realizaram-se análise descritiva, média, desvio padrão, análise discriminante linear e logística e regressão logística. A metodologia quantivativa apresentou um acerto de 89,52%. O Método FBD teve uma acurácia de 92,31%, com a elaboração de uma fórmula utilizando as medidas Largura Bizigomática, Altura Nasal, as quais apresentaram o maior dimorfismo entre os sexos, e Altura Básio-bregma e Máximo Comprimento do Crânio. A metodologia de Oliveira et al. (1995) necessitou de ajuste para a população estudada (nova fórmula com acurácia de 76,47% em homens e 78,13% em mulheres). Para o DNA, foi possível determinar o sexo em 86,15% da amostra. Pode-se afirmar que as diferentes metodologias comportaram-se de modo semelhante e com alta acurácia para determinação do sexo. A antropologia física apresenta as vantagens de facilidade de aplicação, reprodutibilidade e baixo custo, porém, necessita de ajustes populacionais. O DNA é mais complexo, necessita de infraestrutura e insumos específicos e pode ter interferência da condição ambiental, fatores que dificultam as análises, entretanto, não precisa ser ajustado á população.The investigation of the sex is one of the most important analyzes in the human identification. This study aimed to determine the sex in human skulls using three methodologies of Physical Anthropology, two quantitative (Forensic Data Anthropology Bank, FDB, 1986 e Oliveira, 1995) and one qualitative (Walker, 2008) and genetic analysis by amelogenin. The sample was composed by 66 skulls (34 men and 32 women) from the Center for Study and Research in Forensic Science, Guarulhos, SP. The methodologies were applied by two researchers who were unaware of the craniums sexes. For the statistical analysis, there were performed descriptive analysis, average, standard deviation, linear discriminant analysis and logistic and logistic regression. The quantitative methodology presented an accuracy of 89.52%. The FBD method had an accuracy of 92.31%, with the development of a mathematical model using the measures Bizygomatic breadth, Nasal heigh, which showed the biggest dimorphism between the sexes, and Basion-bregma height and Maximum Cranial Length. The Oliveiras et al. (1995) methodology required adjustment for the studied population (new formula with an accuracy of 76.47% in men and 78.13% in women). For the DNA, it was possible to determine the sex in 86.15% of the sample. The different methodologies behaved similarly and with high accuracy in sex determination. Physical anthropology has the advantages of being easy to use, reliability and low cost, but needs population adjustments. The DNA is more complex, requires specific reagents and structure and may have interference from environmental condition, however, does not need to be adjusted to the population.
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Thompson, Lindsay Paige. "Degenerate Oligonucleotide Primed - Polymerase Chain Reaction Evaluation And Optimization To Improve Downstream Forensic STR Analysis Of Low Quality/Low Quantity DNA." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1299.
Full textAbstract:
When forensic biological samples yield low quality/low quantity DNA, thecurrent STR analysis methods do not generate acceptable profiles. Whole genomeamplification can be used to pre-amplify the entire genome for downstream analyses. A commercially available kit for DOP-PCR, a form of WGA, is currently being used in the clinical for downstream single locus targets. Forensic analyses utilize a multiplex amplification. This study determined that the "home brew" created by our lab performs the same as the commercially available kit. Future optimization studies of DOP-PCR can utilize this "home brew". Additionally, this research determined that a 10 second increase in electrokinetic injection time onto the Capillary Electrophoresis (CE) in combination with a post-STR amplification purification and elution into formamide produces a slightly higher percent STR allele success over the standard protocol. After future optimization studies, this may be a useful method to obtain more accurate and complete STR profiles from low quality/low quantity biological samples.
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Antunes, Joana AP. "The Study of Tissue-Specific DNA Methylation as a Method for the Epigenetic Discrimination of Forensic Samples." FIU Digital Commons, 2017. https://digitalcommons.fiu.edu/etd/3676.
Full textAbstract:
In forensic sciences, the serological methods used to determine which body fluid was collected from the crime scene are merely presumptive or labor intensive since they rely on protein detection or on microscopic identification of cells. Given that certain forensic cases may need the precise identification of a body fluid to determine criminal contact, such is the example of a suspected sexual assault of a minor; certainty in the body fluid of origin may depict a precise picture of the events. The identification of loci that show differences in methylation according to the tissue of origin can aid forensic analysts in determining the origin of a DNA sample. The process of DNA methylation occurs naturally in the genome of living organisms and consists in the presence of a methyl group on the carbon 5 of a cytosine, which is typically followed by a guanine (CpG). Analyzing patterns of DNA methylation in body fluids collected from a crime scene is preferential to the analysis of proteins or mRNA since the same extracted DNA used for STR typing can be used for DNA methylation analysis. We have validated and identified loci able to discriminate blood, saliva, semen and vaginal epithelia. In the current study, we have also established the minimum amount of DNA able to provide reliable results using methodologies such as pyrosequencing and high-resolution melt (HRM) analysis for the different markers identified. Lastly, we performed an alternative bioinformatic analysis of data collected using an array that studied methylation in over 450,000 individual cytosines on the human genome. We were able to sort the locations that showed potentially higher methylation differences between body fluids and investigated over 100 of them using HRM analysis. The results of that study, allowed the identification of three new loci able to distinguish blood and two new loci able to distinguish saliva and vaginal epithelia, respectively. The use of DNA methylation patterns to aid forensic investigations started with a publication in 2010, therefore each small contribution such as this work may, similarly to what occured in the biochemistry field, result in the discovery of a method able to put the technology in the hands of forensic analysts.
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Stobinski, Kristin. "Retrieving Low-Level DNA Samples from Clothing." Bowling Green State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1555677014819609.
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Carvalho, Suzana Papile Maciel. "Avaliação da qualidade do DNA obtido de saliva humana armazenada e sua aplicabilidade na identificação forense em odontologia legal." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/25/25141/tde-02062009-105931/.
Full textAbstract:
A saliva pode ser utilizada como fonte eficiente de DNA para tecnicas de identificacao humana, as quais sao aceitas como prova legal, sendo o parecer do profissional superlativo para a formulacao da sentenca. Esse material pode ser coletado de maneira indolor e nao-invasiva e utilizado mesmo quando armazenado em diferentes condicoes. Este trabalho objetiva avaliar a qualidade do DNA obtido de saliva humana armazenada e sua aplicabilidade da identificacao de pessoas. Foram analisadas amostras salivares de n=100 sujeitos da pesquisa, coletadas nas formas de saliva in natura e saliva coletada de swab. A saliva foi armazenada a -20ºC. Apos 7 dias, realizou-se a primeira etapa, quando o DNA foi extraido das 200 amostras de saliva utilizando-se a resina InstaGene (Bio-Rad Laboratories, Inc., Hercules, CA, USA) e, posteriormente, submetido a PCR e a eletroforese. Apos 180 dias de armazenamento da saliva, repetiu-se a mesma tecnica da primeira fase, porem em apenas 20 amostras, selecionadas aleatoriamente do total de 100 amostras de saliva coletadas por swab bucal. Os resultados da primeira etapa indicaram que o DNA foi extraido com sucesso em 96% das reacoes realizadas para as 200 amostras de saliva, fato observado tambem quando se analisou as amostras em separado, de saliva in natura (94%) e saliva advinda do swab (98%). Alem disso, nao houve diferencas estatisticamente significantes na extracao do DNA entre as duas formas de coleta de saliva utilizadas. Na segunda fase, foi possivel a deteccao do gene alvo nas 20 amostras analisadas (100%). Posteriormente, objetivando-se aprofundar a analise do DNA salivar de maneira mais proxima ao padrao exigido em um processo de identificacao, o gene SIX3-2 foi testado nas amostras e tambem foi feita a digestao do produto da PCR com a enzima de restricao MbO1 para avaliar polimorfismo do gene ADRA-2. Os resultados mostraram que a quantidade e a qualidade do DNA advindo de saliva do swab bucal, bem como as tecnicas empregadas estao adequadas a analise forense do DNA. Portanto, a saliva humana e bastante util como fonte de DNA e pode ser armazenada, em temperatura e condicoes ideais, para analise posterior.The saliva can be used as efficient DNA source for human identification techniques in which they are accepted as forensic proof, being the superlative professionals opinion for the sentence formulation. This material can be collected in a painless and noninvasive way and it is used even when stored in different conditions. This paper aims at evaluating DNA quality obtained from stored human saliva and its applicability in people identification. Saliva samples from n=100 research subjects were analyzed. They were collected in two ways: in natura and swab. The saliva was stored at the temperature of -20°C. After 7 days, the first phase was performed, when the DNA was extracted from the 200 saliva samples using the InstaGene resin (Bio-Rad Laboratories, Inc., Hercules, CA, USA) and, subsequently, submitted to PCR and electrophoresis. After 180 days of the saliva storage, the same technique used in the first phase was repeated; however, in only 20 samples, selected at random from the total of 100 ones collected from mouth swab. The results of the first phase indicated that the DNA was successfully extracted in 96% of the reactions performed for the 200 saliva samples. This fact was also observed when the separate saliva samples in natura (94%) and swab (98%) were analyzed. In addition, there were no statistically significant differences in the extraction of the DNA between the two ways used for collecting saliva. In the second phase, the target gene detection was possible in the 20 samples analyzed (100%). Subsequently, the SIX3-2 gene was tested in the samples with the objective of deepening the salivary DNA analysis as close as the standard required in an identification process. Also, the digestion of the PCR product with the enzyme of MbO1 restriction was performed to evaluate the polymorphism of the ADRA- 2 gene. The results showed that the DNA quantity and quality from the mouth swab saliva, as well as the techniques applied are suitable for the forensic analysis of DNA. Therefore, the human saliva is very useful as DNA source and can be stored in ideal temperature and conditions for further analysis.
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Nazir, Muhammad Shahid. "DNA persistence and preservation following environmental insult." Thesis, University of Central Lancashire, 2012. http://clok.uclan.ac.uk/6744/.
Full textAbstract:
This research was conducted to provide empirical evidence to supplement advice available to the forensic community for the collection of muscle tissue for forensic analysis. This type of collection is normally carried out to determine the identity of individuals following mass disasters, such as plane crashes or natural disasters. DNA degradation was assessed in two model organisms, pig and rabbit (with human DNA as a control), over various time points. Rabbit recombination activating gene (RAG 1) was aligned to identify conserved regions in pig, rabbit and human. Primers were designed and optimised to create a 4-plex PCR multiplex that can amplify 70 bp, 194 bp, 305 bp and 384 bp in three species. The 4-plex multiplex was found to work efficiently in all three species down to 0.3 ng of DNA template. The multiplex was used to assess whether DNA degradation can be predicted by accumulated degree-days (ADD), which provides a measure of both time and temperature. A series of field studies were performed to assess DNA persistence in pig and rabbit soft muscle tissues using a combination of whole animals, suspended muscle tissues (insect activity free) and muscle fragments. Field studies were carried out in: August-September 2009; February-May 2010; May-June 2010; June-July 2010 and September-November 2010. Soft muscle tissue samples were collected at different ADD. 4-plex multiplex results showed that DNA was more persistent in pig tissues compared to rabbit tissues. In the September 2010 experiments, full multiplex amplification was obtained from rabbit until 137 ADD (whole carcases) and 210 ADD (body fragments and suspended tissues), while in the August 2009 experiments, full multiplex amplification was obtained until 112 ADD (whole carcases and body fragments) and until 141 ADD (suspended tissues). In the June 2010 experiments, full multiplex amplification was possible until 64 ADD. Pig whole carcases which were placed in the field in February 2010, showed multiplex amplification until day 90 (603 ADD), followed by September 2010 (until day 44 (490 ADD)) and May 2010 (until day 27 (338 ADD)). During the September 2010 project, body fragments produced full amplification until muscles were collected (342 ADD), while in case of whole carcases and suspended tissues; the amplification was possible until 490 ADD. There was complete failure of amplification of 305 bp and 384 bp in pig whole carcases after 342 ADD, while in suspended tissues, the amplification of 305 bp and 384 bp was possible until 420 ADD. The statistical analysis showed that amplification success of larger amplicons (194 bp, 305 bp and 384 bp) reduces with increase in ADD in pig and rabbit whole carcases, body fragments and suspended tissues while 70 bp was more persistence. The results showed that there was no significant difference in DNA persistence between whole carcases verses suspended tissues (Z=0.57, p>0.05) and whole carcases verses body fragments (Z=1.71, p>0.05), There was however a significant difference (Z=2.31, p<0.05) in DNA persistence in suspended tissues and body fragments with increase in ADD. The results from field experiments suggested that muscle tissues, if available, should be collected for DNA profiling, since even if degraded, a profile can be obtained. The results also suggested that the isolation of tissues from insect activity as quickly as possible (even if immediate storage is not possible) may be beneficial for DNA persistence. Seasonal variation in DNA persistence was observed due to maggot mass growth which increases carcase decomposition and ultimately effect on DNA persistence. Controlled incubation experiments were also performed at 27 °C, 37 °C and 47 °C until 21 days to assess DNA persistence, as these temperatures were not available under field conditions. The results showed that the amplification of 70 bp was more persistent compared to larger amplicons (194 bp, 305 bp and 384 bp). The drop-out in amplification of larger amplicons occurred more rapidly in samples incubated under laboratory conditions compared to the field samples. The statistical analysis showed species, ADD and temperature have strong effect (p<0.05) on DNA persistence under controlled conditions. The appearance of 70 bp amplicons in all samples collected from field and in most samples from controlled incubation experiments suggested that soft muscle tissues exposed to different environments can be used to perform SNP analysis. The full 4-plex multiplex amplification obtained from rabbit and pig preserved and dehydrated samples suggested that 96% ethanol, cell lysis solution (with and without 1% sodium azide) and dehydration can be used to preserve fresh and partially decomposed soft muscle tissues at room temperature for one year. The drop-out in amplification of larger amplicons in tissues preserved in 10% buffered formalin suggested that formalin was not suitable for long term storage. This system should therefore be considered as an additional method during Disaster victim identification (DVI) work to preserve fresh and partially decomposed samples. This study also suggested that the developed multiplex (4-plex) can be used to assess DNA persistence in human decomposing bodies and in experimental studies.
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Houston, Erin L. "The Effects of Various Laundering Factors On The Recoverability Of DNA." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1472489089.
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Wright, Kirsty. "An Evaluation of the Thai Tsunami Victim Identification DNA Operation." Thesis, Griffith University, 2017. http://hdl.handle.net/10072/367628.2.
Full textAbstract:
On 26 December 2004, a 9.3 magnitude earthquake struck off the west of Sumatra, Indonesia triggering a tsunami that killed over 280,000 people in thirteen countries. The total energy released from the earthquake was equivalent to 550 million times that of the Hiroshima atomic bomb. It was one of the deadliest natural disasters in modern history, and, in terms of scale and number of victims, the largest ever disaster victim identification (DVI) operation. In response, teams of police and forensic experts from around the world united to form the Thai Tsunami Victim Identification (TTVI) operation in Phuket from 12 January 2005 in an unprecedented effort to identify 3,679 victims. Approximately half of the victims were foreign tourists who perished along the popular tourist strip in Thailand. Forensic evidence, including the primary identifiers dental, fingerprints and DNA, were used to compare ante-mortem (AM) and post-mortem (PM) data in accordance with INTERPOL DVI guidelines. The identification effort continues today at the Royal Thai Police Headquarters in Bangkok for approximately 370 unidentified victims.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Natural Sciences
Science, Environment, Engineering and Technology
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Schlecht, Stephen Harold. "A Histomorphometric Analysis of Muscular Insertion Regions: Understanding Enthesis Etiology." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1328985192.
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Terada, Andrea Sayuri Silveira Dias. "Utilização do produto Allprotect Tissue Reagent® na estabilização do DNA extraído de tecidos dentais humanos em diferentes condições de armazenamento." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/58/58137/tde-17052013-110504/.
Full textAbstract:
A metodologia genético-molecular destaca-se como uma técnica apurada para os processos de identificação humana e, dentre as fontes de evidência biológica, o uso de elementos dentais é de grande interesse. A manutenção da integridade do material enviado ao laboratório é imprescindível para o sucesso dos resultados obtidos e uma das principais dificuldades encontradas é com relação ao armazenamento da amostra, que geralmente é realizado em baixas temperaturas. O presente trabalho avaliou a eficácia do produto Allprotect Tissue Reagent® (Qiagen, Hilden, Germany) na estabilização do DNA extraído de tecidos dentais humanos armazenados em diferentes condições. Para tal, foram utilizados 165 elementos dentais, os quais foram distribuídos em dois grupos distintos: dente íntegro e tecido pulpar dental isolado. As amostras foram armazenadas com ou sem a utilização do referido produto, variando o período de tempo (1, 7, 30 e 180 dias) e temperatura (ambiente e refrigeração). Além desses grupos, foi formado um grupo controle positivo composto por cinco elementos dentais armazenados a -20ºC durante 180 dias. Após o armazenamento foi realizada extração do DNA, eletroforese em gel de agarose, quantificação do DNA genômico por PCR Tempo Real e análise de fragmentos de 37 amostras. Os fragmentos de 32 amostras que representavam cada condição possível e as cinco amostras do grupo controle positivo foram analisados, a fim de verificar quatro marcadores pré-selecionados. O gel de agarose mostrou evidências da presença de DNA genômico. Os valores da quantificação foram analisados estatisticamente pelos testes Kruscal-Wallis e Mann-Whitney. Os resultados mostraram valores que variaram de 0,01 a 10246,88ng/L de DNA. Houve diminuição da concentração de DNA nas amostras de dente armazenadas em temperatura ambiente por 30 e 180 dias em relação às que ficaram armazenadas por 1 e 7 dias. Além do fator tempo, a temperatura também influenciou na concentração de DNA, sendo maior nos dentes que ficaram por 30 dias e na polpa dental mantida por 180 dias, quando refrigerados. Em relação à utilização do produto Allprotect Tissue Reagent® (Qiagen, Hilden, Germany), o mesmo mostrou diferença significativa na estabilização dos dentes que foram armazenados em temperatura ambiente durante 30 e 180 dias. A análise de fragmentos foi possível nas 37 amostras selecionadas, independente da quantidade de DNA, confirmando a importância das reações de amplificação e da análise de STR utilizando método automático. Conclui-se que a utilização do produto Allprotect Tissue Reagent® (Qiagen, Hilden, Germany) mostrou diferença significativa na estabilização do DNA das amostras de dentes íntegros armazenadas em temperatura ambiente durante 30 e 180 dias, enquanto que nas demais condições testadas, os resultados não evidenciaram justificativas para o uso do produto.The genetic-molecular methodology stands out as an accurate technique for human identification process and among the sources of biological evidence, the use of teeth is of great interest in Forensic Dentistry. Maintaining integrity of the material sent to laboratory is essential for success of the analysis, and one of the main difficulties is related to sample storage, which is usually carried out at low temperatures. This study evaluated the effectiveness of the Allprotect Tissue Reagent® (Qiagen, Hilden, Germany) in stabilizing DNA extracted from human dental tissues stored under different conditions. In this study were used 165 teeth, distributed in two groups: intact teeth and isolated pulp tissue. The samples were stored with or without the product and varying the storage time (1, 7, 30 and 180 days) and temperature (room temperature and under refrigeration). In addition to these groups, was formed a positive control group, composed by five teeth, which was stored at -20ºC for 180 days. After storage, DNA extraction, electrophoresis on agarose gel and genomic DNA quantification by Real-Time PCR and fragments of 37 samples were performed. The fragments of 32 samples representing every possible condition and five positive control group samples were analyzed to verify four pre-selected markers. The agarose gel showed evidences of genomic DNA presence. Quantification results were statistically analyzed with the tests Kruscal-Wallis and Mann-Whitney. Quantification results showed values ranging from 0.01 to 10,246.88 ng/L of DNA. There was a decrease in DNA concentration in stored tooth samples at room temperature for 30 and 180 days compared to those stored for 1 and 7 days. Besides the time factor, temperature also influenced the DNA concentration, being higher in teeth that remained for 30 days and in tooth pulp maintained for 180 days, under refrigeration. Regarding the use of Allprotect Tissue Reagent® (Qiagen, Hilden, Germany) it showed a significant difference in stabilization of stored teeth at room temperature for 30 and 180 days. The analysis of fragments was possible in 37 selected samples, regardless of the DNA quantity variation, confirming that amplification reactions and STR analysis using automated methods provides good results. It was concluded that the use of Allprotect Tissue Reagent® (Qiagen, Hilden, Germany) showed a significant difference in stabilizing DNA samples of intact human teeth stored at room temperature for 30 and 180 days, while in the other test conditions the results showed no justification for using this product.
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Muharam, Firman Alamsyah. "Overcoming problems with limiting DNA samples in forensics and clinical diagnostics using multiple displacement amplification." Thesis, Queensland University of Technology, 2006. https://eprints.qut.edu.au/16207/1/Firman_Muharam_Thesis.pdf.
Full textAbstract:
The availability of DNA samples that are of adequate quality and quantity is essential for any genetic analysis. The fields of forensic biology and clinical diagnostic pathology testing often suffer from limited samples that yield insufficient DNA material to allow extensive analysis. This study examined the utility of a recently introduced whole genome amplification method termed Multiple Displacement Amplification (MDA) for amplifying a variety of limited sample types that are commonly encountered in the fields of forensic biology and clinical diagnostics. The MDA reaction, which employs the highly processive bacteriophage φ29 DNA polymerase, was found to generate high molecular weight template DNA suitable for a variety of downstream applications from low copy number DNA samples down to the single genome level. MDA of single cells yielded sufficient DNA for up to 20,000,000 PCR assays, allowing further confirmatory testing on samples of limited quantities or the archiving of precious DNA material for future work. The amplification of
degraded DNA material using MDA identified a requirement for samples of sufficient quality to allow successful synthesis of product DNA templates. Furthermore, the utility of MDA products in comparative genomic hybridisation
(CGH) assays identified the presence of amplification bias. However, this bias was overcome by introducing a novel modification to the MDA protocol. Future directions for this work include investigations into the utility of MDA products in short tandem repeat (STR) assays for human identifications and application of the modified MDA protocol for testing of single cell samples for genetic abnormalities.
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Muharam, Firman Alamsyah. "Overcoming problems with limiting DNA samples in forensics and clinical diagnostics using multiple displacement amplification." Queensland University of Technology, 2006. http://eprints.qut.edu.au/16207/.
Full textAbstract:
The availability of DNA samples that are of adequate quality and quantity is essential for any genetic analysis. The fields of forensic biology and clinical diagnostic pathology testing often suffer from limited samples that yield insufficient DNA material to allow extensive analysis. This study examined the utility of a recently introduced whole genome amplification method termed Multiple Displacement Amplification (MDA) for amplifying a variety of limited sample types that are commonly encountered in the fields of forensic biology and clinical diagnostics. The MDA reaction, which employs the highly processive bacteriophage φ29 DNA polymerase, was found to generate high molecular weight template DNA suitable for a variety of downstream applications from low copy number DNA samples down to the single genome level. MDA of single cells yielded sufficient DNA for up to 20,000,000 PCR assays, allowing further confirmatory testing on samples of limited quantities or the archiving of precious DNA material for future work. The amplification of degraded DNA material using MDA identified a requirement for samples of sufficient quality to allow successful synthesis of product DNA templates. Furthermore, the utility of MDA products in comparative genomic hybridisation (CGH) assays identified the presence of amplification bias. However, this bias was overcome by introducing a novel modification to the MDA protocol. Future directions for this work include investigations into the utility of MDA products in short tandem repeat (STR) assays for human identifications and application of the modified MDA protocol for testing of single cell samples for genetic abnormalities.
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Morgan, Brittany. "Development of Micro Volume DNA and RNA Profiling Assays to Identify the Donor and Tissue Source of Origin of Trace Forensic Biological Evidence." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6326.
Full textAbstract:
In forensic casework analysis it is necessary to obtain genetic profiles from increasingly smaller amounts of biological material left behind by perpetrators of crime. The ability to obtain profiles from trace biological evidence is demonstrated with so-called 'touch DNA evidence' which is perceived to be the result of DNA obtained from shed skin cells transferred from donor to an object or person during physical contact. However, the current method of recovery of trace DNA involves cotton swabs or adhesive tape to sample an area of interest. This "blind-swabbing" approach may result in the recovery of biological material from different individuals resulting in admixed DNA profiles which are often difficult to interpret.
Profiles recovered from these samples are reported to be from shed skin cells with no biological basis for that determination. A specialized approach for the isolation of single or few cells from 'touch DNA evidence' is necessary to improve the analysis and interpretation of recovered profiles. Here we describe the development of optimized and robust micro volume PCR reactions (1-5 uL) to improve the sensitivity and efficiency of 'touch DNA' analysis. These methods will permit not only the recovery of the genetic profile of the donor of the biological material, but permit an identification of the tissue source of origin using mRNA profiling.
Results showed that the 3.5 uL amplification volume, a fraction of the standard 25 uL amplification volume, was the most ideal volume for the DNA assay, as it had very minimal evaporation with a 50% profile recovery rate at a single cell equivalent input (~5 pg) with reducing amplification volume alone. Findings for RNA showed that by reducing both amplification steps, reverse transcriptase PCR (20 uL) and body fluid multiplex PCR (25 uL), to 5 uL, ideal results were obtained with an increase in sensitivity and detection of six different body fluids down to 50 pg.
Once optimized at the trace level, the assays were applied to the collection of single and few cells. DNA findings showed that about 40% of a full profile could be recovered from a single buccal cell, with nearly 80% of a full profile recovered from only two cells. RNA findings from collected skin particles of "touched" surfaces showed accurate skin detection down to 25 particles and detection in one clump of particles. The profiles recovered were of high quality and similar results were able to be replicated through subsequent experiments.
More studies are currently underway to optimize these developed assays to increase profile recovery at the single cell level. Methods of doing so include comparing different locations on touched surfaces for highest bio-particle recovery and the development of physical characteristics of bio-particles that would provide the most ideal results.M.S.
Masters
Chemistry
Sciences
Forensic Science; Forensic Biochemistry Track
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Moreno, Lilliana I. "The Effect of Sample and Sample Matrix on DNA Processing: Mechanisms for the Detection and Management of Inhibition in Forensic Samples." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/1764.
Full textAbstract:
The presence of inhibitory substances in biological forensic samples has, and continues to affect the quality of the data generated following DNA typing processes. Although the chemistries used during the procedures have been enhanced to mitigate the effects of these deleterious compounds, some challenges remain. Inhibitors can be components of the samples, the substrate where samples were deposited or chemical(s) associated to the DNA purification step. Therefore, a thorough understanding of the extraction processes and their ability to handle the various types of inhibitory substances can help define the best analytical processing for any given sample. A series of experiments were conducted to establish the inhibition tolerance of quantification and amplification kits using common inhibitory substances in order to determine if current laboratory practices are optimal for identifying potential problems associated with inhibition. DART mass spectrometry was used to determine the amount of inhibitor carryover after sample purification, its correlation to the initial inhibitor input in the sample and the overall effect in the results. Finally, a novel alternative at gathering investigative leads from samples that would otherwise be ineffective for DNA typing due to the large amounts of inhibitory substances and/or environmental degradation was tested. This included generating data associated with microbial peak signatures to identify locations of clandestine human graves. Results demonstrate that the current methods for assessing inhibition are not necessarily accurate, as samples that appear inhibited in the quantification process can yield full DNA profiles, while those that do not indicate inhibition may suffer from lowered amplification efficiency or PCR artifacts. The extraction methods tested were able to remove >90% of the inhibitors from all samples with the exception of phenol, which was present in variable amounts whenever the organic extraction approach was utilized. Although the results attained suggested that most inhibitors produce minimal effect on downstream applications, analysts should practice caution when selecting the best extraction method for particular samples, as casework DNA samples are often present in small quantities and can contain an overwhelming amount of inhibitory substances.
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Carlin, Michelle. "Development and evaluation of an LC-ESI-MS method for the simultaneous detection of five major opium alkaloids." Thesis, Northumbria University, 2015. http://nrl.northumbria.ac.uk/27317/.
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The aim of this work was to establish an analytical method for the simultaneous detection of five major opium alkaloids in poppy seeds by liquid chromatography-electrospray ionisation-mass spectrometry (LC-ESI-MS). Once opium alkaloids were detected in poppy seeds, toxicological studies were carried out to establish if these compounds were detected in oral fluid (OF) of participants who ingested muffins containing poppy seeds. It is known that the ingestion of poppy seeds has caused positive opiate drug test results and much work has been reported in the scientific literature in the last 20 years. Researchers in the field have investigated alternatives to differentiate between heroin administration and that of other opiate drugs versus poppy seed ingestion. Most of the work which has been carried out relates to establishing illicit heroin use by examining biological matrices for the presence of acetylcodeine, thebaine, papaverine, noscapine and their associated metabolites. The research methodology consisted of establishing an LC-ESI-MS method for the simultaneous detection of five major opium alkaloids (morphine, codeine, thebaine, papaverine and noscapine). A deuterated internal standard (morphine-d3) was used for the quantitation of alkaloids in harvested poppy seeds and oral fluid samples. Due to technical difficulties, 3 LC-MS instruments were employed in this work. Electrospray ionisation was employed in all mass spectrometers but the analysers included an ion trap with octopole, a triple quadrupole and a hybrid quadrupole Orbitrap. Suitable extraction procedures were determined and harvested seeds purchased from a number of supermarkets were analysed for the presence of five alkaloid compounds using the LC-MS method. A small scale pilot study with 6 participants was carried out to establish if it was possible to fail an OF drug test for opiates after consuming poppy seed muffins. OF samples were collected post ingestion using Quantisal™ kits and the level of each of the opiates was monitored. The findings were that an LC-ESI-MS method was established for the simultaneous detection and quantitation of five major alkaloids. However, the method development process involved finding a solution to co-elution of morphine and codeine. The process also included resolving the issue of thebaine producing two peaks with identical mass spectra and separated by a difference of 6 minutes in retention time. Varying levels of alkaloids were identified in harvested poppy seeds: levels of these compounds differed considerably within and between batches of poppy seeds. These findings could be attributed to a number of factors, for example, where and how the plants were grown and methods of harvesting. Two poppy seed muffins were consumed as part of a toxicology study. Morphine was detected in the 5 minute sample in 5 out of the 6 participants with concentrations in OF of 0.5-0.8 ng mL-1; codeine was detected in 2 of the 6 participants at 1.5 and 2.6 ng mL-1. Thebaine, noscapine and papaverine were also detected in OF of a number of participants, which has not been previously reported in the literature. However, it should be noted that the values calculated are only estimated since the peak area ratios obtained were found to be less than the lowest concentration (10 ng mL-1) in the linear calibration range. In conclusion, an LC-ESI-MS method for the simultaneous detection and quantitation of five major opium alkaloids has been established and has been used to detect alkaloids in harvested poppy seeds and oral fluid samples. From a small pilot toxicology study, oral fluid results indicate that levels of morphine and codeine do not exceed the SAMSHA 40 ng mL-1 cut-off after ingestion of a realistic amount of poppy seeds contained within bakery products.
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Wehri, Elizabeth G. "A Classification System of Osteomyelitis for Historic Skeletal Remains: An Assessment of Civil War Soldier Amputees." Cincinnati, Ohio : University of Cincinnati, 2009. http://rave.ohiolink.edu/etdc/view.cgi?acc_num=ucin1243015132.
Full textAbstract:
Thesis (M.A.)--University of Cincinnati, 2009.Advisor: Alan P. Sullivan. Title from electronic thesis title page (viewed Aug. 27, 2009). Includes abstract. Keywords: Osteomyelitis; Civil War; Paleopathology; Osteology. Includes bibliographical references.
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Seashols, Sarah. "Variation and Modulation of microRNAs in Prostate Cancer and Biological Fluids." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3258.
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Prostate cancer is the second-most diagnosed and fatal carcinoma for males in the United States, and better diagnostic markers and potential therapies are needed. microRNAs are small, single-stranded RNA molecules that affect protein expression at the translational level, and dysregulation can dramatically affect cell metabolism. Comparison of 736 microRNA expression levels between the poorly metastatic SV40T immortalized prostate epithelial cell line P69 to its highly tumorigenic and metastatic subline M12 identified 231 miRs that were overexpressed and 150 miRs that showed loss of expression in the M12 cell line. Further evaluation of fourteen identified miRs was accomplished using other prostate cell lines as well as laser-capture microdissected prostate samples. Inhibition of miR-147b was found to affect proliferative, migratory and invasive capabilities of M12 cells, and reduced tumour growth in nude athymic mice. AATF, an activator of the cell-cycle inhibitor p21, was identified as a target. Overexpression of miR-9 was found to affect the epithelial to mesenchymal transition through suppression of e-cadherin, a protein characterized as lost in EMT, as well as suppression of SOCS5, an attenuator of JAK-STAT signaling. Inhibition of miR-9 resulted in reduction of migratory and invasive potential, and significant reduction of tumorigenesis and metastases in male nude athymic mice. miR-17-3p was previously identified as down-regulated in prostate cancer and loss of miR-17-3p shown to cause vimentin transcriptional activation. Reverse phase microarray analysis (RPMA) identified c-KIT as a potential second mRNA target for miR-17-3p. miR-17-3p was shown to modulate not only protein levels, but also messenger RNA levels of c-KIT. Four miR-17-3p binding sites in the c-KIT mRNA were identified. Thus, a number of microRNAs involved in prostate cancer were identified, and their targets found to be highly relevant to tumour progression and could potentially be used as targets for therapy or diagnostics. Stability of microRNAs in forensically relevant biological fluids was evaluated through heat treatment, ultraviolet radiation, and chemical treatment. The dried body fluids showed some susceptibility to harsh treatment, but in most cases microRNAs were still detectable in the samples. microRNAs could represent a highly stable species for body fluid identification methods in forensic science.
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Maybruck, Julie Lauren. "The identification and characterization of new y-chromosome short tandem repeat LOCI and a closer look at the YpXq 3-4mb homology block." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1085600591.
Full textAbstract:
Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xi, 133 p.; also includes graphics Includes bibliographical references (p. 127-133). Available online via OhioLINK's ETD Center
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Zirkle, Dexter. "The Development of the Anterior Inferior Iliac Spine: A Comparative Analysis Among Hominids and African Apes." Kent State University / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=kent1427206046.
Full text
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Doll, Laura Catherine. "An investigation of genetic variability in Lucilia cuprina and Musca domestica utilizing phylogenetic and population genetic approaches." Thesis, 2020. http://hdl.handle.net/1805/23349.
Full textAbstract:
Indiana University-Purdue University Indianapolis (IUPUI)Forensic entomology is a subdiscipline of entomology that involves the use of insect behavior and developmental data to aid in criminal investigations. Genetic data has become increasingly important to the field as there has been a push for DNA-based species identification methods of forensically relevant insects. Genetic data can also elucidate population structure and relatedness of these insects, and such knowledge can contribute to the development of more specific datasets for insects in different regions. The first study presented here investigated the phylogenetics of sister species Lucilia cuprina and Lucilia sericata to identify possible subspecies divisions and issues with DNA-based identifications in the United States. The initial aim of this study was to identify genetic differences between specimens of L. cuprina that preferred live versus carrion flesh. Flies collected from Indiana, USA and South Africa were sequenced and analyzed. Upon sequencing of the genes COI, Period, and 28s, our results indicated that L. cuprina from Indiana possess a unique combination of nuclear and mitochondrial haplotypes that suggest a unique lineage, possibly indicating modern hybridization with L. sericata. The inability of both nuclear and mitochondrial genes to distinguish between L. cuprina and L. sericata raises questions about the capabilities of DNA-based species identifications within this genus. Additionally, the inability of these genes to distinguish between specimens that preferred live versus carrion flesh highlights a need for continued research of these behavioral differences. The second study presented here investigated the population structure and relatedness of house flies in the American southwest in relation to a civil lawsuit where neighbors of a poultry farm alleged that flies were emanating from the farm to their homes. Musca domestica (house fly) specimens were collected from the chicken farm and from locations in varying directions and distances from the farm. Amplified fragment length polymorphism (AFLP) analysis was performed and the data were used in a number of analyses. Population reallocation simulations generally indicated that samples from different locations were not genetically different enough from other locations to allocate to their true origin population over others. Kinship analysis showed differences in samples collected in a later season that indicate a genetic bottleneck over time. Population structure analysis indicated the presence of two intermixing genetic populations in the dataset. AMOVA revealed that the majority of genetic variation laid within, rather than among, populations. A Mantel test revealed no significant correlation between genetic and geographic distances. These results indicate that the M. domestica population in this region of southwestern America is large and intermixing, with no clear genetic distinctions between specimens collected at the poultry farm versus the surrounding locations. In regard to the civil lawsuit, it was not possible to conclude that the flies did not emanate from the poultry farm. In a broader perspective, these data can be utilized to develop pest management strategies in this region. Overall, the data from both studies presented here will be useful to forensic investigations, development of more specific and detailed data and identification techniques, and pest control measures.
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Zeng, SiYang. "Brief Introduction to Forensic Science and Forensic in Australia and China." Master's thesis, 2019. http://hdl.handle.net/10316/95583.
Full textAbstract:
Documentos apresentados no âmbito do reconhecimento de graus e diplomas estrangeirosFinding the justice for judicial system by using scientific method analysis to deal with crime issue is the reason why forensic science exist. By collecting and analysis evidence from crime scene, forensic science is able to detect the truth behind of crime scene, which it helps judge and jury in the court of the law to evaluate someone’s innocent or guilty. There is a fact that forensic science firmly relies on law system no matter which countries they are or what kind of law systems they have around the world. In other words, forensic science in different counties which have different law systems might have different forensic history, subjects or strategy. However, even the law systems can be different, the gap between different systems of forensic science are bridging less and less. Following the speeding trend of economic globalization, forensic science also cannot avoid being influenced by this tide, especially for forensic standard sharing and research cooperation (Lucas, D. 2011). The International Association of Forensic Sciences (IAFS) was established by 6 countries (the United Kingdom, the United States, Switzerland, Belgium, Denmark and Canada) to share forensic information of English language every three years globally (Lucas, D. 2011). Until 2011, there were ready 109 countries attending the IAFS meeting to exchange forensic knowledge and research (Lucas, D. 2011).
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Calle, Sergio. "A geometric morphometric analysis of contemporary Hispanic populations from Mexico and Colombia." Thesis, 2020. https://hdl.handle.net/2144/39423.
Full textAbstract:
In contexts such as natural disasters, humanitarian efforts, and other forensic investigations, the timely and accurate development of the biological profile (sex, age, ancestry, and stature of skeletonized remains) is vital to the identification of decedents. At present, the term “Hispanic” is a socio-linguistic classifier that includes all persons of South or Central American, Mexican, Cuban, Puerto Rican, or other Latino and Spanish-speaking persons into a single category; the term is also the current designator used by forensic anthropologists—in ancestry estimation—to identify anyone from a Latin American country. From a biological standpoint, the term is ineffective in describing these individuals because the human biological variation within and among different Hispanic populations cannot be encompassed by a single category. With regards to the development of the biological profile, ancestry estimations for these individuals are tenuous at best. This is due to the poor nature of the single reference sample used to create the current methods in ancestry and sex estimation—a common trend in forensic anthropology. The untested assumption that all Hispanic individuals are skeletally homogenous results in haphazard identifications and hinders effective forensic investigation.
The primary objective of this research is to examine geometric morphometric variability in 547 documented individuals from three contemporaneous Latin American groups represented by Colombian, Mexican, and Migrant (U.S./Mexico border crossers) samples in order to ascertain whether it is possible to distinguish specific Hispanic populations. Using geometric morphometric (GM) analyses, the effects of shape-related variation independent of size can be implemented to isolate where on the cranium differences between groups are expressed.
The results suggest that GM-derived population-specific criteria for Hispanic individuals possess the discriminatory power that is necessary towards improving the underdeveloped methods of identification for diverse Hispanic individuals living in the U.S. and abroad. Canonical variate analyses of the three samples separates the groups distinctly along both axes (CV1 and CV2). The morphological differences are predominantly seen in cranial height and sagittal vault shape, with Colombians having taller cranial vaults than the Mexican samples.
The final results of this study demonstrate the utility that GM approaches have in forensic anthropology with respect to ancestry estimation and can be used to update various techniques required to develop the biological profile. Without constantly updating, refining, and re-validating the techniques, forensic anthropologists fail to provide the caliber of service required to approach the various forensic contexts.
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Dembinski, Gina M. "Advancements in forensic DNA-based identification." Thesis, 2017. https://doi.org/10.7912/C2BQ0S.
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Indiana University-Purdue University Indianapolis (IUPUI)Modern DNA profiling techniques have increased in sensitivity allowing for higher success in producing a DNA profile from limited evidence sources. However, this can lead to the amplification of more DNA profiles that do not get a hit on a suspect or DNA database and more mixture profiles. The work here aims to address or improve these consequences of current DNA profiling techniques. Based on allele-specific PCR and quantitative color measurements, a 24-SNP forensic phenotypic profile (FPP) assay was designed to simultaneously predict eye color, hair color, skin color, and ancestry, with the potential for age marker incorporation. Bayesian Networks (BNs) were built for model predictions based on a U.S sample population of 200 individuals. For discrete pigmentation traits using an ancestry influenced pigmentation prediction model, AUC values were greater than 0.65 for the eye, hair, and skin color categories considered. For ancestry using an all SNPs prediction model, AUC values were greater than 0.88 for the 5 continental ancestry categories considered. Quantitative pigmentation models were also built with prediction output as RGB values; the average amount of error was approximately 7% for eye color, 12% for hair color, and 8% for skin color. A novel sequencing method, methyl-RADseq, was developed to aid in the discovery of candidate age-informative CpG sites to incorporate into the FPP assay. There were 491 candidate CpG sites found that either increased or decreased with age in three forensically relevant xii fluids with greater than 70% correlation: blood, semen, and saliva. The effects of exogenous microbial DNA on human DNA profiles were analyzed by spiking human DNA with differing amounts of microbial DNA using the Promega PowerPlex® 16 HS kit. Although there were no significant effects to human DNA quantitation, two microbial species, B. subtilis and M. smegmatis, amplified an allelic artifact that mimics a true allele (‘5’) at the TPOX locus in all samples tested, interfering with the interpretation of the human profile. Lastly, the number of contributors of theoretically generated 2-, 3-, 4-, 5-, and 6-person mixtures were evaluated via allele counting with the Promega PowerPlex® Fusion 6C system, an amplification kit with the newly expanded core STR loci. Maximum allele count in the number of contributors for 2- and 3-person mixtures was correct in 99.99% of mixtures. It was less accurate in the 4-, 5-, and 6-person mixtures at approximately 90%, 57%, and 8%, respectively. This work provides guidance in addressing some of the limitations of current DNA technologies.
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Carter, Megan Elizabeth. "Blood on FTA™ Paper: Does Punch Location Affect the Quality of a Forensic DNA Profile?" 2013. http://hdl.handle.net/1805/3244.
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Indiana University-Purdue University Indianapolis (IUPUI)Forensic DNA profiling is widely used as an identification tool for associating an individual with evidence of a crime. Analysis of a DNA sample involves observation of data in the form of an electropherogram, and subsequently annotating a DNA “profile” from an individual or from the evidence. The profile obtained from the evidence can be compared to reference profiles deposited in a national DNA database, which may include the potential contributor. Following a match, a random match probability is calculated to determine how common that genotype is in the population. This is the probability of obtaining that same DNA profile by sampling from a pool of unrelated individuals. Each state has adopted various laws requiring suspects and/or offenders to submit a DNA sample for the national database (such as California’s law that all who are arrested must provide a DNA sample). These profiles can then be associated with past unsolved crimes, and remain in the database to be searched in the event of future crimes. In the case of database samples, a physical sample of the offender’s DNA must be kept on file in the laboratory indefinitely so that in the event of a database hit, the sample is able to be retested. Current methods are to collect a buccal swab or blood sample, and store the DNA extracts under strict preservation conditions, i.e. cold storage, typically -20° C. With continually increasing number of samples submitted, a burden is placed on crime labs to store these DNA extracts. A solution was required to help control the costs of properly storing the samples. FTA™ paper was created to fulfill the need for inexpensive, low maintenance, long term storage of biological samples, which makes it ideal for use with convicted offender DNA samples. FTA™ paper is a commercially produced, chemically treated paper that allows DNA to be stored at room temperature for years with no costly storage facilities or conditions. Once a sample is required for DNA testing, a small disc is removed and is to be used directly in a PCR reaction. A high quality profile is important for comparing suspect profiles to unknown or database profiles. A single difference between a suspect and evidentiary sample can lead to exclusion. Unfortunately, the DNA profile results yielded from the direct addition have been unfavorable. Thus, most crime laboratories will extract the DNA from the disc, leading to additional time and cost to analyze a reference sample. Many of the profiles from the direct addition of an FTA™ disc result in poor quality profiles, likely due to an increase in PCR inhibitors and high concentrations of DNA. Currently, standardized protocols regarding the recommended locations for removal of a sample disc from a bloodspot on an FTA™ card does not exist. This study aims to validate the optimal location by comparing DNA profiles obtained from discs removed from the center, halfway, and edge locations of a bloodspot from 50 anonymous donors. Optimal punch location was first scored on the number of failed, partial or discordant profiles. Then, profile quality was determined based on peak characteristics of the resulting DNA profiles. The results for all three disc locations were 5.3% failed amplifications, 4.2% partial amplifications, and one case of a discordant profile. Profile quality for the majority of the samples showed a high incidence of stutter and the absence of non-template adenylation. Of the three disc locations, the edge of the blood stain was ideal, due to a presumably lower concentration of DNA and likely more dilute amount of the PCR inhibitor heme. Therefore, based on the results of this study, there is a greater probability of success using a sample from the edge of a blood stain spotted in FTA™ paper than any other location of the FTA™ card.
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Breslin, Krystal. "Forensic DNA phenotyping and massive parallel sequencing." Thesis, 2017. https://doi.org/10.7912/C29D3H.
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Indiana University-Purdue University Indianapolis (IUPUI)In the forensic science community, there is an immense need for tools to help assist investigations where conventional DNA profiling methods have been non-informative. Forensic DNA Phenotyping (FDP) aims to bridge that gap and aid investigations by providing physical appearance information when other investigative methods have been exhausted. To create a “biological eye witness”, it becomes necessary to constantly improve these methods in order to develop a complete and accurate image of the individual who left the sample. To add to our previous prediction systems IrisPlex and HIrisPlex, we have developed the HIrisPlex-S system for the all-in-one combined prediction of eye, hair, and skin color from DNA. The skin color prediction model uses 36 variants that were recently proposed for the accurate prediction of categorical skin color on a global scale, and the system is completed by the developmental validation of a 17-plex capillary electrophoresis (CE) genotyping assay that is run in conjunction with the HIrisPlex assay to generate these genotypes. The predicted skin color output includes Very Pale, Pale, Intermediate, Dark and Dark-to-Black categories in addition to categorical eye (Blue, Intermediate, and Brown) and hair (Black, Brown, Blond, and Red) color predictions. We demonstrate that the HIrisPlex-S assay performs in full agreement with guidelines from the Scientific Working Group on DNA Analysis Methods (SWGDAM), achieving high sensitivity levels with a minimum 63pg DNA input. In addition to adding skin color to complete the pigmentation prediction system termed HIrisPlex-S, we successfully designed a Massively Parallel Sequencing (MPS) assay to complement the system and bring Next Generation Sequencing (NGS) to the forefront of forensic DNA analyses methods. Using Illumina’s MiSeq system enables the generation of HIrisPlex-S’s 41 variants using sequencing data that has the capacity to xiii better deconvolute mixtures and perform with even more sensitivity and accuracy. This transition opens the door for a plethora of new ways in which this physical appearance assay can grow as sequencing technology is not limited by variant number; therefore, in essence many more traits have the potential to be included in this one assay design. For now, the HIrisPlex-S design of 41 variants using MPS is being fully assessed according to SWGDAM validated guidelines; therefore, this design paves the way for Forensic DNA Phenotyping to be used in any forensic laboratory. This new and improved HIrisPlex-S system will have a profound impact on casework, missing persons cases, and anthropological cases, as it is relatively inexpensive to run, HIrisPlex-S is easy to use, developmentally validated and one of the largest systems freely available online for physical appearance prediction from DNA using the freely available online web tool found at https://hirisplex.erasmusmc.nl/. Lastly, moving forward in our aim to include additional traits for prediction from DNA, we contributed to a large-scale research collaboration to unearth variants associated with hair morphology. 1026 samples were successfully sequenced using an inhouse MPS design at 91 proposed hair morphological loci. From this reaction, we were able to contribute to the identification of significant correlations between the SNPs rs2219783, rs310642 and rs80293268 with categorical hair morphology: straight, wavy or curly.
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Tine, Emily Marion. "Ninhydrin as a universal screening tool for body fluids." Thesis, 2014. https://hdl.handle.net/2144/15318.
Full textAbstract:
Ninhydrin is one of the most widely used chemical reagents for the enhancement of latent fingerprint impressions on porous substrates^1-22. Ninhydrin (2,2-dihydroxyindane-1,3-dione) reacts with the amino acids most commonly encountered in the sweat of fingerprints, producing an intense purple color^1. Since ninhydrin reacts with amino groups in organic compounds, the chemical ought to be able to positively react with biological materials collected at crime scenes that contain amino acids associated with the nucleic acids in DNA^1,21.
Previous studies have investigated the use of ninhydrin as a screening tool for specific types of biological material^21,22. Driscoll et al. has found that treating buccal swabs with ninhydrin has greatly assisted in locating the buccal cells for subsequent DNA analysis^22. Bayer et al. has shown that ninhydrin can be an effective screening method of swabs containing an unknown content of biological material and can detect cellular material on handled items^21. In addition, ninhydrin has repeatedly been shown to have minimal effect on DNA and downstream PCR processes^16,21,22.
Present methods for body fluid identification test for only one body fluid at a time, i.e. identifying three different body fluids would require that three different assays be employed. Pre-screening certain items with ninhydrin could assist crime scene investigators in collecting the most probative samples, rather than randomly selecting from items that may or may not contain any biological material. Ninhydrin is inexpensive, easy to use and has the potential to be an effective screening tool for various types of biological material. Additionally, a tool that encompasses various types of biological materials is beneficial to crime scene investigators by minimizing the resources needed and providing a broader situational use.
In this study, the capability of ninhydrin to react with dilute blood, neat semen, neat saliva, vaginal secretions, neat urine and perspiration was determined. In addition, the efficacy of various methods for processing and developing the ninhydrin reaction as well as the effectiveness of ninhydrin as a screening tool on various substrates were explored. Furthermore, the effect of ninhydrin on subsequent presumptive and confirmatory body fluid testing was examined.
The results show that ninhydrin can successfully enhance latent blood, semen, saliva, vaginal secretions, urine and perspiration. Different substrates affected the visualization of ninhydrin-processed stains, thus the type of substrate should be considered when using ninhydrin, and methods may need to be adjusted accordingly. Further, ninhydrin processing does not appear to detrimentally affect subsequent presumptive and confirmatory screening for blood, semen and urine. Saliva testing results were inconsistent and must be further studied to determine whether or not ninhydrin negatively affects the outcome of these tests.
Not all stains that reacted positively with ninhydrin were body fluids. Whole milk, beer, Red Bull® and Naked Juice protein smoothie all showed a purple color change when processed with ninhydrin. The best ninhydrin solvent overall was determined to be HFE7100 due to its cleaner application and more consistent results than petroleum ether. The use of a steam iron may detrimentally impact secondary screening of body fluids; suspected body fluids should be processed with ninhydrin in a laboratory oven at approximately 70℃ to prevent potential loss of evidence.
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Yearwood-Garcia, Xia Marie. "DNA signal variability and its impact on forensic DNA interpretation and quantification." Thesis, 2017. https://hdl.handle.net/2144/26951.
Full textAbstract:
The increased sensitivities of recently developed polymerase chain reaction (PCR) and separation techniques have afforded forensic deoxyribonucleic acid (DNA) analysts an opportunity to detect low template deoxyribonucleic acid (LT-DNA) samples. However, with LT-DNA samples stochastic effects become more prevalent, compromising the reliability and robustness of these techniques. In addition, these innovations have presented analysts with an increased incidence of higher-order mixtures. These types of mixtures, confounded by LT-DNA effects, continue to test the interpretation step of the DNA analysis pipeline. The combination of allele drop-out, allele drop-in and allele sharing create such complex samples that it necessitates the transition from traditional, threshold-based, interpretational methods to a probabilistic approach. Therefore, this study has two objectives: 1) to optimize the computational tool NOCIt, designed to provide a probability distribution on the number of contributors (NOC) to a sample and 2) to investigate the source of the variability present in quantitative real-time polymerase chain reaction (qPCR) in hopes of minimizing variations observed when determining the quantity of an unknown DNA sample.
The NOCIt graphical user interface (GUI) was validated during its developmental phase. With no current forensic guidelines for the validation of computational tools, the protocol was designed based on a guide developed by the Center for Devices and Radiological Health for the Food and Health Administration (FDA). The protocol required using a variety of test types and detailed documentation of the methods used, the inputs, outputs and results. A total of 325 tests were completed across 11 different software distributions.
As a critical software system, NOCIt’s settings also had to be optimized because of its ability to substantially influence the interpretation, the statistical conclusions and the accuracy of the results. Two different settings (Condition 3 and Condition 4) were tested on AmpFlstr® Identifiler® Plus and PowerPlex® 16 HS PCR amplified samples. The differences between the two conditions were the parameter Number of Samples in Batch and the Multiplicative Factor. All other settings were kept the same. The reproducibility and accuracy were examined to determine which condition was more reliable. Both settings had similar results, with both performing better in different categories.
As with interpretation, quantification is an integral part of the human identification pipeline. Previous studies have shown that the Quantifiler® recommended protocol of generating a standard curve for every quantification (referred to in this study as the Recommended Method) introduces additional sources of variability compared to protocols that utilize one, external, validated curve (referred to in this study as the Experimental Method). To identify the major source of variability inherent in the quantitative polymerase chain reaction (qPCR) process, these two methods of determining the quantity of a DNA sample were investigated using the Quantifiler® Duo and Quantifiler® Trio DNA Quantification assays. Four tenfold serial dilutions were quantified in five independent runs using the Quantifiler® Duo DNA Quantification kit and five independent runs using the Quantifiler® Trio DNA Quantification kit. Quantification with Quantifiler® Duo reported less variability using the Experimental Method than the Recommended Method. Conversely, quantification with Quantifiler® Trio exhibited approximately equal variability between both methods.
To assess whether the errors associated with generating a calibration played a substantive role in introducing additional variability, the test samples were also quantified using digital polymerase chain reaction (dPCR). The data for the more dilute samples were indistinguishable from the noise associated with the instrument. The more concentrated samples showed less variability than the samples quantified with Quantifiler® Duo and approximately the same as those amplified with Quantifiler® Trio. This suggests that both qPCR and dPCR processes can be used to quantify DNA amounts, however, fundamental differences in the ways each determines the values suggests that noise is an inherent and measurable part of dPCR. Thus, for purposes of DNA quantification signal thresholds will need to be determined prior to implementation.
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(7037951), Rebecca F. Lakatos. "Examining the Potential Use of Fungi in Forensic Science." Thesis, 2019.
Find full textAbstract:
Forensic science has gained popularity in the last few decades. Many new techniques are being studied and implemented. It includes a wide range of scientific disciplines, such as entomology, physics and biology. An important improvement to forensic science is the development of different DNA techniques which are implemented during an investigation, making DNA a gold standard for forensics. Most of the time DNA is mentioned it is in terms of human DNA, but there are microscopic organisms with useful DNA. In the last decade, with the development of next-generation sequencing (NGS), studies focusing on bacterial communities have been published, but fungal communities have not been extensively studied.
For this project, the potential of fungi in forensic science was investigated through three different studies. Human flora was looked at by NGS from thirty-seven human bodies with differing post-mortem intervals (PMIs). The communities were analyzed statistically and quantitatively, resulting in unique operational taxonomic units (OTUs) and genera which were only present in certain PMIs, and in some which were present through the entire PMI time scale. These attributes can help, not only to give a better view on human mycoflora during decomposition, but they can also help in determining fungal signatures during decomposition. These signatures can help in a PMI determination. Moreover, swine carcasses – the model animals for human forensic studies – were investigated as well to create a checklist of fungal flora after five months of winter decomposition in the West Lafayette, Indiana area. Furthermore, due to the increased importance of wildlife forensics, a wildlife study was also conducted using four wildlife species (mute swan, red tailed hawk, river otter, bobcat). The fungal flora from these species were compared within species at the beginning of the study and at skeletonization stage to look at any indicator fungal species and to create a general checklist for wildlife studies in the West Lafayette, Indiana area for future studies. Additionally, the fungal communities were compared across species as well.