Sample records for forensic dna databases

  1. Forensic DNA databases in Western Balkan region: retrospectives, perspectives, and initiatives

    PubMed Central

    Marjanović, Damir; Konjhodžić, Rijad; Butorac, Sara Sanela; Drobnič, Katja; Merkaš, Siniša; Lauc, Gordan; Primorac, Damir; Anđelinović, Šimun; Milosavljević, Mladen; Karan, Željko; Vidović, Stojko; Stojković, Oliver; Panić, Bojana; Vučetić Dragović, Anđelka; Kovačević, Sandra; Jakovski, Zlatko; Asplen, Chris; Primorac, Dragan

    2011-01-01

    The European Network of Forensic Science Institutes (ENFSI) recommended the establishment of forensic DNA databases and specific implementation and management legislations for all EU/ENFSI members. Therefore, forensic institutions from Bosnia and Herzegovina, Serbia, Montenegro, and Macedonia launched a wide set of activities to support these recommendations. To assess the current state, a regional expert team completed detailed screening and investigation of the existing forensic DNA data repositories and associated legislation in these countries. The scope also included relevant concurrent projects and a wide spectrum of different activities in relation to forensics DNA use. The state of forensic DNA analysis was also determined in the neighboring Slovenia and Croatia, which already have functional national DNA databases. There is a need for a ‘regional supplement’ to the current documentation and standards pertaining to forensic application of DNA databases, which should include regional-specific preliminary aims and recommendations. PMID:21674821

  2. Forensic DNA databases in Western Balkan region: retrospectives, perspectives, and initiatives.

    PubMed

    Marjanović, Damir; Konjhodzić, Rijad; Butorac, Sara Sanela; Drobnic, Katja; Merkas, Sinisa; Lauc, Gordan; Primorac, Damir; Andjelinović, Simun; Milosavljević, Mladen; Karan, Zeljko; Vidović, Stojko; Stojković, Oliver; Panić, Bojana; Vucetić Dragović, Andjelka; Kovacević, Sandra; Jakovski, Zlatko; Asplen, Chris; Primorac, Dragan

    2011-06-01

    The European Network of Forensic Science Institutes (ENFSI) recommended the establishment of forensic DNA databases and specific implementation and management legislations for all EU/ENFSI members. Therefore, forensic institutions from Bosnia and Herzegovina, Serbia, Montenegro, and Macedonia launched a wide set of activities to support these recommendations. To assess the current state, a regional expert team completed detailed screening and investigation of the existing forensic DNA data repositories and associated legislation in these countries. The scope also included relevant concurrent projects and a wide spectrum of different activities in relation to forensics DNA use. The state of forensic DNA analysis was also determined in the neighboring Slovenia and Croatia, which already have functional national DNA databases. There is a need for a 'regional supplement' to the current documentation and standards pertaining to forensic application of DNA databases, which should include regional-specific preliminary aims and recommendations.

  3. "Would you accept having your DNA profile inserted in the National Forensic DNA database? Why?" Results of a questionnaire applied in Portugal.

    PubMed

    Machado, Helena; Silva, Susana

    2014-01-01

    The creation and expansion of forensic DNA databases might involve potential threats to the protection of a range of human rights. At the same time, such databases have social benefits. Based on data collected through an online questionnaire applied to 628 individuals in Portugal, this paper aims to analyze the citizens' willingness to donate voluntarily a sample for profiling and inclusion in the National Forensic DNA Database and the views underpinning such a decision. Nearly one-quarter of the respondents would indicate 'no', and this negative response increased significantly with age and education. The overriding willingness to accept the inclusion of the individual genetic profile indicates an acknowledgement of the investigative potential of forensic DNA technologies and a relegation of civil liberties and human rights to the background, owing to the perceived benefits of protecting both society and the individual from crime. This rationale is mostly expressed by the idea that all citizens should contribute to the expansion of the National Forensic DNA Database for reasons that range from the more abstract assumption that donating a sample for profiling would be helpful in fighting crime to the more concrete suggestion that everyone (criminals and non-criminals) should be in the database. The concerns with the risks of accepting the donation of a sample for genetic profiling and inclusion in the National Forensic DNA Database are mostly related to lack of control and insufficient or unclear regulations concerning safeguarding individuals' data and supervising the access and uses of genetic data. By providing an empirically-grounded understanding of the attitudes regarding willingness to donate voluntary a sample for profiling and inclusion in a National Forensic DNA Database, this study also considers the citizens' perceived benefits and risks of operating forensic DNA databases. These collective views might be useful for the formation of international common ethical standards for the development and governance of DNA databases in a framework in which the citizens' perspectives are taken into consideration. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  4. The collation of forensic DNA case data into a multi-dimensional intelligence database.

    PubMed

    Walsh, S J; Moss, D S; Kliem, C; Vintiner, G M

    2002-01-01

    The primary aim of any DNA Database is to link individuals to unsolved offenses and unsolved offenses to each other via DNA profiling. This aim has been successfully realised during the operation of the New Zealand (NZ) DNA Databank over the past five years. The DNA Intelligence Project (DIP), a collaborative project involving NZ forensic and law enforcement agencies, interrogated the forensic case data held on the NZ DNA databank and collated it into a functional intelligence database. This database has been used to identify significant trends which direct Police and forensic personnel towards the most appropriate use of DNA technology. Intelligence is being provided in areas such as the level of usage of DNA techniques in criminal investigation, the relative success of crime scene samples and the geographical distribution of crimes. The DIP has broadened the dimensions of the information offered through the NZ DNA Databank and has furthered the understanding and investigative capability of both Police and forensic scientists. The outcomes of this research fit soundly with the current policies of 'intelligence led policing', which are being adopted by Police jurisdictions locally and overseas.

  5. Public participation in genetic databases: crossing the boundaries between biobanks and forensic DNA databases through the principle of solidarity

    PubMed Central

    Machado, Helena; Silva, Susana

    2015-01-01

    The ethical aspects of biobanks and forensic DNA databases are often treated as separate issues. As a reflection of this, public participation, or the involvement of citizens in genetic databases, has been approached differently in the fields of forensics and medicine. This paper aims to cross the boundaries between medicine and forensics by exploring the flows between the ethical issues presented in the two domains and the subsequent conceptualisation of public trust and legitimisation. We propose to introduce the concept of ‘solidarity’, traditionally applied only to medical and research biobanks, into a consideration of public engagement in medicine and forensics. Inclusion of a solidarity-based framework, in both medical biobanks and forensic DNA databases, raises new questions that should be included in the ethical debate, in relation to both health services/medical research and activities associated with the criminal justice system. PMID:26139851

  6. Mitochondrial DNA control region sequences from Nairobi (Kenya): inferring phylogenetic parameters for the establishment of a forensic database.

    PubMed

    Brandstätter, Anita; Peterson, Christine T; Irwin, Jodi A; Mpoke, Solomon; Koech, Davy K; Parson, Walther; Parsons, Thomas J

    2004-10-01

    Large forensic mtDNA databases which adhere to strict guidelines for generation and maintenance, are not available for many populations outside of the United States and western Europe. We have established a high quality mtDNA control region sequence database for urban Nairobi as both a reference database for forensic investigations, and as a tool to examine the genetic variation of Kenyan sequences in the context of known African variation. The Nairobi sequences exhibited high variation and a low random match probability, indicating utility for forensic testing. Haplogroup identification and frequencies were compared with those reported from other published studies on African, or African-origin populations from Mozambique, Sierra Leone, and the United States, and suggest significant differences in the mtDNA compositions of the various populations. The quality of the sequence data in our study was investigated and supported using phylogenetic measures. Our data demonstrate the diversity and distinctiveness of African populations, and underline the importance of establishing additional forensic mtDNA databases of indigenous African populations.

  7. DNA Commission of the International Society for Forensic Genetics: revised and extended guidelines for mitochondrial DNA typing.

    PubMed

    Parson, W; Gusmão, L; Hares, D R; Irwin, J A; Mayr, W R; Morling, N; Pokorak, E; Prinz, M; Salas, A; Schneider, P M; Parsons, T J

    2014-11-01

    The DNA Commission of the International Society of Forensic Genetics (ISFG) regularly publishes guidelines and recommendations concerning the application of DNA polymorphisms to the question of human identification. Previous recommendations published in 2000 addressed the analysis and interpretation of mitochondrial DNA (mtDNA) in forensic casework. While the foundations set forth in the earlier recommendations still apply, new approaches to the quality control, alignment and nomenclature of mitochondrial sequences, as well as the establishment of mtDNA reference population databases, have been developed. Here, we describe these developments and discuss their application to both mtDNA casework and mtDNA reference population databasing applications. While the generation of mtDNA for forensic casework has always been guided by specific standards, it is now well-established that data of the same quality are required for the mtDNA reference population data used to assess the statistical weight of the evidence. As a result, we introduce guidelines regarding sequence generation, as well as quality control measures based on the known worldwide mtDNA phylogeny, that can be applied to ensure the highest quality population data possible. For both casework and reference population databasing applications, the alignment and nomenclature of haplotypes is revised here and the phylogenetic alignment proffered as acceptable standard. In addition, the interpretation of heteroplasmy in the forensic context is updated, and the utility of alignment-free database searches for unbiased probability estimates is highlighted. Finally, we discuss statistical issues and define minimal standards for mtDNA database searches. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  8. Public participation in genetic databases: crossing the boundaries between biobanks and forensic DNA databases through the principle of solidarity.

    PubMed

    Machado, Helena; Silva, Susana

    2015-10-01

    The ethical aspects of biobanks and forensic DNA databases are often treated as separate issues. As a reflection of this, public participation, or the involvement of citizens in genetic databases, has been approached differently in the fields of forensics and medicine. This paper aims to cross the boundaries between medicine and forensics by exploring the flows between the ethical issues presented in the two domains and the subsequent conceptualisation of public trust and legitimisation. We propose to introduce the concept of 'solidarity', traditionally applied only to medical and research biobanks, into a consideration of public engagement in medicine and forensics. Inclusion of a solidarity-based framework, in both medical biobanks and forensic DNA databases, raises new questions that should be included in the ethical debate, in relation to both health services/medical research and activities associated with the criminal justice system. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  9. DNA typing in forensic medicine and in criminal investigations: a current survey.

    PubMed

    Benecke, M

    1997-05-01

    Since 1985 DNA typing of biological material has become one of the most powerful tools for personal identification in forensic medicine and in criminal investigations [1-6]. Classical DNA "fingerprinting" is increasingly being replaced by polymerase chain reaction (PCR) based technology which detects very short polymorphic stretches of DNA [7-15]. DNA loci which forensic scientists study do not code for proteins, and they are spread over the whole genome [16, 17]. These loci are neutral, and few provide any information about individuals except for their identity. Minute amounts of biological material are sufficient for DNA typing. Many European countries are beginning to establish databases to store DNA profiles of crime scenes and known offenders. A brief overview is given of past and present DNA typing and the establishment of forensic DNA databases in Europe.

  10. DNA typing in forensic medicine and in criminal investigations: a current survey

    NASA Astrophysics Data System (ADS)

    Benecke, Mark

    Since 1985 DNA typing of biological material has become one of the most powerful tools for personal identification in forensic medicine and in criminal investigations [1-6]. Classical DNA "fingerprinting" is increasingly being replaced by polymerase chain reaction (PCR) based technology which detects very short polymorphic stretches of DNA [7-15]. DNA loci which forensic scientists study do not code for proteins, and they are spread over the whole genome [16, 17]. These loci are neutral, and few provide any information about individuals except for their identity. Minute amounts of biological material are sufficient for DNA typing. Many European countries are beginning to establish databases to store DNA profiles of crime scenes and known offenders. A brief overview is given of past and present DNA typing and the establishment of forensic DNA databases in Europe.

  11. DNA fingerprinting in forensics: past, present, future

    PubMed Central

    2013-01-01

    DNA fingerprinting, one of the great discoveries of the late 20th century, has revolutionized forensic investigations. This review briefly recapitulates 30 years of progress in forensic DNA analysis which helps to convict criminals, exonerate the wrongly accused, and identify victims of crime, disasters, and war. Current standard methods based on short tandem repeats (STRs) as well as lineage markers (Y chromosome, mitochondrial DNA) are covered and applications are illustrated by casework examples. Benefits and risks of expanding forensic DNA databases are discussed and we ask what the future holds for forensic DNA fingerprinting. PMID:24245688

  12. Development and expansion of high-quality control region databases to improve forensic mtDNA evidence interpretation.

    PubMed

    Irwin, Jodi A; Saunier, Jessica L; Strouss, Katharine M; Sturk, Kimberly A; Diegoli, Toni M; Just, Rebecca S; Coble, Michael D; Parson, Walther; Parsons, Thomas J

    2007-06-01

    In an effort to increase the quantity, breadth and availability of mtDNA databases suitable for forensic comparisons, we have developed a high-throughput process to generate approximately 5000 control region sequences per year from regional US populations, global populations from which the current US population is derived and global populations currently under-represented in available forensic databases. The system utilizes robotic instrumentation for all laboratory steps from pre-extraction through sequence detection, and a rigorous eight-step, multi-laboratory data review process with entirely electronic data transfer. Over the past 3 years, nearly 10,000 control region sequences have been generated using this approach. These data are being made publicly available and should further address the need for consistent, high-quality mtDNA databases for forensic testing.

  13. Content based information retrieval in forensic image databases.

    PubMed

    Geradts, Zeno; Bijhold, Jurrien

    2002-03-01

    This paper gives an overview of the various available image databases and ways of searching these databases on image contents. The developments in research groups of searching in image databases is evaluated and compared with the forensic databases that exist. Forensic image databases of fingerprints, faces, shoeprints, handwriting, cartridge cases, drugs tablets, and tool marks are described. The developments in these fields appear to be valuable for forensic databases, especially that of the framework in MPEG-7, where the searching in image databases is standardized. In the future, the combination of the databases (also DNA-databases) and possibilities to combine these can result in stronger forensic evidence.

  14. Prisoners' expectations of the national forensic DNA database: surveillance and reconfiguration of individual rights.

    PubMed

    Machado, Helena; Santos, Filipe; Silva, Susana

    2011-07-15

    In this paper we aim to discuss how Portuguese prisoners know and what they feel about surveillance mechanisms related to the inclusion and deletion of the DNA profiles of convicted criminals in the national forensic database. Through a set of interviews with individuals currently imprisoned we focus on the ways this group perceives forensic DNA technologies. While the institutional and political discourses maintain that the restricted use and application of DNA profiles within the national forensic database protects individuals' rights, the prisoners claim that police misuse of such technologies potentially makes it difficult to escape from surveillance and acts as a mean of reinforcing the stigma of delinquency. The prisoners also argue that additional intensive and extensive use of surveillance devices might be more protective of their own individual rights and might possibly increase potential for exoneration. Crown Copyright © 2011. Published by Elsevier Ireland Ltd. All rights reserved.

  15. [Current status of DNA databases in the forensic field: new progress, new legal needs].

    PubMed

    Baeta, Miriam; Martínez-Jarreta, Begoña

    2009-01-01

    One of the most polemic issues regarding the use of deoxyribonucleic acid (DNA) in the legal sphere, refers to the creation of DNA databases. Until relatively recently, Spain did not have a law to support the establishment of a national DNA profile bank for forensic purposes, and preserve the fundamental rights of subjects whose data are archived therein. The regulatory law of police databases regarding identifiers obtained from DNA approved in 2007, covers this void in the Spanish legislation and responds to the incessant need to adapt the laws to continuous scientific and technological progress.

  16. Inclusiveness, Effectiveness and Intrusiveness: Issues in the Developing Uses of DNA Profiling in Support of Criminal Investigations

    PubMed Central

    2005-01-01

    Précis The rapid implementation and continuing expansion of forensic DNA databases around the world has been supported by claims about their effectiveness in criminal investigations and challenged by assertions of the resulting intrusiveness into individual privacy. These two competing perspectives provide the basis for ongoing considerations about the categories of persons who should be subject to nonconsensual DNA sampling and profile retention as well as the uses to which such profiles should be put. This paper uses the example of the current arrangements for forensic DNA databasing in England & Wales to discuss the ways in which the legislative and operational basis for police DNA databasing is reliant upon continuous deliberations over these and other matters by a range of key stakeholders. We also assess the effects of the recent innovative use of DNA databasing for ‘familial searching’ in this jurisdiction in order to show how agreed understandings about the appropriate uses of DNA can become unsettled and reformulated even where their investigative effectiveness is uncontested. We conclude by making some observations about the future of what is recognised to be the largest forensic DNA database in the world. PMID:16240734

  17. Evaluation of DNA mixtures from database search.

    PubMed

    Chung, Yuk-Ka; Hu, Yue-Qing; Fung, Wing K

    2010-03-01

    With the aim of bridging the gap between DNA mixture analysis and DNA database search, a novel approach is proposed to evaluate the forensic evidence of DNA mixtures when the suspect is identified by the search of a database of DNA profiles. General formulae are developed for the calculation of the likelihood ratio for a two-person mixture under general situations including multiple matches and imperfect evidence. The influence of the prior probabilities on the weight of evidence under the scenario of multiple matches is demonstrated by a numerical example based on Hong Kong data. Our approach is shown to be capable of presenting the forensic evidence of DNA mixtures in a comprehensive way when the suspect is identified through database search.

  18. Development of forensic-quality full mtGenome haplotypes: success rates with low template specimens.

    PubMed

    Just, Rebecca S; Scheible, Melissa K; Fast, Spence A; Sturk-Andreaggi, Kimberly; Higginbotham, Jennifer L; Lyons, Elizabeth A; Bush, Jocelyn M; Peck, Michelle A; Ring, Joseph D; Diegoli, Toni M; Röck, Alexander W; Huber, Gabriela E; Nagl, Simone; Strobl, Christina; Zimmermann, Bettina; Parson, Walther; Irwin, Jodi A

    2014-05-01

    Forensic mitochondrial DNA (mtDNA) testing requires appropriate, high quality reference population data for estimating the rarity of questioned haplotypes and, in turn, the strength of the mtDNA evidence. Available reference databases (SWGDAM, EMPOP) currently include information from the mtDNA control region; however, novel methods that quickly and easily recover mtDNA coding region data are becoming increasingly available. Though these assays promise to both facilitate the acquisition of mitochondrial genome (mtGenome) data and maximize the general utility of mtDNA testing in forensics, the appropriate reference data and database tools required for their routine application in forensic casework are lacking. To address this deficiency, we have undertaken an effort to: (1) increase the large-scale availability of high-quality entire mtGenome reference population data, and (2) improve the information technology infrastructure required to access/search mtGenome data and employ them in forensic casework. Here, we describe the application of a data generation and analysis workflow to the development of more than 400 complete, forensic-quality mtGenomes from low DNA quantity blood serum specimens as part of a U.S. National Institute of Justice funded reference population databasing initiative. We discuss the minor modifications made to a published mtGenome Sanger sequencing protocol to maintain a high rate of throughput while minimizing manual reprocessing with these low template samples. The successful use of this semi-automated strategy on forensic-like samples provides practical insight into the feasibility of producing complete mtGenome data in a routine casework environment, and demonstrates that large (>2kb) mtDNA fragments can regularly be recovered from high quality but very low DNA quantity specimens. Further, the detailed empirical data we provide on the amplification success rates across a range of DNA input quantities will be useful moving forward as PCR-based strategies for mtDNA enrichment are considered for targeted next-generation sequencing workflows. Copyright © 2014 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  19. DNA Barcodes for Forensically Important Fly Species in Brazil.

    PubMed

    Koroiva, Ricardo; de Souza, Mirian S; Roque, Fabio de Oliveira; Pepinelli, Mateus

    2018-04-07

    Here, we analyze 248 DNA barcode sequences of 35 fly species of forensic importance in Brazil. DNA barcoding can be effectively used for specimen identification of these species, allowing the unambiguous identification of 31 species, an overall success rate of 88%. Our results show a high rate of success for molecular identification using DNA barcoding sequences and open new perspectives for immature species identification, a subject on which limited forensic investigations exist in Tropical regions. We also address the implications of building a robust forensic DNA barcode database. A geographic bias is recognized for the COI dataset available for forensically important fly species in Brazil, with concentration of sequences from specimens collected mainly in sites located in the Cerrado, Mata Atlântica, and Pampa biomes.

  20. Forensic DNA Profiling and Database

    PubMed Central

    Panneerchelvam, S.; Norazmi, M.N.

    2003-01-01

    The incredible power of DNA technology as an identification tool had brought a tremendous change in crimnal justice . DNA data base is an information resource for the forensic DNA typing community with details on commonly used short tandem repeat (STR) DNA markers. This article discusses the essential steps in compilation of COmbined DNA Index System (CODIS) on validated polymerase chain amplified STRs and their use in crime detection. PMID:23386793

  1. The effect of wild card designations and rare alleles in forensic DNA database searches.

    PubMed

    Tvedebrink, Torben; Bright, Jo-Anne; Buckleton, John S; Curran, James M; Morling, Niels

    2015-05-01

    Forensic DNA databases are powerful tools used for the identification of persons of interest in criminal investigations. Typically, they consist of two parts: (1) a database containing DNA profiles of known individuals and (2) a database of DNA profiles associated with crime scenes. The risk of adventitious or chance matches between crimes and innocent people increases as the number of profiles within a database grows and more data is shared between various forensic DNA databases, e.g. from different jurisdictions. The DNA profiles obtained from crime scenes are often partial because crime samples may be compromised in quantity or quality. When an individual's profile cannot be resolved from a DNA mixture, ambiguity is introduced. A wild card, F, may be used in place of an allele that has dropped out or when an ambiguous profile is resolved from a DNA mixture. Variant alleles that do not correspond to any marker in the allelic ladder or appear above or below the extent of the allelic ladder range are assigned the allele designation R for rare allele. R alleles are position specific with respect to the observed/unambiguous allele. The F and R designations are made when the exact genotype has not been determined. The F and R designation are treated as wild cards for searching, which results in increased chance of adventitious matches. We investigated the probability of adventitious matches given these two types of wild cards. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  2. Mock jurors' use of error rates in DNA database trawls.

    PubMed

    Scurich, Nicholas; John, Richard S

    2013-12-01

    Forensic science is not infallible, as data collected by the Innocence Project have revealed. The rate at which errors occur in forensic DNA testing-the so-called "gold standard" of forensic science-is not currently known. This article presents a Bayesian analysis to demonstrate the profound impact that error rates have on the probative value of a DNA match. Empirical evidence on whether jurors are sensitive to this effect is equivocal: Studies have typically found they are not, while a recent, methodologically rigorous study found that they can be. This article presents the results of an experiment that examined this issue within the context of a database trawl case in which one DNA profile was tested against a multitude of profiles. The description of the database was manipulated (i.e., "medical" or "offender" database, or not specified) as was the rate of error (i.e., one-in-10 or one-in-1,000). Jury-eligible participants were nearly twice as likely to convict in the offender database condition compared to the condition not specified. The error rates did not affect verdicts. Both factors, however, affected the perception of the defendant's guilt, in the expected direction, although the size of the effect was meager compared to Bayesian prescriptions. The results suggest that the disclosure of an offender database to jurors might constitute prejudicial evidence, and calls for proficiency testing in forensic science as well as training of jurors are echoed. (c) 2013 APA, all rights reserved

  3. Characteristics of Populations of the Russian Federation over the Panel of Fifteen Loci Used for DNA Identification and in Forensic Medical Examination

    PubMed Central

    A Stepanov, V.; Balanovsky, O.P.; Melnikov, A.V.; Lash-Zavada, A.Yu.; Khar’kov, V.N.; Tyazhelova, T.V.; Akhmetova, V.L.; Zhukova, O.V.; Shneider, Yu.V.; Shil’nikova, I.N.; Borinskaya, S.A.; Marusin, A.V.; Spiridonova, M.G.; Simonova, K.V.; Khitrinskaya, I.Yu.; Radzhabov, M.O.; Romanov, A.G.; Shtygasheva, O.V.; Koshel’, S.M.; Balanovskaya, E.V.; Rybakova, A.V.; Khusnutdinova, E.K.; Puzyrev, V.P.; Yankovsky, N.K.

    2011-01-01

    Seventeen population groups within the Russian Federation were characterized for the first time using a panel of 15 genetic markers that are used for DNA identification and in forensic medical examinations. The degree of polymorphism and population diversity of microsatellite loci within the Power Plex system (Promega) in Russian populations; the distribution of alleles and genotypes within the populations of six cities and 11 ethnic groups of the Russian Federation; the levels of intra- and interpopulation genetic differentiation of population; genetic relations between populations; and the identification and forensic medical characteristics of the system of markers under study were determined. Significant differences were revealed between the Russian populations and the U.S. reference base that was used recently in the forensic medical examination of the RF. A database of the allelic frequencies of 15 microsatellite loci that are used for DNA identification and forensic medical examination was created; the database has the potential of becoming the reference for performing forensic medical examinations in Russia. The spatial organization of genetic diversity over the panel of the STR markers that are used for DNA identification was revealed. It represents the general regularities of geographical clusterization of human populations over various types of genetic markers. The necessity to take into account a population’s genetic structure during forensic medical examinations and DNA identification of criminal suspects was substantiated. PMID:22649684

  4. Forensic DNA methylation profiling from evidence material for investigative leads

    PubMed Central

    Lee, Hwan Young; Lee, Soong Deok; Shin, Kyoung-Jin

    2016-01-01

    DNA methylation is emerging as an attractive marker providing investigative leads to solve crimes in forensic genetics. The identification of body fluids that utilizes tissue-specific DNA methylation can contribute to solving crimes by predicting activity related to the evidence material. The age estimation based on DNA methylation is expected to reduce the number of potential suspects, when the DNA profile from the evidence does not match with any known person, including those stored in the forensic database. Moreover, the variation in DNA implicates environmental exposure, such as cigarette smoking and alcohol consumption, thereby suggesting the possibility to be used as a marker for predicting the lifestyle of potential suspect. In this review, we describe recent advances in our understanding of DNA methylation variations and the utility of DNA methylation as a forensic marker for advanced investigative leads from evidence materials. [BMB Reports 2016; 49(7): 359-369] PMID:27099236

  5. The future of forensic DNA analysis

    PubMed Central

    Butler, John M.

    2015-01-01

    The author's thoughts and opinions on where the field of forensic DNA testing is headed for the next decade are provided in the context of where the field has come over the past 30 years. Similar to the Olympic motto of ‘faster, higher, stronger’, forensic DNA protocols can be expected to become more rapid and sensitive and provide stronger investigative potential. New short tandem repeat (STR) loci have expanded the core set of genetic markers used for human identification in Europe and the USA. Rapid DNA testing is on the verge of enabling new applications. Next-generation sequencing has the potential to provide greater depth of coverage for information on STR alleles. Familial DNA searching has expanded capabilities of DNA databases in parts of the world where it is allowed. Challenges and opportunities that will impact the future of forensic DNA are explored including the need for education and training to improve interpretation of complex DNA profiles. PMID:26101278

  6. The mitochondrial DNA makeup of Romanians: A forensic mtDNA control region database and phylogenetic characterization.

    PubMed

    Turchi, Chiara; Stanciu, Florin; Paselli, Giorgia; Buscemi, Loredana; Parson, Walther; Tagliabracci, Adriano

    2016-09-01

    To evaluate the pattern of Romanian population from a mitochondrial perspective and to establish an appropriate mtDNA forensic database, we generated a high-quality mtDNA control region dataset from 407 Romanian subjects belonging to four major historical regions: Moldavia, Transylvania, Wallachia and Dobruja. The entire control region (CR) was analyzed by Sanger-type sequencing assays and the resulting 306 different haplotypes were classified into haplogroups according to the most updated mtDNA phylogeny. The Romanian gene pool is mainly composed of West Eurasian lineages H (31.7%), U (12.8%), J (10.8%), R (10.1%), T (9.1%), N (8.1%), HV (5.4%),K (3.7%), HV0 (4.2%), with exceptions of East Asian haplogroup M (3.4%) and African haplogroup L (0.7%). The pattern of mtDNA variation observed in this study indicates that the mitochondrial DNA pool is geographically homogeneous across Romania and that the haplogroup composition reveals signals of admixture of populations of different origin. The PCA scatterplot supported this scenario, with Romania located in southeastern Europe area, close to Bulgaria and Hungary, and as a borderland with respect to east Mediterranean and other eastern European countries. High haplotype diversity (0.993) and nucleotide diversity indices (0.00838±0.00426), together with low random match probability (0.0087) suggest the usefulness of this control region dataset as a forensic database in routine forensic mtDNA analysis and in the investigation of maternal genetic lineages in the Romanian population. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. My-Forensic-Loci-queries (MyFLq) framework for analysis of forensic STR data generated by massive parallel sequencing.

    PubMed

    Van Neste, Christophe; Vandewoestyne, Mado; Van Criekinge, Wim; Deforce, Dieter; Van Nieuwerburgh, Filip

    2014-03-01

    Forensic scientists are currently investigating how to transition from capillary electrophoresis (CE) to massive parallel sequencing (MPS) for analysis of forensic DNA profiles. MPS offers several advantages over CE such as virtually unlimited multiplexy of loci, combining both short tandem repeat (STR) and single nucleotide polymorphism (SNP) loci, small amplicons without constraints of size separation, more discrimination power, deep mixture resolution and sample multiplexing. We present our bioinformatic framework My-Forensic-Loci-queries (MyFLq) for analysis of MPS forensic data. For allele calling, the framework uses a MySQL reference allele database with automatically determined regions of interest (ROIs) by a generic maximal flanking algorithm which makes it possible to use any STR or SNP forensic locus. Python scripts were designed to automatically make allele calls starting from raw MPS data. We also present a method to assess the usefulness and overall performance of a forensic locus with respect to MPS, as well as methods to estimate whether an unknown allele, which sequence is not present in the MySQL database, is in fact a new allele or a sequencing error. The MyFLq framework was applied to an Illumina MiSeq dataset of a forensic Illumina amplicon library, generated from multilocus STR polymerase chain reaction (PCR) on both single contributor samples and multiple person DNA mixtures. Although the multilocus PCR was not yet optimized for MPS in terms of amplicon length or locus selection, the results show excellent results for most loci. The results show a high signal-to-noise ratio, correct allele calls, and a low limit of detection for minor DNA contributors in mixed DNA samples. Technically, forensic MPS affords great promise for routine implementation in forensic genomics. The method is also applicable to adjacent disciplines such as molecular autopsy in legal medicine and in mitochondrial DNA research. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

  8. FORENSIC DNA BANKING LEGISLATION IN DEVELOPING COUNTRIES: PRIVACY AND CONFIDENTIALITY CONCERNS REGARDING A DRAFT FROM TURKISH LEGISLATION.

    PubMed

    Ilgili, Önder; Arda, Berna

    This paper presents and analyses, in terms of privacy and confidentiality, the Turkish Draft Law on National DNA Database prepared in 2004, and concerning the use of DNA analysis for forensic objectives and identity verification in Turkey. After a short introduction including related concepts, we evaluate the draft law and provide articles about confidentiality. The evaluation reminded us of some important topics at international level for the developing countries. As a result, the need for sophisticated legislations about DNA databases, for solutions to issues related to the education of employees, and the technological dependency to other countries emerged as main challenges in terms of confidentiality for the developing countries. As seen in the Turkish Draft Law on National DNA Database, the protection of the fundamental rights and freedoms requires more care during the legislative efforts.

  9. The future of forensic DNA analysis.

    PubMed

    Butler, John M

    2015-08-05

    The author's thoughts and opinions on where the field of forensic DNA testing is headed for the next decade are provided in the context of where the field has come over the past 30 years. Similar to the Olympic motto of 'faster, higher, stronger', forensic DNA protocols can be expected to become more rapid and sensitive and provide stronger investigative potential. New short tandem repeat (STR) loci have expanded the core set of genetic markers used for human identification in Europe and the USA. Rapid DNA testing is on the verge of enabling new applications. Next-generation sequencing has the potential to provide greater depth of coverage for information on STR alleles. Familial DNA searching has expanded capabilities of DNA databases in parts of the world where it is allowed. Challenges and opportunities that will impact the future of forensic DNA are explored including the need for education and training to improve interpretation of complex DNA profiles. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  10. High-quality mtDNA control region sequences from 680 individuals sampled across the Netherlands to establish a national forensic mtDNA reference database.

    PubMed

    Chaitanya, Lakshmi; van Oven, Mannis; Brauer, Silke; Zimmermann, Bettina; Huber, Gabriela; Xavier, Catarina; Parson, Walther; de Knijff, Peter; Kayser, Manfred

    2016-03-01

    The use of mitochondrial DNA (mtDNA) for maternal lineage identification often marks the last resort when investigating forensic and missing-person cases involving highly degraded biological materials. As with all comparative DNA testing, a match between evidence and reference sample requires a statistical interpretation, for which high-quality mtDNA population frequency data are crucial. Here, we determined, under high quality standards, the complete mtDNA control-region sequences of 680 individuals from across the Netherlands sampled at 54 sites, covering the entire country with 10 geographic sub-regions. The complete mtDNA control region (nucleotide positions 16,024-16,569 and 1-576) was amplified with two PCR primers and sequenced with ten different sequencing primers using the EMPOP protocol. Haplotype diversity of the entire sample set was very high at 99.63% and, accordingly, the random-match probability was 0.37%. No population substructure within the Netherlands was detected with our dataset. Phylogenetic analyses were performed to determine mtDNA haplogroups. Inclusion of these high-quality data in the EMPOP database (accession number: EMP00666) will improve its overall data content and geographic coverage in the interest of all EMPOP users worldwide. Moreover, this dataset will serve as (the start of) a national reference database for mtDNA applications in forensic and missing person casework in the Netherlands. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  11. Forensic analysis of mtDNA haplotypes from two rural communities in Haiti reflects their population history.

    PubMed

    Wilson, Jamie L; Saint-Louis, Vertus; Auguste, Jensen O; Jackson, Bruce A

    2012-11-01

    Very little genetic data exist on Haitians, an estimated 1.2 million of whom, not including illegal immigrants, reside in the United States. The absence of genetic data on a population of this size reduces the discriminatory power of criminal and missing-person DNA databases in the United States and Caribbean. We present a forensic population study that provides the first genetic data set for Haiti. This study uses hypervariable segment one (HVS-1) mitochondrial DNA (mtDNA) nucleotide sequences from 291 subjects primarily from rural areas of northern and southern Haiti, where admixture would be minimal. Our results showed that the African maternal genetic component of Haitians had slightly higher West-Central African admixture than African-Americans and Dominicans, but considerably less than Afro-Brazilians. These results lay the foundation for further forensic genetics studies in the Haitian population and serve as a model for forensic mtDNA identification of individuals in other isolated or rural communities. © 2012 American Academy of Forensic Sciences.

  12. A Large Population Genetic Study of 15 Autosomal Short Tandem Repeat Loci for Establishment of Korean DNA Profile Database

    PubMed Central

    Yoo, Seong Yeon; Cho, Nam Soo; Park, Myung Jin; Seong, Ki Min; Hwang, Jung Ho; Song, Seok Bean; Han, Myun Soo; Lee, Won Tae; Chung, Ki Wha

    2011-01-01

    Genotyping of highly polymorphic short tandem repeat (STR) markers is widely used for the genetic identification of individuals in forensic DNA analyses and in paternity disputes. The National DNA Profile Databank recently established by the DNA Identification Act in Korea contains the computerized STR DNA profiles of individuals convicted of crimes. For the establishment of a large autosomal STR loci population database, 1805 samples were obtained at random from Korean individuals and 15 autosomal STR markers were analyzed using the AmpFlSTR Identifiler PCR Amplification kit. For the 15 autosomal STR markers, no deviations from the Hardy-Weinberg equilibrium were observed. The most informative locus in our data set was the D2S1338 with a discrimination power of 0.9699. The combined matching probability was 1.521 × 10-17. This large STR profile dataset including atypical alleles will be important for the establishment of the Korean DNA database and for forensic applications. PMID:21597912

  13. A large population genetic study of 15 autosomal short tandem repeat loci for establishment of Korean DNA profile database.

    PubMed

    Yoo, Seong Yeon; Cho, Nam Soo; Park, Myung Jin; Seong, Ki Min; Hwang, Jung Ho; Song, Seok Bean; Han, Myun Soo; Lee, Won Tae; Chung, Ki Wha

    2011-07-01

    Genotyping of highly polymorphic short tandem repeat (STR) markers is widely used for the genetic identification of individuals in forensic DNA analyses and in paternity disputes. The National DNA Profile Databank recently established by the DNA Identification Act in Korea contains the computerized STR DNA profiles of individuals convicted of crimes. For the establishment of a large autosomal STR loci population database, 1805 samples were obtained at random from Korean individuals and 15 autosomal STR markers were analyzed using the AmpFlSTR Identifiler PCR Amplification kit. For the 15 autosomal STR markers, no deviations from the Hardy-Weinberg equilibrium were observed. The most informative locus in our data set was the D2S1338 with a discrimination power of 0.9699. The combined matching probability was 1.521 × 10(-17). This large STR profile dataset including atypical alleles will be important for the establishment of the Korean DNA database and for forensic applications.

  14. STRBase: a short tandem repeat DNA database for the human identity testing community

    PubMed Central

    Ruitberg, Christian M.; Reeder, Dennis J.; Butler, John M.

    2001-01-01

    The National Institute of Standards and Technology (NIST) has compiled and maintained a Short Tandem Repeat DNA Internet Database (http://www.cstl.nist.gov/biotech/strbase/) since 1997 commonly referred to as STRBase. This database is an information resource for the forensic DNA typing community with details on commonly used short tandem repeat (STR) DNA markers. STRBase consolidates and organizes the abundant literature on this subject to facilitate on-going efforts in DNA typing. Observed alleles and annotated sequence for each STR locus are described along with a review of STR analysis technologies. Additionally, commercially available STR multiplex kits are described, published polymerase chain reaction (PCR) primer sequences are reported, and validation studies conducted by a number of forensic laboratories are listed. To supplement the technical information, addresses for scientists and hyperlinks to organizations working in this area are available, along with the comprehensive reference list of over 1300 publications on STRs used for DNA typing purposes. PMID:11125125

  15. The GHEP–EMPOP collaboration on mtDNA population data—A new resource for forensic casework

    PubMed Central

    Prieto, L.; Zimmermann, B.; Goios, A.; Rodriguez-Monge, A.; Paneto, G.G.; Alves, C.; Alonso, A.; Fridman, C.; Cardoso, S.; Lima, G.; Anjos, M.J.; Whittle, M.R.; Montesino, M.; Cicarelli, R.M.B.; Rocha, A.M.; Albarrán, C.; de Pancorbo, M.M.; Pinheiro, M.F.; Carvalho, M.; Sumita, D.R.; Parson, W.

    2011-01-01

    Mitochondrial DNA (mtDNA) population data for forensic purposes are still scarce for some populations, which may limit the evaluation of forensic evidence especially when the rarity of a haplotype needs to be determined in a database search. In order to improve the collection of mtDNA lineages from the Iberian and South American subcontinents, we here report the results of a collaborative study involving nine laboratories from the Spanish and Portuguese Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) and EMPOP. The individual laboratories contributed population data that were generated throughout the past 10 years, but in the majority of cases have not been made available to the scientific community. A total of 1019 haplotypes from Iberia (Basque Country, 2 general Spanish populations, 2 North and 1 Central Portugal populations), and Latin America (3 populations from São Paulo) were collected, reviewed and harmonized according to defined EMPOP criteria. The majority of data ambiguities that were found during the reviewing process (41 in total) were transcription errors confirming that the documentation process is still the most error-prone stage in reporting mtDNA population data, especially when performed manually. This GHEP–EMPOP collaboration has significantly improved the quality of the individual mtDNA datasets and adds mtDNA population data as valuable resource to the EMPOP database (www.empop.org). PMID:21075696

  16. Forgotten evidence: A mixed methods study of why sexual assault kits (SAKs) are not submitted for DNA forensic testing.

    PubMed

    Campbell, Rebecca; Fehler-Cabral, Giannina; Bybee, Deborah; Shaw, Jessica

    2017-10-01

    Throughout the United States, hundreds of thousands of sexual assault kits (SAKs) (also termed "rape kits") have not been submitted by the police for forensic DNA testing. DNA evidence can help sexual assault investigations and prosecutions by identifying offenders, revealing serial offenders through DNA matches across cases, and exonerating those who have been wrongly accused. In this article, we describe a 5-year action research project conducted with 1 city that had large numbers of untested SAKs-Detroit, Michigan-and our examination into why thousands of rape kits in this city were never submitted for forensic DNA testing. This mixed methods study combined ethnographic observations and qualitative interviews to identify stakeholders' perspectives as to why rape kits were not routinely submitted for testing. Then, we quantitatively examined whether these factors may have affected police practices regarding SAK testing, as evidenced by predictable changes in SAK submission rates over time. Chronic resource scarcity only partially explained why the organizations that serve rape victims-the police, crime lab, prosecution, and victim advocacy-could not test all rape kits, investigate all reported sexual assaults, and support all rape survivors. SAK submission rates significantly increased once criminal justice professionals in this city had full access to the FBI DNA forensic database Combined DNA Index System (CODIS), but even then, most SAKs were still not submitted for DNA testing. Building crime laboratories' capacities for DNA testing and training police on the utility of forensic evidence and best practices in sexual assault investigations can help remedy, and possibly prevent, the problem of untested rape kits. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  17. U.S. initiatives to strengthen forensic science & international standards in forensic DNA.

    PubMed

    Butler, John M

    2015-09-01

    A number of initiatives are underway in the United States in response to the 2009 critique of forensic science by a National Academy of Sciences committee. This article provides a broad review of activities including efforts of the White House National Science and Technology Council Subcommittee on Forensic Science and a partnership between the Department of Justice (DOJ) and the National Institute of Standards and Technology (NIST) to create the National Commission on Forensic Science and the Organization of Scientific Area Committees. These initiatives are seeking to improve policies and practices of forensic science. Efforts to fund research activities and aid technology transition and training in forensic science are also covered. The second portion of the article reviews standards in place or in development around the world for forensic DNA. Documentary standards are used to help define written procedures to perform testing. Physical standards serve as reference materials for calibration and traceability purposes when testing is performed. Both documentary and physical standards enable reliable data comparison, and standard data formats and common markers or testing regions are crucial for effective data sharing. Core DNA markers provide a common framework and currency for constructing DNA databases with compatible data. Recent developments in expanding core DNA markers in Europe and the United States are discussed. Published by Elsevier Ireland Ltd.

  18. U.S. initiatives to strengthen forensic science & international standards in forensic DNA

    PubMed Central

    Butler, John M.

    2015-01-01

    A number of initiatives are underway in the United States in response to the 2009 critique of forensic science by a National Academy of Sciences committee. This article provides a broad review of activities including efforts of the White House National Science and Technology Council Subcommittee on Forensic Science and a partnership between the Department of Justice (DOJ) and the National Institute of Standards and Technology (NIST) to create the National Commission on Forensic Science and the Organization of Scientific Area Committees. These initiatives are seeking to improve policies and practices of forensic science. Efforts to fund research activities and aid technology transition and training in forensic science are also covered. The second portion of the article reviews standards in place or in development around the world for forensic DNA. Documentary standards are used to help define written procedures to perform testing. Physical standards serve as reference materials for calibration and traceability purposes when testing is performed. Both documentary and physical standards enable reliable data comparison, and standard data formats and common markers or testing regions are crucial for effective data sharing. Core DNA markers provide a common framework and currency for constructing DNA databases with compatible data. Recent developments in expanding core DNA markers in Europe and the United States are discussed. PMID:26164236

  19. Integrating forensic information in a crime intelligence database.

    PubMed

    Rossy, Quentin; Ioset, Sylvain; Dessimoz, Damien; Ribaux, Olivier

    2013-07-10

    Since 2008, intelligence units of six states of the western part of Switzerland have been sharing a common database for the analysis of high volume crimes. On a daily basis, events reported to the police are analysed, filtered and classified to detect crime repetitions and interpret the crime environment. Several forensic outcomes are integrated in the system such as matches of traces with persons, and links between scenes detected by the comparison of forensic case data. Systematic procedures have been settled to integrate links assumed mainly through DNA profiles, shoemarks patterns and images. A statistical outlook on a retrospective dataset of series from 2009 to 2011 of the database informs for instance on the number of repetition detected or confirmed and increased by forensic case data. Time needed to obtain forensic intelligence in regard with the type of marks treated, is seen as a critical issue. Furthermore, the underlying integration process of forensic intelligence into the crime intelligence database raised several difficulties in regards of the acquisition of data and the models used in the forensic databases. Solutions found and adopted operational procedures are described and discussed. This process form the basis to many other researches aimed at developing forensic intelligence models. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  20. Attitudes regarding the national forensic DNA database: Survey data from the general public, prison inmates and prosecutors' offices in the Republic of Serbia.

    PubMed

    Teodorović, Smilja; Mijović, Dragan; Radovanović Nenadić, Una; Savić, Marina

    2017-05-01

    Worldwide, the establishment of national forensic DNA databases has transformed personal identification in the criminal justice system over the past two decades. It has also stimulated much debate centering on ethical issues, human rights, individual privacy, lack of safeguards and other standards. Therefore, a balance between effectiveness and intrusiveness of a national DNA repository is an imperative and needs to be achieved through a suitable legal framework. On its path to the European Union (EU), the Republic of Serbia is required to harmonize its national policies and legislation with the EU. Specifically, Chapter 24 of the EU acquis communautaire (Justice, Freedom and Security) stipulates the compulsory creation of a forensic DNA registry and adoption of corresponding legislation. This process is expected to occur in 2016. Thus, in light of launching the national DNA database, the goal of this work is to instigate a consultation with the Serbian public regarding their views on various aspects of the forensic DNA databank. Importantly, this study specifically assessed the opinions of distinct categories of citizens, including the general public, the prosecutors' offices staff, prisoners, prison guards, and students majoring in criminalistics. Our findings set a baseline for Serbian attitudes towards DNA databank custody, DNA sample and profile inclusion and retention criteria, ethical issues and concerns. Furthermore, results clearly demonstrate a permissive outlook of the respondents who are professional "beneficiaries" of genetic profiling and a restrictive position taken by the respondents whose genetic material has been acquired by the government. We believe that this opinion poll will be essential in discussions regarding a national DNA database, as well as in motivating further research on the reasons behind the observed views and subsequent development of educational strategies. All of these are, in turn, expected to aid the creation of suitable legislation and to increase societal confidence that the repository will be used in the legal system without interference with individual rights and freedoms. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. DNA in the Criminal Justice System: The DNA Success Story in Perspective.

    PubMed

    Mapes, Anna A; Kloosterman, Ate D; de Poot, Christianne J

    2015-07-01

    Current figures on the efficiency of DNA as an investigative tool in criminal investigations only tell part of the story. To get the DNA success story in the right perspective, we examined all forensic reports from serious (N = 116) and high-volume crime cases (N = 2791) over the year 2011 from one police region in the Netherlands. These data show that 38% of analyzed serious crime traces (N = 384) and 17% of analyzed high-volume crime traces (N = 386) did not result in a DNA profile. Turnaround times (from crime scene to DNA report) were 66 days for traces from serious crimes and 44 days for traces from high-volume crimes. Suspects were truly identified through a match with the Offender DNA database of the Netherlands in 3% of the serious crime cases and in 1% of the high-volume crime cases. These data are important for both the forensic laboratory and the professionals in the criminal justice system to further optimize forensic DNA testing as an investigative tool. © 2015 American Academy of Forensic Sciences.

  2. Forensics and mitochondrial DNA: applications, debates, and foundations.

    PubMed

    Budowle, Bruce; Allard, Marc W; Wilson, Mark R; Chakraborty, Ranajit

    2003-01-01

    Debate on the validity and reliability of scientific methods often arises in the courtroom. When the government (i.e., the prosecution) is the proponent of evidence, the defense is obliged to challenge its admissibility. Regardless, those who seek to use DNA typing methodologies to analyze forensic biological evidence have a responsibility to understand the technology and its applications so a proper foundation(s) for its use can be laid. Mitochondrial DNA (mtDNA), an extranuclear genome, has certain features that make it desirable for forensics, namely, high copy number, lack of recombination, and matrilineal inheritance. mtDNA typing has become routine in forensic biology and is used to analyze old bones, teeth, hair shafts, and other biological samples where nuclear DNA content is low. To evaluate results obtained by sequencing the two hypervariable regions of the control region of the human mtDNA genome, one must consider the genetically related issues of nomenclature, reference population databases, heteroplasmy, paternal leakage, recombination, and, of course, interpretation of results. We describe the approaches, the impact some issues may have on interpretation of mtDNA analyses, and some issues raised in the courtroom.

  3. Feline Non-repetitive Mitochondrial DNA Control Region Database for Forensic Evidence

    PubMed Central

    Grahn, R. A.; Kurushima, J. D.; Billings, N. C.; Grahn, J.C.; Halverson, J. L.; Hammer, E.; Ho, C.K.; Kun, T. J.; Levy, J.K.; Lipinski, M. J.; Mwenda, J.M.; Ozpinar, H.; Schuster, R.K; Shoorijeh, S.J.; Tarditi, C. R.; Waly, N.E.; Wictum, E. J.; Lyons, L. A.

    2010-01-01

    The domestic cat is the one of the most popular pets throughout the world. A by-product of owning, interacting with, or being in a household with a cat is the transfer of shed fur to clothing or personal objects. As trace evidence, transferred cat fur is a relatively untapped resource for forensic scientists. Both phenotypic and genotypic characteristics can be obtained from cat fur, but databases for neither aspect exist. Because cats incessantly groom, cat fur may have nucleated cells, not only in the hair bulb, but also as epithelial cells on the hair shaft deposited during the grooming process, thereby generally providing material for DNA profiling. To effectively exploit cat hair as a resource, representative databases must be established. This study evaluates 402 bp of the mtDNA control region (CR) from 1,394 cats, including cats from 25 distinct worldwide populations and 26 breeds. Eighty-three percent of the cats are represented by 12 major mitotypes. An additional 8.0% are clearly derived from the major mitotypes. Unique sequences were found in 7.5% of the cats. The overall genetic diversity for this data set was 0.8813 ± 0.0046 with a random match probability of 11.8%. This region of the cat mtDNA has discriminatory power suitable for forensic application worldwide. PMID:20457082

  4. Advances in DNA metabarcoding for food and wildlife forensic species identification.

    PubMed

    Staats, Martijn; Arulandhu, Alfred J; Gravendeel, Barbara; Holst-Jensen, Arne; Scholtens, Ingrid; Peelen, Tamara; Prins, Theo W; Kok, Esther

    2016-07-01

    Species identification using DNA barcodes has been widely adopted by forensic scientists as an effective molecular tool for tracking adulterations in food and for analysing samples from alleged wildlife crime incidents. DNA barcoding is an approach that involves sequencing of short DNA sequences from standardized regions and comparison to a reference database as a molecular diagnostic tool in species identification. In recent years, remarkable progress has been made towards developing DNA metabarcoding strategies, which involves next-generation sequencing of DNA barcodes for the simultaneous detection of multiple species in complex samples. Metabarcoding strategies can be used in processed materials containing highly degraded DNA e.g. for the identification of endangered and hazardous species in traditional medicine. This review aims to provide insight into advances of plant and animal DNA barcoding and highlights current practices and recent developments for DNA metabarcoding of food and wildlife forensic samples from a practical point of view. Special emphasis is placed on new developments for identifying species listed in the Convention on International Trade of Endangered Species (CITES) appendices for which reliable methods for species identification may signal and/or prevent illegal trade. Current technological developments and challenges of DNA metabarcoding for forensic scientists will be assessed in the light of stakeholders' needs.

  5. Young people's awareness on biobanking and DNA profiling: results of a questionnaire administered to Italian university students.

    PubMed

    Tozzo, Pamela; Fassina, Antonio; Caenazzo, Luciana

    2017-12-01

    Current policy approaches to social and ethical issues surrounding biobanks manifest lack of public information given by researchers and government, despite the evidence that Italian citizens are well informed about technical and other public perspectives of biotechnologies. For this reason, the focus of our survey was to interview our University's students on these aspects. The sample consisted of Padua University students (N = 959), who were administered a questionnaire comprising eight questions covering their knowledge about biobanks, their perception of the related benefits and risks, their willingness to donate samples to a biobank for research purposes, their attitude to having their own DNA profile included in a forensic DNA database, and the reasons behind their answers. The vast majority of the students invited to take part in the survey completed the questionnaire, and the number of participants sufficed to be considered representative of the target population. Despite the respondents' unfamiliarity with the topics explored, suggested by the huge group of respondents answering "I don't know" to the questions regarding Itaian regulation and reality, their answers demonstrate a general agreement to participate in a biobanking scheme for research purposes, as expressed by the 91% of respondents who were reportedly willing to donate their samples. As for the idea of a forensic DNA database, 35% of respondents said they would agree to having their profile included in such a database, even if they were not fully aware of the benefits and risks of such action.This study shows that Italian people with a higher education take a generally positive attitude to the idea of donating biological samples. It contributes to empirical evidence of what Italy's citizens understand about biobanking, and of their willingness to donate samples for research purposes, and also to have their genetic profiles included in a national forensic DNA database. Our findings may have clear implications for the policy discussion on biobanks in Italy, in particular it is important to take into account the Italian population's poor consciousness of forensic DNA database, in order to ensure a better interaction between policy makers and citizens and to make them more aware of the need to balance the individual's rights and the security of society.

  6. Population and forensic genetic analyses of mitochondrial DNA control region variation from six major provinces in the Korean population.

    PubMed

    Hong, Seung Beom; Kim, Ki Cheol; Kim, Wook

    2015-07-01

    We generated complete mitochondrial DNA (mtDNA) control region sequences from 704 unrelated individuals residing in six major provinces in Korea. In addition to our earlier survey of the distribution of mtDNA haplogroup variation, a total of 560 different haplotypes characterized by 271 polymorphic sites were identified, of which 473 haplotypes were unique. The gene diversity and random match probability were 0.9989 and 0.0025, respectively. According to the pairwise comparison of the 704 control region sequences, the mean number of pairwise differences between individuals was 13.47±6.06. Based on the result of mtDNA control region sequences, pairwise FST genetic distances revealed genetic homogeneity of the Korean provinces on a peninsular level, except in samples from Jeju Island. This result indicates there may be a need to formulate a local mtDNA database for Jeju Island, to avoid bias in forensic parameter estimates caused by genetic heterogeneity of the population. Thus, the present data may help not only in personal identification but also in determining maternal lineages to provide an expanded and reliable Korean mtDNA database. These data will be available on the EMPOP database via accession number EMP00661. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. An assessment of scientific and technical aspects of closed investigations of canine forensics DNA – case series from the University of California, Davis, USA

    PubMed Central

    Scharnhorst, Günther; Kanthaswamy, Sree

    2011-01-01

    Aim To describe and assess the scientific and technical aspects of animal forensic testing at the University of California, Davis. The findings and recommendations contained in this report are designed to assess the past, evaluate the present, and recommend reforms that will assist the animal forensic science community in providing the best possible services that comply with court standards and bear judicial scrutiny. Methods A batch of 32 closed files of domestic dog DNA cases processed at the University of California, Davis, between August 2003 and July 2005 were reviewed in this study. The case files comprised copies of all original paperwork, copies of the cover letter or final report, laboratory notes, notes on analyses, submission forms, internal chains of custody, printed images and photocopies of evidence, as well as the administrative and technical reviews of those cases. Results While the fundamental aspects of animal DNA testing may be reliable and acceptable, the scientific basis for forensic testing animal DNA needs to be improved substantially. In addition to a lack of standardized and validated genetic testing protocols, improvements are needed in a wide range of topics including quality assurance and quality control measures, sample handling, evidence testing, statistical analysis, and reporting. Conclusion This review implies that although a standardized panel of short tandem repeat and mitochondrial DNA markers and publicly accessible genetic databases for canine forensic DNA analysis are already available, the persistent lack of supporting resources, including standardized quality assurance and quality control programs, still plagues the animal forensic community. This report focuses on closed cases from the period 2003-2005, but extends its scope more widely to include other animal DNA forensic testing services. PMID:21674824

  8. An assessment of scientific and technical aspects of closed investigations of canine forensics DNA--case series from the University of California, Davis, USA.

    PubMed

    Scharnhorst, Günther; Kanthaswamy, Sree

    2011-06-01

    To describe and assess the scientific and technical aspects of animal forensic testing at the University of California, Davis. The findings and recommendations contained in this report are designed to assess the past, evaluate the present, and recommend reforms that will assist the animal forensic science community in providing the best possible services that comply with court standards and bear judicial scrutiny. A batch of 32 closed files of domestic dog DNA cases processed at the University of California, Davis, between August 2003 and July 2005 were reviewed in this study. The case files comprised copies of all original paperwork, copies of the cover letter or final report, laboratory notes, notes on analyses, submission forms, internal chains of custody, printed images and photocopies of evidence, as well as the administrative and technical reviews of those cases. While the fundamental aspects of animal DNA testing may be reliable and acceptable, the scientific basis for forensic testing animal DNA needs to be improved substantially. In addition to a lack of standardized and validated genetic testing protocols, improvements are needed in a wide range of topics including quality assurance and quality control measures, sample handling, evidence testing, statistical analysis, and reporting. This review implies that although a standardized panel of short tandem repeat and mitochondrial DNA markers and publicly accessible genetic databases for canine forensic DNA analysis are already available, the persistent lack of supporting resources, including standardized quality assurance and quality control programs, still plagues the animal forensic community. This report focuses on closed cases from the period 2003-2005, but extends its scope more widely to include other animal DNA forensic testing services.

  9. DNA Profiling of Convicted Offender Samples for the Combined DNA Index System

    ERIC Educational Resources Information Center

    Millard, Julie T

    2011-01-01

    The cornerstone of forensic chemistry is that a perpetrator inevitably leaves trace evidence at a crime scene. One important type of evidence is DNA, which has been instrumental in both the implication and exoneration of thousands of suspects in a wide range of crimes. The Combined DNA Index System (CODIS), a network of DNA databases, provides…

  10. Criminal genomic pragmatism: prisoners' representations of DNA technology and biosecurity.

    PubMed

    Machado, Helena; Silva, Susana

    2012-01-01

    Within the context of the use of DNA technology in crime investigation, biosecurity is perceived by different stakeholders according to their particular rationalities and interests. Very little is known about prisoners' perceptions and assessments of the uses of DNA technology in solving crime. To propose a conceptual model that serves to analyse and interpret prisoners' representations of DNA technology and biosecurity. A qualitative study using an interpretative approach based on 31 semi-structured tape-recorded interviews was carried out between May and September 2009, involving male inmates in three prisons located in the north of Portugal. The content analysis focused on the following topics: the meanings attributed to DNA and assessments of the risks and benefits of the uses of DNA technology and databasing in forensic applications. DNA was described as a record of identity, an exceptional material, and a powerful biometric identifier. The interviewees believed that DNA can be planted to incriminate suspects. Convicted offenders argued for the need to extend the criteria for the inclusion of DNA profiles in forensic databases and to restrict the removal of profiles. The conceptual model entitled criminal genomic pragmatism allows for an understanding of the views of prison inmates regarding DNA technology and biosecurity.

  11. Exploring the ancestry differentiation and inference capacity of the 28-plex AISNPs.

    PubMed

    Hao, Wei-Qi; Liu, Jing; Jiang, Li; Han, Jun-Ping; Wang, Ling; Li, Jiu-Ling; Ma, Quan; Liu, Chao; Wang, Hui-Jun; Li, Cai-Xia

    2018-06-07

    Inferring an unknown DNA's ancestry using a set of ancestry-informative single nucleotide polymorphisms (SNPs) in forensic science is useful to provide investigative leads. This is especially true when there is no DNA database match or specified suspect. Thus, a set of SNPs with highly robust and balanced differential power is strongly demanded in forensic science. In addition, it is also necessary to build a genotyping database for estimating the ancestry of an individual or an unknown DNA. For the differentiation of Africans, Europeans, East Asians, Native Americans, and Oceanians, the Global Nano set that includes just 31 SNPs was developed by de la Puente et al. Its ability for differentiation and balance was evaluated using the genotype data of the 1000 Genomes Phase III project and the Stanford University HGDP-CEPH. Just 402 samples were genotyped and analyzed as a reference set based on statistical methods. To validate the differentiating capacity using more samples, we developed a single-tube 28-plex SNP assay in which the SNPs were chosen from the 31 allelic loci of the Global AIMs Nano set. Three tri-allelic SNPs used to differentiate mixed-source DNA contribute little to population differentiation and were excluded here. Then, 998 individuals from 21 populations were typed, and these genotypes were combined with the genotype data obtained from 1000 Genomes Phase III and the Stanford University HGDP-CEPH (3090 total samples,43 populations) to estimate the power of this multiplex assay and build a database for the further inference of an individual or an unknown DNA sample in forensic practice.

  12. Characterizing the genetic structure of a forensic DNA database using a latent variable approach.

    PubMed

    Kruijver, Maarten

    2016-07-01

    Several problems in forensic genetics require a representative model of a forensic DNA database. Obtaining an accurate representation of the offender database can be difficult, since databases typically contain groups of persons with unregistered ethnic origins in unknown proportions. We propose to estimate the allele frequencies of the subpopulations comprising the offender database and their proportions from the database itself using a latent variable approach. We present a model for which parameters can be estimated using the expectation maximization (EM) algorithm. This approach does not rely on relatively small and possibly unrepresentative population surveys, but is driven by the actual genetic composition of the database only. We fit the model to a snapshot of the Dutch offender database (2014), which contains close to 180,000 profiles, and find that three subpopulations suffice to describe a large fraction of the heterogeneity in the database. We demonstrate the utility and reliability of the approach with three applications. First, we use the model to predict the number of false leads obtained in database searches. We assess how well the model predicts the number of false leads obtained in mock searches in the Dutch offender database, both for the case of familial searching for first degree relatives of a donor and searching for contributors to three-person mixtures. Second, we study the degree of partial matching between all pairs of profiles in the Dutch database and compare this to what is predicted using the latent variable approach. Third, we use the model to provide evidence to support that the Dutch practice of estimating match probabilities using the Balding-Nichols formula with a native Dutch reference database and θ=0.03 is conservative. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Geographic origin and individual assignment of Shorea platyclados (Dipterocarpaceae) for forensic identification

    PubMed Central

    Diway, Bibian; Khoo, Eyen

    2017-01-01

    The development of timber tracking methods based on genetic markers can provide scientific evidence to verify the origin of timber products and fulfill the growing requirement for sustainable forestry practices. In this study, the origin of an important Dark Red Meranti wood, Shorea platyclados, was studied by using the combination of seven chloroplast DNA and 15 short tandem repeats (STRs) markers. A total of 27 natural populations of S. platyclados were sampled throughout Malaysia to establish population level and individual level identification databases. A haplotype map was generated from chloroplast DNA sequencing for population identification, resulting in 29 multilocus haplotypes, based on 39 informative intraspecific variable sites. Subsequently, a DNA profiling database was developed from 15 STRs allowing for individual identification in Malaysia. Cluster analysis divided the 27 populations into two genetic clusters, corresponding to the region of Eastern and Western Malaysia. The conservativeness tests showed that the Malaysia database is conservative after removal of bias from population subdivision and sampling effects. Independent self-assignment tests correctly assigned individuals to the database in an overall 60.60−94.95% of cases for identified populations, and in 98.99−99.23% of cases for identified regions. Both the chloroplast DNA database and the STRs appear to be useful for tracking timber originating in Malaysia. Hence, this DNA-based method could serve as an effective addition tool to the existing forensic timber identification system for ensuring the sustainably management of this species into the future. PMID:28430826

  14. Automated forensic DNA purification optimized for FTA card punches and identifiler STR-based PCR analysis.

    PubMed

    Tack, Lois C; Thomas, Michelle; Reich, Karl

    2007-03-01

    Forensic labs globally face the same problem-a growing need to process a greater number and wider variety of samples for DNA analysis. The same forensic lab can be tasked all at once with processing mixed casework samples from crime scenes, convicted offender samples for database entry, and tissue from tsunami victims for identification. Besides flexibility in the robotic system chosen for forensic automation, there is a need, for each sample type, to develop new methodology that is not only faster but also more reliable than past procedures. FTA is a chemical treatment of paper, unique to Whatman Bioscience, and is used for the stabilization and storage of biological samples. Here, the authors describe optimization of the Whatman FTA Purification Kit protocol for use with the AmpFlSTR Identifiler PCR Amplification Kit.

  15. SAM: String-based sequence search algorithm for mitochondrial DNA database queries

    PubMed Central

    Röck, Alexander; Irwin, Jodi; Dür, Arne; Parsons, Thomas; Parson, Walther

    2011-01-01

    The analysis of the haploid mitochondrial (mt) genome has numerous applications in forensic and population genetics, as well as in disease studies. Although mtDNA haplotypes are usually determined by sequencing, they are rarely reported as a nucleotide string. Traditionally they are presented in a difference-coded position-based format relative to the corrected version of the first sequenced mtDNA. This convention requires recommendations for standardized sequence alignment that is known to vary between scientific disciplines, even between laboratories. As a consequence, database searches that are vital for the interpretation of mtDNA data can suffer from biased results when query and database haplotypes are annotated differently. In the forensic context that would usually lead to underestimation of the absolute and relative frequencies. To address this issue we introduce SAM, a string-based search algorithm that converts query and database sequences to position-free nucleotide strings and thus eliminates the possibility that identical sequences will be missed in a database query. The mere application of a BLAST algorithm would not be a sufficient remedy as it uses a heuristic approach and does not address properties specific to mtDNA, such as phylogenetically stable but also rapidly evolving insertion and deletion events. The software presented here provides additional flexibility to incorporate phylogenetic data, site-specific mutation rates, and other biologically relevant information that would refine the interpretation of mitochondrial DNA data. The manuscript is accompanied by freeware and example data sets that can be used to evaluate the new software (http://stringvalidation.org). PMID:21056022

  16. Validation of SmartRank: A likelihood ratio software for searching national DNA databases with complex DNA profiles.

    PubMed

    Benschop, Corina C G; van de Merwe, Linda; de Jong, Jeroen; Vanvooren, Vanessa; Kempenaers, Morgane; Kees van der Beek, C P; Barni, Filippo; Reyes, Eusebio López; Moulin, Léa; Pene, Laurent; Haned, Hinda; Sijen, Titia

    2017-07-01

    Searching a national DNA database with complex and incomplete profiles usually yields very large numbers of possible matches that can present many candidate suspects to be further investigated by the forensic scientist and/or police. Current practice in most forensic laboratories consists of ordering these 'hits' based on the number of matching alleles with the searched profile. Thus, candidate profiles that share the same number of matching alleles are not differentiated and due to the lack of other ranking criteria for the candidate list it may be difficult to discern a true match from the false positives or notice that all candidates are in fact false positives. SmartRank was developed to put forward only relevant candidates and rank them accordingly. The SmartRank software computes a likelihood ratio (LR) for the searched profile and each profile in the DNA database and ranks database entries above a defined LR threshold according to the calculated LR. In this study, we examined for mixed DNA profiles of variable complexity whether the true donors are retrieved, what the number of false positives above an LR threshold is and the ranking position of the true donors. Using 343 mixed DNA profiles over 750 SmartRank searches were performed. In addition, the performance of SmartRank and CODIS were compared regarding DNA database searches and SmartRank was found complementary to CODIS. We also describe the applicable domain of SmartRank and provide guidelines. The SmartRank software is open-source and freely available. Using the best practice guidelines, SmartRank enables obtaining investigative leads in criminal cases lacking a suspect. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. High-throughput STR analysis for DNA database using direct PCR.

    PubMed

    Sim, Jeong Eun; Park, Su Jeong; Lee, Han Chul; Kim, Se-Yong; Kim, Jong Yeol; Lee, Seung Hwan

    2013-07-01

    Since the Korean criminal DNA database was launched in 2010, we have focused on establishing an automated DNA database profiling system that analyzes short tandem repeat loci in a high-throughput and cost-effective manner. We established a DNA database profiling system without DNA purification using a direct PCR buffer system. The quality of direct PCR procedures was compared with that of conventional PCR system under their respective optimized conditions. The results revealed not only perfect concordance but also an excellent PCR success rate, good electropherogram quality, and an optimal intra/inter-loci peak height ratio. In particular, the proportion of DNA extraction required due to direct PCR failure could be minimized to <3%. In conclusion, the newly developed direct PCR system can be adopted for automated DNA database profiling systems to replace or supplement conventional PCR system in a time- and cost-saving manner. © 2013 American Academy of Forensic Sciences Published 2013. This article is a U.S. Government work and is in the public domain in the U.S.A.

  18. Genetics and attribution issues that confront the microbial forensics field.

    PubMed

    Budowle, Bruce

    2004-12-02

    The commission of an act of bioterrorism or biocrime is a real concern for law enforcement and society. Efforts are underway to develop a strong microbial forensic program to assist in identifying perpetrators of acts of bioterrorism and biocrimes, as well as serve as a deterrent for those who might commit such illicit acts. Genetic analyses of microbial organisms will likely be a powerful tool for attribution of criminal acts. There are some similarities to forensic human DNA analysis practices, such as: molecular biology technology, use of population databases, qualitative conclusions of test results, and the application of QA/QC practices. Differences include: database size and composition, statistical interpretation methods, and confidence/uncertainty in the outcome of an interpretation.

  19. Genetic identification of missing persons: DNA analysis of human remains and compromised samples.

    PubMed

    Alvarez-Cubero, M J; Saiz, M; Martinez-Gonzalez, L J; Alvarez, J C; Eisenberg, A J; Budowle, B; Lorente, J A

    2012-01-01

    Human identification has made great strides over the past 2 decades due to the advent of DNA typing. Forensic DNA typing provides genetic data from a variety of materials and individuals, and is applied to many important issues that confront society. Part of the success of DNA typing is the generation of DNA databases to help identify missing persons and to develop investigative leads to assist law enforcement. DNA databases house DNA profiles from convicted felons (and in some jurisdictions arrestees), forensic evidence, human remains, and direct and family reference samples of missing persons. These databases are essential tools, which are becoming quite large (for example the US Database contains 10 million profiles). The scientific, governmental and private communities continue to work together to standardize genetic markers for more effective worldwide data sharing, to develop and validate robust DNA typing kits that contain the reagents necessary to type core identity genetic markers, to develop technologies that facilitate a number of analytical processes and to develop policies to make human identity testing more effective. Indeed, DNA typing is integral to resolving a number of serious criminal and civil concerns, such as solving missing person cases and identifying victims of mass disasters and children who may have been victims of human trafficking, and provides information for historical studies. As more refined capabilities are still required, novel approaches are being sought, such as genetic testing by next-generation sequencing, mass spectrometry, chip arrays and pyrosequencing. Single nucleotide polymorphisms offer the potential to analyze severely compromised biological samples, to determine the facial phenotype of decomposed human remains and to predict the bioancestry of individuals, a new focus in analyzing this type of markers. Copyright © 2012 S. Karger AG, Basel.

  20. The National DNA Data Bank of Canada: a Quebecer perspective

    PubMed Central

    Milot, Emmanuel; Lecomte, Marie M. J.; Germain, Hugo; Crispino, Frank

    2013-01-01

    The Canadian National DNA Database was created in 1998 and first used in the mid-2000. Under management by the RCMP, the National DNA Data Bank of Canada offers each year satisfactory reported statistics for its use and efficiency. Built on two indexes (convicted offenders and crime scene indexes), the database not only provides increasing matches to offenders or linked traces to the various police forces of the nation, but offers a memory repository for cold cases. Despite these achievements, the data bank is now facing new challenges that will inevitably defy the way the database is currently used. These arise from the increasing power of detection of DNA traces, the diversity of demands from police investigators and the growth of the bank itself. Examples of new requirements from the database now include familial searches, low-copy-number analyses and the correct interpretation of mixed samples. This paper aims to develop on the original way set in Québec to address some of these challenges. Nevertheless, analytic and technological advances will inevitably lead to the introduction of new technologies in forensic laboratories, such as single cell sequencing, phenotyping, and proteomics. Furthermore, it will not only request a new holistic/global approach of the forensic molecular biology sciences (through academia and a more investigative role in the laboratory), but also new legal developments. Far from being exhaustive, this paper highlights some of the current use of the database, its potential for the future, and opportunity to expand as a result of recent technological developments in molecular biology, including, but not limited to DNA identification. PMID:24312124

  1. The National DNA Data Bank of Canada: a Quebecer perspective.

    PubMed

    Milot, Emmanuel; Lecomte, Marie M J; Germain, Hugo; Crispino, Frank

    2013-11-20

    The Canadian National DNA Database was created in 1998 and first used in the mid-2000. Under management by the RCMP, the National DNA Data Bank of Canada offers each year satisfactory reported statistics for its use and efficiency. Built on two indexes (convicted offenders and crime scene indexes), the database not only provides increasing matches to offenders or linked traces to the various police forces of the nation, but offers a memory repository for cold cases. Despite these achievements, the data bank is now facing new challenges that will inevitably defy the way the database is currently used. These arise from the increasing power of detection of DNA traces, the diversity of demands from police investigators and the growth of the bank itself. Examples of new requirements from the database now include familial searches, low-copy-number analyses and the correct interpretation of mixed samples. This paper aims to develop on the original way set in Québec to address some of these challenges. Nevertheless, analytic and technological advances will inevitably lead to the introduction of new technologies in forensic laboratories, such as single cell sequencing, phenotyping, and proteomics. Furthermore, it will not only request a new holistic/global approach of the forensic molecular biology sciences (through academia and a more investigative role in the laboratory), but also new legal developments. Far from being exhaustive, this paper highlights some of the current use of the database, its potential for the future, and opportunity to expand as a result of recent technological developments in molecular biology, including, but not limited to DNA identification.

  2. Age Estimation with DNA: From Forensic DNA Fingerprinting to Forensic (Epi)Genomics: A Mini-Review.

    PubMed

    Parson, Walther

    2018-01-01

    Forensic genetics developed from protein-based techniques a quarter of a century ago and became famous as "DNA fingerprinting," this being based on restriction fragment length polymorphisms (RFLPs) of high-molecular-weight DNA. The amplification of much smaller short tandem repeat (STR) sequences using the polymerase chain reaction soon replaced RFLP analysis and advanced to become the gold standard in genetic identification. Meanwhile, STR multiplexes have been developed and made commercially available which simultaneously amplify up to 30 STR loci from as little as 15 cells or fewer. The enormous information content that comes with the large variety of observed STR genotypes allows for genetic individualisation (with the exception of identical twins). Carefully selected core STR loci form the basis of intelligence-led DNA databases that provide investigative leads by linking unsolved crime scenes and criminals through their matched STR profiles. Nevertheless, the success of modern DNA fingerprinting depends on the availability of reference material from suspects. In order to provide new investigative leads in cases where such reference samples are absent, forensic scientists started to explore the prediction of phenotypic traits from the DNA of the evidentiary sample. This paradigm change now uses DNA and epigenetic markers to forecast characteristics that are useful to triage further investigative work. So far, the best investigated externally visible characteristics are eye, hair and skin colour, as well as geographic ancestry and age. Information on the chronological age of a stain donor (or any sample donor) is elemental for forensic investigations in a number of aspects and has, therefore, been explored by researchers in some detail. Among different methodological approaches tested to date, the methylation-sensitive analysis of carefully selected DNA markers (CpG sites) has brought the most promising results by providing prediction accuracies of ±3-4 years, which can be comparable to, or even surpass those from, eyewitness reports. This mini-review puts recent developments in age estimation via (epi)genetic methods in the context of the requirements and goals of forensic genetics and highlights paths to follow in the future of forensic genomics. © 2018 S. Karger AG, Basel.

  3. [Development of Chinese forensic Y-STR DNA database].

    PubMed

    Ge, Jian-Ye; Yan, Jiang-Wei; Xie, Qun; Sun, Hong-Yu; Zhou, Huai-Gu; Li, Bin

    2013-06-01

    Y chromosome is a male-specific paternal inherited chromosome. The STR markers on Y chromosome have been widely used in forensic practices. This article summarizes the characteristics of Y-STR and some factors are considered of selecting appropriate Y-STR markers for Chinese population. The prospects of existing and potential forensic applications of Y-STR profiles are discussed including familial excluding, familial searching, crowd source deducing, mixture sample testing, and kinship identifying. The research, development, verification of Y-STR kit, Y-STR mutation rate, and search software are explored and some suggestions are given.

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Velsko, S. P.

    The microbial DNA Index System (MiDIS) is a concept for a microbial forensic database and investigative decision support system that can be used to help investigators identify the sources of microbial agents that have been used in a criminal or terrorist incident. The heart of the proposed system is a rigorous method for calculating source probabilities by using certain fundamental sampling distributions associated with the propagation and mutation of microbes on disease transmission networks. This formalism has a close relationship to mitochondrial and Y-chromosomal human DNA forensics, and the proposed decision support system is somewhat analogous to the CODIS andmore » SWGDAM mtDNA databases. The MiDIS concept does not involve the use of opportunistic collections of microbial isolates and phylogenetic tree building as a basis for inference. A staged approach can be used to build MiDIS as an enduring capability, beginning with a pilot demonstration program that must meet user expectations for performance and validation before evolving into a continuing effort. Because MiDIS requires input from a a broad array of expertise including outbreak surveillance, field microbial isolate collection, microbial genome sequencing, disease transmission networks, and laboratory mutation rate studies, it will be necessary to assemble a national multi-laboratory team to develop such a system. The MiDIS effort would lend direction and focus to the national microbial genetics research program for microbial forensics, and would provide an appropriate forensic framework for interfacing to future national and international disease surveillance efforts.« less

  5. mtDNAmanager: a Web-based tool for the management and quality analysis of mitochondrial DNA control-region sequences

    PubMed Central

    Lee, Hwan Young; Song, Injee; Ha, Eunho; Cho, Sung-Bae; Yang, Woo Ick; Shin, Kyoung-Jin

    2008-01-01

    Background For the past few years, scientific controversy has surrounded the large number of errors in forensic and literature mitochondrial DNA (mtDNA) data. However, recent research has shown that using mtDNA phylogeny and referring to known mtDNA haplotypes can be useful for checking the quality of sequence data. Results We developed a Web-based bioinformatics resource "mtDNAmanager" that offers a convenient interface supporting the management and quality analysis of mtDNA sequence data. The mtDNAmanager performs computations on mtDNA control-region sequences to estimate the most-probable mtDNA haplogroups and retrieves similar sequences from a selected database. By the phased designation of the most-probable haplogroups (both expected and estimated haplogroups), mtDNAmanager enables users to systematically detect errors whilst allowing for confirmation of the presence of clear key diagnostic mutations and accompanying mutations. The query tools of mtDNAmanager also facilitate database screening with two options of "match" and "include the queried nucleotide polymorphism". In addition, mtDNAmanager provides Web interfaces for users to manage and analyse their own data in batch mode. Conclusion The mtDNAmanager will provide systematic routines for mtDNA sequence data management and analysis via easily accessible Web interfaces, and thus should be very useful for population, medical and forensic studies that employ mtDNA analysis. mtDNAmanager can be accessed at . PMID:19014619

  6. Developmental validation of the HIrisPlex system: DNA-based eye and hair colour prediction for forensic and anthropological usage.

    PubMed

    Walsh, Susan; Chaitanya, Lakshmi; Clarisse, Lindy; Wirken, Laura; Draus-Barini, Jolanta; Kovatsi, Leda; Maeda, Hitoshi; Ishikawa, Takaki; Sijen, Titia; de Knijff, Peter; Branicki, Wojciech; Liu, Fan; Kayser, Manfred

    2014-03-01

    Forensic DNA Phenotyping or 'DNA intelligence' tools are expected to aid police investigations and find unknown individuals by providing information on externally visible characteristics of unknown suspects, perpetrators and missing persons from biological samples. This is especially useful in cases where conventional DNA profiling or other means remain non-informative. Recently, we introduced the HIrisPlex system, capable of predicting both eye and hair colour from DNA. In the present developmental validation study, we demonstrate that the HIrisPlex assay performs in full agreement with the Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines providing an essential prerequisite for future HIrisPlex applications to forensic casework. The HIrisPlex assay produces complete profiles down to only 63 pg of DNA. Species testing revealed human specificity for a complete HIrisPlex profile, while only non-human primates showed the closest full profile at 20 out of the 24 DNA markers, in all animals tested. Rigorous testing of simulated forensic casework samples such as blood, semen, saliva stains, hairs with roots as well as extremely low quantity touch (trace) DNA samples, produced complete profiles in 88% of cases. Concordance testing performed between five independent forensic laboratories displayed consistent reproducible results on varying types of DNA samples. Due to its design, the assay caters for degraded samples, underlined here by results from artificially degraded DNA and from simulated casework samples of degraded DNA. This aspect was also demonstrated previously on DNA samples from human remains up to several hundreds of years old. With this paper, we also introduce enhanced eye and hair colour prediction models based on enlarged underlying databases of HIrisPlex genotypes and eye/hair colour phenotypes (eye colour: N = 9188 and hair colour: N = 1601). Furthermore, we present an online web-based system for individual eye and hair colour prediction from full and partial HIrisPlex DNA profiles. By demonstrating that the HIrisPlex assay is fully compatible with the SWGDAM guidelines, we provide the first forensically validated DNA test system for parallel eye and hair colour prediction now available to forensic laboratories for immediate casework application, including missing person cases. Given the robustness and sensitivity described here and in previous work, the HIrisPlex system is also suitable for analysing old and ancient DNA in anthropological and evolutionary studies. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  7. A high-throughput Sanger strategy for human mitochondrial genome sequencing

    PubMed Central

    2013-01-01

    Background A population reference database of complete human mitochondrial genome (mtGenome) sequences is needed to enable the use of mitochondrial DNA (mtDNA) coding region data in forensic casework applications. However, the development of entire mtGenome haplotypes to forensic data quality standards is difficult and laborious. A Sanger-based amplification and sequencing strategy that is designed for automated processing, yet routinely produces high quality sequences, is needed to facilitate high-volume production of these mtGenome data sets. Results We developed a robust 8-amplicon Sanger sequencing strategy that regularly produces complete, forensic-quality mtGenome haplotypes in the first pass of data generation. The protocol works equally well on samples representing diverse mtDNA haplogroups and DNA input quantities ranging from 50 pg to 1 ng, and can be applied to specimens of varying DNA quality. The complete workflow was specifically designed for implementation on robotic instrumentation, which increases throughput and reduces both the opportunities for error inherent to manual processing and the cost of generating full mtGenome sequences. Conclusions The described strategy will assist efforts to generate complete mtGenome haplotypes which meet the highest data quality expectations for forensic genetic and other applications. Additionally, high-quality data produced using this protocol can be used to assess mtDNA data developed using newer technologies and chemistries. Further, the amplification strategy can be used to enrich for mtDNA as a first step in sample preparation for targeted next-generation sequencing. PMID:24341507

  8. DNA-barcoding of forensically important blow flies (Diptera: Calliphoridae) in the Caribbean Region

    PubMed Central

    Agnarsson, Ingi

    2017-01-01

    Correct identification of forensically important insects, such as flies in the family Calliphoridae, is a crucial step for them to be used as evidence in legal investigations. Traditional identification based on morphology has been effective, but has some limitations when it comes to identifying immature stages of certain species. DNA-barcoding, using COI, has demonstrated potential for rapid and accurate identification of Calliphoridae, however, this gene does not reliably distinguish among some recently diverged species, raising questions about its use for delimitation of species of forensic importance. To facilitate DNA based identification of Calliphoridae in the Caribbean we developed a vouchered reference collection from across the region, and a DNA sequence database, and further added the nuclear ITS2 as a second marker to increase accuracy of identification through barcoding. We morphologically identified freshly collected specimens, did phylogenetic analyses and employed several species delimitation methods for a total of 468 individuals representing 19 described species. Our results show that combination of COI + ITS2 genes yields more accurate identification and diagnoses, and better agreement with morphological data, than the mitochondrial barcodes alone. All of our results from independent and concatenated trees and most of the species delimitation methods yield considerably higher diversity estimates than the distance based approach and morphology. Molecular data support at least 24 distinct clades within Calliphoridae in this study, recovering substantial geographic variation for Lucilia eximia, Lucilia retroversa, Lucilia rica and Chloroprocta idioidea, probably indicating several cryptic species. In sum, our study demonstrates the importance of employing a second nuclear marker for barcoding analyses and species delimitation of calliphorids, and the power of molecular data in combination with a complete reference database to enable identification of taxonomically and geographically diverse insects of forensic importance. PMID:28761780

  9. Filipino DNA variation at 12 X-chromosome short tandem repeat markers.

    PubMed

    Salvador, Jazelyn M; Apaga, Dame Loveliness T; Delfin, Frederick C; Calacal, Gayvelline C; Dennis, Sheila Estacio; De Ungria, Maria Corazon A

    2018-06-08

    Demands for solving complex kinship scenarios where only distant relatives are available for testing have risen in the past years. In these instances, other genetic markers such as X-chromosome short tandem repeat (X-STR) markers are employed to supplement autosomal and Y-chromosomal STR DNA typing. However, prior to use, the degree of STR polymorphism in the population requires evaluation through generation of an allele or haplotype frequency population database. This population database is also used for statistical evaluation of DNA typing results. Here, we report X-STR data from 143 unrelated Filipino male individuals who were genotyped via conventional polymerase chain reaction-capillary electrophoresis (PCR-CE) using the 12 X-STR loci included in the Investigator ® Argus X-12 kit (Qiagen) and via massively parallel sequencing (MPS) of seven X-STR loci included in the ForenSeq ™ DNA Signature Prep kit of the MiSeq ® FGx ™ Forensic Genomics System (Illumina). Allele calls between PCR-CE and MPS systems were consistent (100% concordance) across seven overlapping X-STRs. Allele and haplotype frequencies and other parameters of forensic interest were calculated based on length (PCR-CE, 12 X-STRs) and sequence (MPS, seven X-STRs) variations observed in the population. Results of our study indicate that the 12 X-STRs in the PCR-CE system are highly informative for the Filipino population. MPS of seven X-STR loci identified 73 X-STR alleles compared with 55 X-STR alleles that were identified solely by length via PCR-CE. Of the 73 sequence-based alleles observed, six alleles have not been reported in the literature. The population data presented here may serve as a reference Philippine frequency database of X-STRs for forensic casework applications. Copyright © 2018 Elsevier B.V. All rights reserved.

  10. [Review of Second Generation Sequencing and Its Application in Forensic Genetics].

    PubMed

    Zhang, S H; Bian, Y N; Zhao, Q; Li, C T

    2016-08-01

    The rapid development of second generation sequencing (SGS) within the past few years has led to the increasement of data throughput and read length while at the same time brought down substantially the sequencing cost. This made new breakthrough in the area of biology and ushered the forensic genetics into a new era. Based on the history of sequencing application in forensic genetics, this paper reviews the importance of sequencing technologies for genetic marker detection. The application status and potential of SGS in forensic genetics are discussed based on the already explored SGS platforms of Roche, Illumina and Life Technologies. With these platforms, DNA markers (SNP, STR), RNA markers (mRNA, microRNA) and whole mtDNA can be sequenced. However, development and validation of application kits, maturation of analysis software, connection to the existing databases and the possible ethical issues occurred with big data will be the key factors that determine whether this technology can substitute or supplement PCR-CE, the mature technology, and be widely used for cases detection. Copyright© by the Editorial Department of Journal of Forensic Medicine.

  11. Current genetic methodologies in the identification of disaster victims and in forensic analysis.

    PubMed

    Ziętkiewicz, Ewa; Witt, Magdalena; Daca, Patrycja; Zebracka-Gala, Jadwiga; Goniewicz, Mariusz; Jarząb, Barbara; Witt, Michał

    2012-02-01

    This review presents the basic problems and currently available molecular techniques used for genetic profiling in disaster victim identification (DVI). The environmental conditions of a mass disaster often result in severe fragmentation, decomposition and intermixing of the remains of victims. In such cases, traditional identification based on the anthropological and physical characteristics of the victims is frequently inconclusive. This is the reason why DNA profiling became the gold standard for victim identification in mass-casualty incidents (MCIs) or any forensic cases where human remains are highly fragmented and/or degraded beyond recognition. The review provides general information about the sources of genetic material for DNA profiling, the genetic markers routinely used during genetic profiling (STR markers, mtDNA and single-nucleotide polymorphisms [SNP]) and the basic statistical approaches used in DNA-based disaster victim identification. Automated technological platforms that allow the simultaneous analysis of a multitude of genetic markers used in genetic identification (oligonucleotide microarray techniques and next-generation sequencing) are also presented. Forensic and population databases containing information on human variability, routinely used for statistical analyses, are discussed. The final part of this review is focused on recent developments, which offer particularly promising tools for forensic applications (mRNA analysis, transcriptome variation in individuals/populations and genetic profiling of specific cells separated from mixtures).

  12. Developmental validation of the MiSeq FGx Forensic Genomics System for Targeted Next Generation Sequencing in Forensic DNA Casework and Database Laboratories.

    PubMed

    Jäger, Anne C; Alvarez, Michelle L; Davis, Carey P; Guzmán, Ernesto; Han, Yonmee; Way, Lisa; Walichiewicz, Paulina; Silva, David; Pham, Nguyen; Caves, Glorianna; Bruand, Jocelyne; Schlesinger, Felix; Pond, Stephanie J K; Varlaro, Joe; Stephens, Kathryn M; Holt, Cydne L

    2017-05-01

    Human DNA profiling using PCR at polymorphic short tandem repeat (STR) loci followed by capillary electrophoresis (CE) size separation and length-based allele typing has been the standard in the forensic community for over 20 years. Over the last decade, Next-Generation Sequencing (NGS) matured rapidly, bringing modern advantages to forensic DNA analysis. The MiSeq FGx™ Forensic Genomics System, comprised of the ForenSeq™ DNA Signature Prep Kit, MiSeq FGx™ Reagent Kit, MiSeq FGx™ instrument and ForenSeq™ Universal Analysis Software, uses PCR to simultaneously amplify up to 231 forensic loci in a single multiplex reaction. Targeted loci include Amelogenin, 27 common, forensic autosomal STRs, 24 Y-STRs, 7 X-STRs and three classes of single nucleotide polymorphisms (SNPs). The ForenSeq™ kit includes two primer sets: Amelogenin, 58 STRs and 94 identity informative SNPs (iiSNPs) are amplified using DNA Primer Set A (DPMA; 153 loci); if a laboratory chooses to generate investigative leads using DNA Primer Set B, amplification is targeted to the 153 loci in DPMA plus 22 phenotypic informative (piSNPs) and 56 biogeographical ancestry SNPs (aiSNPs). High-resolution genotypes, including detection of intra-STR sequence variants, are semi-automatically generated with the ForenSeq™ software. This system was subjected to developmental validation studies according to the 2012 Revised SWGDAM Validation Guidelines. A two-step PCR first amplifies the target forensic STR and SNP loci (PCR1); unique, sample-specific indexed adapters or "barcodes" are attached in PCR2. Approximately 1736 ForenSeq™ reactions were analyzed. Studies include DNA substrate testing (cotton swabs, FTA cards, filter paper), species studies from a range of nonhuman organisms, DNA input sensitivity studies from 1ng down to 7.8pg, two-person human DNA mixture testing with three genotype combinations, stability analysis of partially degraded DNA, and effects of five commonly encountered PCR inhibitors. Calculations from ForenSeq™ STR and SNP repeatability and reproducibility studies (1ng template) indicate 100.0% accuracy of the MiSeq FGx™ System in allele calling relative to CE for STRs (1260 samples), and >99.1% accuracy relative to bead array typing for SNPs (1260 samples for iiSNPs, 310 samples for aiSNPs and piSNPs), with >99.0% and >97.8% precision, respectively. Call rates of >99.0% were observed for all STRs and SNPs amplified with both ForenSeq™ primer mixes. Limitations of the MiSeq FGx™ System are discussed. Results described here demonstrate that the MiSeq FGx™ System meets forensic DNA quality assurance guidelines with robust, reliable, and reproducible performance on samples of various quantities and qualities. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  13. Application of Next-generation Sequencing Technology in Forensic Science

    PubMed Central

    Yang, Yaran; Xie, Bingbing; Yan, Jiangwei

    2014-01-01

    Next-generation sequencing (NGS) technology, with its high-throughput capacity and low cost, has developed rapidly in recent years and become an important analytical tool for many genomics researchers. New opportunities in the research domain of the forensic studies emerge by harnessing the power of NGS technology, which can be applied to simultaneously analyzing multiple loci of forensic interest in different genetic contexts, such as autosomes, mitochondrial and sex chromosomes. Furthermore, NGS technology can also have potential applications in many other aspects of research. These include DNA database construction, ancestry and phenotypic inference, monozygotic twin studies, body fluid and species identification, and forensic animal, plant and microbiological analyses. Here we review the application of NGS technology in the field of forensic science with the aim of providing a reference for future forensics studies and practice. PMID:25462152

  14. Database extraction strategies for low-template evidence.

    PubMed

    Bleka, Øyvind; Dørum, Guro; Haned, Hinda; Gill, Peter

    2014-03-01

    Often in forensic cases, the profile of at least one of the contributors to a DNA evidence sample is unknown and a database search is needed to discover possible perpetrators. In this article we consider two types of search strategies to extract suspects from a database using methods based on probability arguments. The performance of the proposed match scores is demonstrated by carrying out a study of each match score relative to the level of allele drop-out in the crime sample, simulating low-template DNA. The efficiency was measured by random man simulation and we compared the performance using the SGM Plus kit and the ESX 17 kit for the Norwegian population, demonstrating that the latter has greatly enhanced power to discover perpetrators of crime in large national DNA databases. The code for the database extraction strategies will be prepared for release in the R-package forensim. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  15. Leading-edge forensic DNA analyses and the necessity of including crime scene investigators, police officers and technicians in a DNA elimination database.

    PubMed

    Lapointe, Martine; Rogic, Anita; Bourgoin, Sarah; Jolicoeur, Christine; Séguin, Diane

    2015-11-01

    In recent years, sophisticated technology has significantly increased the sensitivity and analytical power of genetic analyses so that very little starting material may now produce viable genetic profiles. This sensitivity however, has also increased the risk of detecting unknown genetic profiles assumed to be that of the perpetrator, yet originate from extraneous sources such as from crime scene workers. These contaminants may mislead investigations, keeping criminal cases active and unresolved for long spans of time. Voluntary submission of DNA samples from crime scene workers is fairly low, therefore we have created a promotional method for our staff elimination database that has resulted in a significant increase in voluntary samples since 2011. Our database enforces privacy safeguards and allows for optional anonymity to all staff members. We also offer information sessions at various police precincts to advise crime scene workers of the importance and success of our staff elimination database. This study, a pioneer in its field, has obtained 327 voluntary submissions from crime scene workers to date, of which 46 individual profiles (14%) have been matched to 58 criminal cases. By implementing our methods and respect for individual privacy, forensic laboratories everywhere may see similar growth and success in explaining unidentified genetic profiles in stagnate criminal cases. Crown Copyright © 2015. Published by Elsevier Ireland Ltd. All rights reserved.

  16. Interpretation guidelines of a standard Y-chromosome STR 17-plex PCR-CE assay for crime casework.

    PubMed

    Roewer, Lutz; Geppert, Maria

    2012-01-01

    Y-STR analysis is an invaluable tool to examine evidence in sexual assault cases and in other forensic casework. Unambiguous detection of the male component in DNA mixtures with a high female background is still the main field of application of forensic Y-STR haplotyping. In the last years, powerful technologies including a 17-locus multiplex PCR assay have been introduced in the forensic laboratories. At the same time, statistical methods have been developed and adapted for interpretation of a nonrecombining, linear marker as the Y-chromosome which shows a strongly clustered geographical distribution due to the linear inheritance and the patrilocality of ancestral groups. Large population databases, namely the Y-STR Haplotype Reference Database (YHRD), have been established to assess the evidentiary value of Y-STR matches by means of frequency estimation methods (counting and extrapolation).

  17. Forensic botany: species identification of botanical trace evidence using a multigene barcoding approach.

    PubMed

    Ferri, Gianmarco; Alù, Milena; Corradini, Beatrice; Beduschi, Giovanni

    2009-09-01

    Forensic botany can provide significant supporting evidence during criminal investigations. However, it is still an underutilized field of investigation with its most common application limited to identifying specific as well as suspected illegal plants. The ubiquitous presence of plant species can be useful in forensics, but the absence of an accurate identification system remains the major obstacle to the present inability to routinely and correctly identify trace botanical evidence. Many plant materials cannot be identified and differentiated to the species level by traditional morphological characteristics when botanical specimens are degraded and lack physical features. By taking advantage of a universal barcode system, DNA sequencing, and other biomolecular techniques used routinely in forensic investigations, two chloroplast DNA regions were evaluated for their use as "barcoding" markers for plant identification in the field of forensics. We therefore investigated the forensic use of two non-coding plastid regions, psbA-trnH and trnL-trnF, to create a multimarker system for species identification that could be useful throughout the plant kingdom. The sequences from 63 plants belonging to our local flora were submitted and registered on the GenBank database. Sequence comparison to set up the level of identification (species, genus, or family) through Blast algorithms allowed us to assess the suitability of this method. The results confirmed the effectiveness of our botanic universal multimarker assay in forensic investigations.

  18. Familial searching: a specialist forensic DNA profiling service utilising the National DNA Database to identify unknown offenders via their relatives--the UK experience.

    PubMed

    Maguire, C N; McCallum, L A; Storey, C; Whitaker, J P

    2014-01-01

    The National DNA Database (NDNAD) of England and Wales was established on April 10th 1995. The NDNAD is governed by a variety of legislative instruments that mean that DNA samples can be taken if an individual is arrested and detained in a police station. The biological samples and the DNA profiles derived from them can be used for purposes related to the prevention and detection of crime, the investigation of an offence and for the conduct of a prosecution. Following the South East Asian Tsunami of December 2004, the legislation was amended to allow the use of the NDNAD to assist in the identification of a deceased person or of a body part where death has occurred from natural causes or from a natural disaster. The UK NDNAD now contains the DNA profiles of approximately 6 million individuals representing 9.6% of the UK population. As the science of DNA profiling advanced, the National DNA Database provided a potential resource for increased intelligence beyond the direct matching for which it was originally created. The familial searching service offered to the police by several UK forensic science providers exploits the size and geographic coverage of the NDNAD and the fact that close relatives of an offender may share a significant proportion of that offender's DNA profile and will often reside in close geographic proximity to him or her. Between 2002 and 2011 Forensic Science Service Ltd. (FSS) provided familial search services to support 188 police investigations, 70 of which are still active cases. This technique, which may be used in serious crime cases or in 'cold case' reviews when there are few or no investigative leads, has led to the identification of 41 perpetrators or suspects. In this paper we discuss the processes, utility, and governance of the familial search service in which the NDNAD is searched for close genetic relatives of an offender who has left DNA evidence at a crime scene, but whose DNA profile is not represented within the NDNAD. We discuss the scientific basis of the familial search approach, other DNA-based methods for eliminating individuals from the candidate lists generated by these NDNAD searches, the value of filtering these lists by age, ethnic appearance and geography and the governance required by the NDNAD Strategy Board when a police force commissions a familial search. We present the FSS data in relation to the utility of the familial searching service and demonstrate the power of the technique by reference to casework examples. We comment on the uptake of familial searching of DNA databases in the USA, the Netherlands, Australia, and New Zealand. Finally, following the adverse ruling by the European Court of Human Rights against the UK in regard to the S & Marper cases and the consequent introduction of the Protection of Freedoms Act (2012), we discuss the impact that changes to regulations concerning the storage of DNA samples will have on the continuing provision of familial searching of the National DNA Database in England and Wales. Published by Elsevier Ireland Ltd.

  19. eCOMPAGT integrates mtDNA: import, validation and export of mitochondrial DNA profiles for population genetics, tumour dynamics and genotype-phenotype association studies.

    PubMed

    Weissensteiner, Hansi; Schönherr, Sebastian; Specht, Günther; Kronenberg, Florian; Brandstätter, Anita

    2010-03-09

    Mitochondrial DNA (mtDNA) is widely being used for population genetics, forensic DNA fingerprinting and clinical disease association studies. The recent past has uncovered severe problems with mtDNA genotyping, not only due to the genotyping method itself, but mainly to the post-lab transcription, storage and report of mtDNA genotypes. eCOMPAGT, a system to store, administer and connect phenotype data to all kinds of genotype data is now enhanced by the possibility of storing mtDNA profiles and allowing their validation, linking to phenotypes and export as numerous formats. mtDNA profiles can be imported from different sequence evaluation programs, compared between evaluations and their haplogroup affiliations stored. Furthermore, eCOMPAGT has been improved in its sophisticated transparency (support of MySQL and Oracle), security aspects (by using database technology) and the option to import, manage and store genotypes derived from various genotyping methods (SNPlex, TaqMan, and STRs). It is a software solution designed for project management, laboratory work and the evaluation process all-in-one. The extended mtDNA version of eCOMPAGT was designed to enable error-free post-laboratory data handling of human mtDNA profiles. This software is suited for small to medium-sized human genetic, forensic and clinical genetic laboratories. The direct support of MySQL and the improved database security options render eCOMPAGT a powerful tool to build an automated workflow architecture for several genotyping methods. eCOMPAGT is freely available at http://dbis-informatik.uibk.ac.at/ecompagt.

  20. eCOMPAGT integrates mtDNA: import, validation and export of mitochondrial DNA profiles for population genetics, tumour dynamics and genotype-phenotype association studies

    PubMed Central

    2010-01-01

    Background Mitochondrial DNA (mtDNA) is widely being used for population genetics, forensic DNA fingerprinting and clinical disease association studies. The recent past has uncovered severe problems with mtDNA genotyping, not only due to the genotyping method itself, but mainly to the post-lab transcription, storage and report of mtDNA genotypes. Description eCOMPAGT, a system to store, administer and connect phenotype data to all kinds of genotype data is now enhanced by the possibility of storing mtDNA profiles and allowing their validation, linking to phenotypes and export as numerous formats. mtDNA profiles can be imported from different sequence evaluation programs, compared between evaluations and their haplogroup affiliations stored. Furthermore, eCOMPAGT has been improved in its sophisticated transparency (support of MySQL and Oracle), security aspects (by using database technology) and the option to import, manage and store genotypes derived from various genotyping methods (SNPlex, TaqMan, and STRs). It is a software solution designed for project management, laboratory work and the evaluation process all-in-one. Conclusions The extended mtDNA version of eCOMPAGT was designed to enable error-free post-laboratory data handling of human mtDNA profiles. This software is suited for small to medium-sized human genetic, forensic and clinical genetic laboratories. The direct support of MySQL and the improved database security options render eCOMPAGT a powerful tool to build an automated workflow architecture for several genotyping methods. eCOMPAGT is freely available at http://dbis-informatik.uibk.ac.at/ecompagt. PMID:20214782

  1. DNA Commission of the International Society for Forensic Genetics (ISFG): Guidelines on the use of X-STRs in kinship analysis.

    PubMed

    Tillmar, Andreas O; Kling, Daniel; Butler, John M; Parson, Walther; Prinz, Mechthild; Schneider, Peter M; Egeland, Thore; Gusmão, Leonor

    2017-07-01

    Forensic genetic laboratories perform an increasing amount of genetic analyses of the X chromosome, in particular to solve complex cases of kinship analysis. For some biological relationships X-chromosomal markers can be more informative than autosomal markers, and there are a large number of markers, methods and databases that have been described for forensic use. Due to their particular mode of inheritance, and their physical location on a single chromosome, some specific considerations are required when estimating the weight of evidence for X-chromosomal marker DNA data. The DNA Commission of the International Society for Forensic Genetics (ISFG) hereby presents guidelines and recommendations for the use of X-chromosomal markers in kinship analysis with a special focus on the biostatistical evaluation. Linkage and linkage disequilibrium (association of alleles) are of special importance for such evaluations and these concepts and the implications for likelihood calculations are described in more detail. Furthermore it is important to use appropriate computer software that accounts for linkage and linkage disequilibrium among loci, as well as for mutations. Even though some software exist, there is still a need for further improvement of dedicated software. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Review: domestic animal forensic genetics - biological evidence, genetic markers, analytical approaches and challenges.

    PubMed

    Kanthaswamy, S

    2015-10-01

    This review highlights the importance of domestic animal genetic evidence sources, genetic testing, markers and analytical approaches as well as the challenges this field is facing in view of the de facto 'gold standard' human DNA identification. Because of the genetic similarity between humans and domestic animals, genetic analysis of domestic animal hair, saliva, urine, blood and other biological material has generated vital investigative leads that have been admitted into a variety of court proceedings, including criminal and civil litigation. Information on validated short tandem repeat, single nucleotide polymorphism and mitochondrial DNA markers and public access to genetic databases for forensic DNA analysis is becoming readily available. Although the fundamental aspects of animal forensic genetic testing may be reliable and acceptable, animal forensic testing still lacks the standardized testing protocols that human genetic profiling requires, probably because of the absence of monetary support from government agencies and the difficulty in promoting cooperation among competing laboratories. Moreover, there is a lack in consensus about how to best present the results and expert opinion to comply with court standards and bear judicial scrutiny. This has been the single most persistent challenge ever since the earliest use of domestic animal forensic genetic testing in a criminal case in the mid-1990s. Crime laboratory accreditation ensures that genetic test results have the courts' confidence. Because accreditation requires significant commitments of effort, time and resources, the vast majority of animal forensic genetic laboratories are not accredited nor are their analysts certified forensic examiners. The relevance of domestic animal forensic genetics in the criminal justice system is undeniable. However, further improvements are needed in a wide range of supporting resources, including standardized quality assurance and control protocols for sample handling, evidence testing, statistical analysis and reporting that meet the rules of scientific acceptance, reliability and human forensic identification standards. © 2015 Stichting International Foundation for Animal Genetics.

  3. The first successful use of a low stringency familial match in a French criminal investigation.

    PubMed

    Pham-Hoai, Emmanuel; Crispino, Frank; Hampikian, Greg

    2014-05-01

    We describe how a very simple application of familial searching resolved a decade-old, high-profile rape/murder in France. This was the first use of familial searching in a criminal case using the French STR DNA database, which contains approximately 1,800,000 profiles. When an unknown forensic profile (18 loci) was searched against the French arrestee/offender database using CODIS configured for a low stringency search, a single low stringency match was identified. This profile was attributed to the father of the man suspected to be the source of the semen recovered from the murder victim Elodie Kulik. The identification was confirmed using Y-chromosome DNA from the putative father, an STR profile from the mother, and finally a tissue sample from the exhumed body of the man who left the semen. Because of this identification, the investigators are now pursuing possible co-conspirators. © 2014 American Academy of Forensic Sciences.

  4. Social and ethical aspects of forensic genetics: A critical review.

    PubMed

    Williams, R; Wienroth, M

    2017-07-01

    This review describes the social and ethical responses to the history of innovations in forensic genetics and their application to criminal investigations. Following an outline of the three recurrent social perspectives that have informed these responses (crime management, due process, and genetic surveillance), it goes on to introduce the repertoire of ethical considerations by describing a series of key reports that have shaped subsequent commentaries on forensic DNA profiling and databasing. Four major ethical concerns form the focus of the remainder of the paper (dignity, privacy, justice, and social solidarity), and key features of forensic genetic practice are examined in the light of these concerns. The paper concludes with a discussion of the concept of "proportionality" as a resource for balancing the social and ethical risks and benefits of the use of forensic genetics in support of criminal justice. Copyright © 2017 Central Police University.

  5. Recommendations of the DNA Commission of the International Society for Forensic Genetics (ISFG) on quality control of autosomal Short Tandem Repeat allele frequency databasing (STRidER).

    PubMed

    Bodner, Martin; Bastisch, Ingo; Butler, John M; Fimmers, Rolf; Gill, Peter; Gusmão, Leonor; Morling, Niels; Phillips, Christopher; Prinz, Mechthild; Schneider, Peter M; Parson, Walther

    2016-09-01

    The statistical evaluation of autosomal Short Tandem Repeat (STR) genotypes is based on allele frequencies. These are empirically determined from sets of randomly selected human samples, compiled into STR databases that have been established in the course of population genetic studies. There is currently no agreed procedure of performing quality control of STR allele frequency databases, and the reliability and accuracy of the data are largely based on the responsibility of the individual contributing research groups. It has been demonstrated with databases of haploid markers (EMPOP for mitochondrial mtDNA, and YHRD for Y-chromosomal loci) that centralized quality control and data curation is essential to minimize error. The concepts employed for quality control involve software-aided likelihood-of-genotype, phylogenetic, and population genetic checks that allow the researchers to compare novel data to established datasets and, thus, maintain the high quality required in forensic genetics. Here, we present STRidER (http://strider.online), a publicly available, centrally curated online allele frequency database and quality control platform for autosomal STRs. STRidER expands on the previously established ENFSI DNA WG STRbASE and applies standard concepts established for haploid and autosomal markers as well as novel tools to reduce error and increase the quality of autosomal STR data. The platform constitutes a significant improvement and innovation for the scientific community, offering autosomal STR data quality control and reliable STR genotype estimates. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Launching the Greek forensic DNA database. The legal framework and arising ethical issues.

    PubMed

    Voultsos, Polychronis; Njau, Samuel; Tairis, Nikolaos; Psaroulis, Dimitrios; Kovatsi, Leda

    2011-11-01

    Since the creation of the first national DNA database in Europe in 1995, many European countries have legislated laws for initiating and regulating their own databases. The Greek government legislated a law in 2008, by which the National DNA Database of Greece was founded and regulated. According to this law, only DNA profiles from convicted criminals were recorded. Nevertheless, a year later, in 2009, the law was amended to permit the creation of an expanded database including innocent people and children. Unfortunately, the new law is very vague in many aspects and does not respect the principle of proportionality. Therefore, according to our opinion, it will soon need to be re-amended. Furthermore, prior to legislating the new law, there was no debate with the community itself in order to clarify what system would best suit Greece and what the citizens would be willing to accept. We present the current legal framework in Greece, we highlight issues that need to be clarified and we discuss possible ethical issues that may arise. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  7. Forensic parameters of the X-STR Decaplex system in Mexican populations.

    PubMed

    Mariscal Ramos, C; Martínez-Cortes, G; Ramos-González, B; Rangel-Villalobos, H

    2018-03-01

    We studied the X-STR decaplex system in 529 DNA female samples of Mexican populations from five geographic regions. Allele frequencies and forensic parameters were estimated in each region and in the pooled Mexican population. Genotype distribution by locus was in agreement with Hardy-Weinberg expectations in each Mexican population sample. Similarly, linkage equilibrium was demonstrated between pair of loci. Pairwise comparisons and genetic distances between Mexican, Iberoamerican and one African populations were estimated and graphically represented. Interestingly, a non-significant interpopulation differentiation was detected (Fst = 0.0021; p = .74389), which allows using a global Mexican database for forensic interpretation of X-STR genotypes. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Forensic timber identification: a case study of a CITES listed species, Gonystylus bancanus (Thymelaeaceae).

    PubMed

    Ng, Kevin Kit Siong; Lee, Soon Leong; Tnah, Lee Hong; Nurul-Farhanah, Zakaria; Ng, Chin Hong; Lee, Chai Ting; Tani, Naoki; Diway, Bibian; Lai, Pei Sing; Khoo, Eyen

    2016-07-01

    Illegal logging and smuggling of Gonystylus bancanus (Thymelaeaceae) poses a serious threat to this fragile valuable peat swamp timber species. Using G. bancanus as a case study, DNA markers were used to develop identification databases at the species, population and individual level. The species level database for Gonystylus comprised of an rDNA (ITS2) and two cpDNA (trnH-psbA and trnL) markers based on a 20 Gonystylus species database. When concatenated, taxonomic species recognition was achieved with a resolution of 90% (18 out of the 20 species). In addition, based on 17 natural populations of G. bancanus throughout West (Peninsular Malaysia) and East (Sabah and Sarawak) Malaysia, population and individual identification databases were developed using cpDNA and STR markers respectively. A haplotype distribution map for Malaysia was generated using six cpDNA markers, resulting in 12 unique multilocus haplotypes, from 24 informative intraspecific variable sites. These unique haplotypes suggest a clear genetic structuring of West and East regions. A simulation procedure based on the composition of the samples was used to test whether a suspected sample conformed to a given regional origin. Overall, the observed type I and II errors of the databases showed good concordance with the predicted 5% threshold which indicates that the databases were useful in revealing provenance and establishing conformity of samples from West and East Malaysia. Sixteen STRs were used to develop the DNA profiling databases for individual identification. Bayesian clustering analyses divided the 17 populations into two main genetic clusters, corresponding to the regions of West and East Malaysia. Population substructuring (K=2) was observed within each region. After removal of bias resulting from sampling effects and population subdivision, conservativeness tests showed that the West and East Malaysia databases were conservative. This suggests that both databases can be used independently for random match probability estimation within respective regions. The reliability of the databases was further determined by independent self-assignment tests based on the likelihood of each individual's multilocus genotype occurring in each identified population, genetic cluster and region with an average percentage of correctly assigned individuals of 54.80%, 99.60% and 100% respectively. Thus, after appropriate validation, the genetic identification databases developed for G. bancanus in this study could support forensic applications and help safeguard this valuable species into the future. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Searching mixed DNA profiles directly against profile databases.

    PubMed

    Bright, Jo-Anne; Taylor, Duncan; Curran, James; Buckleton, John

    2014-03-01

    DNA databases have revolutionised forensic science. They are a powerful investigative tool as they have the potential to identify persons of interest in criminal investigations. Routinely, a DNA profile generated from a crime sample could only be searched for in a database of individuals if the stain was from single contributor (single source) or if a contributor could unambiguously be determined from a mixed DNA profile. This meant that a significant number of samples were unsuitable for database searching. The advent of continuous methods for the interpretation of DNA profiles offers an advanced way to draw inferential power from the considerable investment made in DNA databases. Using these methods, each profile on the database may be considered a possible contributor to a mixture and a likelihood ratio (LR) can be formed. Those profiles which produce a sufficiently large LR can serve as an investigative lead. In this paper empirical studies are described to determine what constitutes a large LR. We investigate the effect on a database search of complex mixed DNA profiles with contributors in equal proportions with dropout as a consideration, and also the effect of an incorrect assignment of the number of contributors to a profile. In addition, we give, as a demonstration of the method, the results using two crime samples that were previously unsuitable for database comparison. We show that effective management of the selection of samples for searching and the interpretation of the output can be highly informative. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  10. Ethical issues across different fields of forensic science.

    PubMed

    Yadav, Praveen Kumar

    2017-01-01

    Many commentators have acknowledged the fact that the usual courtroom maxim to "tell the truth, the whole truth, and nothing but the truth" is not so easy to apply in practicality. In any given situation, what does the whole truth include? In case, the whole truth includes all the possible alternatives for a given situation, what should a forensic expert witness do when an important question is not asked by the prosecutor? Does the obligation to tell the whole truth mean that all possible, all probable, all reasonably probable, all highly probable, or only the most probable alternatives must be given in response to a question? In this paper, an attempt has been made to review the various ethical issues in different fields of forensic science, forensic psychology, and forensic DNA databases. Some of the ethical issues are common to all fields whereas some are field specific. These ethical issues are mandatory for ensuring high levels of reliability and credibility of forensic scientists.

  11. The "GeneTrustee": a universal identification system that ensures privacy and confidentiality for human genetic databases.

    PubMed

    Burnett, Leslie; Barlow-Stewart, Kris; Proos, Anné L; Aizenberg, Harry

    2003-05-01

    This article describes a generic model for access to samples and information in human genetic databases. The model utilises a "GeneTrustee", a third-party intermediary independent of the subjects and of the investigators or database custodians. The GeneTrustee model has been implemented successfully in various community genetics screening programs and has facilitated research access to genetic databases while protecting the privacy and confidentiality of research subjects. The GeneTrustee model could also be applied to various types of non-conventional genetic databases, including neonatal screening Guthrie card collections, and to forensic DNA samples.

  12. Application of the BioMek 2000 Laboratory Automation Workstation and the DNA IQ System to the extraction of forensic casework samples.

    PubMed

    Greenspoon, Susan A; Ban, Jeffrey D; Sykes, Karen; Ballard, Elizabeth J; Edler, Shelley S; Baisden, Melissa; Covington, Brian L

    2004-01-01

    Robotic systems are commonly utilized for the extraction of database samples. However, the application of robotic extraction to forensic casework samples is a more daunting task. Such a system must be versatile enough to accommodate a wide range of samples that may contain greatly varying amounts of DNA, but it must also pose no more risk of contamination than the manual DNA extraction methods. This study demonstrates that the BioMek 2000 Laboratory Automation Workstation, used in combination with the DNA IQ System, is versatile enough to accommodate the wide range of samples typically encountered by a crime laboratory. The use of a silica coated paramagnetic resin, as with the DNA IQ System, facilitates the adaptation of an open well, hands off, robotic system to the extraction of casework samples since no filtration or centrifugation steps are needed. Moreover, the DNA remains tightly coupled to the silica coated paramagnetic resin for the entire process until the elution step. A short pre-extraction incubation step is necessary prior to loading samples onto the robot and it is at this step that most modifications are made to accommodate the different sample types and substrates commonly encountered with forensic evidentiary samples. Sexual assault (mixed stain) samples, cigarette butts, blood stains, buccal swabs, and various tissue samples were successfully extracted with the BioMek 2000 Laboratory Automation Workstation and the DNA IQ System, with no evidence of contamination throughout the extensive validation studies reported here.

  13. Dangers resulting from DNA profiling of biological materials derived from patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT) with regard to forensic genetic analysis.

    PubMed

    Jacewicz, R; Lewandowski, K; Rupa-Matysek, J; Jędrzejczyk, M; Berent, J

    The study documents the risk that comes with DNA analysis of materials derived from patients after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in forensic genetics. DNA chimerism was studied in 30 patients after allo-HSCT, based on techniques applied in contemporary forensic genetics, i.e. real-time PCR and multiplex PCR-STR with the use of autosomal DNA as well as Y-DNA markers. The results revealed that the DNA profile of the recipient's blood was identical with the donor's in the majority of cases. Therefore, blood analysis can lead to false conclusions in personal identification as well as kinship analysis. An investigation of buccal swabs revealed a mixture of DNA in the majority of recipients. Consequently, personal identification on the basis of stain analysis of the same origin may be impossible. The safest (but not ideal) material turned out to be the hair root. Its analysis based on autosomal DNA revealed 100% of the recipient's profile. However, an analysis based on Y-chromosome markers performed in female allo-HSCT recipients with male donors demonstrated the presence of donor DNA in hair cells - similarly to the blood and buccal swabs. In the light of potential risks arising from DNA profiling of biological materials derived from persons after allotransplantation in judicial aspects, certain procedures were proposed to eliminate such dangers. The basic procedures include abandoning the approach based exclusively on blood collection, both for kinship analysis and personal identification; asking persons who are to be tested about their history of allo-HSCT before sample collection and profile entry in the DNA database, and verification of DNA profiling based on hair follicles in uncertain cases.

  14. Genotyping and interpretation of STR-DNA: Low-template, mixtures and database matches-Twenty years of research and development.

    PubMed

    Gill, Peter; Haned, Hinda; Bleka, Oyvind; Hansson, Oskar; Dørum, Guro; Egeland, Thore

    2015-09-01

    The introduction of Short Tandem Repeat (STR) DNA was a revolution within a revolution that transformed forensic DNA profiling into a tool that could be used, for the first time, to create National DNA databases. This transformation would not have been possible without the concurrent development of fluorescent automated sequencers, combined with the ability to multiplex several loci together. Use of the polymerase chain reaction (PCR) increased the sensitivity of the method to enable the analysis of a handful of cells. The first multiplexes were simple: 'the quad', introduced by the defunct UK Forensic Science Service (FSS) in 1994, rapidly followed by a more discriminating 'six-plex' (Second Generation Multiplex) in 1995 that was used to create the world's first national DNA database. The success of the database rapidly outgrew the functionality of the original system - by the year 2000 a new multiplex of ten-loci was introduced to reduce the chance of adventitious matches. The technology was adopted world-wide, albeit with different loci. The political requirement to introduce pan-European databases encouraged standardisation - the development of European Standard Set (ESS) of markers comprising twelve-loci is the latest iteration. Although development has been impressive, the methods used to interpret evidence have lagged behind. For example, the theory to interpret complex DNA profiles (low-level mixtures), had been developed fifteen years ago, but only in the past year or so, are the concepts starting to be widely adopted. A plethora of different models (some commercial and others non-commercial) have appeared. This has led to a confusing 'debate' about the 'best' to use. The different models available are described along with their advantages and disadvantages. A section discusses the development of national DNA databases, along with details of an associated controversy to estimate the strength of evidence of matches. Current methodology is limited to searches of complete profiles - another example where the interpretation of matches has not kept pace with development of theory. STRs have also transformed the area of Disaster Victim Identification (DVI) which frequently requires kinship analysis. However, genotyping efficiency is complicated by complex, degraded DNA profiles. Finally, there is now a detailed understanding of the causes of stochastic effects that cause DNA profiles to exhibit the phenomena of drop-out and drop-in, along with artefacts such as stutters. The phenomena discussed include: heterozygote balance; stutter; degradation; the effect of decreasing quantities of DNA; the dilution effect. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Feline mitochondrial DNA sampling for forensic analysis: when enough is enough!

    PubMed

    Grahn, Robert A; Alhaddad, Hasan; Alves, Paulo C; Randi, Ettore; Waly, Nashwa E; Lyons, Leslie A

    2015-05-01

    Pet hair has a demonstrated value in resolving legal issues. Cat hair is chronically shed and it is difficult to leave a home with cats without some level of secondary transfer. The power of cat hair as an evidentiary resource may be underused because representative genetic databases are not available for exclusionary purposes. Mitochondrial control region databases are highly valuable for hair analyses and have been developed for the cat. In a representative worldwide data set, 83% of domestic cat mitotypes belong to one of twelve major types. Of the remaining 17%, 7.5% are unique within the published 1394 sample database. The current research evaluates the sample size necessary to establish a representative population for forensic comparison of the mitochondrial control region for the domestic cat. For most worldwide populations, randomly sampling 50 unrelated local individuals will achieve saturation at 95%. The 99% saturation is achieved by randomly sampling 60-170 cats, depending on the numbers of mitotypes available in the population at large. Likely due to the recent domestication of the cat and minimal localized population substructure, fewer cats are needed to meet mitochondria DNA control region database practical saturation than for humans or dogs. Coupled with the available worldwide feline control region database of nearly 1400 cats, minimal local sampling will be required to establish an appropriate comparative representative database and achieve significant exclusionary power. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Soil characterisation by bacterial community analysis for forensic applications: A quantitative comparison of environmental technologies.

    PubMed

    Habtom, Habteab; Demanèche, Sandrine; Dawson, Lorna; Azulay, Chen; Matan, Ofra; Robe, Patrick; Gafny, Ron; Simonet, Pascal; Jurkevitch, Edouard; Pasternak, Zohar

    2017-01-01

    The ubiquity and transferability of soil makes it a resource for the forensic investigator, as it can provide a link between agents and scenes. However, the information contained in soils, such as chemical compounds, physical particles or biological entities, is seldom used in forensic investigations; due mainly to the associated costs, lack of available expertise, and the lack of soil databases. The microbial DNA in soil is relatively easy to access and analyse, having thus the potential to provide a powerful means for discriminating soil samples or linking them to a common origin. We compared the effectiveness and reliability of multiple methods and genes for bacterial characterisation in the differentiation of soil samples: ribosomal intergenic spacer analysis (RISA), terminal restriction fragment length polymorphism (TRFLP) of the rpoB gene, and five methods using the 16S rRNA gene: phylogenetic microarrays, TRFLP, and high throughput sequencing with Roche 454, Illumina MiSeq and IonTorrent PGM platforms. All these methods were also compared to long-chain hydrocarbons (n-alkanes) and fatty alcohol profiling of the same soil samples. RISA, 16S TRFLP and MiSeq performed best, reliably and significantly discriminating between adjacent, similar soil types. As TRFLP employs the same capillary electrophoresis equipment and procedures used to analyse human DNA, it is readily available for use in most forensic laboratories. TRFLP was optimized for forensic usage in five parameters: choice of primer pair, fluorescent tagging, concentrating DNA after digestion, number of PCR amplifications per sample and number of capillary electrophoresis runs per PCR amplification. This study shows that molecular microbial ecology methodologies are robust in discriminating between soil samples, illustrating their potential usage as an evaluative forensic tool. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  17. The use of forensic DNA analysis in humanitarian forensic action: The development of a set of international standards.

    PubMed

    Goodwin, William H

    2017-09-01

    DNA analysis was first applied to the identification of victims of armed conflicts and other situations of violence (ACOSV) in the mid-1990s, starting in South America and the Balkans. Argentina was the first country to establish a genetic database specifically developed to identify disappeared children. Following on from these programs the early 2000s marked major programs, using a largely DNA-led approach, identifying missing persons in the Balkans and following the attack on the World Trade Center in New York. These two identification programs significantly expanded the magnitude of events to which DNA analysis was used to help provide the identity of missing persons. Guidelines developed by Interpol (2014) [1] related to best practice for identification of human remains following DVI type scenarios have been widely disseminated around the forensic community; in numerous cases these guidelines have been adopted or incorporated into national guidelines/standards/practice. However, given the complexity of many humanitarian contexts in which forensic science is employed there is a lack of internationally accepted guidelines, related to these contexts, for authorities to reference. In response the Argentine government's Human Rights Division in the Ministry of Foreign Affairs and Worship (MREC) proposed that the United Nations (UN) should promote best practice in the use of forensic genetics in humanitarian forensic action: this was adopted by the UN in Resolutions A/HRC/RES/10/26 and A/HRC/RES/15/5. Following on from the adoption of the resolutions MREC has coordinated, with the support of the International Committee of the Red Cross (ICRC), the drafting of a set of guidelines (MREC, ICRC, 2014) [2], with input from national and international agencies. To date the guidelines have been presented to South America's MERCOSUR and the UN and have been disseminated to interested parties. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. [Application of DNA labeling technology in forensic botany].

    PubMed

    Znang, Xian; Li, Jing-Lin; Zhang, Xiang-Yu

    2008-12-01

    Forensic botany is a study of judicial plant evidence. Recently, researches on DNA labeling technology have been a mainstream of forensic botany. The article systematically reviews various types of DNA labeling techniques in forensic botany with enumerated practical cases, as well as the potential forensic application of each individual technique. The advantages of the DNA labeling technology over traditional morphological taxonomic methods are also summarized.

  19. Concept for estimating mitochondrial DNA haplogroups using a maximum likelihood approach (EMMA)☆

    PubMed Central

    Röck, Alexander W.; Dür, Arne; van Oven, Mannis; Parson, Walther

    2013-01-01

    The assignment of haplogroups to mitochondrial DNA haplotypes contributes substantial value for quality control, not only in forensic genetics but also in population and medical genetics. The availability of Phylotree, a widely accepted phylogenetic tree of human mitochondrial DNA lineages, led to the development of several (semi-)automated software solutions for haplogrouping. However, currently existing haplogrouping tools only make use of haplogroup-defining mutations, whereas private mutations (beyond the haplogroup level) can be additionally informative allowing for enhanced haplogroup assignment. This is especially relevant in the case of (partial) control region sequences, which are mainly used in forensics. The present study makes three major contributions toward a more reliable, semi-automated estimation of mitochondrial haplogroups. First, a quality-controlled database consisting of 14,990 full mtGenomes downloaded from GenBank was compiled. Together with Phylotree, these mtGenomes serve as a reference database for haplogroup estimates. Second, the concept of fluctuation rates, i.e. a maximum likelihood estimation of the stability of mutations based on 19,171 full control region haplotypes for which raw lane data is available, is presented. Finally, an algorithm for estimating the haplogroup of an mtDNA sequence based on the combined database of full mtGenomes and Phylotree, which also incorporates the empirically determined fluctuation rates, is brought forward. On the basis of examples from the literature and EMPOP, the algorithm is not only validated, but both the strength of this approach and its utility for quality control of mitochondrial haplotypes is also demonstrated. PMID:23948335

  20. FastID: Extremely Fast Forensic DNA Comparisons

    DTIC Science & Technology

    2017-05-19

    FastID: Extremely Fast Forensic DNA Comparisons Darrell O. Ricke, PhD Bioengineering Systems & Technologies Massachusetts Institute of...Technology Lincoln Laboratory Lexington, MA USA Darrell.Ricke@ll.mit.edu Abstract—Rapid analysis of DNA forensic samples can have a critical impact on...time sensitive investigations. Analysis of forensic DNA samples by massively parallel sequencing is creating the next gold standard for DNA

  1. From forensic epigenetics to forensic epigenomics: broadening DNA investigative intelligence.

    PubMed

    Vidaki, Athina; Kayser, Manfred

    2017-12-21

    Human genetic variation is a major resource in forensics, but does not allow all forensically relevant questions to be answered. Some questions may instead be addressable via epigenomics, as the epigenome acts as an interphase between the fixed genome and the dynamic environment. We envision future forensic applications of DNA methylation analysis that will broaden DNA-based forensic intelligence. Together with genetic prediction of appearance and biogeographic ancestry, epigenomic lifestyle prediction is expected to increase the ability of police to find unknown perpetrators of crime who are not identifiable using current forensic DNA profiling.

  2. A ranking index for quality assessment of forensic DNA profiles forensic DNA profiles

    PubMed Central

    2010-01-01

    Background Assessment of DNA profile quality is vital in forensic DNA analysis, both in order to determine the evidentiary value of DNA results and to compare the performance of different DNA analysis protocols. Generally the quality assessment is performed through manual examination of the DNA profiles based on empirical knowledge, or by comparing the intensities (allelic peak heights) of the capillary electrophoresis electropherograms. Results We recently developed a ranking index for unbiased and quantitative quality assessment of forensic DNA profiles, the forensic DNA profile index (FI) (Hedman et al. Improved forensic DNA analysis through the use of alternative DNA polymerases and statistical modeling of DNA profiles, Biotechniques 47 (2009) 951-958). FI uses electropherogram data to combine the intensities of the allelic peaks with the balances within and between loci, using Principal Components Analysis. Here we present the construction of FI. We explain the mathematical and statistical methodologies used and present details about the applied data reduction method. Thereby we show how to adapt the ranking index for any Short Tandem Repeat-based forensic DNA typing system through validation against a manual grading scale and calibration against a specific set of DNA profiles. Conclusions The developed tool provides unbiased quality assessment of forensic DNA profiles. It can be applied for any DNA profiling system based on Short Tandem Repeat markers. Apart from crime related DNA analysis, FI can therefore be used as a quality tool in paternal or familial testing as well as in disaster victim identification. PMID:21062433

  3. Application of forensic DNA testing in the legal system.

    PubMed

    Primorac, D; Schanfield, M S

    2000-03-01

    DNA technology has taken an irreplaceable position in the field of the forensic sciences. Since 1985, when Peter Gill and Alex Jeffreys first applied DNA technology to forensic problems, to the present, more than 50,000 cases worldwide have been solved through the use of DNA based technology. Although the development of DNA typing in forensic science has been extremely rapid, today we are witnessing a new era of DNA technology including automation and miniaturization. In forensic science, DNA analysis has become "the new form of scientific evidence" and has come under public scrutiny and the demand to show competence. More and more courts admit the DNA based evidence. We believe that in the near future this technology will be generally accepted in the legal system. There are two main applications of DNA analysis in forensic medicine: criminal investigation and paternity testing. In this article we present background information on DNA, human genetics, and the application of DNA analysis to legal problems, as well as the commonly applied respective mathematics.

  4. [DNA extraction from bones and teeth using AutoMate Express forensic DNA extraction system].

    PubMed

    Gao, Lin-Lin; Xu, Nian-Lai; Xie, Wei; Ding, Shao-Cheng; Wang, Dong-Jing; Ma, Li-Qin; Li, You-Ying

    2013-04-01

    To explore a new method in order to extract DNA from bones and teeth automatically. Samples of 33 bones and 15 teeth were acquired by freeze-mill method and manual method, respectively. DNA materials were extracted and quantified from the triturated samples by AutoMate Express forensic DNA extraction system. DNA extraction from bones and teeth were completed in 3 hours using the AutoMate Express forensic DNA extraction system. There was no statistical difference between the two methods in the DNA concentration of bones. Both bones and teeth got the good STR typing by freeze-mill method, and the DNA concentration of teeth was higher than those by manual method. AutoMate Express forensic DNA extraction system is a new method to extract DNA from bones and teeth, which can be applied in forensic practice.

  5. Genetic perspective of uniparental mitochondrial DNA landscape on the Punjabi population, Pakistan.

    PubMed

    Bhatti, Shahzad; Abbas, Sana; Aslamkhan, Muhammad; Attimonelli, Marcella; Trinidad, Magali Segundo; Aydin, Hikmet Hakan; de Souza, Erica Martinha Silva; Gonzalez, Gerardo Rodriguez

    2017-07-26

    To investigate the uniparental genetic structure of the Punjabi population from mtDNA aspect and to set up an appropriate mtDNA forensic database, we studied maternally unrelated Punjabi (N = 100) subjects from two caste groups (i.e. Arain and Gujar) belonging to territory of Punjab. The complete control region was elucidated by Sanger sequencing and the subsequent 58 different haplotypes were designated into appropriate haplogroups according to the most recently updated mtDNA phylogeny. We found a homogenous dispersal of Eurasian haplogroup uniformity among the Punjab Province and exhibited a strong connotation with the European populations. Punjabi castes are primarily a composite of substantial South Asian, East Asian and West Eurasian lineages. Moreover, for the first time we have defined the newly sub-haplogroup M52b1 characterized by 16223 T, 16275 G and 16438 A in Gujar caste. The vast array of mtDNA variants displayed in this study suggested that the haplogroup composition radiates signals of extensive genetic conglomeration, population admixture and demographic expansion that was equipped with diverse origin, whereas matrilineal gene pool was phylogeographically homogenous across the Punjab. This context was further fully acquainted with the facts supported by PCA scatterplot that Punjabi population clustered with South Asian populations. Finally, the high power of discrimination (0.8819) and low random match probability (0.0085%) proposed a worthy contribution of mtDNA control region dataset as a forensic database that considered a gold standard of today to get deeper insight into the genetic ancestry of contemporary matrilineal phylogeny.

  6. Application of DNA-based methods in forensic entomology.

    PubMed

    Wells, Jeffrey D; Stevens, Jamie R

    2008-01-01

    A forensic entomological investigation can benefit from a variety of widely practiced molecular genotyping methods. The most commonly used is DNA-based specimen identification. Other applications include the identification of insect gut contents and the characterization of the population genetic structure of a forensically important insect species. The proper application of these procedures demands that the analyst be technically expert. However, one must also be aware of the extensive list of standards and expectations that many legal systems have developed for forensic DNA analysis. We summarize the DNA techniques that are currently used in, or have been proposed for, forensic entomology and review established genetic analyses from other scientific fields that address questions similar to those in forensic entomology. We describe how accepted standards for forensic DNA practice and method validation are likely to apply to insect evidence used in a death or other forensic entomological investigation.

  7. mtDNA sequence diversity of Hazara ethnic group from Pakistan.

    PubMed

    Rakha, Allah; Fatima; Peng, Min-Sheng; Adan, Atif; Bi, Rui; Yasmin, Memona; Yao, Yong-Gang

    2017-09-01

    The present study was undertaken to investigate mitochondrial DNA (mtDNA) control region sequences of Hazaras from Pakistan, so as to generate mtDNA reference database for forensic casework in Pakistan and to analyze phylogenetic relationship of this particular ethnic group with geographically proximal populations. Complete mtDNA control region (nt 16024-576) sequences were generated through Sanger Sequencing for 319 Hazara individuals from Quetta, Baluchistan. The population sample set showed a total of 189 distinct haplotypes, belonging mainly to West Eurasian (51.72%), East & Southeast Asian (29.78%) and South Asian (18.50%) haplogroups. Compared with other populations from Pakistan, the Hazara population had a relatively high haplotype diversity (0.9945) and a lower random match probability (0.0085). The dataset has been incorporated into EMPOP database under accession number EMP00680. The data herein comprises the largest, and likely most thoroughly examined, control region mtDNA dataset from Hazaras of Pakistan. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. The Polish Genetic Database of Victims of Totalitarianisms.

    PubMed

    Ossowski, A; Kuś, M; Kupiec, T; Bykowska, M; Zielińska, G; Jasiński, M E; March, A L

    2016-01-01

    This paper describes the creation of the Polish Genetic Database of Victims of Totalitarianism and the first research conducted under this project. On September 28th 2012, the Pomeranian Medical University in Szczecin and the Institute of National Remembrance-Commission for Prosecution of Crimes against the Polish Nation agreed to support the creation of the Polish Genetic Database of Victims of Totalitarianism (PBGOT, www.pbgot.pl). The purpose was to employ state-of-the-art methods of forensic genetics to identify the remains of unidentified victims of Communist and Nazi totalitarian regimes. The database was designed to serve as a central repository of genetic information of the victim's DNA and that of the victim's nearest living relatives, with the goal of making a positive identification of the victim. Along the way, PGBOT encountered several challenges. First, extracting useable DNA samples from the remains of individuals who had been buried for over half a century required forensic geneticists to create special procedures and protocols. Second, obtaining genetic reference material and historical information from the victim's closest relatives was both problematic and urgent. The victim's nearest living relatives were part of a dying generation, and the opportunity to obtain the best genetic and historical information about the victims would soon die with them. For this undertaking, PGBOT assembled a team of historians, archaeologists, forensic anthropologists, and forensic geneticists from several European research institutions. The field work was divided into five broad categories: (1) exhumation of victim remains and storing their biological material for later genetic testing; (2) researching archives and historical data for a more complete profile of those killed or missing and the families that lost them; (3) locating the victim's nearest relatives to obtain genetic reference samples (swabs), (4) entering the genetic data from both victims and family members into a common database; (5) making a conclusive, final identification of the victim. PGBOT's first project was to identify victims of the Communist regime buried in hidden mass graves in the Powązki Military Cemetery in Warsaw. Throughout 2012 and 2013, PGBOT carried out archaeological exhumations in the Powązki Military Cemetery that resulted in the recovery of the skeletal remains of 194 victims in several mass graves. Of the 194 sets of remains, more than 50 victims have been successfully matched and identified through genetic evidence. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  9. High-Resolution Melting (HRM) of Hypervariable Mitochondrial DNA Regions for Forensic Science.

    PubMed

    Dos Santos Rocha, Alípio; de Amorim, Isis Salviano Soares; Simão, Tatiana de Almeida; da Fonseca, Adenilson de Souza; Garrido, Rodrigo Grazinoli; Mencalha, Andre Luiz

    2018-03-01

    Forensic strategies commonly are proceeding by analysis of short tandem repeats (STRs); however, new additional strategies have been proposed for forensic science. Thus, this article standardized the high-resolution melting (HRM) of DNA for forensic analyzes. For HRM, mitochondrial DNA (mtDNA) from eight individuals were extracted from mucosa swabs by DNAzol reagent, samples were amplified by PCR and submitted to HRM analysis to identify differences in hypervariable (HV) regions I and II. To confirm HRM, all PCR products were DNA sequencing. The data suggest that is possible discriminate DNA from different samples by HRM curves. Also, uncommon dual-dissociation was identified in a single PCR product, increasing HRM analyzes by evaluation of melting peaks. Thus, HRM is accurate and useful to screening small differences in HVI and HVII regions from mtDNA and increase the efficiency of laboratory routines based on forensic genetics. © 2017 American Academy of Forensic Sciences.

  10. Forensic DNA testing.

    PubMed

    Butler, John M

    2011-12-01

    Forensic DNA testing has a number of applications, including parentage testing, identifying human remains from natural or man-made disasters or terrorist attacks, and solving crimes. This article provides background information followed by an overview of the process of forensic DNA testing, including sample collection, DNA extraction, PCR amplification, short tandem repeat (STR) allele separation and sizing, typing and profile interpretation, statistical analysis, and quality assurance. The article concludes with discussions of possible problems with the data and other forensic DNA testing techniques.

  11. Patterns of exchange of forensic DNA data in the European Union through the Prüm system.

    PubMed

    Santos, Filipe; Machado, Helena

    2017-07-01

    This paper presents a study of the 5-year operation (2011-2015) of the transnational exchange of forensic DNA data between Member States of the European Union (EU) for the purpose of combating cross-border crime and terrorism within the so-called Prüm system. This first systematisation of the full official statistical dataset provides an overall assessment of the match figures and patterns of operation of the Prüm system for DNA exchange. These figures and patterns are analysed in terms of the differentiated contributions by participating EU Member States. The data suggest a trend for West and Central European countries to concentrate the majority of Prüm matches, while DNA databases of Eastern European countries tend to contribute with profiles of people that match stains in other countries. In view of the necessary transparency and accountability of the Prüm system, more extensive and informative statistics would be an important contribution to the assessment of its functioning and societal benefits. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  12. Effective use of forensic science in volume crime investigations: identifying recurring themes in the literature.

    PubMed

    Ludwig, Anika; Fraser, Jim

    2014-01-01

    New scientific, technological and legal developments, particularly the introduction of national databases for DNA and fingerprints, have led to increased use of forensic science in the investigation of crime. There is an assumption, and in some instances specific assertions, that such developments bring improvements either in broad criminal justice terms or more narrowly in terms of economic or practical efficiencies. The underlying presumption is that the new technological opportunities will be understood and effectively implemented. This research investigates whether such increases in activity have also been accompanied by improvements in the effective use of forensic science. A systematic review of thirty-six reports published (predominantly in England and Wales) since the 1980s, which have considered the use of forensic science in the investigation of volume crimes, was carried out. These reports have identified a number of recurrent themes that influenced how effectively forensic science was used in investigations. The themes identified included forensic knowledge and training of investigators, communication and information exchange between specialists and investigators, timeliness of forensic results, interagency relationships and deployment of crime scene examiner resources. The research findings suggest that these factors continue to hinder the effective use of forensic science despite technological advances and this paper considers their potential causes. © 2013.

  13. Optimized mtDNA Control Region Primer Extension Capture Analysis for Forensically Relevant Samples and Highly Compromised mtDNA of Different Age and Origin

    PubMed Central

    Eduardoff, Mayra; Xavier, Catarina; Strobl, Christina; Casas-Vargas, Andrea; Parson, Walther

    2017-01-01

    The analysis of mitochondrial DNA (mtDNA) has proven useful in forensic genetics and ancient DNA (aDNA) studies, where specimens are often highly compromised and DNA quality and quantity are low. In forensic genetics, the mtDNA control region (CR) is commonly sequenced using established Sanger-type Sequencing (STS) protocols involving fragment sizes down to approximately 150 base pairs (bp). Recent developments include Massively Parallel Sequencing (MPS) of (multiplex) PCR-generated libraries using the same amplicon sizes. Molecular genetic studies on archaeological remains that harbor more degraded aDNA have pioneered alternative approaches to target mtDNA, such as capture hybridization and primer extension capture (PEC) methods followed by MPS. These assays target smaller mtDNA fragment sizes (down to 50 bp or less), and have proven to be substantially more successful in obtaining useful mtDNA sequences from these samples compared to electrophoretic methods. Here, we present the modification and optimization of a PEC method, earlier developed for sequencing the Neanderthal mitochondrial genome, with forensic applications in mind. Our approach was designed for a more sensitive enrichment of the mtDNA CR in a single tube assay and short laboratory turnaround times, thus complying with forensic practices. We characterized the method using sheared, high quantity mtDNA (six samples), and tested challenging forensic samples (n = 2) as well as compromised solid tissue samples (n = 15) up to 8 kyrs of age. The PEC MPS method produced reliable and plausible mtDNA haplotypes that were useful in the forensic context. It yielded plausible data in samples that did not provide results with STS and other MPS techniques. We addressed the issue of contamination by including four generations of negative controls, and discuss the results in the forensic context. We finally offer perspectives for future research to enable the validation and accreditation of the PEC MPS method for final implementation in forensic genetic laboratories. PMID:28934125

  14. Human Chromosome Y and Haplogroups; introducing YDHS Database.

    PubMed

    Tiirikka, Timo; Moilanen, Jukka S

    2015-12-01

    As the high throughput sequencing efforts generate more biological information, scientists from different disciplines are interpreting the polymorphisms that make us unique. In addition, there is an increasing trend in general public to research their own genealogy, find distant relatives and to know more about their biological background. Commercial vendors are providing analyses of mitochondrial and Y-chromosomal markers for such purposes. Clearly, an easy-to-use free interface to the existing data on the identified variants would be in the interest of general public and professionals less familiar with the field. Here we introduce a novel metadatabase YDHS that aims to provide such an interface for Y-chromosomal DNA (Y-DNA) haplogroups and sequence variants. The database uses ISOGG Y-DNA tree as the source of mutations and haplogroups and by using genomic positions of the mutations the database links them to genes and other biological entities. YDHS contains analysis tools for deeper Y-SNP analysis. YDHS addresses the shortage of Y-DNA related databases. We have tested our database using a set of different cases from literature ranging from infertility to autism. The database is at http://www.semanticgen.net/ydhs Y-chromosomal DNA (Y-DNA) haplogroups and sequence variants have not been in the scientific limelight, excluding certain specialized fields like forensics, mainly because there is not much freely available information or it is scattered in different sources. However, as we have demonstrated Y-SNPs do play a role in various cases on the haplogroup level and it is possible to create a free Y-DNA dedicated bioinformatics resource.

  15. DNA Fingerprinting Using PCR: A Practical Forensic Science Activity

    ERIC Educational Resources Information Center

    Choi, Hyun-Jung; Ahn, Jung Hoon; Ko, Minsu

    2008-01-01

    This paper describes a forensic science simulation programme applicable for use in colleges. Students were asked to find a putative suspect by DNA fingerprinting using a simple protocol developed in this study. DNA samples were obtained from a hair root and a drop of blood, common sources of DNA in forensic science. The DNA fingerprinting protocol…

  16. Forensic Analysis of Human DNA from Samples Contamined with Bioweapons Agents

    DTIC Science & Technology

    2011-10-01

    Forensic analysis of human DNA from samples contaminated with bioweapons agents Jason Timbers Kathryn Wright Royal Canadian Mounted...Police Forensic Science and Identification Service Prepared By: Royal Canadian Mounted Police RCMP Forensic Science Identification Services... Royal Canadian Mounted Police Forensic Science and Identification Service Prepared By: Royal Canadian Mounted Police RCMP Forensic Science

  17. Microbial forensics: fiber optic microarray subtyping of Bacillus anthracis

    NASA Astrophysics Data System (ADS)

    Shepard, Jason R. E.

    2009-05-01

    The past decade has seen increased development and subsequent adoption of rapid molecular techniques involving DNA analysis for detection of pathogenic microorganisms, also termed microbial forensics. The continued accumulation of microbial sequence information in genomic databases now better positions the field of high-throughput DNA analysis to proceed in a more manageable fashion. The potential to build off of these databases exists as technology continues to develop, which will enable more rapid, cost effective analyses. This wealth of genetic information, along with new technologies, has the potential to better address some of the current problems and solve the key issues involved in DNA analysis of pathogenic microorganisms. To this end, a high density fiber optic microarray has been employed, housing numerous DNA sequences simultaneously for detection of various pathogenic microorganisms, including Bacillus anthracis, among others. Each organism is analyzed with multiple sequences and can be sub-typed against other closely related organisms. For public health labs, real-time PCR methods have been developed as an initial preliminary screen, but culture and growth are still considered the gold standard. Technologies employing higher throughput than these standard methods are better suited to capitalize on the limitless potential garnered from the sequence information. Microarray analyses are one such format positioned to exploit this potential, and our array platform is reusable, allowing repetitive tests on a single array, providing an increase in throughput and decrease in cost, along with a certainty of detection, down to the individual strain level.

  18. ISFG: recommendations regarding the use of non-human (animal) DNA in forensic genetic investigations.

    PubMed

    Linacre, A; Gusmão, L; Hecht, W; Hellmann, A P; Mayr, W R; Parson, W; Prinz, M; Schneider, P M; Morling, N

    2011-11-01

    The use of non-human DNA typing in forensic science investigations, and specifically that from animal DNA, is ever increasing. The term animal DNA in this document refers to animal species encountered in a forensic science examination but does not include human DNA. Non-human DNA may either be: the trade and possession of a species, or products derived from a species, which is contrary to legislation; as evidence where the crime is against a person or property; instances of animal cruelty; or where the animal is the offender. The first instance is addressed by determining the species present, and the other scenarios can often be addressed by assigning a DNA sample to a particular individual organism. Currently there is little standardization of methodologies used in the forensic analysis of animal DNA or in reporting styles. The recommendations in this document relate specifically to animal DNA that is integral to a forensic science investigation and are not relevant to the breeding of animals for commercial purposes. This DNA commission was formed out of discussions at the International Society for Forensic Genetics 23rd Congress in Buenos Aires to outline recommendations on the use of non-human DNA in a forensic science investigation. Due to the scope of non-human DNA typing that is possible, the remit of this commission is confined to animal DNA typing only. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  19. Application of STR markers in wildlife forensic casework involving Australian black-cockatoos (Calyptorhynchus spp.).

    PubMed

    White, Nicole E; Dawson, Rick; Coghlan, Megan L; Tridico, Silvana R; Mawson, Peter R; Haile, James; Bunce, Michael

    2012-09-01

    Parrots and cockatoos are highly prized aviary birds and the demands for such species has fuelled their illegal trade and harvest from the wild. Here we report on three forensic case studies involving black-cockatoos (Calyptorhynchus spp.) endemic to Australia. These cases involve suspected poaching and illegal killing of endangered red- and white-tailed black-cockatoos. Through the prior development of 20 polymorphic microsatellite loci and population databases for white- and red-tailed black-cockatoos, the tools are available to conduct high-resolution paternity and individual identity testing. In one case, we matched a red-tailed black-cockatoo nestling to a tree hollow from which it was poached through the use of DNA from eggshell recovered from the nest. For the second case, we utilized our provenance population database (nest sites), and identified the kinship and geographic origin of a white-tailed black-cockatoo, which was illegally harvested from the wild. The third case determined the number individual white-tailed black-cockatoos allegedly shot at a fruit grower's orchard from body part remains. These genetic investigations highlight the significance and statistical confidence of DNA profiling and associated databases for endangered taxa, such as exotic birds. Our cockatoo population databases are the first of their kind in Australia, and demonstrate the efficacy of such approaches to identify such illegal activity. With a robust set of genetic markers and methodologies in place, we aim to broaden our population databases to include other cockatoo species of conservation concern. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  20. Mitochondrial DNA identification of game and harvested freshwater fish species.

    PubMed

    Kyle, C J; Wilson, C C

    2007-02-14

    The use of DNA in forensics has grown rapidly for human applications along with the concomitant development of bioinformatics and demographic databases to help fully realize the potential of this molecular information. Similar techniques are also used routinely in many wildlife cases, such as species identification in food products, poaching and the illegal trade of endangered species. The use of molecular techniques in forensic cases related to wildlife and the development of associated databases has, however, mainly focused on large mammals with the exception of a few high-profile species. There is a need to develop similar databases for aquatic species for fisheries enforcement, given the large number of exploited and endangered fish species, the intensity of exploitation, and challenges in identifying species and their derived products. We sequenced a 500bp fragment of the mitochondrial cytochrome b gene from representative individuals from 26 harvested fish taxa from Ontario, Canada, focusing on species that support major commercial and recreational fisheries. Ontario provides a unique model system for the development of a fish species database, as the province contains an evolutionarily diverse array of freshwater fish families representing more than one third of all freshwater fish in Canada. Inter- and intraspecific sequence comparisons using phylogenetic analysis and a BLAST search algorithm provided rigorous statistical metrics for species identification. This methodology and these data will aid in fisheries enforcement, providing a tool to easily and accurately identify fish species in enforcement investigations that would have otherwise been difficult or impossible to pursue.

  1. Genetics and Forensics: Making the National DNA Database

    PubMed Central

    Johnson, Paul; Williams, Robin; Martin, Paul

    2005-01-01

    This paper is based on a current study of the growing police use of the epistemic authority of molecular biology for the identification of criminal suspects in support of crime investigation. It discusses the development of DNA profiling and the establishment and development of the UK National DNA Database (NDNAD) as an instance of the ‘scientification of police work’ (Ericson and Shearing 1986) in which the police uses of science and technology have a recursive effect on their future development. The NDNAD, owned by the Association of Chief Police Officers of England and Wales, is the first of its kind in the world and currently contains the genetic profiles of more than 2 million people. The paper provides a framework for the examination of this socio-technical innovation, begins to tease out the dense and compact history of the database and accounts for the way in which changes and developments across disparate scientific, governmental and policing contexts, have all contributed to the range of uses to which it is put. PMID:16467921

  2. Population genetic data and forensic parameters of 30 autosomal InDel markers in Santa Catarina State population, Southern Brazil.

    PubMed

    Torres, Sandra Regina Rachadel; Uehara, Clineu Julien Seki; Sutter-Latorre, Ana Frederica; de Almeida, Bibiana Sgorla; Sauerbier, Tania Streck; Muniz, Yara Costa Netto; Marrero, Andrea Rita; de Souza, Ilíada Rainha

    2014-08-01

    The application of DNA technology in forensic investigations has grown rapidly in the last 25 years and with an exponential increase of short tandem repeats (STRs) data, usually presented as allele frequencies, that may be later used as databases for forensic and population genetics purposes. Thereby, classes of molecular markers such as single nucleotide polymorphisms and insertions/deletions (InDels) have been presented as another option of genetic marker sets. These markers can be used in paternity cases, when mutations in STR polymorphisms are present, as well as in highly degraded DNA analysis. In the present study, the allele frequencies and heterozygosity (H) of a 30 InDel markers set were determined and the forensic efficacy was evaluated through estimation of discrimination power (DP), match probability, typical paternity index and power of paternity exclusion in 108 unrelated volunteers from the State of Santa Catarina (South Brazil). The observed H per locus showed a range between 0.370 and 0.574 (mean = 0.479). HLD128 was the locus with the highest DP (DP = 0.656). DP for all markers combined was greater than 99.9999999999646 % which provides satisfactory levels of information for forensic demands. Genetic comparisons (exact tests of population differentiation and pairwise genetic distances) revealed that the population of Santa Catarina State differs from Korea and USA Afro-American populations but is similar to the Portuguese, German, Polish, Spanish and Basque populations.

  3. Oral and Craniofacial Clinical Signs Associated to Genetic Conditions in Human Identification Part I: A Review

    PubMed Central

    Ayoub, Fouad; Aoun, Nicole; el Husseini, Hassan; Jassar, Houssam; Sayah, Fida; Salameh, Ziad

    2015-01-01

    Background: Forensic dentistry is one of the most reliable methods used in human identification when other technique as fingerprint, DNA, visual identification cannot be used. Genetic disorders have several manifestations that can target the intra-oral cavity, the cranio-facial area or any location in the human body. Materials and Methods: A literature search of the scientific database (Medline and Science Direct) for the years 1990 to 2014 was carried out to find out all the available papers that indicate oral, cranio-facial signs, genetic and human identification. Results: A table with 10 genetic conditions was described with oral and cranio-facial signs that can help forensic specialist in human identification. Conclusion: This review showed a correlation between genetics, facial and intra-oral signs that would help forensic ondontologist in the identification procedures. PMID:26028912

  4. Next Generation Sequencing Plus (NGS+) with Y-chromosomal Markers for Forensic Pedigree Searches.

    PubMed

    Qian, Xiaoqin; Hou, Jiayi; Wang, Zheng; Ye, Yi; Lang, Min; Gao, Tianzhen; Liu, Jing; Hou, Yiping

    2017-09-12

    There is high demand for forensic pedigree searches with Y-chromosome short tandem repeat (Y-STR) profiling in large-scale crime investigations. However, when two Y-STR haplotypes have a few mismatched loci, it is difficult to determine if they are from the same male lineage because of the high mutation rate of Y-STRs. Here we design a new strategy to handle cases in which none of pedigree samples shares identical Y-STR haplotype. We combine next generation sequencing (NGS), capillary electrophoresis and pyrosequencing under the term 'NGS+' for typing Y-STRs and Y-chromosomal single nucleotide polymorphisms (Y-SNPs). The high-resolution Y-SNP haplogroup and Y-STR haplotype can be obtained with NGS+. We further developed a new data-driven decision rule, FSindex, for estimating the likelihood for each retrieved pedigree. Our approach enables positive identification of pedigree from mismatched Y-STR haplotypes. It is envisaged that NGS+ will revolutionize forensic pedigree searches, especially when the person of interest was not recorded in forensic DNA database.

  5. Forensic science, genetics and wildlife biology: getting the right mix for a wildlife DNA forensics lab.

    PubMed

    Ogden, Rob

    2010-09-01

    Wildlife DNA forensics is receiving increasing coverage in the popular press and has begun to appear in the scientific literature in relation to several different fields. Recognized as an applied subject, it rests on top of very diverse scientific pillars ranging from biochemistry through to evolutionary genetics, all embedded within the context of modern forensic science. This breadth of scope, combined with typically limited resources, has often left wildlife DNA forensics hanging precariously between human DNA forensics and academics keen to seek novel applications for biological research. How best to bridge this gap is a matter for regular debate among the relatively few full-time practitioners in the field. The decisions involved in establishing forensic genetic services to investigate wildlife crime can be complex, particularly where crimes involve a wide range of species and evidential questions. This paper examines some of the issues relevant to setting up a wildlife DNA forensics laboratory based on experiences of working in this area over the past 7 years. It includes a discussion of various models for operating individual laboratories as well as options for organizing forensic testing at higher national and international levels.

  6. 9649 forensic web watch--DNA in forensic science.

    PubMed

    Bowyer, V L; Graham, E A M; Rutty, G N

    2004-10-01

    In 1923, within the Manual of Police technique, Edmond Locard published what is commonly known as the Doctrine of Exchange; a series of rules related to the exchange of trace evidence between the victim and offender. Although at the time of publication these rules principally applied to trace evidence related to print (for exchange finger print or shoeprint), fibre and blood, today one can add the very substance that defines each human being -- DNA. Since th first use of DNA evidence to help identify an offender in the Pitchfork Murders of 1986, the use of DNA within forensic science has developed from its humble days within a single experimental laboratory at the University of Leicester to a multi-million pound industry. It thus seams fitting that this forensic web watch should originate from the very University where the use of DNA in forensic science was conceived, drawing the readers attention to a number of sites which can be used as an introduction to the concept of the use of DNA in forensic science today.

  7. DNA-based methods of geochemical prospecting

    DOEpatents

    Ashby, Matthew [Mill Valley, CA

    2011-12-06

    The present invention relates to methods for performing surveys of the genetic diversity of a population. The invention also relates to methods for performing genetic analyses of a population. The invention further relates to methods for the creation of databases comprising the survey information and the databases created by these methods. The invention also relates to methods for analyzing the information to correlate the presence of nucleic acid markers with desired parameters in a sample. These methods have application in the fields of geochemical exploration, agriculture, bioremediation, environmental analysis, clinical microbiology, forensic science and medicine.

  8. Forensic aspects of DNA-based human identity testing.

    PubMed

    Roper, Stephen M; Tatum, Owatha L

    2008-01-01

    The forensic applications of DNA-based human identity laboratory testing are often underappreciated. Molecular biology has seen an exponential improvement in the accuracy and statistical power provided by identity testing in the past decade. This technology, dependent upon an individual's unique DNA sequence, has cemented the use of DNA technology in the forensic laboratory. This paper will discuss the state of modern DNA-based identity testing, describe the technology used to perform this testing, and describe its use as it relates to forensic applications. We will also compare individual technologies, including polymerase chain reaction (PCR) and Southern Blotting, that are used to detect the molecular differences that make all individuals unique. An increasing reliance on DNA-based identity testing dictates that healthcare providers develop an understanding of the background, techniques, and guiding principles of this important forensic tool.

  9. [Developing forensic reference database by 18 autosomal STR for DNA identification in Republic of Belarus].

    PubMed

    Tsybovskii, I S; Veremeichik, V M; Kotova, S A; Kritskaya, S V; Evmenenko, S A; Udina, I G

    2017-02-01

    For the Republic of Belarus, development of a forensic reference database on the basis of 18 autosomal microsatellites (STR) using a population dataset (N = 1040), “familial” genotypic dataset (N = 2550) obtained from expertise performance of paternity testing, and a dataset of genotypes from a criminal registration database (N = 8756) is described. Population samples studied consist of 80% ethnic Belarusians and 20% individuals of other nationality or of mixed origin (by questionnaire data). Genotypes of 12346 inhabitants of the Republic of Belarus from 118 regional samples studied by 18 autosomal microsatellites are included in the sample: 16 tetranucleotide STR (D2S1338, TPOX, D3S1358, CSF1PO, D5S818, D8S1179, D7S820, THO1, vWA, D13S317, D16S539, D18S51, D19S433, D21S11, F13B, and FGA) and two pentanucleotide STR (Penta D and Penta E). The samples studied are in Hardy–Weinberg equilibrium according to distribution of genotypes by 18 STR. Significant differences were not detected between discrete populations or between samples from various historical ethnographic regions of the Republic of Belarus (Western and Eastern Polesie, Podneprovye, Ponemanye, Poozerye, and Center), which indicates the absence of prominent genetic differentiation. Statistically significant differences between the studied genotypic datasets also were not detected, which made it possible to combine the datasets and consider the total sample as a unified forensic reference database for 18 “criminalistic” STR loci. Differences between reference database of the Republic of Belarus and Russians and Ukrainians by the distribution of the range of autosomal STR also were not detected, corresponding to a close genetic relationship of the three Eastern Slavic nations mediated by common origin and intense mutual migrations. Significant differences by separate STR loci between the reference database of Republic of Belarus and populations of Southern and Western Slavs were observed. The necessity of using original reference database for support of forensic expertise practice in the Republic of Belarus was demonstrated.

  10. Canis mtDNA HV1 database: a web-based tool for collecting and surveying Canis mtDNA HV1 haplotype in public database.

    PubMed

    Thai, Quan Ke; Chung, Dung Anh; Tran, Hoang-Dung

    2017-06-26

    Canine and wolf mitochondrial DNA haplotypes, which can be used for forensic or phylogenetic analyses, have been defined in various schemes depending on the region analyzed. In recent studies, the 582 bp fragment of the HV1 region is most commonly used. 317 different canine HV1 haplotypes have been reported in the rapidly growing public database GenBank. These reported haplotypes contain several inconsistencies in their haplotype information. To overcome this issue, we have developed a Canis mtDNA HV1 database. This database collects data on the HV1 582 bp region in dog mitochondrial DNA from the GenBank to screen and correct the inconsistencies. It also supports users in detection of new novel mutation profiles and assignment of new haplotypes. The Canis mtDNA HV1 database (CHD) contains 5567 nucleotide entries originating from 15 subspecies in the species Canis lupus. Of these entries, 3646 were haplotypes and grouped into 804 distinct sequences. 319 sequences were recognized as previously assigned haplotypes, while the remaining 485 sequences had new mutation profiles and were marked as new haplotype candidates awaiting further analysis for haplotype assignment. Of the 3646 nucleotide entries, only 414 were annotated with correct haplotype information, while 3232 had insufficient or lacked haplotype information and were corrected or modified before storing in the CHD. The CHD can be accessed at http://chd.vnbiology.com . It provides sequences, haplotype information, and a web-based tool for mtDNA HV1 haplotyping. The CHD is updated monthly and supplies all data for download. The Canis mtDNA HV1 database contains information about canine mitochondrial DNA HV1 sequences with reconciled annotation. It serves as a tool for detection of inconsistencies in GenBank and helps identifying new HV1 haplotypes. Thus, it supports the scientific community in naming new HV1 haplotypes and to reconcile existing annotation of HV1 582 bp sequences.

  11. Virtopsy - the concept of a centralized database in forensic medicine for analysis and comparison of radiological and autopsy data.

    PubMed

    Aghayev, Emin; Staub, Lukas; Dirnhofer, Richard; Ambrose, Tony; Jackowski, Christian; Yen, Kathrin; Bolliger, Stephan; Christe, Andreas; Roeder, Christoph; Aebi, Max; Thali, Michael J

    2008-04-01

    Recent developments in clinical radiology have resulted in additional developments in the field of forensic radiology. After implementation of cross-sectional radiology and optical surface documentation in forensic medicine, difficulties in the validation and analysis of the acquired data was experienced. To address this problem and for the comparison of autopsy and radiological data a centralized database with internet technology for forensic cases was created. The main goals of the database are (1) creation of a digital and standardized documentation tool for forensic-radiological and pathological findings; (2) establishing a basis for validation of forensic cross-sectional radiology as a non-invasive examination method in forensic medicine that means comparing and evaluating the radiological and autopsy data and analyzing the accuracy of such data; and (3) providing a conduit for continuing research and education in forensic medicine. Considering the infrequent availability of CT or MRI for forensic institutions and the heterogeneous nature of case material in forensic medicine an evaluation of benefits and limitations of cross-sectional imaging concerning certain forensic features by a single institution may be of limited value. A centralized database permitting international forensic and cross disciplinary collaborations may provide important support for forensic-radiological casework and research.

  12. Air Land Sea Bulletin. Issue No. 2013-1

    DTIC Science & Technology

    2013-01-01

    face, finger- print, iris , DNA, and palm print. Biometric capabilities may achieve enabling effects such as the ability to separate, identify...to obtain forensic-quality fingerprints, latent fingerprints, iris images, photos, and other biometric data. Figure 1. SEEK II ALSB 2013-1 12...logical and biographical contextual data of POIs and matches fingerprints and iris images against an internal biomet- rics enrollment database. The

  13. Amelogenin test: From forensics to quality control in clinical and biochemical genomics.

    PubMed

    Francès, F; Portolés, O; González, J I; Coltell, O; Verdú, F; Castelló, A; Corella, D

    2007-01-01

    The increasing number of samples from the biomedical genetic studies and the number of centers participating in the same involves increasing risk of mistakes in the different sample handling stages. We have evaluated the usefulness of the amelogenin test for quality control in sample identification. Amelogenin test (frequently used in forensics) was undertaken on 1224 individuals participating in a biomedical study. Concordance between referred sex in the database and amelogenin test was estimated. Additional sex-error genetic detecting systems were developed. The overall concordance rate was 99.84% (1222/1224). Two samples showed a female amelogenin test outcome, being codified as males in the database. The first, after checking sex-specific biochemical and clinical profile data was found to be due to a codification error in the database. In the second, after checking the database, no apparent error was discovered because a correct male profile was found. False negatives in amelogenin male sex determination were discarded by additional tests, and feminine sex was confirmed. A sample labeling error was revealed after a new DNA extraction. The amelogenin test is a useful quality control tool for detecting sex-identification errors in large genomic studies, and can contribute to increase its validity.

  14. Current and future directions of DNA in wildlife forensic science.

    PubMed

    Johnson, Rebecca N; Wilson-Wilde, Linzi; Linacre, Adrian

    2014-05-01

    Wildlife forensic science may not have attained the profile of human identification, yet the scale of criminal activity related to wildlife is extensive by any measure. Service delivery in the arena of wildlife forensic science is often ad hoc, unco-ordinated and unregulated, yet many of those currently dedicated to wildlife conservation and the protection of endangered species are striving to ensure that the highest standards are met. The genetic markers and software used to evaluate data in wildlife forensic science are more varied than those in human forensic identification and are rarely standardised between species. The time and resources required to characterise and validate each genetic maker is considerable and in some cases prohibitive. Further, issues are regularly encountered in the construction of allelic databases and allelic ladders; essential in human identification studies, but also applicable to wildlife criminal investigations. Accreditation and certification are essential in human identification and are currently being strived for in the forensic wildlife community. Examples are provided as to how best practice can be demonstrated in all areas of wildlife crime analysis and ensure that this field of forensic science gains and maintains the respect it deserves. This review is aimed at those conducting human identification to illustrate how research concepts in wildlife forensic science can be used in the criminal justice system, as well as describing the real importance of this type of forensic analysis. Crown Copyright © 2013. Published by Elsevier Ireland Ltd. All rights reserved.

  15. Forensically Relevant Blow Flies in Lebanon Survey and Identification Using Molecular Markers (Diptera: Calliphoridae).

    PubMed

    Shayya, Salman; Debruyne, Régis; Nel, André; Azar, Dany

    2018-05-12

    Calliphoridae are among the first insects associated to decomposing animal remains. We have collected 1,841 specimens of three calliphorid genera: Calliphora, Lucilia, and Chrysomya, from different Lebanese localities as a first step in implementing a database of insects of forensic relevance for the country. Blow-flies are crucial for the estimation of the postmortem interval. DNA-based identification is a rapid and accurate method, often used for morphologically similar species, especially for immatures or incomplete specimens. In this study, we test the suitability of three genetic markers to identify adults and immature stages of calliphorids, viz., mitochondrial cytochrome c oxidase subunit I (COI) barcode, a region including partial sequences of mitochondrial Cyt-b-tRNAser-ND1, and second internal transcribed spacer (ITS2) region of nuclear ribosomal DNA. Forty Lebanese specimens of various developmental stages (egg, larva, wandering third instar, pupa, newly emerged adult, and mature adult) were identified among the three calliphorid genera: Calliphora, Lucilia, and Chrysomya, and compared with published sequences to confirm their specific assignation. Phylogenetic analyses showed the robustness of ITS2 and COI to identify calliphorids at species level. Nevertheless, ITS2 failed to discriminate Lucilia caesar (Linnaeus) (Diptera, Calliphoridae) from Lucilia illustris (Meigen) (Diptera, Calliphoridae), and COI had a similar issue with Lucilia sericata (Meigen) (Diptera, Calliphoridae) and Lucilia cuprina (Wiedemann) (Diptera, Calliphoridae). Thus, these two markers are complementary. This work contributes new nucleotide sequences for Lebanon. It is a first step in implementing a molecular database of forensic relevant insects for the country.

  16. Logical Framework of Forensic Identification: Ability to Resist Fabricated DNA.

    PubMed

    Wang, Zheng; Zhou, Di; Zhang, Suhua; Bian, Yingnan; Hu, Zhen; Zhu, Ruxin; Lu, Daru; Li, Chengtao

    2015-12-01

    Over the past 30 years, DNA analysis has revolutionized forensic science and has become the most useful single tool in the multifaceted fight against crime. Today, DNA profiling with sets of highly polymorphic autosomal short tandem repeat markers is widely employed and accepted in the courts due to its high discriminating power and reliability. However, an artificial bloodstain purposefully created using molecular biology techniques succeeded in tricking a leading forensic DNA laboratory. The disturbing possibility that a forensic DNA profile can be faked shocked the general public and the mass media, and generated serious discussion about the credibility of DNA evidence. Herein, we present two exemplary assays based on tissue-specific methylation patterns and cell-specific mRNA expression, respectively. These two assays can be integrated into the DNA analysis pipelines without consumption of additional samples. We show that the two assays can not only distinguish between artificial and genuine samples, but also provide information on tissue origin. The two assays were tested on natural and artificial bloodstains (generated by polymerase chain reaction and whole genome amplification technique) and the results illustrated that the logical framework of forensic identification is still useful for forensic identification with the high credibility.

  17. Forensic DNA Phenotyping: Predicting human appearance from crime scene material for investigative purposes.

    PubMed

    Kayser, Manfred

    2015-09-01

    Forensic DNA Phenotyping refers to the prediction of appearance traits of unknown sample donors, or unknown deceased (missing) persons, directly from biological materials found at the scene. "Biological witness" outcomes of Forensic DNA Phenotyping can provide investigative leads to trace unknown persons, who are unidentifiable with current comparative DNA profiling. This intelligence application of DNA marks a substantially different forensic use of genetic material rather than that of current DNA profiling presented in the courtroom. Currently, group-specific pigmentation traits are already predictable from DNA with reasonably high accuracies, while several other externally visible characteristics are under genetic investigation. Until individual-specific appearance becomes accurately predictable from DNA, conventional DNA profiling needs to be performed subsequent to appearance DNA prediction. Notably, and where Forensic DNA Phenotyping shows great promise, this is on a (much) smaller group of potential suspects, who match the appearance characteristics DNA-predicted from the crime scene stain or from the deceased person's remains. Provided sufficient funding being made available, future research to better understand the genetic basis of human appearance will expectedly lead to a substantially more detailed description of an unknown person's appearance from DNA, delivering increased value for police investigations in criminal and missing person cases involving unknowns. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Minors or suspects? A discussion of the legal and ethical issues surrounding the indefinite storage of DNA collected from children aged 10-18 years on the National DNA Database in England and Wales.

    PubMed

    Mansel, Charlotte; Davies, Sharon

    2012-10-01

    There are currently over 250,000 children between the ages of 10 and 18 years who have their genetic information stored on the National DNA Database. This paper explores the legal and ethical issues surrounding this controversial subject, with particular focus on juvenile capacity and the potential results of criminalizing young children and adolescents. The implications of the adverse legal judgement of the European Court of Human Rights in S and Marper v UK (2008) and the violation of Article 8 of the Convention are discussed. The authors have considered the requirement to balance the rights of the individual, particularly those of minors, against the need to protect the public and have compared the position in Scotland to that of the rest of the UK. The authors conclude that a more ethically acceptable alternative could be the creation of a separate forensic database for children aged 10-18 years, set up to safeguard the interests of those who have not been convicted of any crime.

  19. Forensic DNA phenotyping in criminal investigations and criminal courts: assessing and mitigating the dilemmas inherent in the science.

    PubMed

    MacLean, Charles E; Lamparello, Adam

    2014-01-01

    Forensic DNA Phenotyping ("FDP"), estimating the externally visible characteristics ("EVCs") of the source of human DNA left at a crime scene, is evolving from science fiction toward science fact. FDP can already identify a source's gender with 100% accuracy, and likely hair color, iris color, adult height, and a number of other EVCs with accuracy rates approaching 70%. Patent applications have been filed for approaches to generating 3D likenesses of DNA sources based on the DNA alone. Nonetheless, criminal investigators, particularly in the United States, have been reticent to apply FDP in their casework. The reticence is likely related to a number of perceived and real dilemmas associated with FDP: is FDP racial profiling, should we test unknown and unseen physical conditions, does testing for behavioral characteristics impermissibly violate the source's privacy, ought testing be permitted for samples from known sources or DNA databases, and should FDP be limited to use in investigations only or is FDP appropriate for use in a criminal court. As this article explains, although those dilemmas are substantive, they are not insurmountable, and can be quite easily managed with appropriate regulation and protocols. As FDP continues to develop, there will be less need for criminal investigators to shy away from FDP. Cold cases, missing persons, and victims in crimes without other evidence will one day soon all be well served by FDP.

  20. Investigator® HDplex (Qiagen) reference population database for forensic use in Argentina.

    PubMed

    Martínez, Gustavo; Borosky, Alicia; Corach, Daniel; Llull, Cintia; Locarno, Laura; Lojo, Mercedes; Marino, Miguel; Miozzo, María Cecilia; Modesti, Nidia; Pacharoni, Carla; Pilili, Juan Pablo; Ramella, María Isabel; Sala, Andrea; Schaller, Cecilia; Vullo, Carlos; Toscanini, Ulises

    2017-01-01

    Currently, autosomal Short Tandem Repeat (STR) markers represent the method of election in forensic human identification. Commercial kits of most common use nowadays -e.g. PowerPlex ® Fusion, Promega Corp.; AmpFlSTR GlobalFiler, Thermofisher scientific; Investigator 24Plex QS,Qiagen-, allow the co-amplification of 23 highly polymorphic STR loci providing a high discrimination power in human identity testing. However, in complex kinship analysis and familial database searches involving distant relationships, additional DNA typing is often required in order to achieve well-founded conclusions. The recently developed kit Investigator ® HDplex (Qiagen) co-amplify twelve autosomal STRs markers (D7S1517, D3S1744, D12S391, D2S1360, D6S474, D4S2366, D8S1132, D5S2500, D18S51, D21S2055, D10S2325, SE33), nine of which are not present in the above mentioned kits, providing a set of efficient supplementary markers for human identification purposes. In this study we genotyped a sample of 980 individuals from urban areas of ten Argentinean provinces using the Investigator ® HDplex kit, aiming to provide forensic estimates for use in forensic casework and parentage testing in Argentina. We report reference allelic frequency databases for each of the provinces studied as well as for the combined samples. No deviation of Hardy-Weinberg equilibrium was observed. A reasonable discrimination capacity and power of exclusion was estimated which allowed predicting an acceptable forensic behavior of this kit, either to be used as the main STR panel for simple cases or as an auxiliary tool in complex cases. Additionally, population comparison tests showed that the studied samples are relatively homogeneous across the country for these STR set. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. The HIrisPlex-S system for eye, hair and skin colour prediction from DNA: Introduction and forensic developmental validation.

    PubMed

    Chaitanya, Lakshmi; Breslin, Krystal; Zuñiga, Sofia; Wirken, Laura; Pośpiech, Ewelina; Kukla-Bartoszek, Magdalena; Sijen, Titia; Knijff, Peter de; Liu, Fan; Branicki, Wojciech; Kayser, Manfred; Walsh, Susan

    2018-07-01

    Forensic DNA Phenotyping (FDP), i.e. the prediction of human externally visible traits from DNA, has become a fast growing subfield within forensic genetics due to the intelligence information it can provide from DNA traces. FDP outcomes can help focus police investigations in search of unknown perpetrators, who are generally unidentifiable with standard DNA profiling. Therefore, we previously developed and forensically validated the IrisPlex DNA test system for eye colour prediction and the HIrisPlex system for combined eye and hair colour prediction from DNA traces. Here we introduce and forensically validate the HIrisPlex-S DNA test system (S for skin) for the simultaneous prediction of eye, hair, and skin colour from trace DNA. This FDP system consists of two SNaPshot-based multiplex assays targeting a total of 41 SNPs via a novel multiplex assay for 17 skin colour predictive SNPs and the previous HIrisPlex assay for 24 eye and hair colour predictive SNPs, 19 of which also contribute to skin colour prediction. The HIrisPlex-S system further comprises three statistical prediction models, the previously developed IrisPlex model for eye colour prediction based on 6 SNPs, the previous HIrisPlex model for hair colour prediction based on 22 SNPs, and the recently introduced HIrisPlex-S model for skin colour prediction based on 36 SNPs. In the forensic developmental validation testing, the novel 17-plex assay performed in full agreement with the Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines, as previously shown for the 24-plex assay. Sensitivity testing of the 17-plex assay revealed complete SNP profiles from as little as 63 pg of input DNA, equalling the previously demonstrated sensitivity threshold of the 24-plex HIrisPlex assay. Testing of simulated forensic casework samples such as blood, semen, saliva stains, of inhibited DNA samples, of low quantity touch (trace) DNA samples, and of artificially degraded DNA samples as well as concordance testing, demonstrated the robustness, efficiency, and forensic suitability of the new 17-plex assay, as previously shown for the 24-plex assay. Finally, we provide an update to the publically available HIrisPlex website https://hirisplex.erasmusmc.nl/, now allowing the estimation of individual probabilities for 3 eye, 4 hair, and 5 skin colour categories from HIrisPlex-S input genotypes. The HIrisPlex-S DNA test represents the first forensically validated tool for skin colour prediction, and reflects the first forensically validated tool for simultaneous eye, hair and skin colour prediction from DNA. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Developmental Validation of the Huaxia Platinum System and application in 3 main ethnic groups of China

    PubMed Central

    Wang, Zheng; Zhou, Di; Jia, Zhenjun; Li, Luyao; Wu, Wei; Li, Chengtao; Hou, Yiping

    2016-01-01

    STRs, scattered throughout the genome with higher mutation rate, are attractive to genetic application like forensic, anthropological and population genetics studies. STR profiling has now been applied in various aspects of human identification in forensic investigations. This work described the developmental validation of a novel and universal assay, the Huaxia Platinum System, which amplifies all markers in the expanded CODIS core loci and the Chinese National Database in one single PCR system. Developmental validation demonstrated that this novel assay is accurate, sensitive, reproducible and robust. No discordant calls were observed between the Huaxia Platinum System and other STR systems. Full genotypes could be achieved even with 250 pg of human DNA. Additionally, 402 unrelated individuals from 3 main ethnic groups of China (Han, Uygur and Tibetan) were genotyped to investigate the effectiveness of this novel assay. The CMP were 2.3094 × 10−27, 4.3791 × 10−28 and 6.9118 × 10−27, respectively, and the CPE were 0.99999999939059, 0.99999999989653 and 0.99999999976386, respectively. Aforementioned results suggested that the Huaxia Platinum System is polymorphic and informative, which provides efficient tool for national DNA database and facilitate international data sharing. PMID:27498550

  3. Forensic botany II, DNA barcode for land plants: Which markers after the international agreement?

    PubMed

    Ferri, G; Corradini, B; Ferrari, F; Santunione, A L; Palazzoli, F; Alu', M

    2015-03-01

    The ambitious idea of using a short piece of DNA for large-scale species identification (DNA barcoding) is already a powerful tool for scientists and the application of this standard technique seems promising in a range of fields including forensic genetics. While DNA barcoding enjoyed a remarkable success for animal identification through cytochrome c oxidase I (COI) analysis, the attempts to identify a single barcode for plants remained a vain hope for a longtime. From the beginning, the Consortium for the Barcode of Life (CBOL) showed a lack of agreement on a core plant barcode, reflecting the diversity of viewpoints. Different research groups advocated various markers with divergent set of criteria until the recent publication by the CBOL-Plant Working Group. After a four-year effort, in 2009 the International Team concluded to agree on standard markers promoting a multilocus solution (rbcL and matK), with 70-75% of discrimination to the species level. In 2009 our group firstly proposed the broad application of DNA barcoding principles as a tool for identification of trace botanical evidence through the analysis of two chloroplast loci (trnH-psbA and trnL-trnF) in plant species belonging to local flora. Difficulties and drawbacks that were encountered included a poor coverage of species in specific databases and the lack of authenticated reference sequences for the selected markers. Successful preliminary results were obtained providing an approach to progressively identify unknown plant specimens to a given taxonomic rank, usable by any non-specialist botanist or in case of a shortage of taxonomic expertise. Now we considered mandatory to update and to compare our previous findings with the new selected plastid markers (matK+rbcL), taking into account forensic requirements. Features of all the four loci (the two previously analyzed trnH-psbA+trnL-trnF and matK+rbcL) were compared singly and in multilocus solutions to assess the most suitable combination for forensic botany. Based on obtained results, we recommend the adoption of a two-locus combination with rbcL+trnH-psbA plastid markers, which currently best satisfies forensic needs for botanical species identification. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. Pet fur or fake fur? A forensic approach

    PubMed Central

    2014-01-01

    Background In forensic science there are many types of crime that involve animals. Therefore, the identification of the species has become an essential investigative tool. The exhibits obtained from such offences are very often a challenge for forensic experts. Indeed, most biological materials are traces, hair or tanned fur. With hair samples, a common forensic approach should proceed from morphological and structural microscopic examination to DNA analysis. However, the microscopy of hair requires a lot of experience and a suitable comparative database to be able to recognize with a high degree of accuracy that a sample comes from a particular species and then to determine whether it is a protected one. DNA analysis offers the best opportunity to answer the question, ‘What species is this?’ In our work, we analyzed different samples of fur coming from China used to make hats and collars. Initially, the samples were examined under a microscope, then the mitochondrial DNA was tested for species identification. For this purpose, the genetic markers used were the 12S and 16S ribosomal RNA, while the hypervariable segment I of the control region was analyzed afterwards, to determine whether samples belonged to the same individual. Results Microscopic examination showed that the fibres were of animal origin, although it was difficult to determine with a high degree of confidence which species they belonged to and if they came from a protected species. Therefore, DNA analysis was essential to try to clarify the species of these fur samples. Conclusions Macroscopic and microscopic analysis confirmed the hypothesis regarding the analyzed hair belonging to real animals, although it failed to prove with any kind of certainty which actual family it came from, therefore, the species remains unknown. Sequence data analysis and comparisons with the samples available in GenBank showed that the hair, in most cases, belonged to the Canidae family, and in one case only to Felidae. PMID:24991403

  5. Optimization and validation of a fully automated silica-coated magnetic beads purification technology in forensics.

    PubMed

    Nagy, M; Otremba, P; Krüger, C; Bergner-Greiner, S; Anders, P; Henske, B; Prinz, M; Roewer, L

    2005-08-11

    Automated procedures for forensic DNA analyses are essential not only for large-throughput sample preparation, but are also needed to avoid errors during routine sample preparation. The most critical stage in PCR-based forensic analysis is DNA isolation, which should yield as much highly purified DNA as possible. The extraction method used consists of pre-treatment of stains and samples, cell lysis using chaotropic reagents, binding of the DNA to silica-coated magnetic particles, followed by elution of the DNA. Our work focuses mainly on sample preparation, obtaining the maximum possible amount of biological material from forensic samples, and the following cell lysis, to create a simple standardized lysis protocol suitable for nearly all forensic material. After optimization and validation, the M-48 BioRobot((R)) workstation has been used for more than 20,000 routine lab samples. There has been no evidence of cross contamination. Resulting DNA from as small as three nuclear cells yield reliable complete STR amplification profiles. The DNA remains stable after 2 years of storage.

  6. [The joint applications of DNA chips and single nucleotide polymorphisms in forensic science].

    PubMed

    Bai, Peng; Tian, Li; Zhou, Xue-ping

    2005-05-01

    DNA chip technology, being a new high-technology, shows its vigorous life and rapid growth. Single Nucleotide Polymorphisms (SNPs) is the most common diversity in the human genome. It provides suitable genetic markers which play a key role in disease linkage study, pharmacogenomics, forensic medicine, population evolution and immigration study. Their advantage such as being analyzed with DNA chips technology, is predicted to play an important role in the field of forensic medicine, especially in paternity test and individual identification. This report mainly reviews the characteristics of DNA chip and SNPs, and their joint applications in the practice of forensic medicine.

  7. Y chromosome STR typing in crime casework.

    PubMed

    Roewer, Lutz

    2009-01-01

    Since the beginning of the nineties the field of forensic Y chromosome analysis has been successfully developed to become commonplace in laboratories working in crime casework all over the world. The ability to identify male-specific DNA renders highly variable Y-chromosomal polymorphisms, the STR sequences, an invaluable addition to the standard panel of autosomal loci used in forensic genetics. The male-specificity makes the Y chromosome especially useful in cases of male/female cell admixture, namely in sexual assault cases. On the other hand, the haploidy and patrilineal inheritance complicates the interpretation of a Y-STR match, because male relatives share for several generations an identical Y-STR profile. Since paternal relatives tend to live in the geographic and cultural territory of their ancestors, the Y chromosome analysis has a potential to make inferences on the population of origin of a given DNA profile. This review addresses the fields of application of Y chromosome haplotyping, the interpretation of results, databasing efforts and population genetics aspects.

  8. HOMED-homicides eastern Denmark: an introduction to a forensic medical homicide database.

    PubMed

    Colville-Ebeling, Bonnie; Frisch, Morten; Lynnerup, Niels; Theilade, Peter

    2014-11-01

    An introduction to a forensic medical homicide database established at the Department of Forensic Medicine in Copenhagen. The database contains substantial clinical and demographic data obtained in conjunction with medico-legal autopsies of victims and forensic clinical examinations of perpetrators in homicide cases in eastern Denmark. The database contains information on all homicide cases investigated at the Department of Forensic Medicine in Copenhagen since 1971. Coverage for the catchment area of the department is assumed to be very good because of a medico-legal homicide autopsy rate close to 100%. Regional differences might exist however, due to the fact that the catchment area of the department is dominated by the city of Copenhagen. The strength of the database includes a long running time, near complete regional coverage and an exhaustive list of registered variables it is useful for research purposes, although specific data limitations apply. © 2014 the Nordic Societies of Public Health.

  9. The nucleic acid revolution continues - will forensic biology become forensic molecular biology?

    PubMed

    Gunn, Peter; Walsh, Simon; Roux, Claude

    2014-01-01

    Molecular biology has evolved far beyond that which could have been predicted at the time DNA identity testing was established. Indeed we should now perhaps be referring to "forensic molecular biology." Aside from DNA's established role in identifying the "who" in crime investigations, other developments in medical and developmental molecular biology are now ripe for application to forensic challenges. The impact of DNA methylation and other post-fertilization DNA modifications, plus the emerging role of small RNAs in the control of gene expression, is re-writing our understanding of human biology. It is apparent that these emerging technologies will expand forensic molecular biology to allow for inferences about "when" a crime took place and "what" took place. However, just as the introduction of DNA identity testing engendered many challenges, so the expansion of molecular biology into these domains will raise again the issues of scientific validity, interpretation, probative value, and infringement of personal liberties. This Commentary ponders some of these emerging issues, and presents some ideas on how they will affect the conduct of forensic molecular biology in the foreseeable future.

  10. [Applications of DNA identification technology in protection of wild animals].

    PubMed

    Ni, Ping-Ya; Pei, Li; Ge, Wen-Dong; Zhang, Ying; Yang, Xue-Ying; Xu, Xiao-Yu; Tu, Zheng

    2011-12-01

    With the development of biotechnology, forensic DNA identification technology in protection of wild animals has been used more and more widely. This review introduces the global status of wildlife crime and the relevant protection to wildlife, outlines the practical applications of forensic DNA identification technology with regard to species identification, determination of geographic origin, individual identification and paternity identification. It focus on the techniques commonly used in DNA typing and their merits and demerits, as well as the problems and prospects of forensic DNA technology for wildlife conservation.

  11. Microbial Degradation of Forensic Samples of Biological Origin: Potential Threat to Human DNA Typing.

    PubMed

    Dash, Hirak Ranjan; Das, Surajit

    2018-02-01

    Forensic biology is a sub-discipline of biological science with an amalgam of other branches of science used in the criminal justice system. Any nucleated cell/tissue harbouring DNA, either live or dead, can be used as forensic exhibits, a source of investigation through DNA typing. These biological materials of human origin are rich source of proteins, carbohydrates, lipids, trace elements as well as water and, thus, provide a virtuous milieu for the growth of microbes. The obstinate microbial growth augments the degradation process and is amplified with the passage of time and improper storage of the biological materials. Degradation of these biological materials carriages a huge challenge in the downstream processes of forensic DNA typing technique, such as short tandem repeats (STR) DNA typing. Microbial degradation yields improper or no PCR amplification, heterozygous peak imbalance, DNA contamination from non-human sources, degradation of DNA by microbial by-products, etc. Consequently, the most precise STR DNA typing technique is nullified and definite opinion can be hardly given with degraded forensic exhibits. Thus, suitable precautionary measures should be taken for proper storage and processing of the biological exhibits to minimize their decaying process by micro-organisms.

  12. DNA Fingerprinting in a Forensic Teaching Experiment

    ERIC Educational Resources Information Center

    Wagoner, Stacy A.; Carlson, Kimberly A.

    2008-01-01

    This article presents an experiment designed to provide students, in a classroom laboratory setting, a hands-on demonstration of the steps used in DNA forensic analysis by performing DNA extraction, DNA fingerprinting, and statistical analysis of the data. This experiment demonstrates how DNA fingerprinting is performed and how long it takes. It…

  13. 17 to 23: A novel complementary mini Y-STR panel to extend the Y-STR databases from 17 to 23 markers for forensic purposes.

    PubMed

    Núñez, Carolina; Baeta, Miriam; Ibarbia, Nerea; Ortueta, Urko; Jiménez-Moreno, Susana; Blazquez-Caeiro, José Luis; Builes, Juan José; Herrera, Rene J; Martínez-Jarreta, Begoña; de Pancorbo, Marian M

    2017-04-01

    A Y-STR multiplex system has been developed with the purpose of complementing the widely used 17 Y-STR haplotyping (AmpFlSTR Y Filer® PCR Amplification kit) routinely employed in forensic and population genetic studies. This new multiplex system includes six additional STR loci (DYS576, DYS481, DYS549, DYS533, DYS570, and DYS643) to reach the 23 Y-STR of the PowerPlex® Y23 System. In addition, this kit includes the DYS456 and DYS385 loci for traceability purposes. Male samples from 625 individuals from ten worldwide populations were genotyped, including three sample sets from populations previously published with the 17 Y-STR system to expand their current data. Validation studies demonstrated good performance of the panel set in terms of concordance, sensitivity, and stability in the presence of inhibitors and artificially degraded DNA. The results obtained for haplotype diversity and discrimination capacity with this multiplex system were considerably high, providing further evidences of the suitability of this novel Y-STR system for forensic purposes. Thus, the use of this multiplex for samples previously genotyped with 17 Y-STRs will be an efficient and low-cost alternative to complete the set of 23 Y-STRs and improve allele databases for population and forensic purposes. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Investigating the Epigenetic Discrimination of Identical Twins Using Buccal Swabs, Saliva, and Cigarette Butts in the Forensic Setting.

    PubMed

    Vidaki, Athina; Kalamara, Vivian; Carnero-Montoro, Elena; Spector, Timothy D; Bell, Jordana T; Kayser, Manfred

    2018-05-14

    Monozygotic (MZ) twins are typically indistinguishable via forensic DNA profiling. Recently, we demonstrated that epigenetic differentiation of MZ twins is feasible; however, proportions of twin differentially methylated CpG sites (tDMSs) identified in reference-type blood DNA were not replicated in trace-type blood DNA. Here we investigated buccal swabs as typical forensic reference material, and saliva and cigarette butts as commonly encountered forensic trace materials. As an analog to a forensic case, we analyzed one MZ twin pair. Epigenome-wide microarray analysis in reference-type buccal DNA revealed 25 candidate tDMSs with >0.5 twin-to-twin differences. MethyLight quantitative PCR (qPCR) of 22 selected tDMSs in trace-type DNA revealed in saliva DNA that six tDMSs (27.3%) had >0.1 twin-to-twin differences, seven (31.8%) had smaller (<0.1) but robustly detected differences, whereas for nine (40.9%) the differences were in the opposite direction relative to the microarray data; for cigarette butt DNA, results were 50%, 22.7%, and 27.3%, respectively. The discrepancies between reference-type and trace-type DNA outcomes can be explained by cell composition differences, method-to-method variation, and other technical reasons including bisulfite conversion inefficiency. Our study highlights the importance of the DNA source and that careful characterization of biological and technical effects is needed before epigenetic MZ twin differentiation is applicable in forensic casework.

  15. Forensic DNA methylation profiling from minimal traces: How low can we go?

    PubMed

    Naue, Jana; Hoefsloot, Huub C J; Kloosterman, Ate D; Verschure, Pernette J

    2018-03-01

    Analysis of human DNA methylation (DNAm) can provide additional investigative leads in crime cases, e.g. the type of tissue or body fluid, the chronological age of an individual, and differentiation between identical twins. In contrast to the genetic profile, the DNAm level is not the same in every cell. At the single cell level, DNAm represents a binary event at a defined CpG site (methylated versus non-methylated). The DNAm level from a DNA extract however represents the average level of methylation of the CpG of interest of all molecules in the forensic sample. The variance of DNAm levels between replicates is often attributed to technological issues, i.e. degradation of DNA due to bisulfite treatment, preferential amplification of DNA, and amplification failure. On the other hand, we show that stochastic variations can lead to gross fluctuation in the analysis of methylation levels in samples with low DNA levels. This stochasticity in DNAm results is relevant since low DNA amounts (1pg - 1ng) is rather the norm than the exception when analyzing forensic DNA samples. This study describes a conceptual analysis of DNAm profiling and its dependence on the amount of input DNA. We took a close look at the variation of DNAm analysis due to DNA input and its consequences for different DNAm-based forensic applications. As can be expected, the 95%-confidence interval of measured DNAm becomes narrower with increasing amounts of DNA. We compared this aspect for two different DNAm-based forensic applications: body fluid identification and chronological age determination. Our study shows that DNA amount should be well considered when using DNAm for forensic applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Statistical and population genetics issues of two Hungarian datasets from the aspect of DNA evidence interpretation.

    PubMed

    Szabolcsi, Zoltán; Farkas, Zsuzsa; Borbély, Andrea; Bárány, Gusztáv; Varga, Dániel; Heinrich, Attila; Völgyi, Antónia; Pamjav, Horolma

    2015-11-01

    When the DNA profile from a crime-scene matches that of a suspect, the weight of DNA evidence depends on the unbiased estimation of the match probability of the profiles. For this reason, it is required to establish and expand the databases that reflect the actual allele frequencies in the population applied. 21,473 complete DNA profiles from Databank samples were used to establish the allele frequency database to represent the population of Hungarian suspects. We used fifteen STR loci (PowerPlex ESI16) including five, new ESS loci. The aim was to calculate the statistical, forensic efficiency parameters for the Databank samples and compare the newly detected data to the earlier report. The population substructure caused by relatedness may influence the frequency of profiles estimated. As our Databank profiles were considered non-random samples, possible relationships between the suspects can be assumed. Therefore, population inbreeding effect was estimated using the FIS calculation. The overall inbreeding parameter was found to be 0.0106. Furthermore, we tested the impact of the two allele frequency datasets on 101 randomly chosen STR profiles, including full and partial profiles. The 95% confidence interval estimates for the profile frequencies (pM) resulted in a tighter range when we used the new dataset compared to the previously published ones. We found that the FIS had less effect on frequency values in the 21,473 samples than the application of minimum allele frequency. No genetic substructure was detected by STRUCTURE analysis. Due to the low level of inbreeding effect and the high number of samples, the new dataset provides unbiased and precise estimates of LR for statistical interpretation of forensic casework and allows us to use lower allele frequencies. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. How convincing is a matching Y-chromosome profile?

    PubMed Central

    2017-01-01

    The introduction of forensic autosomal DNA profiles was controversial, but the problems were successfully addressed, and DNA profiling has gone on to revolutionise forensic science. Y-chromosome profiles are valuable when there is a mixture of male-source and female-source DNA, and interest centres on the identity of the male source(s) of the DNA. The problem of evaluating evidential weight is even more challenging for Y profiles than for autosomal profiles. Numerous approaches have been proposed, but they fail to deal adequately with the fact that men with matching Y-profiles are related in extended patrilineal clans, many of which may not be represented in available databases. The higher mutation rates of modern profiling kits have led to increased discriminatory power but they have also exacerbated the problem of fairly conveying evidential value. Because the relevant population is difficult to define, yet the number of matching relatives is fixed as population size varies, it is typically infeasible to derive population-based match probabilities relevant to a specific crime. We propose a conceptually simple solution, based on a simulation model and software to approximate the distribution of the number of males with a matching Y profile. We show that this distribution is robust to different values for the variance in reproductive success and the population growth rate. We also use importance sampling reweighting to derive the distribution of the number of matching males conditional on a database frequency, finding that this conditioning typically has only a modest impact. We illustrate the use of our approach to quantify the value of Y profile evidence for a court in a way that is both scientifically valid and easily comprehensible by a judge or juror. PMID:29099833

  18. Strengthening forensic DNA decision making through a better understanding of the influence of cognitive bias.

    PubMed

    Jeanguenat, Amy M; Budowle, Bruce; Dror, Itiel E

    2017-11-01

    Cognitive bias may influence process flows and decision making steps in forensic DNA analyses and interpretation. Currently, seven sources of bias have been identified that may affect forensic decision making with roots in human nature; environment, culture, and experience; and case specific information. Most of the literature and research on cognitive bias in forensic science has focused on patterned evidence; however, forensic DNA testing is not immune to bias, especially when subjective interpretation is involved. DNA testing can be strengthened by recognizing the existence of bias, evaluating where it influences decision making, and, when applicable, implementing practices to reduce or control its effects. Elements that may improve forensic decision making regarding bias include cognitively informed education and training, quality assurance procedures, review processes, analysis and interpretation, and context management of irrelevant information. Although bias exists, reliable results often can be (and have been) produced. However, at times bias can (and has) impacted the interpretation of DNA results negatively. Therefore, being aware of the dangers of bias and implementing measures to control its potential impact should be considered. Measures and procedures that handicap the workings of the crime laboratory or add little value to improving the operation are not advocated, but simple yet effective measures are suggested. This article is meant to raise awareness of cognitive bias contamination in forensic DNA testing and to give laboratories possible pathways to make sound decisions to address its influences. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.

  19. Comprehensive annotated STR physical map of the human Y chromosome: Forensic implications.

    PubMed

    Hanson, Erin K; Ballantyne, Jack

    2006-03-01

    A plethora of Y-STR markers from diverse sources have been deposited in public databases and represent potential candidates for incorporation into the next generation of Y-STR multiplexes for forensic use. Here, based upon all of the Y-STR loci that have been deposited in the human genome database (>400), we have sequentially positioned each one along the Y chromosome using the most current human genome sequencing data (NCBI Build 35). The information derived from this work defines the number and relative position of all potentially forensically relevant Y-STR loci, their location within the physical linkage map of the Y chromosome and their relationship to structural genes. We conclude that there exists at present at least 417 separate Y-STR markers available for potential forensic use, although many of these will be found to be unsuitable for other reasons. However, from this data, we were able to identify 28 pairs of duplicated loci that were given separate DYS designations and four pairs of loci with overlapping flanking regions. Removing one locus from each set of duplicates reduced the number of potentially useful loci from 417 to 389. The derived information should be useful for workers who are designing novel Y-STR multiplexes to ensure the presence of non-synonymous loci and, if so desired, to avoid loci that lie within structural genes. It may also be useful for forensic casework practitioners (or molecular anthropologists) to aid in distinguishing between chromosomal rearrangements (such as duplications and deletions) and bona fide DNA admixtures or null alleles caused by primer binding site mutations. We illustrate the practical usefulness of the chromosomal positioning data in the design of eight multiplex systems using 94 Y-STR loci.

  20. Post-conviction DNA testing: the UK's first ‘exoneration’ case?

    PubMed Central

    Johnson, Paul; Williams, Robin

    2005-01-01

    The routine incorporation of forensic DNA profiling into the criminal justice systems of the United Kingdom has been widely promoted as a device for improving the quality of investigative and prosecutorial processes. From its first uses in the 1980s, in cases of serious crime, to the now daily collection, analysis and comparison of genetic samples in the National DNA Database, DNA profiling has become a standard instrument of policing and a powerful evidential resource for prosecutors. However, the use of post-conviction DNA testing has, until recently, been uncommon in the United Kingdom. This paper explores the first case, in England, of the contribution of DNA profiling to a successful appeal against conviction by an imprisoned offender. Analysis of the details of this case is used to emphasise the ways in which novel forms of scientific evidence remain subject to traditional and heterogeneous tests of relevance and credibility. PMID:15112595

  1. Random whole metagenomic sequencing for forensic discrimination of soils.

    PubMed

    Khodakova, Anastasia S; Smith, Renee J; Burgoyne, Leigh; Abarno, Damien; Linacre, Adrian

    2014-01-01

    Here we assess the ability of random whole metagenomic sequencing approaches to discriminate between similar soils from two geographically distinct urban sites for application in forensic science. Repeat samples from two parklands in residential areas separated by approximately 3 km were collected and the DNA was extracted. Shotgun, whole genome amplification (WGA) and single arbitrarily primed DNA amplification (AP-PCR) based sequencing techniques were then used to generate soil metagenomic profiles. Full and subsampled metagenomic datasets were then annotated against M5NR/M5RNA (taxonomic classification) and SEED Subsystems (metabolic classification) databases. Further comparative analyses were performed using a number of statistical tools including: hierarchical agglomerative clustering (CLUSTER); similarity profile analysis (SIMPROF); non-metric multidimensional scaling (NMDS); and canonical analysis of principal coordinates (CAP) at all major levels of taxonomic and metabolic classification. Our data showed that shotgun and WGA-based approaches generated highly similar metagenomic profiles for the soil samples such that the soil samples could not be distinguished accurately. An AP-PCR based approach was shown to be successful at obtaining reproducible site-specific metagenomic DNA profiles, which in turn were employed for successful discrimination of visually similar soil samples collected from two different locations.

  2. Establishing a database of Canadian feline mitotypes for forensic use.

    PubMed

    Arcieri, M; Agostinelli, G; Gray, Z; Spadaro, A; Lyons, L A; Webb, K M

    2016-05-01

    Hair shed by pet animals is often found and collected as evidence from crime scenes. Due to limitations such as small amount and low quality, mitochondrial DNA (mtDNA) is often the only type of DNA that can be used for linking the hair to a potential contributor. mtDNA has lower discriminatory power than nuclear DNA because multiple, unrelated individuals within a population can have the same mtDNA sequence, or mitotype. Therefore, to determine the evidentiary value of a match between crime scene evidence and a suspected contributor, the frequency of the mitotype must be known within the regional population. While mitotype frequencies have been determined for the United States' cat population, the frequencies are unknown for the Canadian cat population. Given the countries' close proximity and similar human settlement patterns, these populations may be homogenous, meaning a single, regional database may be used for estimating cat population mitotype frequencies. Here we determined the mitotype frequencies of the Canadian cat population and compared them to the United States' cat population. The two cat populations are statistically homogenous, however mitotype B6 was found in high frequency in Canada and extremely low frequency in the United States, meaning a single database would not be appropriate for North America. Furthermore, this work calls attention to these local spikes in frequency of otherwise rare mitotypes, instances of which exist around the world and have the potential to misrepresent the evidentiary value of matches compared to a regional database. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. [Research Progress on the Detection Method of DNA Methylation and Its Application in Forensic Science].

    PubMed

    Nie, Y C; Yu, L J; Guan, H; Zhao, Y; Rong, H B; Jiang, B W; Zhang, T

    2017-06-01

    As an important part of epigenetic marker, DNA methylation involves in the gene regulation and attracts a wide spread attention in biological auxology, geratology and oncology fields. In forensic science, because of the relative stable, heritable, abundant, and age-related characteristics, DNA methylation is considered to be a useful complement to the classic genetic markers for age-prediction, tissue-identification, and monozygotic twins' discrimination. Various methods for DNA methylation detection have been validated based on methylation sensitive restriction endonuclease, bisulfite modification and methylation-CpG binding protein. In recent years, it is reported that the third generation sequencing method can be used to detect DNA methylation. This paper aims to make a review on the detection method of DNA methylation and its applications in forensic science. Copyright© by the Editorial Department of Journal of Forensic Medicine.

  4. [Validation of Differential Extraction Kit in forensic sexual assault cases].

    PubMed

    Wu, Dan; Cao, Yu; Xu, Yan; He, Bai-Fang; Bi, Gang; Zhou, Huai-Gu

    2009-12-01

    To evaluate the validity of Differential Extraction Kit in isolating spermatozoa and epithelial cell DNA from mixture samples. Selective lysis of spermatid and epithelial cells combined with paramagnetic particle method were applied to extract the DNA from the mock samples under controlled conditions and forensic case samples, and template DNA were analyzed by STR genotype method. This Differential Extraction Kit is efficient to obtain high quality spermatid and epithelial cell DNA from the mixture samples with different proportion of sperm to epithelial cell. The Differential Extraction Kit can be applied in DNA extraction for mixed stain from forensic sexual assault samples.

  5. Evaluation of massively parallel sequencing for forensic DNA methylation profiling.

    PubMed

    Richards, Rebecca; Patel, Jayshree; Stevenson, Kate; Harbison, SallyAnn

    2018-05-11

    Epigenetics is an emerging area of interest in forensic science. DNA methylation, a type of epigenetic modification, can be applied to chronological age estimation, identical twin differentiation and body fluid identification. However, there is not yet an agreed, established methodology for targeted detection and analysis of DNA methylation markers in forensic research. Recently a massively parallel sequencing-based approach has been suggested. The use of massively parallel sequencing is well established in clinical epigenetics and is emerging as a new technology in the forensic field. This review investigates the potential benefits, limitations and considerations of this technique for the analysis of DNA methylation in a forensic context. The importance of a robust protocol, regardless of the methodology used, that minimises potential sources of bias is highlighted. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  6. Soil DNA metabarcoding and high-throughput sequencing as a forensic tool: considerations, potential limitations and recommendations.

    PubMed

    Young, J M; Austin, J J; Weyrich, L S

    2017-02-01

    Analysis of physical evidence is typically a deciding factor in forensic casework by establishing what transpired at a scene or who was involved. Forensic geoscience is an emerging multi-disciplinary science that can offer significant benefits to forensic investigations. Soil is a powerful, nearly 'ideal' contact trace evidence, as it is highly individualistic, easy to characterise, has a high transfer and retention probability, and is often overlooked in attempts to conceal evidence. However, many real-life cases encounter close proximity soil samples or soils with low inorganic content, which cannot be easily discriminated based on current physical and chemical analysis techniques. The capability to improve forensic soil discrimination, and identify key indicator taxa from soil using the organic fraction is currently lacking. The development of new DNA sequencing technologies offers the ability to generate detailed genetic profiles from soils and enhance current forensic soil analyses. Here, we discuss the use of DNA metabarcoding combined with high-throughput sequencing (HTS) technology to distinguish between soils from different locations in a forensic context. Specifically, we provide recommendations for best practice, outline the potential limitations encountered in a forensic context and describe the future directions required to integrate soil DNA analysis into casework. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. Mitochondrial DNA control region analysis of three ethnic groups in the Republic of Macedonia

    PubMed Central

    Jankova-Ajanovska, Renata; Zimmermann, Bettina; Huber, Gabriela; Röck, Alexander W.; Bodner, Martin; Jakovski, Zlatko; Janeska, Biljana; Duma, Aleksej; Parson, Walther

    2014-01-01

    A total of 444 individuals representing three ethnic groups (Albanians, Turks and Romanies) in the Republic of Macedonia were sequenced in the mitochondrial control region. The mtDNA haplogroup composition differed between the three groups. Our results showed relatively high frequencies of haplogroup H12 in Albanians (8.8%) and less in Turks (3.3%), while haplogroups M5a1 and H7a1a were dominant in Romanies (13.7% and 10.3%, respectively) but rare in the former two. This highlights the importance of regional sampling for forensic mtDNA databasing purposes. These population data will be available on EMPOP under accession numbers EMP00644 (Albanians), EMP00645 (Romanies) and EMP00646 (Turks). PMID:25051224

  8. Collecting, archiving and processing DNA from wildlife samples using FTA® databasing paper

    PubMed Central

    Smith, LM; Burgoyne, LA

    2004-01-01

    Background Methods involving the analysis of nucleic acids have become widespread in the fields of traditional biology and ecology, however the storage and transport of samples collected in the field to the laboratory in such a manner to allow purification of intact nucleic acids can prove problematical. Results FTA® databasing paper is widely used in human forensic analysis for the storage of biological samples and for purification of nucleic acids. The possible uses of FTA® databasing paper in the purification of DNA from samples of wildlife origin were examined, with particular reference to problems expected due to the nature of samples of wildlife origin. The processing of blood and tissue samples, the possibility of excess DNA in blood samples due to nucleated erythrocytes, and the analysis of degraded samples were all examined, as was the question of long term storage of blood samples on FTA® paper. Examples of the end use of the purified DNA are given for all protocols and the rationale behind the processing procedures is also explained to allow the end user to adjust the protocols as required. Conclusions FTA® paper is eminently suitable for collection of, and purification of nucleic acids from, biological samples from a wide range of wildlife species. This technology makes the collection and storage of such samples much simpler. PMID:15072582

  9. Cementum as a source of DNA in challenging forensic cases.

    PubMed

    Mansour, Hussam; Krebs, Oliver; Sperhake, Jan Peter; Augustin, Christa; Koehne, Till; Amling, Michael; Püschel, Klaus

    2018-02-01

    Each forensic case is characterized by its own uniqueness. Deficient forensic cases require additional sources of human identifiers to assure the identity. We report on two different cases illustrating the role of teeth in answering challenging forensic questions. The first case involves identification of an adipocere male found in a car submersed in water for approximately 2 years. The second scenario, which involves paternity DNA testing of an exhumed body, was performed approximately 2.8 years post-mortem. The difficulty in anticipating the degradation of the DNA is one of the main obstacles. DNA profiling of dental tissues, DNA quantification by using real-time PCR (PowerQuant™ System/Promega) and a histological dental examination have been performed to address the encountered impediments of adverse post-mortem changes. Our results demonstrate that despite the adverse environmental conditions, a successful STR profile of DNA isolated from the root of teeth can be generated with respect to tooth type and apportion. We conclude that cementocytes are a fruitful source of DNA. Cementum resists DNA degradation in comparison to other tissues with respect to the intra- and inter-individual variation of histological and anatomical structures. Copyright © 2018 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  10. Rapid quantification and sex determination of forensic evidence materials.

    PubMed

    Andréasson, Hanna; Allen, Marie

    2003-11-01

    DNA quantification of forensic evidence is very valuable for an optimal use of the available biological material. Moreover, sex determination is of great importance as additional information in criminal investigations as well as in identification of missing persons, no suspect cases, and ancient DNA studies. While routine forensic DNA analysis based on short tandem repeat markers includes a marker for sex determination, analysis of samples containing scarce amounts of DNA is often based on mitochondrial DNA, and sex determination is not performed. In order to allow quantification and simultaneous sex determination on minute amounts of DNA, an assay based on real-time PCR analysis of a marker within the human amelogenin gene has been developed. The sex determination is based on melting curve analysis, while an externally standardized kinetic analysis allows quantification of the nuclear DNA copy number in the sample. This real-time DNA quantification assay has proven to be highly sensitive, enabling quantification of single DNA copies. Although certain limitations were apparent, the system is a rapid, cost-effective, and flexible assay for analysis of forensic casework samples.

  11. Mendel Meets CSI: Forensic Genotyping as a Method to Teach Genetics & DNA Science

    ERIC Educational Resources Information Center

    Kurowski, Scotia; Reiss, Rebecca

    2007-01-01

    This article describes a forensic DNA science laboratory exercise for advanced high school and introductory college level biology courses. Students use a commercial genotyping kit and genetic analyzer or gene sequencer to analyze DNA recovered from a fictitious crime scene. DNA profiling and STR genotyping are outlined. DNA extraction, PCR, and…

  12. Separation/extraction, detection, and interpretation of DNA mixtures in forensic science (review).

    PubMed

    Tao, Ruiyang; Wang, Shouyu; Zhang, Jiashuo; Zhang, Jingyi; Yang, Zihao; Sheng, Xiang; Hou, Yiping; Zhang, Suhua; Li, Chengtao

    2018-05-25

    Interpreting mixed DNA samples containing material from multiple contributors has long been considered a major challenge in forensic casework, especially when encountering low-template DNA (LT-DNA) or high-order mixtures that may involve missing alleles (dropout) and unrelated alleles (drop-in), among others. In the last decades, extraordinary progress has been made in the analysis of mixed DNA samples, which has led to increasing attention to this research field. The advent of new methods for the separation and extraction of DNA from mixtures, novel or jointly applied genetic markers for detection and reliable interpretation approaches for estimating the weight of evidence, as well as the powerful massively parallel sequencing (MPS) technology, has greatly extended the range of mixed samples that can be correctly analyzed. Here, we summarized the investigative approaches and progress in the field of forensic DNA mixture analysis, hoping to provide some assistance to forensic practitioners and to promote further development involving this issue.

  13. Forensic Loci Allele Database (FLAD): Automatically generated, permanent identifiers for sequenced forensic alleles.

    PubMed

    Van Neste, Christophe; Van Criekinge, Wim; Deforce, Dieter; Van Nieuwerburgh, Filip

    2016-01-01

    It is difficult to predict if and when massively parallel sequencing of forensic STR loci will replace capillary electrophoresis as the new standard technology in forensic genetics. The main benefits of sequencing are increased multiplexing scales and SNP detection. There is not yet a consensus on how sequenced profiles should be reported. We present the Forensic Loci Allele Database (FLAD) service, made freely available on http://forensic.ugent.be/FLAD/. It offers permanent identifiers for sequenced forensic alleles (STR or SNP) and their microvariants for use in forensic allele nomenclature. Analogous to Genbank, its aim is to provide permanent identifiers for forensically relevant allele sequences. Researchers that are developing forensic sequencing kits or are performing population studies, can register on http://forensic.ugent.be/FLAD/ and add loci and allele sequences with a short and simple application interface (API). Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  14. MtDNA SNP multiplexes for efficient inference of matrilineal genetic ancestry within Oceania.

    PubMed

    Ballantyne, Kaye N; van Oven, Mannis; Ralf, Arwin; Stoneking, Mark; Mitchell, R John; van Oorschot, Roland A H; Kayser, Manfred

    2012-07-01

    Human mitochondrial DNA (mtDNA) is a convenient marker for tracing matrilineal bio-geographic ancestry and is widely applied in forensic, genealogical and anthropological studies. In forensic applications, DNA-based ancestry inference can be useful for finding unknown suspects by concentrating police investigations in cases where autosomal STR profiling was unable to provide a match, or can help provide clues in missing person identification. Although multiplexed mtDNA single nucleotide polymorphism (SNP) assays to infer matrilineal ancestry at a (near) continental level are already available, such tools are lacking for the Oceania region. Here, we have developed a hierarchical system of three SNaPshot multiplexes for genotyping 26 SNPs defining all major mtDNA haplogroups for Oceania (including Australia, Near Oceania and Remote Oceania). With this system, it was possible to conclusively assign 74% of Oceanian individuals to their Oceanian matrilineal ancestry in an established literature database (after correcting for obvious external admixture). Furthermore, in a set of 161 genotyped individuals collected in Australia, Papua New Guinea and Fiji, 87.6% were conclusively assigned an Oceanian matrilineal origin. For the remaining 12.4% of the genotyped samples either a Eurasian origin was detected indicating likely European admixture (1.9%), the identified haplogroups are shared between Oceania and S/SE-Asia (5%), or the SNPs applied did not allow a geographic inference to be assigned (5.6%). Sub-regional assignment within Oceania was possible for 32.9% of the individuals genotyped: 49.5% of Australians were assigned an Australian origin and 13.7% of the Papua New Guineans were assigned a Near Oceanian origin, although none of the Fijians could be assigned a specific Remote Oceanian origin. The low assignment rates of Near and Remote Oceania are explained by recent migrations from Asia via Near Oceania into Remote Oceania. Combining the mtDNA multiplexes for Oceania introduced here with those we developed earlier for all other continental regions, global matrilineal bio-geographic ancestry assignment from DNA is now achievable in a highly efficient way that is also suitable for applications with limited material such as forensic case work. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  15. Extraction of DNA from forensic-type sexual assault specimens using simple, rapid sonication procedures.

    PubMed

    Crouse, C A; Ban, J D; D'Alessio, J K

    1993-10-01

    Sonication procedures for the extraction of DNA from forensic-type semen specimens have been developed, which, when compared to currently utilized sperm DNA extraction techniques, are simple, rapid and result in comparable DNA yields. Sperm DNA extraction by sonication was performed on whole semen, seminal stains, buccal swabs and post-coital specimens. Ultrasound disruption of sperm cells and their ultimate release of cellular DNA has been conducted in the presence of sperm wash buffers followed by organic extraction or Chelex 100 with little or no compromise to DNA quality, quantity or amplifiability. Two advantages of sonication over currently used forensic techniques to extract sperm DNA include 1) sperm DNA extraction that occurs within five minutes of sonication compared with an hour or greater for water bath incubations in classic enzyme digestion DNA extractions and 2) one less preparatory step with the Chelex/sonication protocol and three less steps with the sonication/organic protocol compared with other procedures thus eliminating potential sample-to-sample cross-contamination. Sperm DNA extracted by optimum sonication procedures was used for forensic HLA DQ alpha typing and restriction fragment length polymorphisms analysis without any adverse effects on typing results.

  16. Direct PCR amplification of forensic touch and other challenging DNA samples: A review.

    PubMed

    Cavanaugh, Sarah E; Bathrick, Abigail S

    2018-01-01

    DNA evidence sample processing typically involves DNA extraction, quantification, and STR amplification; however, DNA loss can occur at both the DNA extraction and quantification steps, which is not ideal for forensic evidence containing low levels of DNA. Direct PCR amplification of forensic unknown samples has been suggested as a means to circumvent extraction and quantification, thereby retaining the DNA typically lost during those procedures. Direct PCR amplification is a method in which a sample is added directly to an amplification reaction without being subjected to prior DNA extraction, purification, or quantification. It allows for maximum quantities of DNA to be targeted, minimizes opportunities for error and contamination, and reduces the time and monetary resources required to process samples, although data analysis may take longer as the increased DNA detection sensitivity of direct PCR may lead to more instances of complex mixtures. ISO 17025 accredited laboratories have successfully implemented direct PCR for limited purposes (e.g., high-throughput databanking analysis), and recent studies indicate that direct PCR can be an effective method for processing low-yield evidence samples. Despite its benefits, direct PCR has yet to be widely implemented across laboratories for the processing of evidentiary items. While forensic DNA laboratories are always interested in new methods that will maximize the quantity and quality of genetic information obtained from evidentiary items, there is often a lag between the advent of useful methodologies and their integration into laboratories. Delayed implementation of direct PCR of evidentiary items can be attributed to a variety of factors, including regulatory guidelines that prevent laboratories from omitting the quantification step when processing forensic unknown samples, as is the case in the United States, and, more broadly, a reluctance to validate a technique that is not widely used for evidence samples. The advantages of direct PCR of forensic evidentiary samples justify a re-examination of the factors that have delayed widespread implementation of this method and of the evidence supporting its use. In this review, the current and potential future uses of direct PCR in forensic DNA laboratories are summarized. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Forensic individual age estimation with DNA: From initial approaches to methylation tests.

    PubMed

    Freire-Aradas, A; Phillips, C; Lareu, M V

    2017-07-01

    Individual age estimation is a key factor in forensic science analysis that can provide very useful information applicable to criminal, legal, and anthropological investigations. Forensic age inference was initially based on morphological inspection or radiography and only later began to adopt molecular approaches. However, a lack of accuracy or technical problems hampered the introduction of these DNA-based methodologies in casework analysis. A turning point occurred when the epigenetic signature of DNA methylation was observed to gradually change during an individual´s lifespan. In the last four years, the number of publications reporting DNA methylation age-correlated changes has gradually risen and the forensic community now has a range of age methylation tests applicable to forensic casework. Most forensic age predictor models have been developed based on blood DNA samples, but additional tissues are now also being explored. This review assesses the most widely adopted genes harboring methylation sites, detection technologies, statistical age-predictive analyses, and potential causes of variation in age estimates. Despite the need for further work to improve predictive accuracy and establishing a broader range of tissues for which tests can analyze the most appropriate methylation sites, several forensic age predictors have now been reported that provide consistency in their prediction accuracies (predictive error of ±4 years); this makes them compelling tools with the potential to contribute key information to help guide criminal investigations. Copyright © 2017 Central Police University.

  18. DNA, Drugs, and Detectives: An Interdisciplinary Special Topics Course for Undergraduate Students in Forensic Science

    ERIC Educational Resources Information Center

    Coticone, Sulekha Rao; Van Houten, Lora Bailey

    2015-01-01

    A special topics course combining two relevant and contemporary themes (forensic DNA analysis and illicit drug detection) was developed to stimulate student enthusiasm and enhance understanding of forensic science. Building on the interest of popular television shows such as "CSI" and "Breaking Bad," this course connects…

  19. An integratable microfluidic cartridge for forensic swab samples lysis.

    PubMed

    Yang, Jianing; Brooks, Carla; Estes, Matthew D; Hurth, Cedric M; Zenhausern, Frederic

    2014-01-01

    Fully automated rapid forensic DNA analysis requires integrating several multistep processes onto a single microfluidic platform, including substrate lysis, extraction of DNA from the released lysate solution, multiplexed PCR amplification of STR loci, separation of PCR products by capillary electrophoresis, and analysis for allelic peak calling. Over the past several years, most of the rapid DNA analysis systems developed started with the reference swab sample lysate and involved an off-chip lysis of collected substrates. As a result of advancement in technology and chemistry, addition of a microfluidic module for swab sample lysis has been achieved in a few of the rapid DNA analysis systems. However, recent reports on integrated rapid DNA analysis systems with swab-in and answer-out capability lack any quantitative and qualitative characterization of the swab-in sample lysis module, which is important for downstream forensic sample processing. Maximal collection and subsequent recovery of the biological material from the crime scene is one of the first and critical steps in forensic DNA technology. Herein we present the design, fabrication and characterization of an integratable swab lysis cartridge module and the test results obtained from different types of commonly used forensic swab samples, including buccal, saliva, and blood swab samples, demonstrating the compatibility with different downstream DNA extraction chemistries. This swab lysis cartridge module is easy to operate, compatible with both forensic and microfluidic requirements, and ready to be integrated with our existing automated rapid forensic DNA analysis system. Following the characterization of the swab lysis module, an integrated run from buccal swab sample-in to the microchip CE electropherogram-out was demonstrated on the integrated prototype instrument. Therefore, in this study, we demonstrate that this swab lysis cartridge module is: (1) functionally, comparable with routine benchtop lysis, (2) compatible with various types of swab samples and chemistries, and (3) integratable to achieve a micro total analysis system (μTAS) for rapid DNA analysis. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  20. Massively parallel sequencing of forensic STRs: Considerations of the DNA commission of the International Society for Forensic Genetics (ISFG) on minimal nomenclature requirements.

    PubMed

    Parson, Walther; Ballard, David; Budowle, Bruce; Butler, John M; Gettings, Katherine B; Gill, Peter; Gusmão, Leonor; Hares, Douglas R; Irwin, Jodi A; King, Jonathan L; Knijff, Peter de; Morling, Niels; Prinz, Mechthild; Schneider, Peter M; Neste, Christophe Van; Willuweit, Sascha; Phillips, Christopher

    2016-05-01

    The DNA Commission of the International Society for Forensic Genetics (ISFG) is reviewing factors that need to be considered ahead of the adoption by the forensic community of short tandem repeat (STR) genotyping by massively parallel sequencing (MPS) technologies. MPS produces sequence data that provide a precise description of the repeat allele structure of a STR marker and variants that may reside in the flanking areas of the repeat region. When a STR contains a complex arrangement of repeat motifs, the level of genetic polymorphism revealed by the sequence data can increase substantially. As repeat structures can be complex and include substitutions, insertions, deletions, variable tandem repeat arrangements of multiple nucleotide motifs, and flanking region SNPs, established capillary electrophoresis (CE) allele descriptions must be supplemented by a new system of STR allele nomenclature, which retains backward compatibility with the CE data that currently populate national DNA databases and that will continue to be produced for the coming years. Thus, there is a pressing need to produce a standardized framework for describing complex sequences that enable comparison with currently used repeat allele nomenclature derived from conventional CE systems. It is important to discern three levels of information in hierarchical order (i) the sequence, (ii) the alignment, and (iii) the nomenclature of STR sequence data. We propose a sequence (text) string format the minimal requirement of data storage that laboratories should follow when adopting MPS of STRs. We further discuss the variant annotation and sequence comparison framework necessary to maintain compatibility among established and future data. This system must be easy to use and interpret by the DNA specialist, based on a universally accessible genome assembly, and in place before the uptake of MPS by the general forensic community starts to generate sequence data on a large scale. While the established nomenclature for CE-based STR analysis will remain unchanged in the future, the nomenclature of sequence-based STR genotypes will need to follow updated rules and be generated by expert systems that translate MPS sequences to match CE conventions in order to guarantee compatibility between the different generations of STR data. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Whose DNA is this? How relevant a question? (a note for forensic scientists).

    PubMed

    Taroni, Franco; Biedermann, Alex; Vuille, Joëlle; Morling, Niels

    2013-07-01

    This communication seeks to draw the attention of researchers and practitioners dealing with forensic DNA profiling analyses to the following question: is a scientist's report, offering support to a hypothesis according to which a particular individual is the source of DNA detected during the analysis of a stain, relevant from the point of view of a Court of Justice? This question relates to skeptical views previously voiced by commentators mainly in the judicial area, but is avoided by a large majority of forensic scientists. Notwithstanding, the pivotal role of this question has recently been evoked during the international conference "The hidden side of DNA profiles. Artifacts, errors and uncertain evidence" held in Rome (April 27th to 28th, 2012). Indeed, despite the fact that this conference brought together some of the world's leading forensic DNA specialists, it appeared clearly that a huge gap still exists between questions lawyers are actually interested in, and the answers that scientists deliver to Courts in written reports or during oral testimony. Participants in the justice system, namely lawyers and jurors on the one hand and forensic geneticists on the other, unfortunately talk considerably different languages. It thus is fundamental to address this issue of communication about results of forensic DNA analyses, and open a dialogue with practicing non-scientists at large who need to make meaningful use of scientific results to approach and help solve judicial cases. This paper intends to emphasize the actuality of this topic and suggest beneficial ways ahead towards a more reasoned use of forensic DNA in criminal proceedings. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  2. Identification and persistence of Pinus pollen DNA on cotton fabrics: A forensic application.

    PubMed

    Schield, Cassandra; Campelli, Cassandra; Sycalik, Jennifer; Randle, Christopher; Hughes-Stamm, Sheree; Gangitano, David

    2016-01-01

    Advances in plant genomics have had an impact on the field of forensic botany. However, the use of pollen DNA profiling in forensic investigations has yet to be applied. Five volunteers wore a jacket with Pinus echinata pollen-containing cotton swatches for a 14-day period. Pollen decay was evaluated at days 0, 3, 6, 9 and 14 by microscopy. Pollen grains were then transferred to slides using a portable forensic vacuum handle. Ten single grains per swatch were isolated for DNA analysis. DNA was extracted using a high throughput extraction method. A nine-locus short tandem repeat (STR) multiplex system, including previously published primers from Pinus taeda, was developed. DNA was amplified by PCR using fluorescent dyes and analyzed by capillary electrophoresis. Pollen counts from cotton swatches in a 14-day period exhibited an exponential decay from 100% to 17%. The success rate of PCR amplification was 81.2%. Complete and partial STR profiles were generated from 250 pollen grains analyzed (44% and 37%, respectively). Due to the limited amount of DNA, drop-in events were observed (1.87%). However, the rate of contamination with pollen from other pine individuals originating from environmental sources was 4.4%. In conclusion, this study has shown that pollen can be a stable source of forensic DNA evidence, as a proof-of-principle, and that may persist on cotton clothing for at least 14 days of wear. This method can be applied in forensic cases where pollen grains larger than 10 μm (e.g., from herbs or trees) may be transferred to clothing (worn by suspect or victim) by primary contact. Copyright © 2015 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

  3. A first proposal for a general description model of forensic traces

    NASA Astrophysics Data System (ADS)

    Lindauer, Ina; Schäler, Martin; Vielhauer, Claus; Saake, Gunter; Hildebrandt, Mario

    2012-06-01

    In recent years, the amount of digitally captured traces at crime scenes increased rapidly. There are various kinds of such traces, like pick marks on locks, latent fingerprints on various surfaces as well as different micro traces. Those traces are different from each other not only in kind but also in which information they provide. Every kind of trace has its own properties (e.g., minutiae for fingerprints, or raking traces for locks) but there are also large amounts of metadata which all traces have in common like location, time and other additional information in relation to crime scenes. For selected types of crime scene traces, type-specific databases already exist, such as the ViCLAS for sexual offences, the IBIS for ballistic forensics or the AFIS for fingerprints. These existing forensic databases strongly differ in the trace description models. For forensic experts it would be beneficial to work with only one database capable of handling all possible forensic traces acquired at a crime scene. This is especially the case when different kinds of traces are interrelated (e.g., fingerprints and ballistic marks on a bullet casing). Unfortunately, current research on interrelated traces as well as general forensic data models and structures is not mature enough to build such an encompassing forensic database. Nevertheless, recent advances in the field of contact-less scanning make it possible to acquire different kinds of traces with the same device. Therefore the data of these traces is structured similarly what simplifies the design of a general forensic data model for different kinds of traces. In this paper we introduce a first common description model for different forensic trace types. Furthermore, we apply for selected trace types from the well established database schema development process the phases of transferring expert knowledge in the corresponding forensic fields into an extendible, database-driven, generalised forensic description model. The trace types considered here are fingerprint traces, traces at locks, micro traces and ballistic traces. Based on these basic trace types, also combined traces (multiple or overlapped fingerprints, fingerprints on bullet casings, etc) and partial traces are considered.

  4. Microfluidic Devices for Forensic DNA Analysis: A Review.

    PubMed

    Bruijns, Brigitte; van Asten, Arian; Tiggelaar, Roald; Gardeniers, Han

    2016-08-05

    Microfluidic devices may offer various advantages for forensic DNA analysis, such as reduced risk of contamination, shorter analysis time and direct application at the crime scene. Microfluidic chip technology has already proven to be functional and effective within medical applications, such as for point-of-care use. In the forensic field, one may expect microfluidic technology to become particularly relevant for the analysis of biological traces containing human DNA. This would require a number of consecutive steps, including sample work up, DNA amplification and detection, as well as secure storage of the sample. This article provides an extensive overview of microfluidic devices for cell lysis, DNA extraction and purification, DNA amplification and detection and analysis techniques for DNA. Topics to be discussed are polymerase chain reaction (PCR) on-chip, digital PCR (dPCR), isothermal amplification on-chip, chip materials, integrated devices and commercially available techniques. A critical overview of the opportunities and challenges of the use of chips is discussed, and developments made in forensic DNA analysis over the past 10-20 years with microfluidic systems are described. Areas in which further research is needed are indicated in a future outlook.

  5. Evaluation of forensic DNA mixture evidence: protocol for evaluation, interpretation, and statistical calculations using the combined probability of inclusion.

    PubMed

    Bieber, Frederick R; Buckleton, John S; Budowle, Bruce; Butler, John M; Coble, Michael D

    2016-08-31

    The evaluation and interpretation of forensic DNA mixture evidence faces greater interpretational challenges due to increasingly complex mixture evidence. Such challenges include: casework involving low quantity or degraded evidence leading to allele and locus dropout; allele sharing of contributors leading to allele stacking; and differentiation of PCR stutter artifacts from true alleles. There is variation in statistical approaches used to evaluate the strength of the evidence when inclusion of a specific known individual(s) is determined, and the approaches used must be supportable. There are concerns that methods utilized for interpretation of complex forensic DNA mixtures may not be implemented properly in some casework. Similar questions are being raised in a number of U.S. jurisdictions, leading to some confusion about mixture interpretation for current and previous casework. Key elements necessary for the interpretation and statistical evaluation of forensic DNA mixtures are described. Given the most common method for statistical evaluation of DNA mixtures in many parts of the world, including the USA, is the Combined Probability of Inclusion/Exclusion (CPI/CPE). Exposition and elucidation of this method and a protocol for use is the focus of this article. Formulae and other supporting materials are provided. Guidance and details of a DNA mixture interpretation protocol is provided for application of the CPI/CPE method in the analysis of more complex forensic DNA mixtures. This description, in turn, should help reduce the variability of interpretation with application of this methodology and thereby improve the quality of DNA mixture interpretation throughout the forensic community.

  6. Biological Sexing of a 4000-Year-Old Egyptian Mummy Head to Assess the Potential of Nuclear DNA Recovery from the Most Damaged and Limited Forensic Specimens

    PubMed Central

    Loreille, Odile; Ratnayake, Shashikala; Stockwell, Timothy B.; Mallick, Swapan; Skoglund, Pontus; Onorato, Anthony J.; Bergman, Nicholas H.; Reich, David; Irwin, Jodi A.

    2018-01-01

    High throughput sequencing (HTS) has been used for a number of years in the field of paleogenomics to facilitate the recovery of small DNA fragments from ancient specimens. Recently, these techniques have also been applied in forensics, where they have been used for the recovery of mitochondrial DNA sequences from samples where traditional PCR-based assays fail because of the very short length of endogenous DNA molecules. Here, we describe the biological sexing of a ~4000-year-old Egyptian mummy using shotgun sequencing and two established methods of biological sex determination (RX and RY), by way of mitochondrial genome analysis as a means of sequence data authentication. This particular case of historical interest increases the potential utility of HTS techniques for forensic purposes by demonstrating that data from the more discriminatory nuclear genome can be recovered from the most damaged specimens, even in cases where mitochondrial DNA cannot be recovered with current PCR-based forensic technologies. Although additional work remains to be done before nuclear DNA recovered via these methods can be used routinely in operational casework for individual identification purposes, these results indicate substantial promise for the retrieval of probative individually identifying DNA data from the most limited and degraded forensic specimens. PMID:29494531

  7. Crème de la crème in forensic science and legal medicine. The most highly cited articles, authors and journals 1981-2003.

    PubMed

    Jones, Alan Wayne

    2005-03-01

    The importance and prestige of a scientific journal is increasingly being judged by the number of times the articles it publishes are cited or referenced in articles published in other scientific journals. Citation counting is also used to assess the merits of individual scientists when academic promotion and tenure are decided. With the help of Thomson, Institute for Scientific Information (Thomson ISI) a citation database was created for six leading forensic science and legal medicine journals. This database was used to determine the most highly cited articles, authors, journals and the most prolific authors of articles in the forensic sciences. The forensic science and legal medicine journals evaluated were: Journal of Forensic Sciences (JFS), Forensic Science International (FSI), International Journal of Legal Medicine (IJLM), Medicine, Science and the Law (MSL), American Journal of Forensic Medicine and Pathology (AJFMP), and Science and Justice (S&J). The resulting forensics database contained 14,210 papers published between 1981 and 2003. This in-depth bibliometric analysis has identified the creme de la creme in forensic science and legal medicine in a quantitative and objective way by citation analysis with focus on articles, authors and journals.

  8. Use of Embryos Extracted from Individual Cannabis sativa Seeds for Genetic Studies and Forensic Applications.

    PubMed

    Soler, Salvador; Borràs, Dionís; Vilanova, Santiago; Sifres, Alicia; Andújar, Isabel; Figàs, Maria R; Llosa, Ernesto R; Prohens, Jaime

    2016-03-01

    Legal limits on the psychoactive tetrahydrocannabinol (THC) content in Cannabis sativa plants have complicated genetic and forensic studies in this species. However, Cannabis seeds present very low THC levels. We developed a method for embryo extraction from seeds and an improved protocol for DNA extraction and tested this method in four hemp and six marijuana varieties. This embryo extraction method enabled the recovery of diploid embryos from individual seeds. An improved DNA extraction protocol (CTAB3) was used to obtain DNA from individual embryos at a concentration and quality similar to DNA extracted from leaves. DNA extracted from embryos was used for SSR molecular characterization in individuals from the 10 varieties. A unique molecular profile for each individual was obtained, and a clear differentiation between hemp and marijuana varieties was observed. The combined embryo extraction-DNA extraction methodology and the new highly polymorphic SSR markers facilitate genetic and forensic studies in Cannabis. © 2015 American Academy of Forensic Sciences.

  9. More evidence for non-maternal inheritance of mitochondrial DNA?

    PubMed

    Bandelt, H-J; Kong, Q-P; Parson, W; Salas, A

    2005-12-01

    A single case of paternal co-transmission of mitochondrial DNA (mtDNA) in humans has been reported so far. To find potential instances of non-maternal inheritance of mtDNA. Published medical case studies (of single patients) were searched for irregular mtDNA patterns by comparing the given haplotype information for different clones or tissues with the worldwide mtDNA database as known to date-a method that has proved robust and reliable for the detection of flawed mtDNA sequence data. More than 20 studies were found reporting clear cut instances with mtDNAs of different ancestries in single individuals. As examples, cases are reviewed from recent published reports which, at face value, may be taken as evidence for paternal inheritance of mtDNA or recombination. Multiple types (or recombinant types) of quite dissimilar mitochondrial DNA from different parts of the known mtDNA phylogeny are often reported in single individuals. From re-analyses and corrigenda of forensic mtDNA data, it is apparent that the phenomenon of mixed or mosaic mtDNA can be ascribed solely to contamination and sample mix up.

  10. Coverage and overlaps in bibliographic databases relevant to forensic medicine: a comparative analysis of MEDLINE.

    PubMed Central

    Yonker, V A; Young, K P; Beecham, S K; Horwitz, S; Cousin, K

    1990-01-01

    This study was designed to make a comparative evaluation of the performance of MEDLINE in covering serial literature. Forensic medicine was chosen because it is an interdisciplinary subject area that would test MEDLARS at the periphery of the system. The evaluation of database coverage was based upon articles included in the bibliographies of scholars in the field of forensic medicine. This method was considered appropriate for characterizing work used by researchers in this field. The results of comparing MEDLINE to other databases evoked some concerns about the selective indexing policy of MEDLINE in serving the interests of those working in forensic medicine. PMID:2403829

  11. Developmental validation of the IrisPlex system: determination of blue and brown iris colour for forensic intelligence.

    PubMed

    Walsh, Susan; Lindenbergh, Alexander; Zuniga, Sofia B; Sijen, Titia; de Knijff, Peter; Kayser, Manfred; Ballantyne, Kaye N

    2011-11-01

    The IrisPlex system consists of a highly sensitive multiplex genotyping assay together with a statistical prediction model, providing users with the ability to predict blue and brown human eye colour from DNA samples with over 90% precision. This 'DNA intelligence' system is expected to aid police investigations by providing phenotypic information on unknown individuals when conventional DNA profiling is not informative. Falling within the new area of forensic DNA phenotyping, this paper describes the developmental validation of the IrisPlex assay following the Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines for the application of DNA-based eye colour prediction to forensic casework. The IrisPlex assay produces complete SNP genotypes with only 31pg of DNA, approximately six human diploid cell equivalents, and is therefore more sensitive than commercial STR kits currently used in forensics. Species testing revealed human and primate specificity for a complete SNP profile. The assay is capable of producing accurate results from simulated casework samples such as blood, semen, saliva, hair, and trace DNA samples, including extremely low quantity samples. Due to its design, it can also produce full profiles with highly degraded samples often found in forensic casework. Concordance testing between three independent laboratories displayed reproducible results of consistent levels on varying types of simulated casework samples. With such high levels of sensitivity, specificity, consistency and reliability, this genotyping assay, as a core part of the IrisPlex system, operates in accordance with SWGDAM guidelines. Furthermore, as we demonstrated previously, the IrisPlex eye colour prediction system provides reliable results without the need for knowledge on the bio-geographic ancestry of the sample donor. Hence, the IrisPlex system, with its model-based prediction probability estimation of blue and brown human eye colour, represents a useful tool for immediate application in accredited forensic laboratories, to be used for forensic intelligence in tracing unknown individuals from crime scene samples. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  12. Human Provenancing: It's Elemental…

    NASA Astrophysics Data System (ADS)

    Meier-Augenstein, Wolfram; Kemp

    2009-04-01

    Forensic science already uses a variety of methods often in combination to determine a deceased person's identity if neither personal effects nor next of kin (or close friends) can positively identify the victim. While disciplines such as forensic anthropology are able to work from a blank canvass as it were and can provide information on age, gender and ethnical grouping, techniques such as DNA profiling do rely on finding a match either in a database or a comparative sample presumed to be an ante-mortem sample of the victim or from a putative relation. Chances for either to succeed would be greatly enhanced if information gained from a forensic anthropological examination and, circumstances permitting a facial reconstruction could be linked to another technique that can work from a blank canvass or at least does not require comparison to a subject specific database. With the help of isotope ratio mass spectrometry even the very atoms from which a body is made can be used to say something about a person that will help to focus human identification using traditional techniques such as DNA, fingerprints and odontology. Stable isotope fingerprinting works on the basis that almost all chemical elements and in particular the so-called light elements such as carbon (C) that comprise most of the human body occur naturally in different forms, namely isotopes. 2H isotope abundance values recorded by the human body through food and drink ultimately reflect averaged isotopic composition of precipitation or ground water. Stable isotope analysis of 2H isotopic composition in different human tissue such as hair, nails, bone and teeth enables us to construct a time resolved isotopic profile or ‘fingerprint' that may not necessarily permit direct identification of a murder victim or mass disaster victim but in conjunction with forensic anthropological information will provide sufficient intelligence to construct a profile for intelligence lead identification stating where a victim was from (point of origin), how old they were, what their ‘life style' was and even if and where they had recently travelled. Data from several criminal investigations are presented to illustrate potential and limitation of stable isotope analysis of human tissue in aid of victim identification.

  13. Establishing a novel automated magnetic bead-based method for the extraction of DNA from a variety of forensic samples.

    PubMed

    Witt, Sebastian; Neumann, Jan; Zierdt, Holger; Gébel, Gabriella; Röscheisen, Christiane

    2012-09-01

    Automated systems have been increasingly utilized for DNA extraction by many forensic laboratories to handle growing numbers of forensic casework samples while minimizing the risk of human errors and assuring high reproducibility. The step towards automation however is not easy: The automated extraction method has to be very versatile to reliably prepare high yields of pure genomic DNA from a broad variety of sample types on different carrier materials. To prevent possible cross-contamination of samples or the loss of DNA, the components of the kit have to be designed in a way that allows for the automated handling of the samples with no manual intervention necessary. DNA extraction using paramagnetic particles coated with a DNA-binding surface is predestined for an automated approach. For this study, we tested different DNA extraction kits using DNA-binding paramagnetic particles with regard to DNA yield and handling by a Freedom EVO(®)150 extraction robot (Tecan) equipped with a Te-MagS magnetic separator. Among others, the extraction kits tested were the ChargeSwitch(®)Forensic DNA Purification Kit (Invitrogen), the PrepFiler™Automated Forensic DNA Extraction Kit (Applied Biosystems) and NucleoMag™96 Trace (Macherey-Nagel). After an extensive test phase, we established a novel magnetic bead extraction method based upon the NucleoMag™ extraction kit (Macherey-Nagel). The new method is readily automatable and produces high yields of DNA from different sample types (blood, saliva, sperm, contact stains) on various substrates (filter paper, swabs, cigarette butts) with no evidence of a loss of magnetic beads or sample cross-contamination. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  14. The nucleic acid revolution continues – will forensic biology become forensic molecular biology?

    PubMed Central

    Gunn, Peter; Walsh, Simon; Roux, Claude

    2014-01-01

    Molecular biology has evolved far beyond that which could have been predicted at the time DNA identity testing was established. Indeed we should now perhaps be referring to “forensic molecular biology.” Aside from DNA’s established role in identifying the “who” in crime investigations, other developments in medical and developmental molecular biology are now ripe for application to forensic challenges. The impact of DNA methylation and other post-fertilization DNA modifications, plus the emerging role of small RNAs in the control of gene expression, is re-writing our understanding of human biology. It is apparent that these emerging technologies will expand forensic molecular biology to allow for inferences about “when” a crime took place and “what” took place. However, just as the introduction of DNA identity testing engendered many challenges, so the expansion of molecular biology into these domains will raise again the issues of scientific validity, interpretation, probative value, and infringement of personal liberties. This Commentary ponders some of these emerging issues, and presents some ideas on how they will affect the conduct of forensic molecular biology in the foreseeable future. PMID:24634675

  15. Identification of body fluid-specific DNA methylation markers for use in forensic science.

    PubMed

    Park, Jong-Lyul; Kwon, Oh-Hyung; Kim, Jong Hwan; Yoo, Hyang-Sook; Lee, Han-Chul; Woo, Kwang-Man; Kim, Seon-Young; Lee, Seung-Hwan; Kim, Yong Sung

    2014-11-01

    DNA methylation, which occurs at the 5'-position of the cytosine in CpG dinucleotides, has great potential for forensic identification of body fluids, because tissue-specific patterns of DNA methylation have been demonstrated, and DNA is less prone to degradation than proteins or RNA. Previous studies have reported several body fluid-specific DNA methylation markers, but DNA methylation differences are sometimes low in saliva and vaginal secretions. Moreover, specific DNA methylation markers in four types of body fluids (blood, saliva, semen, and vaginal secretions) have not been investigated with genome-wide profiling. Here, we investigated novel DNA methylation markers for identification of body fluids for use in forensic science using the Illumina HumanMethylation 450K bead array, which contains over 450,000 CpG sites. Using methylome data from 16 samples of blood, saliva, semen, and vaginal secretions, we first selected 2986 hypermethylated or hypomethylated regions that were specific for each type of body fluid. We then selected eight CpG sites as novel, forensically relevant DNA methylation markers: cg06379435 and cg08792630 for blood, cg26107890 and cg20691722 for saliva, cg23521140 and cg17610929 for semen, and cg01774894 and cg14991487 for vaginal secretions. These eight selected markers were evaluated in 80 body fluid samples using pyrosequencing, and all showed high sensitivity and specificity for identification of the target body fluid. We suggest that these eight DNA methylation markers may be good candidates for developing an effective molecular assay for identification of body fluids in forensic science. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Mitochondrial sequence analysis for forensic identification using pyrosequencing technology.

    PubMed

    Andréasson, H; Asp, A; Alderborn, A; Gyllensten, U; Allen, M

    2002-01-01

    Over recent years, requests for mtDNA analysis in the field of forensic medicine have notably increased, and the results of such analyses have proved to be very useful in forensic cases where nuclear DNA analysis cannot be performed. Traditionally, mtDNA has been analyzed by DNA sequencing of the two hypervariable regions, HVI and HVII, in the D-loop. DNA sequence analysis using the conventional Sanger sequencing is very robust but time consuming and labor intensive. By contrast, mtDNA analysis based on the pyrosequencing technology provides fast and accurate results from the human mtDNA present in many types of evidence materials in forensic casework. The assay has been developed to determine polymorphic sites in the mitochondrial D-loop as well as the coding region to further increase the discrimination power of mtDNA analysis. The pyrosequencing technology for analysis of mtDNA polymorphisms has been tested with regard to sensitivity, reproducibility, and success rate when applied to control samples and actual casework materials. The results show that the method is very accurate and sensitive; the results are easily interpreted and provide a high success rate on casework samples. The panel of pyrosequencing reactions for the mtDNA polymorphisms were chosen to result in an optimal discrimination power in relation to the number of bases determined.

  17. Public Perceptions and Expectations of the Forensic Use of DNA: Results of a Preliminary Study

    ERIC Educational Resources Information Center

    Curtis, Cate

    2009-01-01

    The forensic use of Deoxyribonucleic Acid (DNA) is demonstrating significant success as a crime-solving tool. However, numerous concerns have been raised regarding the potential for DNA use to contravene cultural, ethical, and legal codes. In this article the expectations and level of knowledge of the New Zealand public of the DNA data-bank and…

  18. Determining the optimal forensic DNA analysis procedure following investigation of sample quality.

    PubMed

    Hedell, Ronny; Hedman, Johannes; Mostad, Petter

    2018-07-01

    Crime scene traces of various types are routinely sent to forensic laboratories for analysis, generally with the aim of addressing questions about the source of the trace. The laboratory may choose to analyse the samples in different ways depending on the type and quality of the sample, the importance of the case and the cost and performance of the available analysis methods. Theoretically well-founded guidelines for the choice of analysis method are, however, lacking in most situations. In this paper, it is shown how such guidelines can be created using Bayesian decision theory. The theory is applied to forensic DNA analysis, showing how the information from the initial qPCR analysis can be utilized. It is assumed the alternatives for analysis are using a standard short tandem repeat (STR) DNA analysis assay, using the standard assay and a complementary assay, or the analysis may be cancelled following quantification. The decision is based on information about the DNA amount and level of DNA degradation of the forensic sample, as well as case circumstances and the cost for analysis. Semi-continuous electropherogram models are used for simulation of DNA profiles and for computation of likelihood ratios. It is shown how tables and graphs, prepared beforehand, can be used to quickly find the optimal decision in forensic casework.

  19. Microfluidic Devices for Forensic DNA Analysis: A Review

    PubMed Central

    Bruijns, Brigitte; van Asten, Arian; Tiggelaar, Roald; Gardeniers, Han

    2016-01-01

    Microfluidic devices may offer various advantages for forensic DNA analysis, such as reduced risk of contamination, shorter analysis time and direct application at the crime scene. Microfluidic chip technology has already proven to be functional and effective within medical applications, such as for point-of-care use. In the forensic field, one may expect microfluidic technology to become particularly relevant for the analysis of biological traces containing human DNA. This would require a number of consecutive steps, including sample work up, DNA amplification and detection, as well as secure storage of the sample. This article provides an extensive overview of microfluidic devices for cell lysis, DNA extraction and purification, DNA amplification and detection and analysis techniques for DNA. Topics to be discussed are polymerase chain reaction (PCR) on-chip, digital PCR (dPCR), isothermal amplification on-chip, chip materials, integrated devices and commercially available techniques. A critical overview of the opportunities and challenges of the use of chips is discussed, and developments made in forensic DNA analysis over the past 10–20 years with microfluidic systems are described. Areas in which further research is needed are indicated in a future outlook. PMID:27527231

  20. Haplotype data for 23 Y-chromosome markers in a reference sample from Bosnia and Herzegovina.

    PubMed

    Kovačević, Lejla; Fatur-Cerić, Vera; Hadzic, Negra; Čakar, Jasmina; Primorac, Dragan; Marjanović, Damir

    2013-06-01

    To detect polymorphisms of 23 Y-chromosomal short tandem repeat (STR) loci, including 6 new loci, in a reference database of male population of Bosnia and Herzegovina, as well as to assess the importance of increasing the number of Y-STR loci utilized in forensic DNA analysis. The reference sample consisted of 100 healthy, unrelated men originating from Bosnia and Herzegovina. Sample collection using buccal swabs was performed in all geographical regions of Bosnia and Herzegovina in the period from 2010 to 2011. DNA samples were typed for 23 Y STR loci, including 6 new loci: DYS576, DYS481, DYS549, DYS533, DYS570, and DYS643, which are included in the new PowerPlex® Y 23 amplification kit. The absolute frequency of generated haplotypes was calculated and results showed that 98 samples had unique Y 23 haplotypes, and that only two samples shared the same haplotype. The most polymorphic locus was DYS418, with 14 detected alleles and the least polymorphic loci were DYS389I, DYS391, DYS437, and DYS393. This study showed that by increasing the number of highly polymorphic Y STR markers, to include those tested in our analysis, leads to a reduction of repeating haplotypes, which is very important in the application of forensic DNA analysis.

  1. Whole genome amplification and real-time PCR in forensic casework

    PubMed Central

    Giardina, Emiliano; Pietrangeli, Ilenia; Martone, Claudia; Zampatti, Stefania; Marsala, Patrizio; Gabriele, Luciano; Ricci, Omero; Solla, Gianluca; Asili, Paola; Arcudi, Giovanni; Spinella, Aldo; Novelli, Giuseppe

    2009-01-01

    Background WGA (Whole Genome Amplification) in forensic genetics can eliminate the technical limitations arising from low amounts of genomic DNA (gDNA). However, it has not been used to date because any amplification bias generated may complicate the interpretation of results. Our aim in this paper was to assess the applicability of MDA to forensic SNP genotyping by performing a comparative analysis of genomic and amplified DNA samples. A 26-SNPs TaqMan panel specifically designed for low copy number (LCN) and/or severely degraded genomic DNA was typed on 100 genomic as well as amplified DNA samples. Results Aliquots containing 1, 0.1 and 0.01 ng each of 100 DNA samples were typed for a 26-SNPs panel. Similar aliquots of the same DNA samples underwent multiple displacement amplification (MDA) before being typed for the same panel. Genomic DNA samples showed 0% PCR failure rate for all three dilutions, whilst the PCR failure rate of the amplified DNA samples was 0% for the 1 ng and 0.1 ng dilutions and 0.077% for the 0.01 ng dilution. The genotyping results of both the amplified and genomic DNA samples were also compared with reference genotypes of the same samples obtained by direct sequencing. The genomic DNA samples showed genotype concordance rates of 100% for all three dilutions while the concordance rates of the amplified DNA samples were 100% for the 1 ng and 0.1 ng dilutions and 99.923% for the 0.01 ng dilution. Moreover, ten artificially-degraded DNA samples, which gave no results when analyzed by current forensic methods, were also amplified by MDA and genotyped with 100% concordance. Conclusion We investigated the suitability of MDA material for forensic SNP typing. Comparative analysis of amplified and genomic DNA samples showed that a large number of SNPs could be accurately typed starting from just 0.01 ng of template. We found that the MDA genotyping call and accuracy rates were only slightly lower than those for genomic DNA. Indeed, when 10 pg of input DNA was used in MDA, we obtained 99.923% concordance, indicating a genotyping error rate of 1/1299 (7.7 × 10-4). This is quite similar to the genotyping error rate of STRs used in current forensic analysis. Such efficiency and accuracy of SNP typing of amplified DNA suggest that MDA can also generate large amounts of genome-equivalent DNA from a minimal amount of input DNA. These results show for the first time that MDA material is suitable for SNP-based forensic protocols and in general when samples fail to give interpretable STR results. PMID:19366436

  2. A novel cell culture model as a tool for forensic biology experiments and validations.

    PubMed

    Feine, Ilan; Shpitzen, Moshe; Roth, Jonathan; Gafny, Ron

    2016-09-01

    To improve and advance DNA forensic casework investigation outcomes, extensive field and laboratory experiments are carried out in a broad range of relevant branches, such as touch and trace DNA, secondary DNA transfer and contamination confinement. Moreover, the development of new forensic tools, for example new sampling appliances, by commercial companies requires ongoing validation and assessment by forensic scientists. A frequent challenge in these kinds of experiments and validations is the lack of a stable, reproducible and flexible biological reference material. As a possible solution, we present here a cell culture model based on skin-derived human dermal fibroblasts. Cultured cells were harvested, quantified and dried on glass slides. These slides were used in adhesive tape-lifting experiments and tests of DNA crossover confinement by UV irradiation. The use of this model enabled a simple and concise comparison between four adhesive tapes, as well as a straightforward demonstration of the effect of UV irradiation intensities on DNA quantity and degradation. In conclusion, we believe this model has great potential to serve as an efficient research tool in forensic biology. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. FaSTR DNA: a new expert system for forensic DNA analysis.

    PubMed

    Power, Timothy; McCabe, Brendan; Harbison, Sally Ann

    2008-06-01

    The automation of DNA profile analysis of reference and crime samples continues to gain pace driven in part by a realisation by the criminal justice system of the positive impact DNA technology can have in aiding in the solution of crime and the apprehension of suspects. Expert systems to automate the profile analysis component of the process are beginning to be developed. In this paper, we report the validation of a new expert system FaSTR DNA, an expert system suitable for the analysis of DNA profiles from single source reference samples and from crime samples. We compare the performance of FaSTR DNA with that of other equivalent systems, GeneMapper ID v3.2 (Applied Biosystems, Foster City, CA) and FSS-i(3) v4 (The Forensic Science Service((R)) DNA expert System Suite FSS-i(3), Forensic Science Service, Birmingham, UK) with GeneScan Analysis v3.7/Genotyper v3.7 software (Applied Biosystems, Foster City, CA, USA) with manual review. We have shown that FaSTR DNA provides an alternative solution to automating DNA profile analysis and is appropriate for implementation into forensic laboratories. The FaSTR DNA system was demonstrated to be comparable in performance to that of GeneMapper ID v3.2 and superior to that of FSS-i(3) v4 for the analysis of DNA profiles from crime samples.

  4. Identifying contributors of two-person DNA mixtures by familial database search.

    PubMed

    Chung, Yuk-Ka; Fung, Wing K

    2013-01-01

    The role of familial database search as a crime-solving tool has been increasingly recognized by forensic scientists. As an enhancement to the existing familial search approach on single source cases, this article presents our current progress in exploring the potential use of familial search to mixture cases. A novel method was established to predict the outcome of the search, from which a simple strategy for determining an appropriate scale of investigation by the police force is developed. Illustrated by an example using Swedish data, our approach is shown to have the potential for assisting the police force to decide on the scale of investigation, thereby achieving desirable crime-solving rate with reasonable cost.

  5. Bodies of science and law: forensic DNA profiling, biological bodies, and biopower.

    PubMed

    Toom, Victor

    2012-01-01

    How is jurisdiction transferred from an individual's biological body to agents of power such as the police, public prosecutors, and the judiciary, and what happens to these biological bodies when transformed from private into public objects? These questions are examined by analysing bodies situated at the intersection of science and law. More specifically, the transformation of ‘private bodies’ into ‘public bodies’ is analysed by going into the details of forensic DNA profiling in the Dutch jurisdiction. It will be argued that various ‘forensic genetic practices’ enact different forensic genetic bodies'. These enacted forensic genetic bodies are connected with various infringements of civil rights, which become articulated in exploring these forensic genetic bodies’‘normative registers’.

  6. A call for more science in forensic science.

    PubMed

    Bell, Suzanne; Sah, Sunita; Albright, Thomas D; Gates, S James; Denton, M Bonner; Casadevall, Arturo

    2018-05-01

    Forensic science is critical to the administration of justice. The discipline of forensic science is remarkably complex and includes methodologies ranging from DNA analysis to chemical composition to pattern recognition. Many forensic practices developed under the auspices of law enforcement and were vetted primarily by the legal system rather than being subjected to scientific scrutiny and empirical testing. Beginning in the 1990s, exonerations based on DNA-related methods revealed problems with some forensic disciplines, leading to calls for major reforms. This process generated a National Academy of Science report in 2009 that was highly critical of many forensic practices and eventually led to the establishment of the National Commission for Forensic Science (NCFS) in 2013. The NCFS was a deliberative body that catalyzed communication between nonforensic scientists, forensic scientists, and other stakeholders in the legal community. In 2017, despite continuing problems with forensic science, the Department of Justice terminated the NCFS. Just when forensic science needs the most support, it is getting the least. We urge the larger scientific community to come to the aid of our forensic colleagues by advocating for urgently needed research, testing, and financial support.

  7. EMPOP-quality mtDNA control region sequences from Kashmiri of Azad Jammu & Kashmir, Pakistan.

    PubMed

    Rakha, Allah; Peng, Min-Sheng; Bi, Rui; Song, Jiao-Jiao; Salahudin, Zeenat; Adan, Atif; Israr, Muhammad; Yao, Yong-Gang

    2016-11-01

    The mitochondrial DNA (mtDNA) control region (nucleotide position 16024-576) sequences were generated through Sanger sequencing method for 317 self-identified Kashmiris from all districts of Azad Jammu & Kashmir Pakistan. The population sample set showed a total of 251 haplotypes, with a relatively high haplotype diversity (0.9977) and a low random match probability (0.54%). The containing matrilineal lineages belonging to three different phylogeographic origins of Western Eurasian (48.9%), South Asian (47.0%) and East Asian (4.1%). The present study was compared to previous data from Pakistan and other worldwide populations (Central Asia, Western Asia, and East & Southeast Asia). The dataset is made available through EMPOP under accession number EMP00679 and will serve as an mtDNA reference database in forensic casework in Pakistan. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. Development of a 20-locus fluorescent multiplex system as a valuable tool for national DNA database.

    PubMed

    Jiang, Xianhua; Guo, Fei; Jia, Fei; Jin, Ping; Sun, Zhu

    2013-02-01

    The multiplex system allows the detection of 19 autosomal short tandem repeat (STR) loci [including all Combined DNA Index System (CODIS) STR loci as well as D2S1338, D6S1043, D12S391, D19S433, Penta D and Penta E] plus the sex-determining locus Amelogenin in a single reaction, comprising all STR loci in various commercial kits used in the China national DNA database (NDNAD). Primers are designed so that the amplicons are distributed ranging from 90 base pairs (bp) to 450 bp within a five-dye fluorescent design with the fifth dye reserved for the internal size standard. With 30 cycles, 125 pg to 2 ng DNA template showed optimal profiling result, while robust profiles could also be achieved by adjusting the cycle numbers for the DNA template beyond that optimal DNA input range. Mixture studies showed that 83% and 87% of minor alleles were detected at 9:1 and 1:9 ratios, respectively. When 4 ng of degraded DNA was digested by 2-min DNase and 1 ng undegraded DNA was added to 400 μM haematin, the complete profiles were still observed. Polymerase chain reaction (PCR)-based procedures were examined and optimized including the concentrations of primer set, magnesium and the Taq polymerase as well as volume, cycle number and annealing temperature. In addition, the system has been validated by 3000 bloodstain samples and 35 common case samples in line with the Chinese National Standards and Scientific Working Group on DNA Analysis Methods (SWGDAM) guidelines. The total probability of identity (TPI) can reach to 8×10(-24), where DNA database can be improved at the level of 10 million DNA profiles or more because the number of expected match is far from one person (4×10(-10)) and can be negligible. Further, our system also demonstrates its good performance in case samples and it will be an ideal tool for forensic DNA typing and databasing with potential application. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  9. Utility of GenBank and the Barcode of Life Data Systems (BOLD) for the identification of forensically important Diptera from Belgium and France

    PubMed Central

    Sonet, Gontran; Jordaens, Kurt; Braet, Yves; Bourguignon, Luc; Dupont, Eréna; Backeljau, Thierry; De Meyer, Marc; Desmyter, Stijn

    2013-01-01

    Abstract Fly larvae living on dead corpses can be used to estimate post-mortem intervals. The identification of these flies is decisive in forensic casework and can be facilitated by using DNA barcodes provided that a representative and comprehensive reference library of DNA barcodes is available. We constructed a local (Belgium and France) reference library of 85 sequences of the COI DNA barcode fragment (mitochondrial cytochrome c oxidase subunit I gene), from 16 fly species of forensic interest (Calliphoridae, Muscidae, Fanniidae). This library was then used to evaluate the ability of two public libraries (GenBank and the Barcode of Life Data Systems – BOLD) to identify specimens from Belgian and French forensic cases. The public libraries indeed allow a correct identification of most specimens. Yet, some of the identifications remain ambiguous and some forensically important fly species are not, or insufficiently, represented in the reference libraries. Several search options offered by GenBank and BOLD can be used to further improve the identifications obtained from both libraries using DNA barcodes. PMID:24453564

  10. Likelihood ratio and posterior odds in forensic genetics: Two sides of the same coin.

    PubMed

    Caliebe, Amke; Walsh, Susan; Liu, Fan; Kayser, Manfred; Krawczak, Michael

    2017-05-01

    It has become widely accepted in forensics that, owing to a lack of sensible priors, the evidential value of matching DNA profiles in trace donor identification or kinship analysis is most sensibly communicated in the form of a likelihood ratio (LR). This restraint does not abate the fact that the posterior odds (PO) would be the preferred basis for returning a verdict. A completely different situation holds for Forensic DNA Phenotyping (FDP), which is aimed at predicting externally visible characteristics (EVCs) of a trace donor from DNA left behind at the crime scene. FDP is intended to provide leads to the police investigation helping them to find unknown trace donors that are unidentifiable by DNA profiling. The statistical models underlying FDP typically yield posterior odds (PO) for an individual possessing a certain EVC. This apparent discrepancy has led to confusion as to when LR or PO is the appropriate outcome of forensic DNA analysis to be communicated to the investigating authorities. We thus set out to clarify the distinction between LR and PO in the context of forensic DNA profiling and FDP from a statistical point of view. In so doing, we also addressed the influence of population affiliation on LR and PO. In contrast to the well-known population dependency of the LR in DNA profiling, the PO as obtained in FDP may be widely population-independent. The actual degree of independence, however, is a matter of (i) how much of the causality of the respective EVC is captured by the genetic markers used for FDP and (ii) by the extent to which non-genetic such as environmental causal factors of the same EVC are distributed equally throughout populations. The fact that an LR should be communicated in cases of DNA profiling whereas the PO are suitable for FDP does not conflict with theory, but rather reflects the immanent differences between these two forensic applications of DNA information. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Potential relationship between single nucleotide polymorphisms used in forensic genetics and diseases or other traits in European population.

    PubMed

    Pombar-Gomez, Maria; Lopez-Lopez, Elixabet; Martin-Guerrero, Idoia; Garcia-Orad Carles, Africa; de Pancorbo, Marian M

    2015-05-01

    Single nucleotide polymorphisms (SNPs) are an interesting option to facilitate the analysis of highly degraded DNA by allowing the reduction of the size of the DNA amplicons. The SNPforID 52-plex panel is a clear example of the use of non-coding SNPs in forensic genetics. However, nonstop advances in studies of genetic polymorphisms are leading to the discovery of new associations between SNPs and diseases. The aim of this study was to perform a comprehensive review of the state of association between the 52 SNPs in the 52-plex panel and diseases or other traits related to their treatment, such as drug response characters. In order to achieve this goal, we have conducted a bioinformatic search for each SNP included in the panel and the SNPs in linkage disequilibrium (LD) with them in the European population (r (2)  > 0.8). A total of 424 SNPs (52 in the panel and 372 in LD) were investigated in PubMed, Scopus, and dbSNP databases. Our results show that three SNPs in the SNPforID 52-plex panel (rs2107612, rs1979255, rs1463729) have been associated with diseases such as hypertension or macular degeneration, as well as drug response. Similarly, three out of the 372 SNPs in LD (rs2107614, r (2)  = 0.859; rs765250, r (2)  = 0.858; rs11064560, r (2)  = 0,887) are also associated with various pathologies. In view of these results, we propose the need for a periodic review of the SNPs used in forensic genetics in order to keep their associations with diseases or related phenotypes updated and to evaluate their continuity in forensic panels for avoiding legal and ethical conflicts.

  12. The Development and Use of Internal Amplification Controls (IACs) with DNA Profiling Kits for Forensic DNA Analysis.

    PubMed

    Zahra, Nathalie; Goodwin, William

    2016-01-01

    Biological samples recovered for forensic investigations are often degraded and/or have low amounts of DNA; in addition, in some instances the samples may be contaminated with chemicals that can act as PCR inhibitors. As a consequence this can make interpretation of the results challenging with the possibility of having partial profiles and false negative results. Because of the impact of DNA analysis on forensic investigations, it is important to monitor the process of DNA profiling, in particular the amplification reaction. In this chapter we describe a method for the in-house generation and use of internal amplification controls (IACs) with DNA profiling kits to monitor the success of the PCR proces. In the example we show the use of the SGM Plus® kit. These controls can also be used to aid the interpretation of the DNA profile.

  13. DNA methylation-based age prediction from various tissues and body fluids

    PubMed Central

    Jung, Sang-Eun; Shin, Kyoung-Jin; Lee, Hwan Young

    2017-01-01

    Aging is a natural and gradual process in human life. It is influenced by heredity, environment, lifestyle, and disease. DNA methylation varies with age, and the ability to predict the age of donor using DNA from evidence materials at a crime scene is of considerable value in forensic investigations. Recently, many studies have reported age prediction models based on DNA methylation from various tissues and body fluids. Those models seem to be very promising because of their high prediction accuracies. In this review, the changes of age-associated DNA methylation and the age prediction models for various tissues and body fluids were examined, and then the applicability of the DNA methylation-based age prediction method to the forensic investigations was discussed. This will improve the understandings about DNA methylation markers and their potential to be used as biomarkers in the forensic field, as well as the clinical field. PMID:28946940

  14. Basic research in evolution and ecology enhances forensics.

    PubMed

    Tomberlin, Jeffery K; Benbow, M Eric; Tarone, Aaron M; Mohr, Rachel M

    2011-02-01

    In 2009, the National Research Council recommended that the forensic sciences strengthen their grounding in basic empirical research to mitigate against criticism and improve accuracy and reliability. For DNA-based identification, this goal was achieved under the guidance of the population genetics community. This effort resulted in DNA analysis becoming the 'gold standard' of the forensic sciences. Elsewhere, we proposed a framework for streamlining research in decomposition ecology, which promotes quantitative approaches to collecting and applying data to forensic investigations involving decomposing human remains. To extend the ecological aspects of this approach, this review focuses on forensic entomology, although the framework can be extended to other areas of decomposition. Published by Elsevier Ltd.

  15. Developing a new nonbinary SNP fluorescent multiplex detection system for forensic application in China.

    PubMed

    Liu, Yanfang; Liao, Huidan; Liu, Ying; Guo, Juanjuan; Sun, Yi; Fu, Xiaoliang; Xiao, Ding; Cai, Jifeng; Lan, Lingmei; Xie, Pingli; Zha, Lagabaiyila

    2017-04-01

    Nonbinary single-nucleotide polymorphisms (SNPs) are potential forensic genetic markers because their discrimination power is greater than that of normal binary SNPs, and that they can detect highly degraded samples. We previously developed a nonbinary SNP multiplex typing assay. In this study, we selected additional 20 nonbinary SNPs from the NCBI SNP database and verified them through pyrosequencing. These 20 nonbinary SNPs were analyzed using the fluorescent-labeled SNaPshot multiplex SNP typing method. The allele frequencies and genetic parameters of these 20 nonbinary SNPs were determined among 314 unrelated individuals from Han populations from China. The total power of discrimination was 0.9999999999994, and the cumulative probability of exclusion was 0.9986. Moreover, the result of the combination of this 20 nonbinary SNP assay with the 20 nonbinary SNP assay we previously developed demonstrated that the cumulative probability of exclusion of the 40 nonbinary SNPs was 0.999991 and that no significant linkage disequilibrium was observed in all 40 nonbinary SNPs. Thus, we concluded that this new system consisting of new 20 nonbinary SNPs could provide highly informative polymorphic data which would be further used in forensic application and would serve as a potentially valuable supplement to forensic DNA analysis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. FBI's DNA analysis program

    NASA Astrophysics Data System (ADS)

    Brown, John R.

    1994-03-01

    Forensic DNA profiling technology is a significant law enforcement tool due to its superior discriminating power. Applying the principles of population genetics to the DNA profile obtained in violent crime investigations results in low frequency of occurrence estimates for the DNA profile. These estimates often range from a frequency of occurrence of 1 in 50 unrelated individuals to 1 in a million unrelated individuals or even smaller. It is this power to discriminate among individuals in the population that has propelled forensic DNA technology to the forefront of forensic testing in violent crime cases. Not only is the technology extremely powerful in including or excluding a criminal suspect as the perpetrator, but it also gives rise to the potential of identifying criminal suspects in cases where the investigators of unknown suspect cases have exhausted all other available leads.

  17. Massively parallel sequencing and the emergence of forensic genomics: Defining the policy and legal issues for law enforcement.

    PubMed

    Scudder, Nathan; McNevin, Dennis; Kelty, Sally F; Walsh, Simon J; Robertson, James

    2018-03-01

    Use of DNA in forensic science will be significantly influenced by new technology in coming years. Massively parallel sequencing and forensic genomics will hasten the broadening of forensic DNA analysis beyond short tandem repeats for identity towards a wider array of genetic markers, in applications as diverse as predictive phenotyping, ancestry assignment, and full mitochondrial genome analysis. With these new applications come a range of legal and policy implications, as forensic science touches on areas as diverse as 'big data', privacy and protected health information. Although these applications have the potential to make a more immediate and decisive forensic intelligence contribution to criminal investigations, they raise policy issues that will require detailed consideration if this potential is to be realised. The purpose of this paper is to identify the scope of the issues that will confront forensic and user communities. Copyright © 2017 The Chartered Society of Forensic Sciences. All rights reserved.

  18. Choice of population database for forensic DNA profile analysis.

    PubMed

    Steele, Christopher D; Balding, David J

    2014-12-01

    When evaluating the weight of evidence (WoE) for an individual to be a contributor to a DNA sample, an allele frequency database is required. The allele frequencies are needed to inform about genotype probabilities for unknown contributors of DNA to the sample. Typically databases are available from several populations, and a common practice is to evaluate the WoE using each available database for each unknown contributor. Often the most conservative WoE (most favourable to the defence) is the one reported to the court. However the number of human populations that could be considered is essentially unlimited and the number of contributors to a sample can be large, making it impractical to perform every possible WoE calculation, particularly for complex crime scene profiles. We propose instead the use of only the database that best matches the ancestry of the queried contributor, together with a substantial FST adjustment. To investigate the degree of conservativeness of this approach, we performed extensive simulations of one- and two-contributor crime scene profiles, in the latter case with, and without, the profile of the second contributor available for the analysis. The genotypes were simulated using five population databases, which were also available for the analysis, and evaluations of WoE using our heuristic rule were compared with several alternative calculations using different databases. Using FST=0.03, we found that our heuristic gave WoE more favourable to the defence than alternative calculations in well over 99% of the comparisons we considered; on average the difference in WoE was just under 0.2 bans (orders of magnitude) per locus. The degree of conservativeness of the heuristic rule can be adjusted through the FST value. We propose the use of this heuristic for DNA profile WoE calculations, due to its ease of implementation, and efficient use of the evidence while allowing a flexible degree of conservativeness. Copyright © 2014. Published by Elsevier Ireland Ltd.

  19. Laser mass spectrometry for DNA fingerprinting for forensic applications

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, C.H.; Tang, K.; Taranenko, N.I.

    The application of DNA fingerprinting has become very broad in forensic analysis, patient identification, diagnostic medicine, and wildlife poaching, since every individual`s DNA structure is identical within all tissues of their body. DNA fingerprinting was initiated by the use of restriction fragment length polymorphisms (RFLP). In 1987, Nakamura et al. found that a variable number of tandem repeats (VNTR) often occurred in the alleles. The probability of different individuals having the same number of tandem repeats in several different alleles is very low. Thus, the identification of VNTR from genomic DNA became a very reliable method for identification of individuals.more » DNA fingerprinting is a reliable tool for forensic analysis. In DNA fingerprinting, knowledge of the sequence of tandem repeats and restriction endonuclease sites can provide the basis for identification. The major steps for conventional DNA fingerprinting include (1) specimen processing (2) amplification of selected DNA segments by PCR, and (3) gel electrophoresis to do the final DNA analysis. In this work we propose to use laser desorption mass spectrometry for fast DNA fingerprinting. The process and advantages are discussed.« less

  20. Development of a novel forensic STR multiplex for ancestry analysis and extended identity testing.

    PubMed

    Phillips, Chris; Fernandez-Formoso, Luis; Gelabert-Besada, Miguel; Garcia-Magariños, Manuel; Santos, Carla; Fondevila, Manuel; Carracedo, Angel; Lareu, Maria Victoria

    2013-04-01

    There is growing interest in developing additional DNA typing techniques to provide better investigative leads in forensic analysis. These include inference of genetic ancestry and prediction of common physical characteristics of DNA donors. To date, forensic ancestry analysis has centered on population-divergent SNPs but these binary loci cannot reliably detect DNA mixtures, common in forensic samples. Furthermore, STR genotypes, forming the principal DNA profiling system, are not routinely combined with forensic SNPs to strengthen frequency data available for ancestry inference. We report development of a 12-STR multiplex composed of ancestry informative marker STRs (AIM-STRs) selected from 434 tetranucleotide repeat loci. We adapted our online Bayesian classifier for AIM-SNPs: Snipper, to handle multiallele STR data using frequency-based training sets. We assessed the ability of the 12-plex AIM-STRs to differentiate CEPH Human Genome Diversity Panel populations, plus their informativeness combined with established forensic STRs and AIM-SNPs. We found combining STRs and SNPs improves the success rate of ancestry assignments while providing a reliable mixture detection system lacking from SNP analysis alone. As the 12 STRs generally show a broad range of alleles in all populations, they provide highly informative supplementary STRs for extended relationship testing and identification of missing persons with incomplete reference pedigrees. Lastly, mixed marker approaches (combining STRs with binary loci) for simple ancestry inference tests beyond forensic analysis bring advantages and we discuss the genotyping options available. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Prevention of DNA contamination during forensic medical examinations in a clinical forensic medical service: A best practice implementation project.

    PubMed

    Lutz, Tasha

    2015-01-01

    Contamination of forensic specimens can have significant and detrimental effects on cases presented in court. In 2010 a wrongful conviction in Australia resulted in an inquiry with 25 recommendations to minimize the risk of DNA contamination of forensic specimens. DNA decontamination practices in a clinical forensic medical service currently attempt to comply with these recommendations. Evaluation of these practices has not been undertaken. The aim of this project was to audit the current DNA decontamination practices of forensic medical and nursing examiners in the forensic medical examination process and implement changes based on the audit findings. A re-audit following implementation would be undertaken to identify change and inform further research. The Joanna Briggs Institute's Practical Application of Clinical Evidence System and Getting Research into Practice were used as the audit tool in this project. A baseline audit was conducted; analysis of this audit process was then undertaken. Following education and awareness training targeted at clinicians, a re-audit was completed. There were a total of 24 audit criteria; the baseline audit reflected 20 of these criteria had 100% compliance. The remaining 4 audit criteria demonstrated compliance between 65% and 90%. Education and awareness training resulted in improved compliance in 2 of the 4 audit criteria, with the remaining 2 having unchanged compliance. The findings demonstrated that education and raising awareness can improve clinical practice; however there are also external factors outside the control of the clinicians that influence compliance with best practice.

  2. Automated PCR setup for forensic casework samples using the Normalization Wizard and PCR Setup robotic methods.

    PubMed

    Greenspoon, S A; Sykes, K L V; Ban, J D; Pollard, A; Baisden, M; Farr, M; Graham, N; Collins, B L; Green, M M; Christenson, C C

    2006-12-20

    Human genome, pharmaceutical and research laboratories have long enjoyed the application of robotics to performing repetitive laboratory tasks. However, the utilization of robotics in forensic laboratories for processing casework samples is relatively new and poses particular challenges. Since the quantity and quality (a mixture versus a single source sample, the level of degradation, the presence of PCR inhibitors) of the DNA contained within a casework sample is unknown, particular attention must be paid to procedural susceptibility to contamination, as well as DNA yield, especially as it pertains to samples with little biological material. The Virginia Department of Forensic Science (VDFS) has successfully automated forensic casework DNA extraction utilizing the DNA IQ(trade mark) System in conjunction with the Biomek 2000 Automation Workstation. Human DNA quantitation is also performed in a near complete automated fashion utilizing the AluQuant Human DNA Quantitation System and the Biomek 2000 Automation Workstation. Recently, the PCR setup for casework samples has been automated, employing the Biomek 2000 Automation Workstation and Normalization Wizard, Genetic Identity version, which utilizes the quantitation data, imported into the software, to create a customized automated method for DNA dilution, unique to that plate of DNA samples. The PCR Setup software method, used in conjunction with the Normalization Wizard method and written for the Biomek 2000, functions to mix the diluted DNA samples, transfer the PCR master mix, and transfer the diluted DNA samples to PCR amplification tubes. Once the process is complete, the DNA extracts, still on the deck of the robot in PCR amplification strip tubes, are transferred to pre-labeled 1.5 mL tubes for long-term storage using an automated method. The automation of these steps in the process of forensic DNA casework analysis has been accomplished by performing extensive optimization, validation and testing of the software methods.

  3. A simple automated instrument for DNA extraction in forensic casework.

    PubMed

    Montpetit, Shawn A; Fitch, Ian T; O'Donnell, Patrick T

    2005-05-01

    The Qiagen BioRobot EZ1 is a small, rapid, and reliable automated DNA extraction instrument capable of extracting DNA from up to six samples in as few as 20 min using magnetic bead technology. The San Diego Police Department Crime Laboratory has validated the BioRobot EZ1 for the DNA extraction of evidence and reference samples in forensic casework. The BioRobot EZ1 was evaluated for use on a variety of different evidence sample types including blood, saliva, and semen evidence. The performance of the BioRobot EZ1 with regard to DNA recovery and potential cross-contamination was also assessed. DNA yields obtained with the BioRobot EZ1 were comparable to those from organic extraction. The BioRobot EZ1 was effective at removing PCR inhibitors, which often co-purify with DNA in organic extractions. The incorporation of the BioRobot EZ1 into forensic casework has streamlined the DNA analysis process by reducing the need for labor-intensive phenol-chloroform extractions.

  4. A review of state legislation on DNA forensic data banking.

    PubMed Central

    McEwen, J. E.; Reilly, P. R.

    1994-01-01

    Recent advances in DNA identification technology are making their way into the criminal law. States across the country are enacting legislation to create repositories for the storage both of DNA samples collected from convicted offenders and of the DNA profiles derived from them. These data banks will be used to assist in the resolution of future crimes. This study surveys existing state statues, pending legislation, and administrative regulations that govern these DNA forensic data banks. We critically analyzed these laws with respect to their treatment of the collection, storage, analysis, retrieval, and use of DNA and DNA data. We found much variation among data-banking laws and conclude that, while DNA forensic data banking carries tremendous potential for law enforcement, many states, in their rush to create data banks, have paid little attention to issues of quality control, quality assurance, and privacy. In addition, the sweep of some laws is unnecessarily broad. Legislative modifications are needed in many states to better safeguard civil liberties and individual privacy. PMID:8198138

  5. DNA Profiling Success Rates from Degraded Skeletal Remains in Guatemala.

    PubMed

    Johnston, Emma; Stephenson, Mishel

    2016-07-01

    No data are available regarding the success of DNA Short Tandem Repeat (STR) profiling from degraded skeletal remains in Guatemala. Therefore, DNA profiling success rates relating to 2595 skeletons from eleven cases at the Forensic Anthropology Foundation of Guatemala (FAFG) are presented. The typical postmortem interval was 30 years. DNA was extracted from bone powder and amplified using Identifiler and Minifler. DNA profiling success rates differed between cases, ranging from 50.8% to 7.0%, the overall success rate for samples was 36.3%. The best DNA profiling success rates were obtained from femur (36.2%) and tooth (33.7%) samples. DNA profiles were significantly better from lower body bones than upper body bones (p = <0.0001). Bone samples from males gave significantly better profiles than samples from females (p = <0.0001). These results are believed to be related to bone density. The findings are important for designing forensic DNA sampling strategies in future victim recovery investigations. © 2016 American Academy of Forensic Sciences.

  6. Investigating CSI: portrayals of DNA testing on a forensic crime show and their potential effects.

    PubMed

    Ley, Barbara L; Jankowski, Natalie; Brewer, Paul R

    2012-01-01

    The popularity of forensic crime shows such as CSI has fueled debate about their potential social impact. This study considers CSI's potential effects on public understandings regarding DNA testing in the context of judicial processes, the policy debates surrounding crime laboratory procedures, and the forensic science profession, as well as an effect not discussed in previous accounts: namely, the show's potential impact on public understandings of DNA and genetics more generally. To develop a theoretical foundation for research on the "CSI effect," it draws on cultivation theory, social cognitive theory, and audience reception studies. It then uses content analysis and textual analysis to illuminate how the show depicts DNA testing. The results demonstrate that CSI tends to depict DNA testing as routine, swift, useful, and reliable and that it echoes broader discourses about genetics. At times, however, the show suggests more complex ways of thinking about DNA testing and genetics.

  7. Reduction of Powerplex(®) Y23 reaction volume for genotyping buccal cell samples on FTA(TM) cards.

    PubMed

    Raziel, Aliza; Dell'Ariccia-Carmon, Aviva; Zamir, Ashira

    2015-01-01

    PowerPlex(®) Y23 is a novel kit for Y-STR typing that includes new highly discriminating loci. The Israel DNA Database laboratory has recently adopted it for routine Y-STR analysis. This study examined PCR amplification from 1.2-mm FTA punch in reduced volumes of 5 and 10 μL. Direct amplification and washing of the FTA punches were examined in different PCR cycle numbers. One short robotically performed wash was found to improve the quality and the percent of profiles obtained. The optimal PCR cycle number was determined for 5 and 10 μL reaction volumes. The percent of obtained profiles, color balance, and reproducibility were examined. High-quality profiles were achieved in 90% and 88% of the samples amplified in 5 and 10 μL, respectively, in the first attempt. Volume reduction to 5 μL has a vast economic impact especially for DNA database laboratories. © 2014 American Academy of Forensic Sciences.

  8. Resolution of aviation forensic toxicology findings with the aid of DNA profiling.

    PubMed

    Chaturvedi, Arvind K; Craft, Kristi J; Kupfer, Doris M; Burian, Dennis; Canfield, Dennis V

    2011-03-20

    Body components of aviation accident fatalities are often scattered, disintegrated, commingled, contaminated, and/or putrefied at accident scenes. These situations may impose difficulties in victim identification/tissue matching. The prevalence of misidentification in relation to aviation accident forensic toxicology has not been well established. Therefore, the Civil Aerospace Medical Institute (CAMI) toxicology database was searched for the 1998-2008 period for those cases wherein DNA profiling was performed to resolve identity issue of the samples submitted to CAMI for toxicological evaluation. During this period, biological samples from the casualties of a total of 3523 accidents were submitted to CAMI. The submitted samples were primarily from pilots. Out of the 3523 accidents, at least, one fatality had occurred in 3366 (≈ 96%) accidents; thus, these accidents were considered fatal accidents. Accordingly, biological samples from 3319 pilots (3319 of the 3366 accidents) were received at CAMI for toxicological testing. Of these 3319 pilots, 3275 (≈ 99%) were fatally injured. DNA profiling was performed in 15 (≈ 0.5%) of the 3319 accidents. The profiling was conducted upon the requests of families in two accidents, accident investigators in three, and pathologists in four. In six accidents, contradictory toxicological findings led CAMI to initiate DNA profiling. The requests made by families and investigators were primarily triggered by inconsistency between the toxicological results and the history of drug use of the victims, while by pathologists because of commingling of samples. In three (20%) of the 15 accidents, at least one submitted sample was misidentified or mislabeled. The present study demonstrated that the number of aviation accident cases requiring DNA profiling was small and this DNA approach was effectively applied in resolving aviation toxicology findings associated with those accidents. Published by Elsevier Ireland Ltd.

  9. Curriculum and course materials for a forensic DNA biology course.

    PubMed

    Elkins, Kelly M

    2014-01-01

    The Forensic Science Education Programs Accreditation Commission (FEPAC) requires accredited programs offer a "coherent curriculum" to ensure each student gains a "thorough grounding of the natural…sciences." Part of this curriculum includes completion of a minimum of 15 semester-hours forensic science coursework, nine of which can involve a class in forensic DNA biology. Departments that have obtained or are pursuing FEPAC accreditation can meet this requirement by offering a stand-alone forensic DNA biology course; however, materials necessary to instruct students are often homegrown and not standardized; in addition, until recently, the community lacked commercially available books, lab manuals, and teaching materials, and many of the best pedagogical resources were scattered across various peer-reviewed journals. The curriculum discussed below is an attempt to synthesize this disparate information, and although certainly not the only acceptable methodology, the below discussion represents "a way" for synthesizing and aggregating this information into a cohesive, comprehensive whole. Copyright © 2013 by The International Union of Biochemistry and Molecular Biology.

  10. Developing a spatial-temporal method for the geographic investigation of shoeprint evidence.

    PubMed

    Lin, Ge; Elmes, Gregory; Walnoha, Mike; Chen, Xiannian

    2009-01-01

    This article examines the potential of a spatial-temporal method for analysis of forensic shoeprint data. The large volume of shoeprint evidence recovered at crime scenes results in varied success in matching a print to a known shoe type and subsequently linking sets of matched prints to suspected offenders. Unlike DNA and fingerprint data, a major challenge is to reduce the uncertainty in linking sets of matched shoeprints to a suspected serial offender. Shoeprint data for 2004 were imported from the Greater London Metropolitan Area Bigfoot database into a geographic information system, and a spatial-temporal algorithm developed for this project. The results show that by using distance and time constraints interactively, the number of candidate shoeprints that can implicate one or few suspects can be substantially reduced. It concludes that the use of space-time and other ancillary information within a geographic information system can be quite helpful for forensic investigation.

  11. Forensic and phylogeographic characterisation of mtDNA lineages from Somalia.

    PubMed

    Mikkelsen, Martin; Fendt, Liane; Röck, Alexander W; Zimmermann, Bettina; Rockenbauer, Eszter; Hansen, Anders J; Parson, Walther; Morling, Niels

    2012-07-01

    The African mitochondrial (mt) phylogeny is coarsely resolved but the majority of population data generated so far is limited to the analysis of the first hypervariable segment (HVS-1) of the control region (CR). Therefore, this study aimed on the investigation of the entire CR of 190 unrelated Somali individuals to enrich the severely underrepresented African mtDNA pool. The majority (60.5 %) of the haplotypes were of sub-Saharan origin with L0a1d, L2a1h and L3f being the most frequently observed haplogroups. This is in sharp contrast to previous data reported from the Y-chromosome, where only about 5 % of the observed haplogroups were of sub-Saharan provenance. We compared the genetic distances based on population pairwise F (st) values between 11 published East, Central and North African as well as western Asian populations and the Somali sequences and displayed them in a multi-dimensional scaling plot. Genetic proximity evidenced by clustering roughly reflected the relative geographic location of the populations. The sequences will be included in the EMPOP database ( www.empop.org ) under accession number EMP00397 upon publication (Parson and Dür Forensic Sci Int Genet 1:88-92, 2007).

  12. A technique for setting analytical thresholds in massively parallel sequencing-based forensic DNA analysis

    PubMed Central

    2017-01-01

    Amplicon (targeted) sequencing by massively parallel sequencing (PCR-MPS) is a potential method for use in forensic DNA analyses. In this application, PCR-MPS may supplement or replace other instrumental analysis methods such as capillary electrophoresis and Sanger sequencing for STR and mitochondrial DNA typing, respectively. PCR-MPS also may enable the expansion of forensic DNA analysis methods to include new marker systems such as single nucleotide polymorphisms (SNPs) and insertion/deletions (indels) that currently are assayable using various instrumental analysis methods including microarray and quantitative PCR. Acceptance of PCR-MPS as a forensic method will depend in part upon developing protocols and criteria that define the limitations of a method, including a defensible analytical threshold or method detection limit. This paper describes an approach to establish objective analytical thresholds suitable for multiplexed PCR-MPS methods. A definition is proposed for PCR-MPS method background noise, and an analytical threshold based on background noise is described. PMID:28542338

  13. Mitochondria in anthropology and forensic medicine.

    PubMed

    Grzybowski, Tomasz; Rogalla, Urszula

    2012-01-01

    Mitochondria's role in crucial metabolic pathways is probably the first answer which comes to our minds for the question: what do these tiny organelles serve for? However, specific features of their DNA made them extremely useful also in the field of anthropology and forensics. MtDNA analyses became a milestone in the complex task of unraveling earliest human migrations. Evidence provided by these experiments left no doubts on modern humans origins pointing to Africa being our cradle. It also contributed to interpretation of putative ways of our dispersal around Asia and Americas thousands years ago. On the other hand, analysis of mtDNA is well established and valuable tool in forensic genetics. When other definitely more popular markers give no answer on identity, it is the time to employ information carried by mitochondria. This chapter summarizes not only current reports on the role of mitochondria in forensics and reconstruction of modern humans phylogeny, but also calls one's attention to a broad range of difficulties and constraints associated with mtDNA analyses.

  14. A technique for setting analytical thresholds in massively parallel sequencing-based forensic DNA analysis.

    PubMed

    Young, Brian; King, Jonathan L; Budowle, Bruce; Armogida, Luigi

    2017-01-01

    Amplicon (targeted) sequencing by massively parallel sequencing (PCR-MPS) is a potential method for use in forensic DNA analyses. In this application, PCR-MPS may supplement or replace other instrumental analysis methods such as capillary electrophoresis and Sanger sequencing for STR and mitochondrial DNA typing, respectively. PCR-MPS also may enable the expansion of forensic DNA analysis methods to include new marker systems such as single nucleotide polymorphisms (SNPs) and insertion/deletions (indels) that currently are assayable using various instrumental analysis methods including microarray and quantitative PCR. Acceptance of PCR-MPS as a forensic method will depend in part upon developing protocols and criteria that define the limitations of a method, including a defensible analytical threshold or method detection limit. This paper describes an approach to establish objective analytical thresholds suitable for multiplexed PCR-MPS methods. A definition is proposed for PCR-MPS method background noise, and an analytical threshold based on background noise is described.

  15. Developmental Validation of Short Tandem Repeat Reagent Kit for Forensic DNA Profiling of Canine Biological Materials

    PubMed Central

    Dayton, Melody; Koskinen, Mikko T; Tom, Bradley K; Mattila, Anna-Maria; Johnston, Eric; Halverson, Joy; Fantin, Dennis; DeNise, Sue; Budowle, Bruce; Smith, David Glenn; Kanthaswamy, Sree

    2009-01-01

    Aim To develop a reagent kit that enables multiplex polymerase chain reaction (PCR) amplification of 18 short tandem repeats (STR) and the canine sex-determining Zinc Finger marker. Methods Validation studies to determine the robustness and reliability in forensic DNA typing of this multiplex assay included sensitivity testing, reproducibility studies, intra- and inter-locus color balance studies, annealing temperature and cycle number studies, peak height ratio determination, characterization of artifacts such as stutter percentages and dye blobs, mixture analyses, species-specificity, case type samples analyses and population studies. Results The kit robustly amplified domesticated dog samples and consistently generated full 19-locus profiles from as little as 125 pg of dog DNA. In addition, wolf DNA samples could be analyzed with the kit. Conclusion The kit, which produces robust, reliable, and reproducible results, will be made available for the forensic research community after modifications based on this study’s evaluation to comply with the quality standards expected for forensic casework. PMID:19480022

  16. SE33 locus as a reliable genetic marker for forensic DNA analysis systems

    PubMed

    Bhinder, Munir Ahmad; Zahoor, Muhammad Yasir; Sadia, Haleema; Qasim, Muhammad; Perveen, Rukhsana; Anjum, Ghulam Murtaza; Iqbal, Muhammad; Ullah, Najeeb; Shehzad, Wasim; Tariq, Muhammad; Waryah, Ali Muhammad

    2018-06-14

    Background/aim: Genetic variation, an authentic tool of individual discrimination, is being used for forensic investigations worldwide. A missing result for even one out of 13-17 markers leads to an inconclusive report. Additional reliable markers are required to compensate such deficiencies. The SE33 locus has high genetic variability in different populations and is being used in forensic investigation systems in some countries. The purpose of the study was to assess the viability of use of the SE33 locus as a supportive marker for forensic DNA profiling. Materials and methods: Amplification of the SE33 locus was performed using the PowerPlex ES Monoplex System SE33 (Promega). After genotyping 204 Pakistani individuals, different genetic and forensic parameters for the SE33 locus were studied. Results: Genotyping of the SE33 locus revealed a total of 43 alleles including 3 novel alleles. Significant values of different forensic and genetic parameters including power of discrimination, power of exclusion, and polymorphism information content were observed. Conclusions: Addition of the SE33 locus in forensic DNA profiling may help to produce conclusive reports where results are inconclusive due to degraded evidence samples. The SE33 locus can confidently be used for Pakistani and neighboring populations having common ancestors from Iran to Central Asia, the Middle East, India and Turkey.

  17. Forensic dentistry in human identification: A review of the literature.

    PubMed

    Ata-Ali, Javier; Ata-Ali, Fadi

    2014-04-01

    An update is provided of the literature on the role of odontology in human identification, based on a PubMed-Medline search of the last 5 years and using the terms: "forensic dentistry" (n = 464 articles), "forensic odontology" (n = 141 articles) and "forensic dentistry identification" (n = 169 articles). Apart from these initial 774 articles, others considered to be important and which were generated by a manual search and cited as references in review articles were also included. Forensic dentistry requires interdisciplinary knowledge, since the data obtained from the oral cavity can contribute to identify an individual or provide information needed in a legal process. Furthermore, the data obtained from the oral cavity can narrow the search range of an individual and play a key role in the victim identification process following mass disasters or catastrophes. This literature search covering the last 5 years describes the novelties referred to buccodental studies in comparative identification, buccodental evaluation in reconstructive identification, human bites as a method for identifying the aggressor, and the role of DNA in dental identification. The oral cavity is a rich and noninvasive source of DNA, and can be used to solve problems of a social, economic or legal nature. Key words:Forensic identification, DNA, forensic dentistry, rugoscopy, cheiloscopy, saliva.

  18. Forensic dentistry in human identification: A review of the literature

    PubMed Central

    Ata-Ali, Fadi

    2014-01-01

    An update is provided of the literature on the role of odontology in human identification, based on a PubMed-Medline search of the last 5 years and using the terms: “forensic dentistry” (n = 464 articles), “forensic odontology” (n = 141 articles) and “forensic dentistry identification” (n = 169 articles). Apart from these initial 774 articles, others considered to be important and which were generated by a manual search and cited as references in review articles were also included. Forensic dentistry requires interdisciplinary knowledge, since the data obtained from the oral cavity can contribute to identify an individual or provide information needed in a legal process. Furthermore, the data obtained from the oral cavity can narrow the search range of an individual and play a key role in the victim identification process following mass disasters or catastrophes. This literature search covering the last 5 years describes the novelties referred to buccodental studies in comparative identification, buccodental evaluation in reconstructive identification, human bites as a method for identifying the aggressor, and the role of DNA in dental identification. The oral cavity is a rich and noninvasive source of DNA, and can be used to solve problems of a social, economic or legal nature. Key words:Forensic identification, DNA, forensic dentistry, rugoscopy, cheiloscopy, saliva. PMID:24790717

  19. The "Starch Wars" and the Early History of DNA Profiling.

    PubMed

    Aronson, J D

    2006-01-01

    Just as the movie Star Wars had a prequel, so did the "DNA Wars"-the series of legal, scientific, and personal battles that took place over the admissibility of forensic DNA evidence from 1989 to 1994. Between the late 1970s and the mid-1980s, another forensic identification technique became mired in controversy: electrophoresis-based blood protein analysis. Although the debates over blood analysis were every bit as rancorous and frustrating to almost everybody involved - so much so that they became known as the "Starch Wars" - their importance has not been adequately appreciated in the recent history of forensic science. After reviewing the early history of blood typing, I will describe the development of the Multi-System approach to blood protein analysis that took place in California from 1977 to 1978. I will then elucidate the history of the Starch Wars, and demonstrate the ways that they shaped subsequent disputes over DNA evidence, especially in California. I will show that: (a) many of the forensic scientists, law enforcement officials, and lawyers who became prominent players in the DNA Wars were deeply involved in the court cases involving protein electrophoresis; and (b) many of the issues that became controversial in the disputes over DNA evidence first emerged in the Starch Wars. In the conclusion, I will suggest various ways to improve the quality of forensic science based on my analysis of the Starch Wars. Copyright © 2006 Central Police University.

  20. Authentication of forensic DNA samples.

    PubMed

    Frumkin, Dan; Wasserstrom, Adam; Davidson, Ariane; Grafit, Arnon

    2010-02-01

    Over the past twenty years, DNA analysis has revolutionized forensic science, and has become a dominant tool in law enforcement. Today, DNA evidence is key to the conviction or exoneration of suspects of various types of crime, from theft to rape and murder. However, the disturbing possibility that DNA evidence can be faked has been overlooked. It turns out that standard molecular biology techniques such as PCR, molecular cloning, and recently developed whole genome amplification (WGA), enable anyone with basic equipment and know-how to produce practically unlimited amounts of in vitro synthesized (artificial) DNA with any desired genetic profile. This artificial DNA can then be applied to surfaces of objects or incorporated into genuine human tissues and planted in crime scenes. Here we show that the current forensic procedure fails to distinguish between such samples of blood, saliva, and touched surfaces with artificial DNA, and corresponding samples with in vivo generated (natural) DNA. Furthermore, genotyping of both artificial and natural samples with Profiler Plus((R)) yielded full profiles with no anomalies. In order to effectively deal with this problem, we developed an authentication assay, which distinguishes between natural and artificial DNA based on methylation analysis of a set of genomic loci: in natural DNA, some loci are methylated and others are unmethylated, while in artificial DNA all loci are unmethylated. The assay was tested on natural and artificial samples of blood, saliva, and touched surfaces, with complete success. Adopting an authentication assay for casework samples as part of the forensic procedure is necessary for maintaining the high credibility of DNA evidence in the judiciary system.

  1. Haplotype data for 23 Y-chromosome markers in a reference sample from Bosnia and Herzegovina

    PubMed Central

    Kovačević, Lejla; Fatur-Cerić, Vera; Hadžić, Negra; Čakar, Jasmina; Primorac, Dragan; Marjanović, Damir

    2013-01-01

    Aim To detect polymorphisms of 23 Y-chromosomal short tandem repeat (STR) loci, including 6 new loci, in a reference database of male population of Bosnia and Herzegovina, as well as to assess the importance of increasing the number of Y-STR loci utilized in forensic DNA analysis. Methods The reference sample consisted of 100 healthy, unrelated men originating from Bosnia and Herzegovina. Sample collection using buccal swabs was performed in all geographical regions of Bosnia and Herzegovina in the period from 2010 to 2011. DNA samples were typed for 23 Y STR loci, including 6 new loci: DYS576, DYS481, DYS549, DYS533, DYS570, and DYS643, which are included in the new PowerPlex® Y 23 amplification kit. Results The absolute frequency of generated haplotypes was calculated and results showed that 98 samples had unique Y 23 haplotypes, and that only two samples shared the same haplotype. The most polymorphic locus was DYS418, with 14 detected alleles and the least polymorphic loci were DYS389I, DYS391, DYS437, and DYS393. Conclusion This study showed that by increasing the number of highly polymorphic Y STR markers, to include those tested in our analysis, leads to a reduction of repeating haplotypes, which is very important in the application of forensic DNA analysis. PMID:23771760

  2. The UK National DNA Database: Implementation of the Protection of Freedoms Act 2012.

    PubMed

    Amankwaa, Aaron Opoku; McCartney, Carole

    2018-03-01

    In 2008, the European Court of Human Rights, in S and Marper v the United Kingdom, ruled that a retention regime that permits the indefinite retention of DNA records of both convicted and non-convicted ("innocent") individuals is disproportionate. The court noted that there was inadequate evidence to justify the retention of DNA records of the innocent. Since the Marper ruling, the laws governing the taking, use, and retention of forensic DNA in England and Wales have changed with the enactment of the Protection of Freedoms Act 2012 (PoFA). This Act, put briefly, permits the indefinite retention of DNA profiles of most convicted individuals and temporal retention for some first-time convicted minors and innocent individuals on the National DNA Database (NDNAD). The PoFA regime was implemented in October 2013. This paper examines ten post-implementation reports of the NDNAD Strategy Board (3), the NDNAD Ethics Group (3) and the Office of the Biometrics Commissioner (OBC) (4). Overall, the reports highlight a considerable improvement in the performance of the database, with a current match rate of 63.3%. Further, the new regime has strengthened the genetic privacy protection of UK citizens. The OBC reports detail implementation challenges ranging from technical, legal and procedural issues to sufficient understanding of the requirements of PoFA by police forces. Risks highlighted in these reports include the deletion of some "retainable" profiles, which could potentially lead to future crimes going undetected. A further risk is the illegal retention of some profiles from innocent individuals, which may lead to privacy issues and legal challenges. In conclusion, the PoFA regime appears to be working well, however, critical research is still needed to evaluate its overall efficacy compared to other retention regimes. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Electrostatic sampling of trace DNA from clothing.

    PubMed

    Zieger, Martin; Defaux, Priscille Merciani; Utz, Silvia

    2016-05-01

    During acts of physical aggression, offenders frequently come into contact with clothes of the victim, thereby leaving traces of DNA-bearing biological material on the garments. Since tape-lifting and swabbing, the currently established methods for non-destructive trace DNA sampling from clothing, both have their shortcomings in collection efficiency and handling, we thought about a new collection method for these challenging samples. Testing two readily available electrostatic devices for their potential to sample biological material from garments made of different fabrics, we found one of them, the electrostatic dust print lifter (DPL), to perform comparable to well-established sampling with wet cotton swabs. In simulated aggression scenarios, we had the same success rate for the establishment of single aggressor profiles, suitable for database submission, with both the DPL and wet swabbing. However, we lost a substantial amount of information with electrostatic sampling, since almost no mixed aggressor-victim profiles suitable for database entry could be established, compared to conventional swabbing. This study serves as a proof of principle for electrostatic DNA sampling from items of clothing. The technique still requires optimization before it might be used in real casework. But we are confident that in the future it could be an efficient and convenient contribution to the toolbox of forensic practitioners.

  4. Epigenetic discrimination of identical twins from blood under the forensic scenario.

    PubMed

    Vidaki, Athina; Díez López, Celia; Carnero-Montoro, Elena; Ralf, Arwin; Ward, Kirsten; Spector, Timothy; Bell, Jordana T; Kayser, Manfred

    2017-11-01

    Monozygotic (MZ) twins share the same STR profile, demonstrating a practical problem in forensic casework. DNA methylation has provided a suitable resource for MZ twin differentiation; however, studies addressing the forensic feasibility are lacking. Here, we investigated epigenetic MZ twin differentiation from blood under the forensic scenario comprising i) the discovery of candidate markers in reference-type blood DNA via genome-wide analysis, ii) the technical validation of candidate markers in reference-type blood DNA using a suitable targeted method, and iii) the analysis of the validated markers in trace-type DNA. Genome-wide methylation analysis in blood DNA from 10 MZ twin pairs resulted in 19-111 twin-differentially methylated sites (tDMSs) per pair with >0.3 twin-to-twin differences. Considering all top three candidate tDMSs across all pairs in the technical validation based on methylation-specific qPCR, 67.85% generated >0.1 twin-to-twin differences. Of the validated tDMSs, 68.4% showed >0.1 twin-to-twin differences with qPCR in trace-type DNA across 8 pairs. Using an updated marker selection strategy, 8 additional candidate tDMSs were obtained for an example MZ pair, of which 7 showed >0.1 twin-to-twin differences in both reference- and trace-type DNA. Lastly, we introduce a high-resolution melting curve analysis of the entire fragment that can complement the proposed approach. Overall, our study demonstrates the general feasibility of epigenetic twin differentiation in the forensic context and highlights that the number of informative tDMSs in the final trace DNA analysis is crucial, as some candidate markers identified in reference DNA were shown not informative in the trace DNA due to various, including technical, reasons. Future studies will need to address the optimal number of epigenetic markers required for reliable identification of MZ twin individuals including statistical considerations. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Assessment of the role of DNA repair in damaged forensic samples.

    PubMed

    Ambers, Angie; Turnbough, Meredith; Benjamin, Robert; King, Jonathan; Budowle, Bruce

    2014-11-01

    Previous studies on DNA damage and repair have involved in vitro laboratory procedures that induce a single type of lesion in naked templates. Although repair of singular, sequestered types of DNA damage has shown some success, forensic and ancient specimens likely contain a number of different types of lesions. This study sought to (1) develop protocols to damage DNA in its native state, (2) generate a pool of candidate samples for repair that more likely emulate authentic forensic samples, and (3) assess the ability of the PreCR(TM) Repair Mix to repair the resultant lesions. Complexed, native DNA is more difficult to damage than naked DNA. Modified procedures included the use of higher concentrations and longer exposure times. Three types of samples, those that demonstrated damage based on short tandem repeat (STR) profile signals, were selected for repair experiments: environmentally damaged bloodstains, bleach-damaged whole blood, and human skeletal remains. Results showed trends of improved performance of STR profiling of bleach-damaged DNA. However, the repair assay did not improve DNA profiles from environmentally damaged bloodstains or bone, and in some cases resulted in lower RFU values for STR alleles. The extensive spectrum of DNA damage and myriad combinations of lesions that can be present in forensic samples appears to pose a challenge for the in vitro PreCR(TM) assay. The data suggest that the use of PreCR in casework should be considered with caution due to the assay's varied results.

  6. Field-based detection of biological samples for forensic analysis: Established techniques, novel tools, and future innovations.

    PubMed

    Morrison, Jack; Watts, Giles; Hobbs, Glyn; Dawnay, Nick

    2018-04-01

    Field based forensic tests commonly provide information on the presence and identity of biological stains and can also support the identification of species. Such information can support downstream processing of forensic samples and generate rapid intelligence. These approaches have traditionally used chemical and immunological techniques to elicit the result but some are known to suffer from a lack of specificity and sensitivity. The last 10 years has seen the development of field-based genetic profiling systems, with specific focus on moving the mainstay of forensic genetic analysis, namely STR profiling, out of the laboratory and into the hands of the non-laboratory user. In doing so it is now possible for enforcement officers to generate a crime scene DNA profile which can then be matched to a reference or database profile. The introduction of these novel genetic platforms also allows for further development of new molecular assays aimed at answering the more traditional questions relating to body fluid identity and species detection. The current drive for field-based molecular tools is in response to the needs of the criminal justice system and enforcement agencies, and promises a step-change in how forensic evidence is processed. However, the adoption of such systems by the law enforcement community does not represent a new strategy in the way forensic science has integrated previous novel approaches. Nor do they automatically represent a threat to the quality control and assurance practices that are central to the field. This review examines the historical need and subsequent research and developmental breakthroughs in field-based forensic analysis over the past two decades with particular focus on genetic methods Emerging technologies from a range of scientific fields that have potential applications in forensic analysis at the crime scene are identified and associated issues that arise from the shift from laboratory into operational field use are discussed. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Forensic Science in Support of Wildlife Conservation Efforts - Genetic Approaches (Global Trends).

    PubMed

    Linacre, A

    2011-01-01

    Wildlife forensic science is a relatively recent development to meet the increasing need of the criminal justice system where there are investigations in alleged transgressions of either international or national legislation. This application of science draws on conservation genetics and forensic geneticists from mainstream forensic science. This review is a broad overview of the history of forensic wildlife science and some of the recent developments in forensic wildlife genetics with the application of DNA developments to nonhuman samples encountered in a forensic science investigation. The review will move from methods to look at the entire genome, when there is no previous knowledge of the species studied, through methods of species identification, using DNA to determine a possible geographic origin, through to assigning samples to a particular individual or a close genetic relative of this individual. The transfer of research methods into the criminal justice system for the investigation of wildlife crimes has been largely successful as is illustrated in the review. The review concludes with comments on the need for standardization and regulation in wildlife forensic science. Copyright © 2011 Central Police University.

  8. Automated extraction of DNA from biological stains on fabric from crime cases. A comparison of a manual and three automated methods.

    PubMed

    Stangegaard, Michael; Hjort, Benjamin B; Hansen, Thomas N; Hoflund, Anders; Mogensen, Helle S; Hansen, Anders J; Morling, Niels

    2013-05-01

    The presence of PCR inhibitors in extracted DNA may interfere with the subsequent quantification and short tandem repeat (STR) reactions used in forensic genetic DNA typing. DNA extraction from fabric for forensic genetic purposes may be challenging due to the occasional presence of PCR inhibitors that may be co-extracted with the DNA. Using 120 forensic trace evidence samples consisting of various types of fabric, we compared three automated DNA extraction methods based on magnetic beads (PrepFiler Express Forensic DNA Extraction Kit on an AutoMate Express, QIAsyphony DNA Investigator kit either with the sample pre-treatment recommended by Qiagen or an in-house optimized sample pre-treatment on a QIAsymphony SP) and one manual method (Chelex) with the aim of reducing the amount of PCR inhibitors in the DNA extracts and increasing the proportion of reportable STR-profiles. A total of 480 samples were processed. The highest DNA recovery was obtained with the PrepFiler Express kit on an AutoMate Express while the lowest DNA recovery was obtained using a QIAsymphony SP with the sample pre-treatment recommended by Qiagen. Extraction using a QIAsymphony SP with the sample pre-treatment recommended by Qiagen resulted in the lowest percentage of PCR inhibition (0%) while extraction using manual Chelex resulted in the highest percentage of PCR inhibition (51%). The largest number of reportable STR-profiles was obtained with DNA from samples extracted with the PrepFiler Express kit (75%) while the lowest number was obtained with DNA from samples extracted using a QIAsymphony SP with the sample pre-treatment recommended by Qiagen (41%). Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Isolation of Mitochondrial DNA from Single, Short Hairs without Roots Using Pressure Cycling Technology.

    PubMed

    Harper, Kathryn A; Meiklejohn, Kelly A; Merritt, Richard T; Walker, Jessica; Fisher, Constance L; Robertson, James M

    2018-02-01

    Hairs are commonly submitted as evidence to forensic laboratories, but standard nuclear DNA analysis is not always possible. Mitochondria (mt) provide another source of genetic material; however, manual isolation is laborious. In a proof-of-concept study, we assessed pressure cycling technology (PCT; an automated approach that subjects samples to varying cycles of high and low pressure) for extracting mtDNA from single, short hairs without roots. Using three microscopically similar donors, we determined the ideal PCT conditions and compared those yields to those obtained using the traditional manual micro-tissue grinder method. Higher yields were recovered from grinder extracts, but yields from PCT extracts exceeded the requirements for forensic analysis, with the DNA quality confirmed through sequencing. Automated extraction of mtDNA from hairs without roots using PCT could be useful for forensic laboratories processing numerous samples.

  10. AQME: A forensic mitochondrial DNA analysis tool for next-generation sequencing data.

    PubMed

    Sturk-Andreaggi, Kimberly; Peck, Michelle A; Boysen, Cecilie; Dekker, Patrick; McMahon, Timothy P; Marshall, Charla K

    2017-11-01

    The feasibility of generating mitochondrial DNA (mtDNA) data has expanded considerably with the advent of next-generation sequencing (NGS), specifically in the generation of entire mtDNA genome (mitogenome) sequences. However, the analysis of these data has emerged as the greatest challenge to implementation in forensics. To address this need, a custom toolkit for use in the CLC Genomics Workbench (QIAGEN, Hilden, Germany) was developed through a collaborative effort between the Armed Forces Medical Examiner System - Armed Forces DNA Identification Laboratory (AFMES-AFDIL) and QIAGEN Bioinformatics. The AFDIL-QIAGEN mtDNA Expert, or AQME, generates an editable mtDNA profile that employs forensic conventions and includes the interpretation range required for mtDNA data reporting. AQME also integrates an mtDNA haplogroup estimate into the analysis workflow, which provides the analyst with phylogenetic nomenclature guidance and a profile quality check without the use of an external tool. Supplemental AQME outputs such as nucleotide-per-position metrics, configurable export files, and an audit trail are produced to assist the analyst during review. AQME is applied to standard CLC outputs and thus can be incorporated into any mtDNA bioinformatics pipeline within CLC regardless of sample type, library preparation or NGS platform. An evaluation of AQME was performed to demonstrate its functionality and reliability for the analysis of mitogenome NGS data. The study analyzed Illumina mitogenome data from 21 samples (including associated controls) of varying quality and sample preparations with the AQME toolkit. A total of 211 tool edits were automatically applied to 130 of the 698 total variants reported in an effort to adhere to forensic nomenclature. Although additional manual edits were required for three samples, supplemental tools such as mtDNA haplogroup estimation assisted in identifying and guiding these necessary modifications to the AQME-generated profile. Along with profile generation, AQME reported accurate haplogroups for 18 of the 19 samples analyzed. The single errant haplogroup assignment, although phylogenetically close, identified a bug that only affects partial mitogenome data. Future adjustments to AQME's haplogrouping tool will address this bug as well as enhance the overall scoring strategy to better refine and automate haplogroup assignments. As NGS enables broader use of the mtDNA locus in forensics, the availability of AQME and other forensic-focused mtDNA analysis tools will ease the transition and further support mitogenome analysis within routine casework. Toward this end, the AFMES-AFDIL has utilized the AQME toolbox in conjunction with the CLC Genomics Workbench to successfully validate and implement two NGS mitogenome methods. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Differential reporting of mixed DNA profiles and its impact on jurists' evaluation of evidence. An international analysis.

    PubMed

    de Keijser, Jan W; Malsch, Marijke; Luining, Egge T; Weulen Kranenbarg, Marleen; Lenssen, Dominique J H M

    2016-07-01

    While DNA analysis is considered by many the gold standard in forensic science, there is ample room for variation in interpretation and reporting. This seems especially the case when working with (complex) mixed DNA profiles. Two consecutive studies on differential DNA reporting were conducted. In Study 1, we first examined type and magnitude of differences when forensic DNA experts across institutes and jurisdictions are handed an identical forensic case with mixed profiles. In Study 2, we explore the impact of the observed differential reporting on jurists' evaluation of the DNA evidence. 19 DNA expert reports from forensic institutes across Western jurisdictions were obtained. Differences between the reports were many and include extensiveness of the reports, explanations of technical issues, use of explanatory appendices, level of reporting, use of context information, and, most markedly, type and substantive content of the conclusions. In Study 2, a group of criminal law students judged a selection of these reports in a quasi experimental study design. Findings show that these differing reports have quite different evidentiary value for jurists, depending on which expert authored the report. It is argued that the impact of differential reporting on jurists' evaluation was so fundamental and substantive that it is seems reasonable to claim that in an actual court case it could make the difference between acquittal and conviction. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Enhanced genetic analysis of single human bioparticles recovered by simplified micromanipulation from forensic 'touch DNA' evidence.

    PubMed

    Farash, Katherine; Hanson, Erin K; Ballantyne, Jack

    2015-03-09

    DNA profiles can be obtained from 'touch DNA' evidence, which comprises microscopic traces of human biological material. Current methods for the recovery of trace DNA employ cotton swabs or adhesive tape to sample an area of interest. However, such a 'blind-swabbing' approach will co-sample cellular material from the different individuals, even if the individuals' cells are located in geographically distinct locations on the item. Thus, some of the DNA mixtures encountered in touch DNA samples are artificially created by the swabbing itself. In some instances, a victim's DNA may be found in significant excess thus masking any potential perpetrator's DNA. In order to circumvent the challenges with standard recovery and analysis methods, we have developed a lower cost, 'smart analysis' method that results in enhanced genetic analysis of touch DNA evidence. We describe an optimized and efficient micromanipulation recovery strategy for the collection of bio-particles present in touch DNA samples, as well as an enhanced amplification strategy involving a one-step 5 µl microvolume lysis/STR amplification to permit the recovery of STR profiles from the bio-particle donor(s). The use of individual or few (i.e., "clumps") bioparticles results in the ability to obtain single source profiles. These procedures represent alternative enhanced techniques for the isolation and analysis of single bioparticles from forensic touch DNA evidence. While not necessary in every forensic investigation, the method could be highly beneficial for the recovery of a single source perpetrator DNA profile in cases involving physical assault (e.g., strangulation) that may not be possible using standard analysis techniques. Additionally, the strategies developed here offer an opportunity to obtain genetic information at the single cell level from a variety of other non-forensic trace biological material.

  13. Identification of forensic samples by using an infrared-based automatic DNA sequencer.

    PubMed

    Ricci, Ugo; Sani, Ilaria; Klintschar, Michael; Cerri, Nicoletta; De Ferrari, Francesco; Giovannucci Uzielli, Maria Luisa

    2003-06-01

    We have recently introduced a new protocol for analyzing all core loci of the Federal Bureau of Investigation's (FBI) Combined DNA Index System (CODIS) with an infrared (IR) automatic DNA sequencer (LI-COR 4200). The amplicons were labeled with forward oligonucleotide primers, covalently linked to a new infrared fluorescent molecule (IRDye 800). The alleles were displayed as familiar autoradiogram-like images with real-time detection. This protocol was employed for paternity testing, population studies, and identification of degraded forensic samples. We extensively analyzed some simulated forensic samples and mixed stains (blood, semen, saliva, bones, and fixed archival embedded tissues), comparing the results with donor samples. Sensitivity studies were also performed for the four multiplex systems. Our results show the efficiency, reliability, and accuracy of the IR system for the analysis of forensic samples. We also compared the efficiency of the multiplex protocol with ultraviolet (UV) technology. Paternity tests, undegraded DNA samples, and real forensic samples were analyzed with this approach based on IR technology and with UV-based automatic sequencers in combination with commercially-available kits. The comparability of the results with the widespread UV methods suggests that it is possible to exchange data between laboratories using the same core group of markers but different primer sets and detection methods.

  14. NCSTL

    Science.gov Websites

    It's Evident EDUCATION & TRAINING CALENDAR SEARCH FORENSIC DATABASE Forensic Database The NCSTL.org can be found in the Training and Education section of the NCSTL website. The on-demand webinar is free fresh tips in the 2003 case. The Snapshot analysis service — developed by Virginia-based Parabon Â

  15. Population-specific FST values for forensic STR markers: A worldwide survey.

    PubMed

    Buckleton, John; Curran, James; Goudet, Jérôme; Taylor, Duncan; Thiery, Alexandre; Weir, B S

    2016-07-01

    The interpretation of matching between DNA profiles of a person of interest and an item of evidence is undertaken using population genetic models to predict the probability of matching by chance. Calculation of matching probabilities is straightforward if allelic probabilities are known, or can be estimated, in the relevant population. It is more often the case, however, that the relevant population has not been sampled and allele frequencies are available only from a broader collection of populations as might be represented in a national or regional database. Variation of allele probabilities among the relevant populations is quantified by the population structure quantity FST and this quantity affects matching proportions. Matching within a population can be interpreted only with respect to matching between populations and we show here that FST, can be estimated from sample allelic matching proportions within and between populations. We report such estimates from data we extracted from 250 papers in the forensic literature, representing STR profiles at up to 24 loci from nearly 500,000 people in 446 different populations. The results suggest that theta values in current forensic use do not have the buffer of conservatism often thought. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  16. Population-specific FST values for forensic STR markers: A worldwide survey

    PubMed Central

    Buckleton, John; Curran, James; Goudet, Jérôme; Taylor, Duncan; Thiery, Alexandre; Weir, B.S.

    2016-01-01

    The interpretation of matching between DNA profiles of a person of interest and an item of evidence is undertaken using population genetic models to predict the probability of matching by chance. Calculation of matching probabilities is straightforward if allelic probabilities are known, or can be estimated, in the relevant population. It is more often the case, however, that the relevant population has not been sampled and allele frequencies are available only from a broader collection of populations as might be represented in a national or regional database. Variation of allele probabilities among the relevant populations is quantified by the population structure quantity FST and this quanity affects matching propoptions. Matching within a population can be interpreted only with respect to matching between populations and we show here that FST, can be estimated from sample allelic matching proportions within and between populations. We report such estimates from data we extracted from 250 papers in the forensic literature, representing STR profiles at up to 24 loci from nearly 500,000 people in 446 different populations. The results suggest that theta values in current forensic use do not have the buffer of conservativism often thought. PMID:27082756

  17. Evaluation of next generation mtGenome sequencing using the Ion Torrent Personal Genome Machine (PGM)☆

    PubMed Central

    Parson, Walther; Strobl, Christina; Huber, Gabriela; Zimmermann, Bettina; Gomes, Sibylle M.; Souto, Luis; Fendt, Liane; Delport, Rhena; Langit, Reina; Wootton, Sharon; Lagacé, Robert; Irwin, Jodi

    2013-01-01

    Insights into the human mitochondrial phylogeny have been primarily achieved by sequencing full mitochondrial genomes (mtGenomes). In forensic genetics (partial) mtGenome information can be used to assign haplotypes to their phylogenetic backgrounds, which may, in turn, have characteristic geographic distributions that would offer useful information in a forensic case. In addition and perhaps even more relevant in the forensic context, haplogroup-specific patterns of mutations form the basis for quality control of mtDNA sequences. The current method for establishing (partial) mtDNA haplotypes is Sanger-type sequencing (STS), which is laborious, time-consuming, and expensive. With the emergence of Next Generation Sequencing (NGS) technologies, the body of available mtDNA data can potentially be extended much more quickly and cost-efficiently. Customized chemistries, laboratory workflows and data analysis packages could support the community and increase the utility of mtDNA analysis in forensics. We have evaluated the performance of mtGenome sequencing using the Personal Genome Machine (PGM) and compared the resulting haplotypes directly with conventional Sanger-type sequencing. A total of 64 mtGenomes (>1 million bases) were established that yielded high concordance with the corresponding STS haplotypes (<0.02% differences). About two-thirds of the differences were observed in or around homopolymeric sequence stretches. In addition, the sequence alignment algorithm employed to align NGS reads played a significant role in the analysis of the data and the resulting mtDNA haplotypes. Further development of alignment software would be desirable to facilitate the application of NGS in mtDNA forensic genetics. PMID:23948325

  18. Current developments in forensic interpretation of mixed DNA samples (Review).

    PubMed

    Hu, Na; Cong, Bin; Li, Shujin; Ma, Chunling; Fu, Lihong; Zhang, Xiaojing

    2014-05-01

    A number of recent improvements have provided contemporary forensic investigations with a variety of tools to improve the analysis of mixed DNA samples in criminal investigations, producing notable improvements in the analysis of complex trace samples in cases of sexual assult and homicide. Mixed DNA contains DNA from two or more contributors, compounding DNA analysis by combining DNA from one or more major contributors with small amounts of DNA from potentially numerous minor contributors. These samples are characterized by a high probability of drop-out or drop-in combined with elevated stutter, significantly increasing analysis complexity. At some loci, minor contributor alleles may be completely obscured due to amplification bias or over-amplification, creating the illusion of additional contributors. Thus, estimating the number of contributors and separating contributor genotypes at a given locus is significantly more difficult in mixed DNA samples, requiring the application of specialized protocols that have only recently been widely commercialized and standardized. Over the last decade, the accuracy and repeatability of mixed DNA analyses available to conventional forensic laboratories has greatly advanced in terms of laboratory technology, mathematical models and biostatistical software, generating more accurate, rapid and readily available data for legal proceedings and criminal cases.

  19. Current developments in forensic interpretation of mixed DNA samples (Review)

    PubMed Central

    HU, NA; CONG, BIN; LI, SHUJIN; MA, CHUNLING; FU, LIHONG; ZHANG, XIAOJING

    2014-01-01

    A number of recent improvements have provided contemporary forensic investigations with a variety of tools to improve the analysis of mixed DNA samples in criminal investigations, producing notable improvements in the analysis of complex trace samples in cases of sexual assult and homicide. Mixed DNA contains DNA from two or more contributors, compounding DNA analysis by combining DNA from one or more major contributors with small amounts of DNA from potentially numerous minor contributors. These samples are characterized by a high probability of drop-out or drop-in combined with elevated stutter, significantly increasing analysis complexity. At some loci, minor contributor alleles may be completely obscured due to amplification bias or over-amplification, creating the illusion of additional contributors. Thus, estimating the number of contributors and separating contributor genotypes at a given locus is significantly more difficult in mixed DNA samples, requiring the application of specialized protocols that have only recently been widely commercialized and standardized. Over the last decade, the accuracy and repeatability of mixed DNA analyses available to conventional forensic laboratories has greatly advanced in terms of laboratory technology, mathematical models and biostatistical software, generating more accurate, rapid and readily available data for legal proceedings and criminal cases. PMID:24748965

  20. An optimized procedure for obtaining DNA from fired and unfired ammunition.

    PubMed

    Montpetit, Shawn; O'Donnell, Patrick

    2015-07-01

    Gun crimes are a significant problem facing law enforcement agencies. Traditional forensic examination of firearms involves comparisons of markings imparted to bullets and cartridge casings during the firing process. DNA testing of casings and cartridges may not be routinely done in crime laboratories due a variety of factors including the typically low amounts of DNA recovered. The San Diego Police Department (SDPD) Crime Laboratory conducted a study to optimize the collection and profiling of DNA from fired and unfired ammunition. The method was optimized to where interpretable DNA results were obtained for 26.1% of the total number of forensic casework evidence samples, and provided some insights into the level of secondary transfer that might be expected from this type of evidence. Briefly detailed are the results from the experimental study and the forensic casework analysis using the optimized process. Mixtures (samples having more DNA types than the loader's known genotype detected or visible at any marker) were obtained in 39.8% of research samples and the likely source of DNA mixtures is discussed. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  1. Defense Biometric and Forensic Office Research, Development, Test and Evaluation Strategy

    DTIC Science & Technology

    2015-01-06

    investments in biometric and forensic RDT&E. From refining biometric modalities to exploring ‘ game changing’ forensic technologies such as rapid DNA to the... ASD (R&E)), is to identify, fund, manage and transition projects that support biometric and/or forensic requirements. In the second role, the DBFO...forensic stakeholders cannot fund, to the COIs for consideration.  Increase contacts with ASD (R&E) divisions/laboratories focused on basic research

  2. Developmental validation of a custom panel including 273 SNPs for forensic application using Ion Torrent PGM.

    PubMed

    Zhang, Suhua; Bian, Yingnan; Chen, Anqi; Zheng, Hancheng; Gao, Yuzhen; Hou, Yiping; Li, Chengtao

    2017-03-01

    Utilizing massively parallel sequencing (MPS) technology for SNP testing in forensic genetics is becoming attractive because of the shortcomings of STR markers, such as their high mutation rates and disadvantages associated with the current PCR-CE method as well as its limitations regarding multiplex capabilities. MPS offers the potential to genotype hundreds to thousands of SNPs from multiple samples in a single experimental run. In this study, we designed a customized SNP panel that includes 273 forensically relevant identity SNPs chosen from SNPforID, IISNP, and the HapMap database as well as previously related studies and evaluated the levels of genotyping precision, sequence coverage, sensitivity and SNP performance using the Ion Torrent PGM. In a concordant study of the custom MPS-SNP panel, only four MPS callings were missing due to coverage reads that were too low (<20), whereas the others were fully concordant with Sanger's sequencing results across the two control samples, that is, 9947A and 9948. The analyses indicated a balanced coverage among the included loci, with the exception of the 16 SNPs that were used to detect an inconsistent allele balance and/or lower coverage reads among 50 tested individuals from the Chinese HAN population and the above controls. With the exception of the 16 poorly performing SNPs, the sequence coverage obtained was extensive for the bulk of the SNPs, and only three Y-SNPs (rs16980601, rs11096432, rs3900) showed a mean coverage below 1000. Analyses of the dilution series of control DNA 9948 yielded reproducible results down to 1ng of DNA input. In addition, we provide an analysis tool for automated data quality control and genotyping checks, and we conclude that the SNP targets are polymorphic and independent in the Chinese HAN population. In summary, the evaluation of the sensitivity, accuracy and genotyping performance provides strong support for the application of MPS technology in forensic SNP analysis, and the assay offers a straightforward sample-to-genotype workflow that could be beneficial in forensic casework with respect to both individual identification and complex kinship issues. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. Mitochondrial DNA and STR analyses for human DNA from maggots crop contents: a forensic entomology case from central-southern China.

    PubMed

    Li, X; Cai, J F; Guo, Y D; Xiong, F; Zhang, L; Feng, H; Meng, F M; Fu, Y; Li, J B; Chen, Y Q

    2011-08-01

    Insect larvae and adult insects found on human corpses can provide important forensic evidence however it is useful to be able to prove evidence of association. Without this, it could be claimed that the insect evidence was a contaminant or had been planted on the body. This paper describes how mitochondrial DNA (mtDNA) and STR analysis of the crop contents of larvae of the blowfly Aldrichina grahami collected from separated body parts was used to provide evidence of association.

  4. An Improved Forensic Science Information Search.

    PubMed

    Teitelbaum, J

    2015-01-01

    Although thousands of search engines and databases are available online, finding answers to specific forensic science questions can be a challenge even to experienced Internet users. Because there is no central repository for forensic science information, and because of the sheer number of disciplines under the forensic science umbrella, forensic scientists are often unable to locate material that is relevant to their needs. The author contends that using six publicly accessible search engines and databases can produce high-quality search results. The six resources are Google, PubMed, Google Scholar, Google Books, WorldCat, and the National Criminal Justice Reference Service. Carefully selected keywords and keyword combinations, designating a keyword phrase so that the search engine will search on the phrase and not individual keywords, and prompting search engines to retrieve PDF files are among the techniques discussed. Copyright © 2015 Central Police University.

  5. Development and validation of InnoQuant™, a sensitive human DNA quantitation and degradation assessment method for forensic samples using high copy number mobile elements Alu and SVA.

    PubMed

    Pineda, Gina M; Montgomery, Anne H; Thompson, Robyn; Indest, Brooke; Carroll, Marion; Sinha, Sudhir K

    2014-11-01

    There is a constant need in forensic casework laboratories for an improved way to increase the first-pass success rate of forensic samples. The recent advances in mini STR analysis, SNP, and Alu marker systems have now made it possible to analyze highly compromised samples, yet few tools are available that can simultaneously provide an assessment of quantity, inhibition, and degradation in a sample prior to genotyping. Currently there are several different approaches used for fluorescence-based quantification assays which provide a measure of quantity and inhibition. However, a system which can also assess the extent of degradation in a forensic sample will be a useful tool for DNA analysts. Possessing this information prior to genotyping will allow an analyst to more informatively make downstream decisions for the successful typing of a forensic sample without unnecessarily consuming DNA extract. Real-time PCR provides a reliable method for determining the amount and quality of amplifiable DNA in a biological sample. Alu are Short Interspersed Elements (SINE), approximately 300bp insertions which are distributed throughout the human genome in large copy number. The use of an internal primer to amplify a segment of an Alu element allows for human specificity as well as high sensitivity when compared to a single copy target. The advantage of an Alu system is the presence of a large number (>1000) of fixed insertions in every human genome, which minimizes the individual specific variation possible when using a multi-copy target quantification system. This study utilizes two independent retrotransposon genomic targets to obtain quantification of an 80bp "short" DNA fragment and a 207bp "long" DNA fragment in a degraded DNA sample in the multiplex system InnoQuant™. The ratio of the two quantitation values provides a "Degradation Index", or a qualitative measure of a sample's extent of degradation. The Degradation Index was found to be predictive of the observed loss of STR markers and alleles as degradation increases. Use of a synthetic target as an internal positive control (IPC) provides an additional assessment for the presence of PCR inhibitors in the test sample. In conclusion, a DNA based qualitative/quantitative/inhibition assessment system that accurately predicts the status of a biological sample, will be a valuable tool for deciding which DNA test kit to utilize and how much target DNA to use, when processing compromised forensic samples for DNA testing. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. Clinical forensic sample collection techniques following consensual intercourse in volunteers - cervical canal brush compared to conventional swabs.

    PubMed

    Joki-Erkkilä, Minna; Tuomisto, Sari; Seppänen, Mervi; Huhtala, Heini; Ahola, Arja; Rainio, Juha; Karhunen, Pekka J

    2014-10-01

    The purpose of the research was to evaluate gynecological evidence collection techniques; the benefit of cervical canal brush sample compared to vaginal fornix and cervical swab samples and the time frame for detecting Y-chromosomal material QiAmp DNA Mini Kit(®) and Quantifiler Y Human Male DNA Quantification Kit(®) in adult volunteers following consensual intercourse. Eighty-four adult female volunteers following consensual intercourse were recruited for the study. By combining all sample collecting techniques, 81.0% of the volunteers were Y-DNA positive. Up to 60 h the conventional swab sampling techniques detected more Y-DNA positive samples when compared to the brush technique. However, after 60 h, the cervical canal brush sample technique showed its benefit by detecting 27.3% (6/22) of Y-DNA positive samples, which were Y-DNA negative in both conventional swab sampling techniques. By combining swab and brush techniques, 75% of the volunteers were still Y-DNA positive in 72-144 post-coital hours. The rate of measurable Y-DNA decreased approximately 3% per hour. Despite reported consensual intercourse, 6.8% (3/44) of volunteers were Y-DNA negative within 48 h. Y-DNA was not detected after 144 post-coital hours (6 days). In conclusion, the brush as a forensic evidence collection method may provide additional biological trace evidence from the cervical canal, although the best biological trace evidence collection can be obtained by combining all three sampling techniques. The time frame for gynecological forensic evidence sample collection should be considered to be at least a week if sexual violence is suspected. Copyright © 2014 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  7. The validation of forensic DNA extraction systems to utilize soil contaminated biological evidence.

    PubMed

    Kasu, Mohaimin; Shires, Karen

    2015-07-01

    The production of full DNA profiles from biological evidence found in soil has a high failure rate due largely to the inhibitory substance humic acid (HA). Abundant in various natural soils, HA co-extracts with DNA during extraction and inhibits DNA profiling by binding to the molecular components of the genotyping assay. To successfully utilize traces of soil contaminated evidence, such as that found at many murder and rape crime scenes in South Africa, a reliable HA removal extraction system would often be selected based on previous validation studies. However, for many standard forensic DNA extraction systems, peer-reviewed publications detailing the efficacy on soil evidence is either lacking or is incomplete. Consequently, these sample types are often not collected or fail to yield suitable DNA material due to the use of unsuitable methodology. The aim of this study was to validate the common forensic DNA collection and extraction systems used in South Africa, namely DNA IQ, FTA elute and Nucleosave for processing blood and saliva contaminated with HA. A forensic appropriate volume of biological evidence was spiked with HA (0, 0.5, 1.5 and 2.5 mg/ml) and processed through each extraction protocol for the evaluation of HA removal using QPCR and STR-genotyping. The DNA IQ magnetic bead system effectively removed HA from highly contaminated blood and saliva, and generated consistently acceptable STR profiles from both artificially spiked samples and crude soil samples. This system is highly recommended for use on soil-contaminated evidence over the cellulose card-based systems currently being preferentially used for DNA sample collection. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. Automation of DNA and miRNA co-extraction for miRNA-based identification of human body fluids and tissues.

    PubMed

    Kulstein, Galina; Marienfeld, Ralf; Miltner, Erich; Wiegand, Peter

    2016-10-01

    In the last years, microRNA (miRNA) analysis came into focus in the field of forensic genetics. Yet, no standardized and recommendable protocols for co-isolation of miRNA and DNA from forensic relevant samples have been developed so far. Hence, this study evaluated the performance of an automated Maxwell® 16 System-based strategy (Promega) for co-extraction of DNA and miRNA from forensically relevant (blood and saliva) samples compared to (semi-)manual extraction methods. Three procedures were compared on the basis of recovered quantity of DNA and miRNA (as determined by real-time PCR and Bioanalyzer), miRNA profiling (shown by Cq values and extraction efficiency), STR profiles, duration, contamination risk and handling. All in all, the results highlight that the automated co-extraction procedure yielded the highest miRNA and DNA amounts from saliva and blood samples compared to both (semi-)manual protocols. Also, for aged and genuine samples of forensically relevant traces the miRNA and DNA yields were sufficient for subsequent downstream analysis. Furthermore, the strategy allows miRNA extraction only in cases where it is relevant to obtain additional information about the sample type. Besides, this system enables flexible sample throughput and labor-saving sample processing with reduced risk of cross-contamination. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. A potential new diagnostic tool to aid DNA analysis from heat compromised bone using colorimetry: A preliminary study.

    PubMed

    Fredericks, Jamie D; Ringrose, Trevor J; Dicken, Anthony; Williams, Anna; Bennett, Phil

    2015-03-01

    Extracting viable DNA from many forensic sample types can be very challenging, as environmental conditions may be far from optimal with regard to DNA preservation. Consequently, skeletal tissue can often be an invaluable source of DNA. The bone matrix provides a hardened material that encapsulates DNA, acting as a barrier to environmental insults that would otherwise be detrimental to its integrity. However, like all forensic samples, DNA in bone can still become degraded in extreme conditions, such as intense heat. Extracting DNA from bone can be laborious and time-consuming. Thus, a lot of time and money can be wasted processing samples that do not ultimately yield viable DNA. We describe the use of colorimetry as a novel diagnostic tool that can assist DNA analysis from heat-treated bone. This study focuses on characterizing changes in the material and physical properties of heated bone, and their correlation with digitally measured color variation. The results demonstrate that the color of bone, which serves as an indicator of the chemical processes that have occurred, can be correlated with the success or failure of subsequent DNA amplification. Copyright © 2014 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

  10. Digital Forensics

    ERIC Educational Resources Information Center

    Harron, Jason; Langdon, John; Gonzalez, Jennifer; Cater, Scott

    2017-01-01

    The term forensic science may evoke thoughts of blood-spatter analysis, DNA testing, and identifying molds, spores, and larvae. A growing part of this field, however, is that of digital forensics, involving techniques with clear connections to math and physics. This article describes a five-part project involving smartphones and the investigation…

  11. The Potential of Cosmetic Applicators as a Source of DNA for Forensic Analysis.

    PubMed

    Adamowicz, Michael S; Labonte, Renáe D; Schienman, John E

    2015-07-01

    Personal products, such as toothbrushes, have been used as both known reference and evidentiary samples for forensic DNA analysis. This study examined the viability of a broad selection of cosmetic applicators for use as targets for human DNA extraction and short tandem repeat (STR) analysis using standard polymerase chain reaction (PCR) conditions. Applicator types included eyeliner smudgers, pencils and crayons, eye shadow sponges, mascara wands, concealer wands, face makeup sponges, pads and brushes, lipsticks and balms, and lip gloss wands. The quantity and quality of DNA extracted from each type of applicator were examined by assessing the number of loci successfully amplified and the peak balance of the heterozygous alleles in each full STR profile. While degraded DNA, stochastic amplification, and PCR inhibition were observed for some items, full STR profiles were developed for 14 of 76 applicators. The face makeup sponge applicators yielded the highest proportional number of full STR profiles (4/7). © 2015 American Academy of Forensic Sciences.

  12. Calculating the weight of evidence in low-template forensic DNA casework.

    PubMed

    Lohmueller, Kirk E; Rudin, Norah

    2013-01-01

    Interpreting and assessing the weight of low-template DNA evidence presents a formidable challenge in forensic casework. This report describes a case in which a similar mixed DNA profile was obtained from four different bloodstains. The defense proposed that the low-level minor profile came from an alternate suspect, the defendant's mistress. The strength of the evidence was assessed using a probabilistic approach that employed likelihood ratios incorporating the probability of allelic drop-out. Logistic regression was used to model the probability of drop-out using empirical validation data from the government laboratory. The DNA profile obtained from the bloodstain described in this report is at least 47 billion times more likely if, in addition to the victim, the alternate suspect was the minor contributor, than if another unrelated individual was the minor contributor. This case illustrates the utility of the probabilistic approach for interpreting complex low-template DNA profiles. © 2012 American Academy of Forensic Sciences.

  13. [Advances of forensic entomology in China].

    PubMed

    Lan, Ling-mei; Liao, Zhi-gang; Chen, Yao-qing; Yao, Yue; Li, Jian-bo; Li, Mao-yang; Cai, Ji-feng

    2006-12-01

    Forensic entomology is a branch of forensic medicine, which applies studies of insects and arthropods to getting evidence for court and has an analogous advantage in the estimation of the postmortem interval (PMI) and other questions of forensic relevance. The paper expounds its definition and contents and reviews some progress of the studies in some aspects in China such as the constitution and succession of insect community on the different cadavers, the applications of morphological features of insects and the technology of analysis of deoxyribonucleic acid (DNA) in forensic entomology, and forensic entomological toxicology etc.

  14. International forensic automotive paint database

    NASA Astrophysics Data System (ADS)

    Bishea, Gregory A.; Buckle, Joe L.; Ryland, Scott G.

    1999-02-01

    The Technical Working Group for Materials Analysis (TWGMAT) is supporting an international forensic automotive paint database. The Federal Bureau of Investigation and the Royal Canadian Mounted Police (RCMP) are collaborating on this effort through TWGMAT. This paper outlines the support and further development of the RCMP's Automotive Paint Database, `Paint Data Query'. This cooperative agreement augments and supports a current, validated, searchable, automotive paint database that is used to identify make(s), model(s), and year(s) of questioned paint samples in hit-and-run fatalities and other associated investigations involving automotive paint.

  15. Improving efficiency of a small forensic DNA laboratory: validation of robotic assays and evaluation of microcapillary array device.

    PubMed

    Crouse, Cecelia A; Yeung, Stephanie; Greenspoon, Susan; McGuckian, Amy; Sikorsky, Julie; Ban, Jeff; Mathies, Richard

    2005-08-01

    To present validation studies performed for the implementation of existing and new technologies to increase the efficiency in the forensic DNA Section of the Palm Beach County Sheriff's Office (PBSO) Crime Laboratory. Using federally funded grants, internal support, and an external Process Mapping Team, the PBSO collaborated with forensic vendors, universities, and other forensic laboratories to enhance DNA testing procedures, including validation of the DNA IQ magnetic bead extraction system, robotic DNA extraction using the BioMek2000, the ABI7000 Sequence Detection System, and is currently evaluating a micro Capillary Array Electrophoresis device. The PBSO successfully validated and implemented both manual and automated Promega DNA IQ magnetic bead extractions system, which have increased DNA profile results from samples with low DNA template concentrations. The Beckman BioMek2000 DNA robotic workstation has been validated for blood, tissue, bone, hair, epithelial cells (touch evidence), and mixed stains such as semen. There has been a dramatic increase in the number of samples tested per case since implementation of the robotic extraction protocols. The validation of the ABI7000 real-time quantitative polymerase chain reaction (qPCR) technology and the single multiplex short tandem repeat (STR) PowerPlex16 BIO amplification system has provided both a time and a financial benefit. In addition, the qPCR system allows more accurate DNA concentration data and the PowerPlex 16 BIO multiplex generates DNA profiles data in half the time when compared to PowerPlex1.1 and PowerPlex2.1 STR systems. The PBSO's future efficiency requirements are being addressed through collaboration with the University of California at Berkeley and the Virginia Division of Forensic Science to validate microcapillary array electrophoresis instrumentation. Initial data demonstrated the electrophoresis of 96 samples in less than twenty minutes. The PBSO demonstrated, through the validation of more efficient extraction and quantification technology, an increase in the number of evidence samples tested using robotic/DNA IQ magnetic bead DNA extraction, a decrease in the number of negative samples amplified due to qPCR and implementation of a single multiplex amplification system. In addition, initial studies show the microcapillary array electrophoresis device (microCAE) evaluation results provide greater sensitivity and faster STR analysis output than current platforms.

  16. The Effectiveness of Trace DNA Profiling-A Comparison Between a U.S. and a U.K. Law Enforcement Jurisdiction.

    PubMed

    Bond, John W; Weart, Jocelyn R

    2017-05-01

    Recovery, profiling, and speculative searching of trace DNA (not attributable to a body fluid/cell type) over a twelve-month period in a U.S. Crime Laboratory and U.K. police force are compared. Results show greater numbers of U.S. firearm-related items submitted for analysis compared with the U.K., where greatest numbers were submitted from burglary or vehicle offenses. U.S. multiple recovery techniques (double swabbing) occurred mainly during laboratory examination, whereas the majority of U.K. multiple recovery techniques occurred at the scene. No statistical difference was observed for useful profiles from single or multiple recovery. Database loading of interpretable profiles was most successful for U.K. items related to burglary or vehicle offenses. Database associations (matches) represented 7.0% of all U.S. items and 13.1% of all U.K. items. The U.K. strategy for burglary and vehicle examination demonstrated that careful selection of both items and sampling techniques is crucial to obtaining the observed results. © 2016 American Academy of Forensic Sciences.

  17. Trace DNA Sampling Success from Evidence Items Commonly Encountered in Forensic Casework.

    PubMed

    Dziak, Renata; Peneder, Amy; Buetter, Alicia; Hageman, Cecilia

    2018-05-01

    Trace DNA analysis is a significant part of a forensic laboratory's workload. Knowing optimal sampling strategies and item success rates for particular item types can assist in evidence selection and examination processes and shorten turnaround times. In this study, forensic short tandem repeat (STR) casework results were reviewed to determine how often STR profiles suitable for comparison were obtained from "handler" and "wearer" areas of 764 items commonly submitted for examination. One hundred and fifty-five (155) items obtained from volunteers were also sampled. Items were analyzed for best sampling location and strategy. For casework items, headwear and gloves provided the highest success rates. Experimentally, eyeglasses and earphones, T-shirts, fabric gloves and watches provided the highest success rates. Eyeglasses and latex gloves provided optimal results if the entire surfaces were swabbed. In general, at least 10%, and up to 88% of all trace DNA analyses resulted in suitable STR profiles for comparison. © 2017 American Academy of Forensic Sciences.

  18. Forensic botany: usability of bryophyte material in forensic studies.

    PubMed

    Virtanen, Viivi; Korpelainen, Helena; Kostamo, Kirsi

    2007-10-25

    Two experiments were performed to test the relevance of bryophyte (Plantae, Bryophyta) material for forensic studies. The first experiment was conducted to reveal if, and how well, plant fragments attach to footwear in general. In the test, 16 persons walked outdoors wearing rubber boots or hiking boots. After 24h of use outdoors the boots were carefully cleaned, and all plant fragments were collected. Afterwards, all plant material was examined to identify the species. In the second experiment, fresh material of nine bryophyte species was kept in a shed in adverse conditions for 18 months, after which DNA was extracted and subjected to genotyping to test the quality of the material. Both experiments give support for the usability of bryophyte material in forensic studies. The bryophyte fragments become attached to shoes, where they remain even after the wearer walks on a dry road for several hours. Bryophyte DNA stays intact, allowing DNA profiling after lengthy periods following detachment from the original plant source. Based on these experiments, and considering the fact that many bryophytes are clonal plants, we propose that bryophytes are among the most usable plants to provide botanical evidence for forensic investigations.

  19. The Extraction and Recovery Efficiency of Pure DNA for Different Types of Swabs.

    PubMed

    Bruijns, Brigitte B; Tiggelaar, Roald M; Gardeniers, Han

    2018-06-11

    The extraction and recovery efficiency of swabs used to collect evidence at crime scenes is relatively low (typically <50%) for bacterial spores and body fluids. Cell-free deoxyribonucleic acid (DNA) is an interesting alternative compared to whole cells as a source for forensic analysis, but extraction and recovery from swabs has not been tested before using pure DNA. In this study cotton, foam, nylon flocked, polyester and rayon swabs are investigated in order to collect pure DNA isolated from saliva samples. The morphology and absorption capacity of swabs is studied. Extraction and recovery efficiencies are determined and compared to the maximum theoretical efficiency. The results indicate that a substantial part of DNA is not extracted from the swab and some types of swab seem to bind effectively with DNA. The efficiency of the different types of swab never exceeds 50%. The nylon flocked 4N6FLOQSwab used for buccal sampling performs the best. © 2018 The Authors. Journal of Forensic Sciences published by Wiley Periodicals, Inc. on behalf of American Academy of Forensic Sciences.

  20. The Optimization of Electrophoresis on a Glass Microfluidic Chip and its Application in Forensic Science.

    PubMed

    Han, Jun P; Sun, Jing; Wang, Le; Liu, Peng; Zhuang, Bin; Zhao, Lei; Liu, Yao; Li, Cai X

    2017-11-01

    Microfluidic chips offer significant speed, cost, and sensitivity advantages, but numerous parameters must be optimized to provide microchip electrophoresis detection. Experiments were conducted to study the factors, including sieving matrices (the concentration and type), surface modification, analysis temperature, and electric field strengths, which all impact the effectiveness of microchip electrophoresis detection of DNA samples. Our results showed that the best resolution for ssDNA was observed using 4.5% w/v (7 M urea) lab-fabricated LPA gel, dynamic wall coating of the microchannel, electrophoresis temperatures between 55 and 60°C, and electrical fields between 350 and 450 V/cm on the microchip-based capillary electrophoresis (μCE) system. One base-pair resolution could be achieved in the 19-cm-length microchannel. Furthermore, both 9947A standard genomic DNA and DNA extracted from blood spots were demonstrated to be successfully separated with well-resolved DNA peaks in 8 min. Therefore, the microchip electrophoresis system demonstrated good potential for rapid forensic DNA analysis. © 2017 American Academy of Forensic Sciences.

  1. [Analysis of genetic diversity of Russian regional populations based on common STR markers used in DNA identification].

    PubMed

    Pesik, V Yu; Fedunin, A A; Agdzhoyan, A T; Utevska, O M; Chukhraeva, M I; Evseeva, I V; Churnosov, M I; Lependina, I N; Bogunov, Yu V; Bogunova, A A; Ignashkin, M A; Yankovsky, N K; Balanovska, E V; Orekhov, V A; Balanovsky, O P

    2014-06-01

    We conducted the first genetic analysis of a wide a range of rural Russian populations in European Russia with a panel of common DNA markers commonly used in criminalistics genetic identification. We examined a total of 647 samples from indigenous ethnic Russian populations in Arkhangelsk, Belgorod, Voronezh, Kursk, Rostov, Ryazan, and Orel regions. We employed a multiplex genotyping kit, COrDIS Plus, to genotype Short Tandem Repeat (STR) loci, which included the genetic marker panel officially recommended for DNA identification in the Russian Federation, the United States, and the European Union. In the course of our study, we created a database of allelic frequencies, examined the distribution of alleles and genotypes in seven rural Russian populations, and defined the genetic relationships between these populations. We found that, although multidimensional analysis indicated a difference between the Northern gene pool and the rest of the Russian European populations, a pairwise comparison using 19 STR markers among all populations did not reveal significant differences. This is in concordance with previous studies, which examined up to 12 STR markers of urban Russian populations. Therefore, the database of allelic frequencies created in this study can be applied for forensic examinations and DNA identification among the ethnic Russian population over European Russia. We also noted a decrease in the levels of heterozygosity in the northern Russian population compared to ethnic populations in southern and central Russia, which is consistent with trends identified previously using classical gene markers and analysis of mitochondrial DNA.

  2. [The future of forensic DNA analysis for criminal justice].

    PubMed

    Laurent, François-Xavier; Vibrac, Geoffrey; Rubio, Aurélien; Thévenot, Marie-Thérèse; Pène, Laurent

    2017-11-01

    In the criminal framework, the analysis of approximately 20 DNA microsatellites enables the establishment of a genetic profile with a high statistical power of discrimination. This technique gives us the possibility to establish or exclude a match between a biological trace detected at a crime scene and a suspect whose DNA was collected via an oral swab. However, conventional techniques do tend to complexify the interpretation of complex DNA samples, such as degraded DNA and mixture DNA. The aim of this review is to highlight the powerness of new forensic DNA methods (including high-throughput sequencing or single-cell sequencing) to facilitate the interpretation of the expert with full compliance with existing french legislation. © 2017 médecine/sciences – Inserm.

  3. Identification of the skeletal remains of a murder victim by DNA analysis.

    PubMed

    Hagelberg, E; Gray, I C; Jeffreys, A J

    1991-08-01

    There is considerable anthropological and forensic interest in the possibility of DNA typing skeletal remains. Trace amounts of DNA can be recovered even from 5,500-year-old bones and multicopy human mitochondrial DNA sequences can frequently be amplified from such DNA using the polymerase chain reaction (PCR). But given the sensitivity of PCR, it is very difficult to exclude contaminating material. We now report the successful identification of the 8-year-old skeletal remains of a murder victim, by comparative typing of nuclear microsatellite markers in the remains and in the presumptive parents of the victim. This analysis establishes the authenticity of the bone DNA and the feasibility of bone DNA typing in forensic investigations.

  4. Curriculum and Course Materials for a Forensic DNA Biology Course

    ERIC Educational Resources Information Center

    Elkins, Kelly M.

    2014-01-01

    The Forensic Science Education Programs Accreditation Commission (FEPAC) requires accredited programs offer a "coherent curriculum" to ensure each student gains a "thorough grounding of the natural…sciences." Part of this curriculum includes completion of a minimum of 15 semester-hours forensic science coursework, nine of which…

  5. Comparative evaluation of different extraction and quantification methods for forensic RNA analysis.

    PubMed

    Grabmüller, Melanie; Madea, Burkhard; Courts, Cornelius

    2015-05-01

    Since about 2005, there is increasing interest in forensic RNA analysis whose versatility may very favorably complement traditional DNA profiling in forensic casework. There is, however, no method available specifically dedicated for extraction of RNA from forensically relevant sample material. In this study we compared five commercially available and commonly used RNA extraction kits and methods (mirVana™ miRNA Isolation Kit Ambion; Trizol® Reagent, Invitrogen; NucleoSpin® miRNA Kit Macherey-Nagel; AllPrep DNA/RNA Mini Kit and RNeasy® Mini Kit both Qiagen) to assess their relative effectiveness of yielding RNA of good quality and their compatibility with co-extraction of DNA amenable to STR profiling. We set up samples of small amounts of dried blood, liquid saliva, semen and buccal mucosa that were aged for different time intervals for co-extraction of RNA and DNA. RNA quality was assessed by determination of 'RNA integrity number' (RIN) and quantitative PCR based expression analysis. DNA quality was assessed via monitoring STR typing success rates. By comparison, the different methods exhibited considerable differences between RNA and DNA yields, RNA quality values and expression levels, and STR profiling success, with the AllPrep DNA/RNA Mini Kit and the NucleoSpin® miRNA Kit excelling at DNA co-extraction and RNA results, respectively. Overall, there was no 'best' method to satisfy all demands of comprehensible co-analysis of RNA and DNA and it appears that each method has specific merits and flaws. We recommend to cautiously choose from available methods and align its characteristics with the needs of the experimental setting at hand. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. The need for high-quality whole-genome sequence databases in microbial forensics.

    PubMed

    Sjödin, Andreas; Broman, Tina; Melefors, Öjar; Andersson, Gunnar; Rasmusson, Birgitta; Knutsson, Rickard; Forsman, Mats

    2013-09-01

    Microbial forensics is an important part of a strengthened capability to respond to biocrime and bioterrorism incidents to aid in the complex task of distinguishing between natural outbreaks and deliberate acts. The goal of a microbial forensic investigation is to identify and criminally prosecute those responsible for a biological attack, and it involves a detailed analysis of the weapon--that is, the pathogen. The recent development of next-generation sequencing (NGS) technologies has greatly increased the resolution that can be achieved in microbial forensic analyses. It is now possible to identify, quickly and in an unbiased manner, previously undetectable genome differences between closely related isolates. This development is particularly relevant for the most deadly bacterial diseases that are caused by bacterial lineages with extremely low levels of genetic diversity. Whole-genome analysis of pathogens is envisaged to be increasingly essential for this purpose. In a microbial forensic context, whole-genome sequence analysis is the ultimate method for strain comparisons as it is informative during identification, characterization, and attribution--all 3 major stages of the investigation--and at all levels of microbial strain identity resolution (ie, it resolves the full spectrum from family to isolate). Given these capabilities, one bottleneck in microbial forensics investigations is the availability of high-quality reference databases of bacterial whole-genome sequences. To be of high quality, databases need to be curated and accurate in terms of sequences, metadata, and genetic diversity coverage. The development of whole-genome sequence databases will be instrumental in successfully tracing pathogens in the future.

  7. Inference of biogeographical ancestry across central regions of Eurasia.

    PubMed

    Bulbul, O; Filoglu, G; Zorlu, T; Altuncul, H; Freire-Aradas, A; Söchtig, J; Ruiz, Y; Klintschar, M; Triki-Fendri, S; Rebai, A; Phillips, C; Lareu, M V; Carracedo, Á; Schneider, P M

    2016-01-01

    The inference of biogeographical ancestry (BGA) can provide useful information for forensic investigators when there are no suspects to be compared with DNA collected at the crime scene or when no DNA database matches exist. Although public databases are increasing in size and population scope, there is a lack of information regarding genetic variation in Eurasian populations, especially in central regions such as the Middle East. Inhabitants of these regions show a high degree of genetic admixture, characterized by an allele frequency cline running from NW Europe to East Asia. Although a proper differentiation has been established between the cline extremes of western Europe and South Asia, populations geographically located in between, i.e, Middle East and Mediterranean populations, require more detailed study in order to characterize their genetic background as well as to further understand their demographic histories. To initiate these studies, three ancestry informative SNP (AI-SNP) multiplex panels: the SNPforID 34-plex, Eurasiaplex and a novel 33-plex assay were used to describe the ancestry patterns of a total of 24 populations ranging across the longitudinal axis from NW Europe to East Asia. Different ancestry inference approaches, including STRUCTURE, PCA, DAPC and Snipper Bayes analysis, were applied to determine relationships among populations. The structure results show differentiation between continental groups and a NW to SE allele frequency cline running across Eurasian populations. This study adds useful population data that could be used as reference genotypes for future ancestry investigations in forensic cases. The 33-plex assay also includes pigmentation predictive SNPs, but this study primarily focused on Eurasian population differentiation using 33-plex and its combination with the other two AI-SNP sets.

  8. Identification of Forensic Samples via Mitochondrial DNA in the Undergraduate Biochemistry Laboratory

    NASA Astrophysics Data System (ADS)

    Millard, Julie T.; Pilon, André M.

    2003-04-01

    A recent forensic approach for identification of unknown biological samples is mitochondrial DNA (mtDNA) sequencing. We describe a laboratory exercise suitable for an undergraduate biochemistry course in which the polymerase chain reaction is used to amplify a 440 base pair hypervariable region of human mtDNA from a variety of "crime scene" samples (e.g., teeth, hair, nails, cigarettes, envelope flaps, toothbrushes, and chewing gum). Amplification is verified via agarose gel electrophoresis and then samples are subjected to cycle sequencing. Sequence alignments are made via the program CLUSTAL W, allowing students to compare samples and solve the "crime."

  9. Metagenomic analyses of bacteria on human hairs: a qualitative assessment for applications in forensic science.

    PubMed

    Tridico, Silvana R; Murray, Dáithí C; Addison, Jayne; Kirkbride, Kenneth P; Bunce, Michael

    2014-01-01

    Mammalian hairs are one of the most ubiquitous types of trace evidence collected in the course of forensic investigations. However, hairs that are naturally shed or that lack roots are problematic substrates for DNA profiling; these hair types often contain insufficient nuclear DNA to yield short tandem repeat (STR) profiles. Whilst there have been a number of initial investigations evaluating the value of metagenomics analyses for forensic applications (e.g. examination of computer keyboards), there have been no metagenomic evaluations of human hairs-a substrate commonly encountered during forensic practice. This present study attempts to address this forensic capability gap, by conducting a qualitative assessment into the applicability of metagenomic analyses of human scalp and pubic hair. Forty-two DNA extracts obtained from human scalp and pubic hairs generated a total of 79,766 reads, yielding 39,814 reads post control and abundance filtering. The results revealed the presence of unique combinations of microbial taxa that can enable discrimination between individuals and signature taxa indigenous to female pubic hairs. Microbial data from a single co-habiting couple added an extra dimension to the study by suggesting that metagenomic analyses might be of evidentiary value in sexual assault cases when other associative evidence is not present. Of all the data generated in this study, the next-generation sequencing (NGS) data generated from pubic hair held the most potential for forensic applications. Metagenomic analyses of human hairs may provide independent data to augment other forensic results and possibly provide association between victims of sexual assault and offender when other associative evidence is absent. Based on results garnered in the present study, we believe that with further development, bacterial profiling of hair will become a valuable addition to the forensic toolkit.

  10. On compensation of mismatched recording conditions in the Bayesian approach for forensic automatic speaker recognition.

    PubMed

    Botti, F; Alexander, A; Drygajlo, A

    2004-12-02

    This paper deals with a procedure to compensate for mismatched recording conditions in forensic speaker recognition, using a statistical score normalization. Bayesian interpretation of the evidence in forensic automatic speaker recognition depends on three sets of recordings in order to perform forensic casework: reference (R) and control (C) recordings of the suspect, and a potential population database (P), as well as a questioned recording (QR) . The requirement of similar recording conditions between suspect control database (C) and the questioned recording (QR) is often not satisfied in real forensic cases. The aim of this paper is to investigate a procedure of normalization of scores, which is based on an adaptation of the Test-normalization (T-norm) [2] technique used in the speaker verification domain, to compensate for the mismatch. Polyphone IPSC-02 database and ASPIC (an automatic speaker recognition system developed by EPFL and IPS-UNIL in Lausanne, Switzerland) were used in order to test the normalization procedure. Experimental results for three different recording condition scenarios are presented using Tippett plots and the effect of the compensation on the evaluation of the strength of the evidence is discussed.

  11. A sensitive method to extract DNA from biological traces present on ammunition for the purpose of genetic profiling.

    PubMed

    Dieltjes, Patrick; Mieremet, René; Zuniga, Sofia; Kraaijenbrink, Thirsa; Pijpe, Jeroen; de Knijff, Peter

    2011-07-01

    Exploring technological limits is a common practice in forensic DNA research. Reliable genetic profiling based on only a few cells isolated from trace material retrieved from a crime scene is nowadays more and more the rule rather than the exception. On many crime scenes, cartridges, bullets, and casings (jointly abbreviated as CBCs) are regularly found, and even after firing, these potentially carry trace amounts of biological material. Since 2003, the Forensic Laboratory for DNA Research is routinely involved in the forensic investigation of CBCs in the Netherlands. Reliable DNA profiles were frequently obtained from CBCs and used to match suspects, victims, or other crime scene-related DNA traces. In this paper, we describe the sensitive method developed by us to extract DNA from CBCs. Using PCR-based genotyping of autosomal short tandem repeats, we were able to obtain reliable and reproducible DNA profiles in 163 out of 616 criminal cases (26.5%) and in 283 out of 4,085 individual CBC items (6.9%) during the period January 2003-December 2009. We discuss practical aspects of the method and the sometimes unexpected effects of using cell lysis buffer on the subsequent investigation of striation patterns on CBCs.

  12. "New turns from old STaRs": enhancing the capabilities of forensic short tandem repeat analysis.

    PubMed

    Phillips, Christopher; Gelabert-Besada, Miguel; Fernandez-Formoso, Luis; García-Magariños, Manuel; Santos, Carla; Fondevila, Manuel; Ballard, David; Syndercombe Court, Denise; Carracedo, Angel; Lareu, Maria Victoria

    2014-11-01

    The field of research and development of forensic STR genotyping remains active, innovative, and focused on continuous improvements. A series of recent developments including the introduction of a sixth dye have brought expanded STR multiplex sizes while maintaining sensitivity to typical forensic DNA. New supplementary kits complimenting the core STRs have also helped improve analysis of challenging identification cases such as distant pairwise relationships in deficient pedigrees. This article gives an overview of several recent key developments in forensic STR analysis: availability of expanded core STR kits and supplementary STRs, short-amplicon mini-STRs offering practical options for highly degraded DNA, Y-STR enhancements made from the identification of rapidly mutating loci, and enhanced analysis of genetic ancestry by analyzing 32-STR profiles with a Bayesian forensic classifier originally developed for SNP population data. As well as providing scope for genotyping larger numbers of STRs optimized for forensic applications, the launch of compact next-generation sequencing systems provides considerable potential for genotyping the sizeable proportion of nucleotide variation existing in forensic STRs, which currently escapes detection with CE. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Forensic genetic informativeness of an SNP panel consisting of 19 multi-allelic SNPs.

    PubMed

    Gao, Zehua; Chen, Xiaogang; Zhao, Yuancun; Zhao, Xiaohong; Zhang, Shu; Yang, Yiwen; Wang, Yufang; Zhang, Ji

    2018-05-01

    Current research focusing on forensic personal identification, phenotype inference and ancestry information on single-nucleotide polymorphisms (SNPs) has been widely reported. In the present study, we focused on tetra-allelic SNPs in the Chinese Han population. A total of 48 tetra-allelic SNPs were screened out from the Chinese Han population of the 1000 Genomes Database, including Chinese Han in Beijing (CHB) and Chinese Han South (CHS). Considering the forensic genetic requirement for the polymorphisms, only 11 tetra-allelic SNPs with a heterozygosity >0.06 were selected for further multiplex panel construction. In order to meet the demands of personal identification and parentage identification, an additional 8 tri-allelic SNPs were combined into the final multiplex panel. To ensure application in the degraded DNA analysis, all the PCR products were designed to be 87-188 bp. Employing multiple PCR reactions and SNaPshot minisequencing, 511 unrelated Chinese Han individuals from Sichuan were genotyped. The combined match probability (CMP), combined discrimination power (CDP), and cumulative probability of exclusion (CPE) of the panel were 6.07 × 10 -11 , 0.9999999999393 and 0.996764, respectively. Based on the population data retrieved from the 1000 Genomes Project, Fst values between Chinese Han in Sichuan (SCH) and all the populations included in the 1000 Genomes Project were calculated. The results indicated that two SNPs in this panel may contain ancestry information and may be used as markers of forensic biogeographical ancestry inference. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. The impact of modern migrations on present-day multi-ethnic Argentina as recorded on the mitochondrial DNA genome.

    PubMed

    Catelli, María Laura; Alvarez-Iglesias, Vanesa; Gómez-Carballa, Alberto; Mosquera-Miguel, Ana; Romanini, Carola; Borosky, Alicia; Amigo, Jorge; Carracedo, Angel; Vullo, Carlos; Salas, Antonio

    2011-08-30

    The genetic background of Argentineans is a mosaic of different continental ancestries. From colonial to present times, the genetic contribution of Europeans and sub-Saharan Africans has superposed to or replaced the indigenous genetic 'stratum'. A sample of 384 individuals representing different Argentinean provinces was collected and genotyped for the first and the second mitochondrial DNA (mtDNA) hypervariable regions, and selectively genotyped for mtDNA SNPs. This data was analyzed together with additional 440 profiles from rural and urban populations plus 304 from Native American Argentineans, all available from the literature. A worldwide database was used for phylogeographic inferences, inter-population comparisons, and admixture analysis. Samples identified as belonging to hg (hg) H2a5 were sequenced for the entire mtDNA genome. Phylogenetic and admixture analyses indicate that only half of the Native American component in urban Argentineans might be attributed to the legacy of extinct ancestral Argentineans and that the Spanish genetic contribution is slightly higher than the Italian one. Entire H2a5 genomes linked these Argentinean mtDNAs to the Basque Country and improved the phylogeny of this Basque autochthonous clade. The fingerprint of African slaves in urban Argentinean mtDNAs was low and it can be phylogeographically attributed predominantly to western African. The European component is significantly more prevalent in the Buenos Aires province, the main gate of entrance for Atlantic immigration to Argentina, while the Native American component is larger in North and South Argentina. AMOVA, Principal Component Analysis and hgs/haplotype patterns in Argentina revealed an important level of genetic sub-structure in the country. Studies aimed to compare mtDNA frequency profiles from different Argentinean geographical regions (e.g., forensic and case-control studies) should take into account the important genetic heterogeneity of the country in order to prevent false positive claims of association in disease studies or inadequate evaluation of forensic evidence.

  15. The impact of modern migrations on present-day multi-ethnic Argentina as recorded on the mitochondrial DNA genome

    PubMed Central

    2011-01-01

    Background The genetic background of Argentineans is a mosaic of different continental ancestries. From colonial to present times, the genetic contribution of Europeans and sub-Saharan Africans has superposed to or replaced the indigenous genetic 'stratum'. A sample of 384 individuals representing different Argentinean provinces was collected and genotyped for the first and the second mitochondrial DNA (mtDNA) hypervariable regions, and selectively genotyped for mtDNA SNPs. This data was analyzed together with additional 440 profiles from rural and urban populations plus 304 from Native American Argentineans, all available from the literature. A worldwide database was used for phylogeographic inferences, inter-population comparisons, and admixture analysis. Samples identified as belonging to hg (hg) H2a5 were sequenced for the entire mtDNA genome. Results Phylogenetic and admixture analyses indicate that only half of the Native American component in urban Argentineans might be attributed to the legacy of extinct ancestral Argentineans and that the Spanish genetic contribution is slightly higher than the Italian one. Entire H2a5 genomes linked these Argentinean mtDNAs to the Basque Country and improved the phylogeny of this Basque autochthonous clade. The fingerprint of African slaves in urban Argentinean mtDNAs was low and it can be phylogeographically attributed predominantly to western African. The European component is significantly more prevalent in the Buenos Aires province, the main gate of entrance for Atlantic immigration to Argentina, while the Native American component is larger in North and South Argentina. AMOVA, Principal Component Analysis and hgs/haplotype patterns in Argentina revealed an important level of genetic sub-structure in the country. Conclusions Studies aimed to compare mtDNA frequency profiles from different Argentinean geographical regions (e.g., forensic and case-control studies) should take into account the important genetic heterogeneity of the country in order to prevent false positive claims of association in disease studies or inadequate evaluation of forensic evidence. PMID:21878127

  16. Accuracy Rates of Sex Estimation by Forensic Anthropologists through Comparison with DNA Typing Results in Forensic Casework.

    PubMed

    Thomas, Richard M; Parks, Connie L; Richard, Adam H

    2016-09-01

    A common task in forensic anthropology involves the estimation of the biological sex of a decedent by exploiting the sexual dimorphism between males and females. Estimation methods are often based on analysis of skeletal collections of known sex and most include a research-based accuracy rate. However, the accuracy rates of sex estimation methods in actual forensic casework have rarely been studied. This article uses sex determinations based on DNA results from 360 forensic cases to develop accuracy rates for sex estimations conducted by forensic anthropologists. The overall rate of correct sex estimation from these cases is 94.7% with increasing accuracy rates as more skeletal material is available for analysis and as the education level and certification of the examiner increases. Nine of 19 incorrect assessments resulted from cases in which one skeletal element was available, suggesting that the use of an "undetermined" result may be more appropriate for these cases. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

  17. [Applications of DNA methylation markers in forensic medicine].

    PubMed

    Zhao, Gui-sen; Yang, Qing-en

    2005-02-01

    DNA methylation is a post-replication modification that is predominantly found in cytosines of the dinucleotide sequence CpG. Epigenetic information is stored in the distribution of the modified base 5-methylcytosine. DNA methylation profiles represent a more chemically and biologically stable source of molecular diagnostic information than RNA or most proteins. Recent advances attest to the great promise of DNA methylation markers as powerful future tools in the clinic. In the past decade, DNA methylation analysis has been revolutionized by two technological advances--bisulphite modification of DNA and methylation-specific polymerase chain reaction (MSP). The methylation pattern of human genome is space-time specific, sex-specific, parent-of-origin specific and disease specific, providing us an alternative way to solve forensic problems.

  18. Multiplex pyrosequencing of InDel markers for forensic DNA analysis.

    PubMed

    Bus, Magdalena M; Karas, Ognjen; Allen, Marie

    2016-12-01

    The capillary electrophoresis (CE) technology is commonly used for fragment length separation of markers in forensic DNA analysis. In this study, pyrosequencing technology was used as an alternative and rapid tool for the analysis of biallelic InDel (insertion/deletion) markers for individual identification. The DNA typing is based on a subset of the InDel markers that are included in the Investigator ® DIPplex Kit, which are sequenced in a multiplex pyrosequencing analysis. To facilitate the analysis of degraded DNA, the polymerase chain reaction (PCR) fragments were kept short in the primer design. Samples from individuals of Swedish origin were genotyped using the pyrosequencing strategy and analysis of the Investigator ® DIPplex markers with CE. A comparison between the pyrosequencing and CE data revealed concordant results demonstrating a robust and correct genotyping by pyrosequencing. Using optimal marker combination and a directed dispensation strategy, five markers could be multiplexed and analyzed simultaneously. In this proof-of-principle study, we demonstrate that multiplex InDel pyrosequencing analysis is possible. However, further studies on degraded samples, lower DNA quantities, and mixtures will be required to fully optimize InDel analysis by pyrosequencing for forensic applications. Overall, although CE analysis is implemented in most forensic laboratories, multiplex InDel pyrosequencing offers a cost-effective alternative for some applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. [DNA Extraction from Old Bones by AutoMate Express™ System].

    PubMed

    Li, B; Lü, Z

    2017-08-01

    To establish a method for extracting DNA from old bones by AutoMate Express™ system. Bones were grinded into powder by freeze-mill. After extraction by AutoMate Express™, DNA were amplified and genotyped by Identifiler®Plus and MinFiler™ kits. DNA were extracted from 10 old bone samples, which kept in different environments with the postmortem interval from 10 to 20 years, in 3 hours by AutoMate Express™ system. Complete STR typing results were obtained from 8 samples. AutoMate Express™ system can quickly and efficiently extract DNA from old bones, which can be applied in forensic practice. Copyright© by the Editorial Department of Journal of Forensic Medicine

  20. Vanadium accelerates polymerase chain reaction and expands the applicability of forensic DNA testing.

    PubMed

    Kaminiwa, Junko; Honda, Katsuya; Sugano, Yukiko; Yano, Shizue; Nishi, Takeki; Sekine, Yuko

    2013-05-01

    Polymerase chain reaction (PCR) has been rapidly established as one of the most widely used techniques in molecular biology. Because most DNA analysis is PCR-based, the analysis of unamplifiable DNA of poor quality or low quantity is nearly impossible. However, we observed that if an appropriate concentration of vanadium chloride is added to the standard reaction mixture, the enzymatic amplification of DNA could be enhanced. Using multiplex PCR with the addition of vanadium, DNA typing was possible from even trace amounts of DNA that we were unable to amplify using normal reaction conditions. This method might be an effective tool for not only criminal investigations and ancient DNA analysis, but also for nearly all fields using DNA technology. Copyright © 2012 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  1. Facial soft biometric features for forensic face recognition.

    PubMed

    Tome, Pedro; Vera-Rodriguez, Ruben; Fierrez, Julian; Ortega-Garcia, Javier

    2015-12-01

    This paper proposes a functional feature-based approach useful for real forensic caseworks, based on the shape, orientation and size of facial traits, which can be considered as a soft biometric approach. The motivation of this work is to provide a set of facial features, which can be understood by non-experts such as judges and support the work of forensic examiners who, in practice, carry out a thorough manual comparison of face images paying special attention to the similarities and differences in shape and size of various facial traits. This new approach constitutes a tool that automatically converts a set of facial landmarks to a set of features (shape and size) corresponding to facial regions of forensic value. These features are furthermore evaluated in a population to generate statistics to support forensic examiners. The proposed features can also be used as additional information that can improve the performance of traditional face recognition systems. These features follow the forensic methodology and are obtained in a continuous and discrete manner from raw images. A statistical analysis is also carried out to study the stability, discrimination power and correlation of the proposed facial features on two realistic databases: MORPH and ATVS Forensic DB. Finally, the performance of both continuous and discrete features is analyzed using different similarity measures. Experimental results show high discrimination power and good recognition performance, especially for continuous features. A final fusion of the best systems configurations achieves rank 10 match results of 100% for ATVS database and 75% for MORPH database demonstrating the benefits of using this information in practice. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Introducing the Forensic Research/Reference on Genetics knowledge base, FROG-kb.

    PubMed

    Rajeevan, Haseena; Soundararajan, Usha; Pakstis, Andrew J; Kidd, Kenneth K

    2012-09-01

    Online tools and databases based on multi-allelic short tandem repeat polymorphisms (STRPs) are actively used in forensic teaching, research, and investigations. The Fst value of each CODIS marker tends to be low across the populations of the world and most populations typically have all the common STRP alleles present diminishing the ability of these systems to discriminate ethnicity. Recently, considerable research is being conducted on single nucleotide polymorphisms (SNPs) to be considered for human identification and description. However, online tools and databases that can be used for forensic research and investigation are limited. The back end DBMS (Database Management System) for FROG-kb is Oracle version 10. The front end is implemented with specific code using technologies such as Java, Java Servlet, JSP, JQuery, and GoogleCharts. We present an open access web application, FROG-kb (Forensic Research/Reference on Genetics-knowledge base, http://frog.med.yale.edu), that is useful for teaching and research relevant to forensics and can serve as a tool facilitating forensic practice. The underlying data for FROG-kb are provided by the already extensively used and referenced ALlele FREquency Database, ALFRED (http://alfred.med.yale.edu). In addition to displaying data in an organized manner, computational tools that use the underlying allele frequencies with user-provided data are implemented in FROG-kb. These tools are organized by the different published SNP/marker panels available. This web tool currently has implemented general functions possible for two types of SNP panels, individual identification and ancestry inference, and a prediction function specific to a phenotype informative panel for eye color. The current online version of FROG-kb already provides new and useful functionality. We expect FROG-kb to grow and expand in capabilities and welcome input from the forensic community in identifying datasets and functionalities that will be most helpful and useful. Thus, the structure and functionality of FROG-kb will be revised in an ongoing process of improvement. This paper describes the state as of early June 2012.

  3. [Practice value of whole genome amplification technology to be used in forensic science and analysis of its result].

    PubMed

    Deng, Jian-qiang; Hou, Yi-ping

    2005-08-01

    Genetic analysis from forensic microsamples is a urgent, difficult task in forensic science, because it is frequently limited by the amount of specimen available in forensic practice, much effort has been carried out to resolve this difficulty. Whole genome amplification (WGA) technology, which was developing quickly in these years, has been thought to be a powerful, reliable and efficient strategy in analysis of minute amount DNA on many fields. In this review, we discuss its application in forensic science.

  4. Using the Developmental Gene Bicoid to Identify Species of Forensically Important Blowflies (Diptera: Calliphoridae)

    PubMed Central

    Park, Seong Hwan; Park, Chung Hyun; Zhang, Yong; Piao, Huguo; Chung, Ukhee; Kim, Seong Yoon; Ko, Kwang Soo; Yi, Cheong-Ho; Jo, Tae-Ho; Hwang, Juck-Joon

    2013-01-01

    Identifying species of insects used to estimate postmortem interval (PMI) is a major subject in forensic entomology. Because forensic insect specimens are morphologically uniform and are obtained at various developmental stages, DNA markers are greatly needed. To develop new autosomal DNA markers to identify species, partial genomic sequences of the bicoid (bcd) genes, containing the homeobox and its flanking sequences, from 12 blowfly species (Aldrichina grahami, Calliphora vicina, Calliphora lata, Triceratopyga calliphoroides, Chrysomya megacephala, Chrysomya pinguis, Phormia regina, Lucilia ampullacea, Lucilia caesar, Lucilia illustris, Hemipyrellia ligurriens and Lucilia sericata; Calliphoridae: Diptera) were determined and analyzed. This study first sequenced the ten blowfly species other than C. vicina and L. sericata. Based on the bcd sequences of these 12 blowfly species, a phylogenetic tree was constructed that discriminates the subfamilies of Calliphoridae (Luciliinae, Chrysomyinae, and Calliphorinae) and most blowfly species. Even partial genomic sequences of about 500 bp can distinguish most blowfly species. The short intron 2 and coding sequences downstream of the bcd homeobox in exon 3 could be utilized to develop DNA markers for forensic applications. These gene sequences are important in the evolution of insect developmental biology and are potentially useful for identifying insect species in forensic science. PMID:23586044

  5. The impact of chimerism in DNA-based forensic sex determination analysis.

    PubMed

    George, Renjith; Donald, Preethy Mary; Nagraj, Sumanth Kumbargere; Idiculla, Jose Joy; Hj Ismail, Rashid

    2013-01-01

    Sex determination is the most important step in personal identification in forensic investigations. DNA-based sex determination analysis is comparatively more reliable than the other conventional methods of sex determination analysis. Advanced technology like real-time polymerase chain reaction (PCR) offers accurate and reproducible results and is at the level of legal acceptance. But still there are situations like chimerism where an individual possess both male and female specific factors together in their body. Sex determination analysis in such cases can give erroneous results. This paper discusses the phenomenon of chimerism and its impact on sex determination analysis in forensic investigations.

  6. Science, truth, and forensic cultures: the exceptional legal status of DNA evidence.

    PubMed

    Lynch, Michael

    2013-03-01

    Many epistemological terms, such as investigation, inquiry, argument, evidence, and fact were established in law well before being associated with science. However, while legal proof remained qualified by standards of 'moral certainty', scientific proof attained a reputation for objectivity. Although most forms of legal evidence (including expert evidence) continue to be treated as fallible 'opinions' rather than objective 'facts', forensic DNA evidence increasingly is being granted an exceptional factual status. It did not always enjoy such status. Two decades ago, the scientific status of forensic DNA evidence was challenged in the scientific literature and in courts of law, but by the late 1990s it was being granted exceptional legal status. This paper reviews the ascendancy of DNA profiling, and argues that its widely-heralded objective status is bound up with systems of administrative accountability. The 'administrative objectivity' of DNA evidence rests upon observable and reportable bureaucratic rules, records, recording devices, protocols, and architectural arrangements. By highlighting administrative sources of objectivity, this paper suggests that DNA evidence remains bound within the context of ordinary organisational and practical routines, and is not a transcendent source of 'truth' in the criminal justice system. Copyright © 2012. Published by Elsevier Ltd.

  7. Forensic genetic analysis of bio-geographical ancestry.

    PubMed

    Phillips, Chris

    2015-09-01

    With the great strides made in the last ten years in the understanding of human population variation and the detailed characterization of the genome, it is now possible to identify sets of ancestry informative markers suitable for relatively small-scale PCR-based assays and use them to analyze the ancestry of an individual from forensic DNA. This review outlines some of the current understanding of past human population structure and how it may have influenced the complex distribution of contemporary human diversity. A simplified description of human diversity can provide a suitable basis for choosing the best ancestry-informative markers, which is important given the constraints of multiplex sizes in forensic DNA tests. It is also important to decide the level of geographic resolution that is realistic to ensure the balance between informativeness and an over-simplification of complex human diversity patterns. A detailed comparison is made of the most informative ancestry markers suitable for forensic use and assessments are made of the data analysis regimes that can provide statistical inferences of a DNA donor's bio-geographical ancestry. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  8. An Optimized Centrifugal Method for Separation of Semen from Superabsorbent Polymers for Forensic Analysis.

    PubMed

    Camarena, Lucy R; Glasscock, Bailey K; Daniels, Demi; Ackley, Nicolle; Sciarretta, Marybeth; Seashols-Williams, Sarah J

    2017-03-01

    Connection of a perpetrator to a sexual assault is best performed through the confirmed presence of semen, thereby proving sexual contact. Evidentiary items can include sanitary napkins or diapers containing superabsorbent polymers (SAPs), complicating spermatozoa visualization and DNA analysis. In this report, we evaluated the impact of SAPS on the current forensic DNA workflow, developing an efficient centrifugal protocol for separating spermatozoa from SAP material. The optimized filtration method was compared to common practices of excising the top layer only, resulting in significantly higher sperm yields when a core sample of the substrate was taken. Direct isolation of the SAP-containing materials without filtering resulted in 20% sample failure; additionally, SAP material was observed in the final eluted DNA samples, causing physical interference. Thus, use of the described centrifugal-filtering method is a simple preliminary step that improves spermatozoa visualization and enables more consistent DNA yields, while also avoiding SAP interference. © 2016 American Academy of Forensic Sciences.

  9. Forensic identification of Indian snakeroot (Rauvolfia serpentina Benth. ex Kurz) using DNA barcoding.

    PubMed

    Eurlings, Marcel C M; Lens, Frederic; Pakusza, Csilla; Peelen, Tamara; Wieringa, Jan J; Gravendeel, Barbara

    2013-05-01

    Indian snakeroot (Rauvolfia serpentina) is a valuable forest product, root extracts of which are used as an antihypertensive drug. Increasing demand led to overharvesting in the wild. Control of international trade is hampered by the inability to identify root samples to the species level. We therefore evaluated the potential of molecular identification by searching for species-specific DNA polymorphisms. We found two species-specific indels in the rps16 intron region for R. serpentina. Our DNA barcoding method was tested for its specificity, reproducibility, sensitivity and stability. We included samples of various tissues and ages, which had been treated differently for preservation. DNA extractions were tested in a range of amplification settings and dilutions. Species-specific rps16 intron sequences were obtained from 79 herbarium accessions and one confiscated root, encompassing 39 different species. Our results demonstrate that molecular analysis provides new perspectives for forensic identification of Indian snakeroot. © 2013 American Academy of Forensic Sciences.

  10. Enhanced Genetic Analysis of Single Human Bioparticles Recovered by Simplified Micromanipulation from Forensic ‘Touch DNA’ Evidence

    PubMed Central

    Farash, Katherine; Hanson, Erin K.; Ballantyne, Jack

    2015-01-01

    DNA profiles can be obtained from ‘touch DNA’ evidence, which comprises microscopic traces of human biological material. Current methods for the recovery of trace DNA employ cotton swabs or adhesive tape to sample an area of interest. However, such a ‘blind-swabbing’ approach will co-sample cellular material from the different individuals, even if the individuals’ cells are located in geographically distinct locations on the item. Thus, some of the DNA mixtures encountered in touch DNA samples are artificially created by the swabbing itself. In some instances, a victim’s DNA may be found in significant excess thus masking any potential perpetrator’s DNA. In order to circumvent the challenges with standard recovery and analysis methods, we have developed a lower cost, ‘smart analysis’ method that results in enhanced genetic analysis of touch DNA evidence. We describe an optimized and efficient micromanipulation recovery strategy for the collection of bio-particles present in touch DNA samples, as well as an enhanced amplification strategy involving a one-step 5 µl microvolume lysis/STR amplification to permit the recovery of STR profiles from the bio-particle donor(s). The use of individual or few (i.e., “clumps”) bioparticles results in the ability to obtain single source profiles. These procedures represent alternative enhanced techniques for the isolation and analysis of single bioparticles from forensic touch DNA evidence. While not necessary in every forensic investigation, the method could be highly beneficial for the recovery of a single source perpetrator DNA profile in cases involving physical assault (e.g., strangulation) that may not be possible using standard analysis techniques. Additionally, the strategies developed here offer an opportunity to obtain genetic information at the single cell level from a variety of other non-forensic trace biological material. PMID:25867046

  11. Application of HLA-DRB1 genotyping by oligonucleotide micro-array technology in forensic medicine.

    PubMed

    Jiang, Bin; Li, Yao; Wu, Hai; He, Xianmin; Li, Chengtao; Li, Li; Tang, Rong; Xie, Yi; Mao, Yumin

    2006-10-16

    The human leukocyte antigen (HLA) system is known to be the most complex polymorphic system in the human genome. Among all of the HLA loci, HLA-DRB1 has the second largest number of alleles. The purpose of this study is to develop an oligonucleotide micro-array based HLA-DRB1 typing system for use in forensic identification, anthropology, tissue transplantation, and other genetic research fields. The system was developed by analyzing the HLA-DRB1 (DRB1) genotypes in 1198 unrelated healthy Chinese Han individuals originating from various parts of China and residing in Shanghai, China. Polymerase chain reaction (PCR) coupled with the oligonucleotide micro-array technology was used to detect and type HLA-DRB1 alleles of the sample individuals. The reliability, sensitivity, consistency and specificity were evaluated for use in forensic identification. Furthermore, a meta-analysis was carried out by comparing the allele frequencies of the HLA-DRB1 locus with those of other Chinese Han groups, Chinese minorities and other ethnic populations. All the DNA samples yielded a 273 bp amplification product, with no other amplification products in this length range. The minimum quantity of DNA detected by this method is 15 ng in a PCR reaction system of 25 microl. The population studied appeared to be not in Hardy-Weinberg equilibrium. Observed heterozygosity (Ho), expected heterozygosity (He), expected probability of exclusion (PE), polymorphic information content (PIC), and discrimination power (DP) of the HLA-DRB1 locus from the Shanghai Han ethnic group were evaluated to be 0.8022, 0.8870, 0.7741, 0.8771, 0.9750, respectively. A total of 25 HLA-DRB1 alleles were identified. HLA-DRB1*09XX, *04XX, *12XX and *15XX were the most frequent DRB1 alleles, which were observed in 58.76% of the sample. One hundred and sixteen genotypes were found. The five most frequent genotypes were: *04XX/*04XX (0.0626), *09XX/*09XX (0.0593), *04XX/*09XX (0.0551), *09XX/*15XX (0.0384) and *08XX/*12XX (0.0351). The meta-analysis showed that there were uniquely distributed features of DRB1 alleles among various ethnic populations and among the studied population groups from various regions with the same ethnic origin. An HLA-DRB1 genotyping system has been developed and established based on the oligonucleotide micro-array technology. The HLA-DRB1 typing of the Han population in Shanghai has revealed a relatively high heterogeneity. Information obtained in this study will be useful for medical and forensic applications as well as in anthropology research. Large-scale micro-array detection is highly accurate and reliable for DNA-based HLA-DRB1 genotyping. These results suggest that HLA-DRB1 DNA polymorphisms and the database of the Shanghai Han group have useful applications in processing forensic casework (as personal identification, paternity test), tracing population migration and genetic diagnosis.

  12. Whole genome nucleosome sequencing identifies novel types of forensic markers in degraded DNA samples

    PubMed Central

    Dong, Chun-nan; Yang, Ya-dong; Li, Shu-jin; Yang, Ya-ran; Zhang, Xiao-jing; Fang, Xiang-dong; Yan, Jiang-wei; Cong, Bin

    2016-01-01

    In the case of mass disasters, missing persons and forensic caseworks, highly degraded biological samples are often encountered. It can be a challenge to analyze and interpret the DNA profiles from these samples. Here we provide a new strategy to solve the problem by taking advantage of the intrinsic structural properties of DNA. We have assessed the in vivo positions of more than 35 million putative nucleosome cores in human leukocytes using high-throughput whole genome sequencing, and identified 2,462 single nucleotide variations (SNVs), 128 insertion-deletion polymorphisms (indels). After comparing the sequence reads with 44 STR loci commonly used in forensics, five STRs (TH01, TPOX, D18S51, DYS391, and D10S1248)were matched. We compared these “nucleosome protected STRs” (NPSTRs) with five other non-NPSTRs using mini-STR primer design, real-time PCR, and capillary gel electrophoresis on artificially degraded DNA. Moreover, genotyping performance of the five NPSTRs and five non-NPSTRs was also tested with real casework samples. All results show that loci located in nucleosomes are more likely to be successfully genotyped in degraded samples. In conclusion, after further strict validation, these markers could be incorporated into future forensic and paleontology identification kits, resulting in higher discriminatory power for certain degraded sample types. PMID:27189082

  13. Population-scale whole genome sequencing identifies 271 highly polymorphic short tandem repeats from Japanese population.

    PubMed

    Hirata, Satoshi; Kojima, Kaname; Misawa, Kazuharu; Gervais, Olivier; Kawai, Yosuke; Nagasaki, Masao

    2018-05-01

    Forensic DNA typing is widely used to identify missing persons and plays a central role in forensic profiling. DNA typing usually uses capillary electrophoresis fragment analysis of PCR amplification products to detect the length of short tandem repeat (STR) markers. Here, we analyzed whole genome data from 1,070 Japanese individuals generated using massively parallel short-read sequencing of 162 paired-end bases. We have analyzed 843,473 STR loci with two to six basepair repeat units and cataloged highly polymorphic STR loci in the Japanese population. To evaluate the performance of the cataloged STR loci, we compared 23 STR loci, widely used in forensic DNA typing, with capillary electrophoresis based STR genotyping results in the Japanese population. Seventeen loci had high correlations and high call rates. The other six loci had low call rates or low correlations due to either the limitations of short-read sequencing technology, the bioinformatics tool used, or the complexity of repeat patterns. With these analyses, we have also purified the suitable 218 STR loci with four basepair repeat units and 53 loci with five basepair repeat units both for short read sequencing and PCR based technologies, which would be candidates to the actual forensic DNA typing in Japanese population.

  14. Comparison of hard tissues that are useful for DNA analysis in forensic autopsy.

    PubMed

    Kaneko, Yu; Ohira, Hiroshi; Tsuda, Yukio; Yamada, Yoshihiro

    2015-11-01

    Forensic analysis of DNA from hard tissues can be important when investigating a variety of cases resulting from mass disaster or criminal cases. This study was conducted to evaluate the most suitable tissues, method and sample size for processing of hard tissues prior to DNA isolation. We also evaluated the elapsed time after death in relation to the quantity of DNA extracted. Samples of hard tissues (37 teeth, 42 skull, 42 rib, and 39 nails) from 42 individuals aged between 50 and 83 years were used. The samples were taken from remains following forensic autopsy (from 2 days to 2 years after death). To evaluate the integrity of the nuclear DNA isolated, the percentage of allele calls for short tandem repeat profiles were compared between the hard tissues. DNA typing results indicated that until 1 month after death, any of the four hard tissue samples could be used as an alternative to teeth, allowing analysis of all of the loci. However, in terms of the sampling site, collection method and sample size adjustment, the rib appeared to be the best choice in view of the ease of specimen preparation. Our data suggest that the rib could be an alternative hard tissue sample for DNA analysis of human remains. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. DNA testing in homicide investigations.

    PubMed

    Prahlow, Joseph A; Cameron, Thomas; Arendt, Alexander; Cornelis, Kenneth; Bontrager, Anthony; Suth, Michael S; Black, Lisa; Tobey, Rebbecca; Pollock, Sharon; Stur, Shawn; Cotter, Kenneth; Gabrielse, Joel

    2017-10-01

    Objectives With the widespread use of DNA testing, police, death investigators, and attorneys need to be aware of the capabilities of this technology. This review provides an overview of scenarios where DNA evidence has played a major role in homicide investigations in order to highlight important educational issues for police, death investigators, forensic pathologists, and attorneys. Methods This was a nonrandom, observational, retrospective study. Data were obtained from the collective files of the authors from casework during a 15-year period, from 2000 through 2014. Results A series of nine scenarios, encompassing 11 deaths, is presented from the standpoint of the police and death investigation, the forensic pathology autopsy performance, the subsequent DNA testing of evidence, and, ultimately, the final adjudication of cases. Details of each case are presented, along with a discussion that focuses on important aspects of sample collection for potential DNA testing, especially at the crime scene and the autopsy. The presentation highlights the diversity of case and evidence types in which DNA testing played a valuable role in the successful prosecution of the case. Conclusions By highlighting homicides where DNA testing contributed to the successful adjudication of cases, police, death investigators, forensic pathologists, and attorneys will be better informed regarding the types of evidence and situations where such testing is of potential value.

  16. Colombian forensic genetics as a form of public science: The role of race, nation and common sense in the stabilization of DNA populations.

    PubMed

    Schwartz-Marín, Ernesto; Wade, Peter; Cruz-Santiago, Arely; Cárdenas, Roosbelinda

    2015-12-01

    Abstract This article examines the role that vernacular notions of racialized-regional difference play in the constitution and stabilization of DNA populations in Colombian forensic science, in what we frame as a process of public science. In public science, the imaginations of the scientific world and common-sense public knowledge are integral to the production and circulation of science itself. We explore the origins and circulation of a scientific object--'La Tabla', published in Paredes et al. and used in genetic forensic identification procedures--among genetic research institutes, forensic genetics laboratories and courtrooms in Bogotá. We unveil the double life of this central object of forensic genetics. On the one hand, La Tabla enjoys an indisputable public place in the processing of forensic genetic evidence in Colombia (paternity cases, identification of bodies, etc.). On the other hand, the relations it establishes between 'race', geography and genetics are questioned among population geneticists in Colombia. Although forensic technicians are aware of the disputes among population geneticists, they use and endorse the relations established between genetics, 'race' and geography because these fit with common-sense notions of visible bodily difference and the regionalization of race in the Colombian nation.

  17. Colombian forensic genetics as a form of public science: The role of race, nation and common sense in the stabilization of DNA populations

    PubMed Central

    Schwartz-Marín, Ernesto; Wade, Peter; Cruz-Santiago, Arely; Cárdenas, Roosbelinda

    2015-01-01

    This article examines the role that vernacular notions of racialized-regional difference play in the constitution and stabilization of DNA populations in Colombian forensic science, in what we frame as a process of public science. In public science, the imaginations of the scientific world and common-sense public knowledge are integral to the production and circulation of science itself. We explore the origins and circulation of a scientific object – ‘La Tabla’, published in Paredes et al. and used in genetic forensic identification procedures – among genetic research institutes, forensic genetics laboratories and courtrooms in Bogotá. We unveil the double life of this central object of forensic genetics. On the one hand, La Tabla enjoys an indisputable public place in the processing of forensic genetic evidence in Colombia (paternity cases, identification of bodies, etc.). On the other hand, the relations it establishes between ‘race’, geography and genetics are questioned among population geneticists in Colombia. Although forensic technicians are aware of the disputes among population geneticists, they use and endorse the relations established between genetics, ‘race’ and geography because these fit with common-sense notions of visible bodily difference and the regionalization of race in the Colombian nation. PMID:27480000

  18. Acetone facilitated DNA sampling from electrical tapes improves DNA recovery and enables latent fingerprints development.

    PubMed

    Feine, Ilan; Shpitzen, Moshe; Geller, Boris; Salmon, Eran; Peleg, Tsach; Roth, Jonathan; Gafny, Ron

    2017-07-01

    Electrical tapes (ETs) are a common component of improvised explosive devices (IEDs) used by terrorists or criminal organizations and represent a valuable forensic resource for DNA and latent fingerprints recovery. However, DNA recovery rates are typically low and usually below the minimal amount required for amplification. In addition, most DNA extraction methods are destructive and do not allow further latent fingerprints development. In the present study a cell culture based touch DNA model was used to demonstrate a two-step acetone-water DNA recovery protocol from ETs. This protocol involves only the adhesive side of the ET and increases DNA recovery rates by up to 70%. In addition, we demonstrated partially successful latent fingerprints development from the non-sticky side of the ETs. Taken together, this protocol maximizes the forensic examination of ETs and is recommended for routine casework processing. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Forensic trace DNA: a review

    PubMed Central

    2010-01-01

    DNA analysis is frequently used to acquire information from biological material to aid enquiries associated with criminal offences, disaster victim identification and missing persons investigations. As the relevance and value of DNA profiling to forensic investigations has increased, so too has the desire to generate this information from smaller amounts of DNA. Trace DNA samples may be defined as any sample which falls below recommended thresholds at any stage of the analysis, from sample detection through to profile interpretation, and can not be defined by a precise picogram amount. Here we review aspects associated with the collection, DNA extraction, amplification, profiling and interpretation of trace DNA samples. Contamination and transfer issues are also briefly discussed within the context of trace DNA analysis. Whilst several methodological changes have facilitated profiling from trace samples in recent years it is also clear that many opportunities exist for further improvements. PMID:21122102

  20. Which articles and which topics in the forensic sciences are most highly cited?

    PubMed

    Jones, A W

    2005-01-01

    Forensic science is a multidisciplinary field, which covers many branches of the pure, the applied and the biomedical sciences. Writing-up and publishing research findings helps to enhance the reputation of the investigators and the laboratories where the work was done. The number of times an article is cited in the reference lists of other articles is generally accepted as a mark of distinction. Indeed, citation analysis has become widely used in research assessment of individual scientists, university departments and entire nations. This article concerns the most highly cited papers published in the Journal of Forensic Sciences (JFS) between 1956 and 2005. These were identified with the help of Web-of-Science, which is the on-line version of Science Citation Index, produced by Thomson Institute for Scientific Information (Thomson ISI) with head offices in Philadelphia, USA. This database tracks, among other things, the annual citation records of articles published in several thousand scientific journals worldwide. Those JFS articles accumulating 50 or more citations were identified and rank-ordered according to the total number of citations. These articles were also evaluated according to the name of first author, the subject category of the article, the country of origin and the pattern of co-authorship. This search strategy located 46 articles cited between 50 and 292 times since they first appeared in print. The most highly cited paper by far was by Kasai, Nakamura and White (USA and Japan) concerning DNA profiling and the application of the polymerase chain reaction (PCR) in forensic science. Some forensic scientists appeared as first author on two to three highly cited articles, namely Wetli (USA), Budowle (USA) and Comey (USA). When the highly cited articles were sub-divided into subject category, 15 were identified as coming from toxicology, closely followed by criminalistics (14 articles), pathology (nine articles), physical anthropology (five articles), forensic psychiatry (two articles) and one from odontology. The number of co-authors on these highly cited articles ranged from one to nine and the names of some investigators appeared on as many as four highly cited papers. The vast majority of papers originated from US laboratories although five came from Japan, two each from Sweden and Canada and there was also a joint USA-Swiss collaboration. The Thompson ISI citation databases provide unique tools for tracking citations to individual articles and impact and citation records of scholarly journals.

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

    PubMed

    Ciavaglia, Sherryn; Linacre, Adrian

    2018-05-01

    Reptile species, and in particular snakes, are protected by national and international agreements yet are commonly handled illegally. To aid in the enforcement of such legislation, we report on the development of three 11-plex assays from the genome of the carpet python to type 24 loci of tetra-nucleotide and penta-nucleotide repeat motifs (pure, compound and complex included). The loci range in size between 70 and 550 bp. Seventeen of the loci are newly characterised with the inclusion of seven previously developed loci to facilitate cross-comparison with previous carpet python genotyping studies. Assays were optimised in accordance with human forensic profiling kits using one nanogram template DNA. Three loci are included in all three of the multiplex reactions as quality assurance markers, to ensure sample identity and genotyping accuracy is maintained across the three profiling assays. Allelic ladders have been developed for the three assays to ensure consistent and precise allele designation. A DNA reference database of allele frequencies is presented based on 249 samples collected from throughout the species native range. A small number of validation tests are conducted to demonstrate the utility of these multiplex assays. We suggest further appropriate validation tests that should be conducted prior to the application of the multiplex assays in criminal investigations involving carpet pythons. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. A review of bioinformatic methods for forensic DNA analyses.

    PubMed

    Liu, Yao-Yuan; Harbison, SallyAnn

    2018-03-01

    Short tandem repeats, single nucleotide polymorphisms, and whole mitochondrial analyses are three classes of markers which will play an important role in the future of forensic DNA typing. The arrival of massively parallel sequencing platforms in forensic science reveals new information such as insights into the complexity and variability of the markers that were previously unseen, along with amounts of data too immense for analyses by manual means. Along with the sequencing chemistries employed, bioinformatic methods are required to process and interpret this new and extensive data. As more is learnt about the use of these new technologies for forensic applications, development and standardization of efficient, favourable tools for each stage of data processing is being carried out, and faster, more accurate methods that improve on the original approaches have been developed. As forensic laboratories search for the optimal pipeline of tools, sequencer manufacturers have incorporated pipelines into sequencer software to make analyses convenient. This review explores the current state of bioinformatic methods and tools used for the analyses of forensic markers sequenced on the massively parallel sequencing (MPS) platforms currently most widely used. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Design, optimisation and preliminary validation of a human specific loop-mediated amplification assay for the rapid detection of human DNA at forensic crime scenes.

    PubMed

    Hird, H J; Brown, M K

    2017-11-01

    The identification of samples at a crime scene which require forensic DNA typing has been the focus of recent research interest. We propose a simple, but sensitive analysis system which can be deployed at a crime scene to identify crime scene stains as human or non-human. The proposed system uses the isothermal amplification of DNA in a rapid assay format, which returns results in as little as 30min from sampling. The assay system runs on the Genie II device, a proven in-field detection system which could be deployed at a crime scene. The results presented here demonstrate that the system was sufficiently specific and sensitive and was able to detect the presence of human blood, semen and saliva on mock forensic samples. Copyright © 2017. Published by Elsevier B.V.

  4. 15 CFR Supplement No. 8 to Part 742 - Self-Classification Report for Encryption Items

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... forensics (v) Cryptographic accelerator (vi) Data backup and recovery (vii) Database (viii) Disk/drive... (MAN) (xxii) Modem (xxiii) Network convergence or infrastructure n.e.s. (xxiv) Network forensics (xxv...

  5. 15 CFR Supplement No. 8 to Part 742 - Self-Classification Report for Encryption Items

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... forensics (v) Cryptographic accelerator (vi) Data backup and recovery (vii) Database (viii) Disk/drive... (MAN) (xxii) Modem (xxiii) Network convergence or infrastructure n.e.s. (xxiv) Network forensics (xxv...

  6. 15 CFR Supplement No. 8 to Part 742 - Self-Classification Report for Encryption Items

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... forensics (v) Cryptographic accelerator (vi) Data backup and recovery (vii) Database (viii) Disk/drive... (MAN) (xxii) Modem (xxiii) Network convergence or infrastructure n.e.s. (xxiv) Network forensics (xxv...

  7. 15 CFR Supplement No. 8 to Part 742 - Self-Classification Report for Encryption Items

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... forensics (v) Cryptographic accelerator (vi) Data backup and recovery (vii) Database (viii) Disk/drive... (MAN) (xxii) Modem (xxiii) Network convergence or infrastructure n.e.s. (xxiv) Network forensics (xxv...

  8. Forensic DNA phenotyping: Developing a model privacy impact assessment.

    PubMed

    Scudder, Nathan; McNevin, Dennis; Kelty, Sally F; Walsh, Simon J; Robertson, James

    2018-05-01

    Forensic scientists around the world are adopting new technology platforms capable of efficiently analysing a larger proportion of the human genome. Undertaking this analysis could provide significant operational benefits, particularly in giving investigators more information about the donor of genetic material, a particularly useful investigative lead. Such information could include predicting externally visible characteristics such as eye and hair colour, as well as biogeographical ancestry. This article looks at the adoption of this new technology from a privacy perspective, using this to inform and critique the application of a Privacy Impact Assessment to this emerging technology. Noting the benefits and limitations, the article develops a number of themes that would influence a model Privacy Impact Assessment as a contextual framework for forensic laboratories and law enforcement agencies considering implementing forensic DNA phenotyping for operational use. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. DNA methylation: the future of crime scene investigation?

    PubMed

    Gršković, Branka; Zrnec, Dario; Vicković, Sanja; Popović, Maja; Mršić, Gordan

    2013-07-01

    Proper detection and subsequent analysis of biological evidence is crucial for crime scene reconstruction. The number of different criminal acts is increasing rapidly. Therefore, forensic geneticists are constantly on the battlefield, trying hard to find solutions how to solve them. One of the essential defensive lines in the fight against the invasion of crime is relying on DNA methylation. In this review, the role of DNA methylation in body fluid identification and other DNA methylation applications are discussed. Among other applications of DNA methylation, age determination of the donor of biological evidence, analysis of the parent-of-origin specific DNA methylation markers at imprinted loci for parentage testing and personal identification, differentiation between monozygotic twins due to their different DNA methylation patterns, artificial DNA detection and analyses of DNA methylation patterns in the promoter regions of circadian clock genes are the most important ones. Nevertheless, there are still a lot of open chapters in DNA methylation research that need to be closed before its final implementation in routine forensic casework.

  10. Dental DNA fingerprinting in identification of human remains

    PubMed Central

    Girish, KL; Rahman, Farzan S; Tippu, Shoaib R

    2010-01-01

    The recent advances in molecular biology have revolutionized all aspects of dentistry. DNA, the language of life yields information beyond our imagination, both in health or disease. DNA fingerprinting is a tool used to unravel all the mysteries associated with the oral cavity and its manifestations during diseased conditions. It is being increasingly used in analyzing various scenarios related to forensic science. The technical advances in molecular biology have propelled the analysis of the DNA into routine usage in crime laboratories for rapid and early diagnosis. DNA is an excellent means for identification of unidentified human remains. As dental pulp is surrounded by dentin and enamel, which forms dental armor, it offers the best source of DNA for reliable genetic type in forensic science. This paper summarizes the recent literature on use of this technique in identification of unidentified human remains. PMID:21731342

  11. DNA Profiles from Fingerprint Lifts-Enhancing the Evidential Value of Fingermarks Through Successful DNA Typing.

    PubMed

    Subhani, Zuhaib; Daniel, Barbara; Frascione, Nunzianda

    2018-05-25

    This study evaluated the compatibility of the most common enhancement methods and lifting techniques with DNA profiling. Emphasis is placed on modern lifting techniques (i.e., gelatin lifters and Isomark™) and historical fingerprint lifts for which limited research has been previously conducted. A total of 180 fingerprints were deposited on a glass surface, enhanced, lifted, and processed for DNA typing. DNA could be extracted and profiled for all the powders and lifts tested and from both groomed fingerprints and natural prints with no significant difference in the percentage of profile recovered. DNA profiles could also be obtained from historical fingerprint lifts (79.2% of 72 lifts) with one or more alleles detected. These results demonstrate the compatibility between different powder/lift combinations and DNA profiling therefore augmenting the evidential value of fingerprints in forensic casework. © 2018 American Academy of Forensic Sciences.

  12. Microchip-based cell lysis and DNA extraction from sperm cells for application to forensic analysis.

    PubMed

    Bienvenue, Joan M; Duncalf, Natalie; Marchiarullo, Daniel; Ferrance, Jerome P; Landers, James P

    2006-03-01

    The current backlog of casework is among the most significant challenges facing crime laboratories at this time. While the development of next-generation microchip-based technology for expedited forensic casework analysis offers one solution to this problem, this will require the adaptation of manual, large-volume, benchtop chemistry to small volume microfluidic devices. Analysis of evidentiary materials from rape kits where semen or sperm cells are commonly found represents a unique set of challenges for on-chip cell lysis and DNA extraction that must be addressed for successful application. The work presented here details the development of a microdevice capable of DNA extraction directly from sperm cells for application to the analysis of sexual assault evidence. A variety of chemical lysing agents are assessed for inclusion in the extraction protocol and a method for DNA purification from sperm cells is described. Suitability of the extracted DNA for short tandem repeat (STR) analysis is assessed and genetic profiles shown. Finally, on-chip cell lysis methods are evaluated, with results from fluorescence visualization of cell rupture and DNA extraction from an integrated cell lysis and purification with subsequent STR amplification presented. A method for on-chip cell lysis and DNA purification is described, with considerations toward inclusion in an integrated microdevice capable of both differential cell sorting and DNA extraction. The results of this work demonstrate the feasibility of incorporating microchip-based cell lysis and DNA extraction into forensic casework analysis.

  13. [Whole Genome Sequencing of Human mtDNA Based on Ion Torrent PGM™ Platform].

    PubMed

    Cao, Y; Zou, K N; Huang, J P; Ma, K; Ping, Y

    2017-08-01

    To analyze and detect the whole genome sequence of human mitochondrial DNA (mtDNA) by Ion Torrent PGM™ platform and to study the differences of mtDNA sequence in different tissues. Samples were collected from 6 unrelated individuals by forensic postmortem examination, including chest blood, hair, costicartilage, nail, skeletal muscle and oral epithelium. Amplification of whole genome sequence of mtDNA was performed by 4 pairs of primer. Libraries were constructed with Ion Shear™ Plus Reagents kit and Ion Plus Fragment Library kit. Whole genome sequencing of mtDNA was performed using Ion Torrent PGM™ platform. Sanger sequencing was used to determine the heteroplasmy positions and the mutation positions on HVⅠ region. The whole genome sequence of mtDNA from all samples were amplified successfully. Six unrelated individuals belonged to 6 different haplotypes. Different tissues in one individual had heteroplasmy difference. The heteroplasmy positions and the mutation positions on HVⅠ region were verified by Sanger sequencing. After a consistency check by the Kappa method, it was found that the results of mtDNA sequence had a high consistency in different tissues. The testing method used in present study for sequencing the whole genome sequence of human mtDNA can detect the heteroplasmy difference in different tissues, which have good consistency. The results provide guidance for the further applications of mtDNA in forensic science. Copyright© by the Editorial Department of Journal of Forensic Medicine

  14. Review and future prospects for DNA barcoding methods in forensic palynology.

    PubMed

    Bell, Karen L; Burgess, Kevin S; Okamoto, Kazufusa C; Aranda, Roman; Brosi, Berry J

    2016-03-01

    Pollen can be a critical forensic marker in cases where determining geographic origin is important, including investigative leads, missing persons cases, and intelligence applications. However, its use has previously been limited by the need for a high level of specialization by expert palynologists, slow speeds of identification, and relatively poor taxonomic resolution (typically to the plant family or genus level). By contrast, identification of pollen through DNA barcoding has the potential to overcome all three of these limitations, and it may seem surprising that the method has not been widely implemented. Despite what might seem a straightforward application of DNA barcoding to pollen, there are technical issues that have delayed progress. However, recent developments of standard methods for DNA barcoding of pollen, along with improvements in high-throughput sequencing technology, have overcome most of these technical issues. Based on these recent methodological developments in pollen DNA barcoding, we believe that now is the time to start applying these techniques in forensic palynology. In this article, we discuss the potential for these methods, and outline directions for future research to further improve on the technology and increase its applicability to a broader range of situations. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Linkage disequilibrium matches forensic genetic records to disjoint genomic marker sets.

    PubMed

    Edge, Michael D; Algee-Hewitt, Bridget F B; Pemberton, Trevor J; Li, Jun Z; Rosenberg, Noah A

    2017-05-30

    Combining genotypes across datasets is central in facilitating advances in genetics. Data aggregation efforts often face the challenge of record matching-the identification of dataset entries that represent the same individual. We show that records can be matched across genotype datasets that have no shared markers based on linkage disequilibrium between loci appearing in different datasets. Using two datasets for the same 872 people-one with 642,563 genome-wide SNPs and the other with 13 short tandem repeats (STRs) used in forensic applications-we find that 90-98% of forensic STR records can be connected to corresponding SNP records and vice versa. Accuracy increases to 99-100% when ∼30 STRs are used. Our method expands the potential of data aggregation, but it also suggests privacy risks intrinsic in maintenance of databases containing even small numbers of markers-including databases of forensic significance.

  16. Analysis of European mtDNAs for recombination.

    PubMed

    Elson, J L; Andrews, R M; Chinnery, P F; Lightowlers, R N; Turnbull, D M; Howell, N

    2001-01-01

    The standard paradigm postulates that the human mitochondrial genome (mtDNA) is strictly maternally inherited and that, consequently, mtDNA lineages are clonal. As a result of mtDNA clonality, phylogenetic and population genetic analyses should therefore be free of the complexities imposed by biparental recombination. The use of mtDNA in analyses of human molecular evolution is contingent, in fact, on clonality, which is also a condition that is critical both for forensic studies and for understanding the transmission of pathogenic mtDNA mutations within families. This paradigm, however, has been challenged recently by Eyre-Walker and colleagues. Using two different tests, they have concluded that recombination has contributed to the distribution of mtDNA polymorphisms within the human population. We have assembled a database that comprises the complete sequences of 64 European and 2 African mtDNAs. When this set of sequences was analyzed using any of three measures of linkage disequilibrium, one of the tests of Eyre-Walker and colleagues, there was no evidence for mtDNA recombination. When their test for excess homoplasies was applied to our set of sequences, only a slight excess of homoplasies was observed. We discuss possible reasons that our results differ from those of Eyre-Walker and colleagues. When we take the various results together, our conclusion is that mtDNA recombination has not been sufficiently frequent during human evolution to overturn the standard paradigm.

  17. Extra-bodily DNA sampling by the police.

    PubMed

    Gans, Jeremy

    2013-12-01

    Forensic investigators have statutory powers to take DNA samples directly from suspects' bodies in certain circumstances but sometimes the powers fall short, legally or practically Police may then look for samples that have become separated from their suspects for one reason or another. No jurisdiction currently bars or even regulates this practice, which is instead loosely governed by laws on property, consent and evidence. This article argues that this lack of regulation undermines the entire system of forensic procedure laws.

  18. The forensic value of X-linked markers in mixed-male DNA analysis.

    PubMed

    He, HaiJun; Zha, Lagabaiyila; Cai, JinHong; Huang, Jian

    2018-05-04

    Autosomal genetic markers and Y chromosome markers have been widely applied in analysis of mixed stains at crime scenes by forensic scientists. However, true genotype combinations are often difficult to distinguish using autosomal markers when similar amounts of DNA are contributed by multiple donors. In addition, specific individuals cannot be determined by Y chromosomal markers because male relatives share the same Y chromosome. X-linked markers, possessing characteristics somewhere intermediate between autosomes and the Y chromosome, are less universally applied in criminal casework. In this paper, X markers are proposed to apply to male mixtures because their true genes can be more easily and accurately recognized than the decision of the genotypes of AS markers. In this study, an actual two-man mixed stain from a forensic case file and simulated male-mixed DNA were examined simultaneously with the X markers and autosomal markers. Finally, the actual mixture was separated successfully by the X markers, although it was unresolved by AS-STRs, and the separation ratio of the simulated mixture was much higher using Chr X tools than with AS methods. We believe X-linked markers provide significant advantages in individual discrimination of male mixtures that should be further applied to forensic work.

  19. Methodological approach to crime scene investigation: the dangers of technology

    NASA Astrophysics Data System (ADS)

    Barnett, Peter D.

    1997-02-01

    The visitor to any modern forensic science laboratory is confronted with equipment and processes that did not exist even 10 years ago: thermocyclers to allow genetic typing of nanogram amounts of DNA isolated from a few spermatozoa; scanning electron microscopes that can nearly automatically detect submicrometer sized particles of molten lead, barium and antimony produced by the discharge of a firearm and deposited on the hands of the shooter; and computers that can compare an image of a latent fingerprint with millions of fingerprints stored in the computer memory. Analysis of populations of physical evidence has permitted statistically minded forensic scientists to use Bayesian inference to draw conclusions based on a priori assumptions which are often poorly understood, irrelevant, or misleading. National commissions who are studying quality control in DNA analysis propose that people with barely relevant graduate degrees and little forensic science experience be placed in charge of forensic DNA laboratories. It is undeniable that high- tech has reversed some miscarriages of justice by establishing the innocence of a number of people who were imprisoned for years for crimes that they did not commit. However, this papers deals with the dangers of technology in criminal investigations.

  20. Development and validation of the AmpFℓSTR® Identifiler® Direct PCR Amplification Kit: a multiplex assay for the direct amplification of single-source samples.

    PubMed

    Wang, Dennis Y; Chang, Chien-Wei; Lagacé, Robert E; Oldroyd, Nicola J; Hennessy, Lori K

    2011-07-01

    The AmpFℓSTR(®) Identifiler(®) Direct PCR Amplification Kit is a new short tandem repeat multiplex assay optimized to allow the direct amplification of single-source blood and buccal samples on FTA(®) card without the need for sample purification and quantification. This multiplex assay has been validated according to the FBI/National Standards and SWGDAM guidelines. Validation results revealed that slight variations in primer concentration, master mix component concentration, and thermal cycling parameters did not affect the performance of the chemistry. The assay's sensitivity was demonstrated by amplifying known amounts of white blood cells spotted onto FTA(®) cards, and the assay's specificity was verified by establishing minimal cross-reactivity with nonhuman DNA. No effect on the age of the sample stored on the FTA(®) substrate was observed and full concordance was established in the population study. These findings of the validation study support the use of the Identifiler(®) Direct Kit for forensic standards and database samples genotyping. © 2011 American Academy of Forensic Sciences.

  1. Forensic validation of the PowerPlex® ESI 16 STR Multiplex and comparison of performance with AmpFlSTR® SGM Plus®.

    PubMed

    Tucker, Valerie C; Kirkham, Amanda J; Hopwood, Andrew J

    2012-05-01

    We describe the forensic validation of Promega's PowerPlex® European Standard Investigator 16 (ESI 16) multiplex kit and compare results generated with the AmpFlSTR® SGM Plus® (SGM+) multiplex. ESI 16 combines the loci contained within the SGM+ multiplex with five additional loci: D2S441, D10S1248, D22S1045, D1S1656, and D12S391. A relative reduction in amplicon size of the SGM+ loci facilitates an increased robustness and amplification success of these amplicons with degraded DNA samples. Tests performed herein supplement ESI 16 data published previously with sensitivity, profile quality, mock casework, inhibitor and mixture study data collected in our laboratories in alignment with our internal technical and quality guidelines and those issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), the DNA Advisory Board (DAB) and the DNA working group (DNAWG) of the European Network of Forensic Science Institutes (ENFSI). Full profiles were routinely generated from a fully heterozygous single source DNA template using 62.5 pg for ESI 16 and 500 pg for SGM+. This increase in sensitivity has a consequent effect on mixture analyses and the detection of minor mixture components. The improved PCR chemistry confers enhanced tolerance to high levels of laboratory prepared inhibitors compared with SGM+ results. In summary, our results demonstrate that the ESI 16 multiplex kit is more robust and sensitive compared with SGM+ and will be a suitable replacement system for the analysis of forensic DNA samples providing compliance with the European standard set of STR loci.

  2. Mitochondrial DNA heteroplasmy in the emerging field of massively parallel sequencing

    PubMed Central

    Just, Rebecca S.; Irwin, Jodi A.; Parson, Walther

    2015-01-01

    Long an important and useful tool in forensic genetic investigations, mitochondrial DNA (mtDNA) typing continues to mature. Research in the last few years has demonstrated both that data from the entire molecule will have practical benefits in forensic DNA casework, and that massively parallel sequencing (MPS) methods will make full mitochondrial genome (mtGenome) sequencing of forensic specimens feasible and cost-effective. A spate of recent studies has employed these new technologies to assess intraindividual mtDNA variation. However, in several instances, contamination and other sources of mixed mtDNA data have been erroneously identified as heteroplasmy. Well vetted mtGenome datasets based on both Sanger and MPS sequences have found authentic point heteroplasmy in approximately 25% of individuals when minor component detection thresholds are in the range of 10–20%, along with positional distribution patterns in the coding region that differ from patterns of point heteroplasmy in the well-studied control region. A few recent studies that examined very low-level heteroplasmy are concordant with these observations when the data are examined at a common level of resolution. In this review we provide an overview of considerations related to the use of MPS technologies to detect mtDNA heteroplasmy. In addition, we examine published reports on point heteroplasmy to characterize features of the data that will assist in the evaluation of future mtGenome data developed by any typing method. PMID:26009256

  3. Evaluation Of A Powder-Free DNA Extraction Method For Skeletal Remains.

    PubMed

    Harrel, Michelle; Mayes, Carrie; Gangitano, David; Hughes-Stamm, Sheree

    2018-02-07

    Bones are often recovered in forensic investigations, including missing persons and mass disasters. While traditional DNA extraction methods rely on grinding bone into powder prior to DNA purification, the TBone Ex buffer (DNA Chip Research Inc.) digests bone chips without powdering. In this study, six bones were extracted using the TBone Ex kit in conjunction with the PrepFiler ® BTA™ DNA extraction kit (Thermo Fisher Scientific) both manually and via an automated platform. Comparable amounts of DNA were recovered from a 50 mg bone chip using the TBone Ex kit and 50 mg of powdered bone with the PrepFiler ® BTA™ kit. However, automated DNA purification decreased DNA yield (p < 0.05). Nevertheless, short tandem repeat (STR) success was comparable across all methods tested. This study demonstrates that digestion of whole bone fragments is an efficient alternative to powdering bones for DNA extraction without compromising downstream STR profile quality. © 2018 American Academy of Forensic Sciences.

  4. DNA extraction and barcode identification of development stages of forensically important flies in the Czech Republic.

    PubMed

    Olekšáková, Tereza; Žurovcová, Martina; Klimešová, Vanda; Barták, Miroslav; Šuláková, Hana

    2018-04-01

    Several methods of DNA extraction, coupled with 'DNA barcoding' species identification, were compared using specimens from early developmental stages of forensically important flies from the Calliphoridae and Sarcophagidae families. DNA was extracted at three immature stages - eggs, the first instar larvae, and empty pupal cases (puparia) - using four different extraction methods, namely, one simple 'homemade' extraction buffer protocol and three commercial kits. The extraction conditions, including the amount of proteinase K and incubation times, were optimized. The simple extraction buffer method was successful for half of the eggs and for the first instar larval samples. The DNA Lego Kit and DEP-25 DNA Extraction Kit were useful for DNA extractions from the first instar larvae samples, and the DNA Lego Kit was also successful regarding the extraction from eggs. The QIAamp DNA mini kit was the most effective; the extraction was successful with regard to all sample types - eggs, larvae, and pupari.

  5. Trace DNA analysis: do you know what your neighbour is doing? A multi-jurisdictional survey.

    PubMed

    Raymond, Jennifer J; van Oorschot, Roland A H; Walsh, Simon J; Roux, Claude

    2008-01-01

    Since 1997 the analysis of DNA recovered from handled objects, or 'trace' DNA, has become routine and is frequently demanded from crime scene examinations. However, this analysis often produces unpredictable results. The factors affecting the recovery of full profiles are numerous, and include varying methods of collection and analysis. Communication between forensic laboratories in Australia and New Zealand has been limited in the past, due in some part to sheer distance. Because of its relatively small population and low number of forensic jurisdictions this region is in an excellent position to provide a collective approach. However, the protocols, training methods and research of each jurisdiction had not been widely exchanged. A survey was developed to benchmark the current practices involved in trace DNA analysis, aiming to provide information for training programs and research directions, and to identify factors contributing to the success or failure of the analysis. The survey was divided in to three target groups: crime scene officers, DNA laboratory scientists, and managers of these staff. In late 2004 surveys were sent to forensic organisations in every Australian jurisdiction and New Zealand. A total of 169 completed surveys were received with a return rate of 54%. Information was collated regarding sampling, extraction, amplification and analysis methods, contamination prevention, samples collected, success rates, personnel training and education, and concurrent fingerprinting. The data from the survey responses provided an insight into aspects of trace DNA analysis, from crime scene to interpretation and management. Several concerning factors arose from the survey. Results collation is a significant issue being identified as poor and differing widely, preventing inter-jurisdictional comparison and intra-jurisdictional assessment of both the processes and outputs. A second point of note is the widespread lack of refresher training and proficiency testing, with no set standard for initial training courses. A common theme to these and other issues was the need for a collective approach to training and methodology in trace DNA analysis. Trace DNA is a small fraction of the evidence available in current investigations, and parallels to these results and problems will no doubt be found in other forensic disciplines internationally. The significant point to be realised from this study is the need for effective communication lines between forensic organisations to ensure that best practice is followed, ideally with a cohesive pan-jurisdictional approach.

  6. Forensic and population genetic analysis of Xinjiang Uyghur population on 21 short tandem repeat loci of 6-dye GlobalFiler™ PCR Amplification kit.

    PubMed

    Zhang, Honghua; Xia, Mingying; Qi, Lijie; Dong, Lei; Song, Shuang; Ma, Teng; Yang, Shuping; Jin, Li; Li, Liming; Li, Shilin

    2016-05-01

    Estimating the allele frequencies and forensic statistical parameters of commonly used short tandem repeat (STR) loci of the Uyghur population, which is the fifth largest group in China, provides a more precise reference database for forensic investigation. The 6-dye GlobalFiler™ Express PCR Amplification kit incorporates 21 autosomal STRs, which have been proven that could provide reliable DNA typing results and enhance the power of discrimination. Here we analyzed the GlobalFiler STR loci on 1962 unrelated individuals from Chinese Uyghur population of Xinjiang, China. No significant deviations from Hardy-Weinberg equilibrium and linkage disequilibrium were detected within and between the GlobalFiler STR loci. SE33 showed the greatest power of discrimination in Uyghur population, whereas TPOX showed the lowest. The combined power of discrimination was 99.999999999999999999999998746%. No significant difference was observed between Uyghur and the other two Uyghur populations at all tested STRs, as well as Dai and Mongolian. Significant differences were only observed between Uyghur and other Chinese populations at TH01, as well as Central-South Asian at D13S317, East Asian at TH01 and VWA. The phylogenetic analysis showed that Uyghur is genetically close to Chinese populations, as well as East Asian and Central-South Asian. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Missing persons-missing data: the need to collect antemortem dental records of missing persons.

    PubMed

    Blau, Soren; Hill, Anthony; Briggs, Christopher A; Cordner, Stephen M

    2006-03-01

    The subject of missing persons is of great concern to the community with numerous associated emotional, financial, and health costs. This paper examines the forensic medical issues raised by the delayed identification of individuals classified as "missing" and highlights the importance of including dental data in the investigation of missing persons. Focusing on Australia, the current approaches employed in missing persons investigations are outlined. Of particular significance is the fact that each of the eight Australian states and territories has its own Missing Persons Unit that operates within distinct state and territory legislation. Consequently, there is a lack of uniformity within Australia about the legal and procedural framework within which investigations of missing persons are conducted, and the interaction of that framework with coronial law procedures. One of the main investigative problems in missing persons investigations is the lack of forensic medical, particularly, odontological input. Forensic odontology has been employed in numerous cases in Australia where identity is unknown or uncertain because of remains being skeletonized, incinerated, or partly burnt. The routine employment of the forensic odontologist to assist in missing person inquiries, has however, been ignored. The failure to routinely employ forensic odontology in missing persons inquiries has resulted in numerous delays in identification. Three Australian cases are presented where the investigation of individuals whose identity was uncertain or unknown was prolonged due to the failure to utilize the appropriate (and available) dental resources. In light of the outcomes of these cases, we suggest that a national missing persons dental records database be established for future missing persons investigations. Such a database could be easily managed between a coronial system and a forensic medical institute. In Australia, a national missing persons dental records database could be incorporated into the National Coroners Information System (NCIS) managed, on behalf of Australia's Coroners, by the Victorian Institute of Forensic Medicine. The existence of the NCIS would ensure operational collaboration in the implementation of the system and cost savings to Australian policing agencies involved in missing person inquiries. The implementation of such a database would facilitate timely and efficient reconciliation of clinical and postmortem dental records and have subsequent social and financial benefits.

  8. Introducing the Forensic Research/Reference on Genetics knowledge base, FROG-kb

    PubMed Central

    2012-01-01

    Background Online tools and databases based on multi-allelic short tandem repeat polymorphisms (STRPs) are actively used in forensic teaching, research, and investigations. The Fst value of each CODIS marker tends to be low across the populations of the world and most populations typically have all the common STRP alleles present diminishing the ability of these systems to discriminate ethnicity. Recently, considerable research is being conducted on single nucleotide polymorphisms (SNPs) to be considered for human identification and description. However, online tools and databases that can be used for forensic research and investigation are limited. Methods The back end DBMS (Database Management System) for FROG-kb is Oracle version 10. The front end is implemented with specific code using technologies such as Java, Java Servlet, JSP, JQuery, and GoogleCharts. Results We present an open access web application, FROG-kb (Forensic Research/Reference on Genetics-knowledge base, http://frog.med.yale.edu), that is useful for teaching and research relevant to forensics and can serve as a tool facilitating forensic practice. The underlying data for FROG-kb are provided by the already extensively used and referenced ALlele FREquency Database, ALFRED (http://alfred.med.yale.edu). In addition to displaying data in an organized manner, computational tools that use the underlying allele frequencies with user-provided data are implemented in FROG-kb. These tools are organized by the different published SNP/marker panels available. This web tool currently has implemented general functions possible for two types of SNP panels, individual identification and ancestry inference, and a prediction function specific to a phenotype informative panel for eye color. Conclusion The current online version of FROG-kb already provides new and useful functionality. We expect FROG-kb to grow and expand in capabilities and welcome input from the forensic community in identifying datasets and functionalities that will be most helpful and useful. Thus, the structure and functionality of FROG-kb will be revised in an ongoing process of improvement. This paper describes the state as of early June 2012. PMID:22938150

  9. DNA Commission of the International Society for Forensic Genetics: Recommendations on the validation of software programs performing biostatistical calculations for forensic genetics applications.

    PubMed

    Coble, M D; Buckleton, J; Butler, J M; Egeland, T; Fimmers, R; Gill, P; Gusmão, L; Guttman, B; Krawczak, M; Morling, N; Parson, W; Pinto, N; Schneider, P M; Sherry, S T; Willuweit, S; Prinz, M

    2016-11-01

    The use of biostatistical software programs to assist in data interpretation and calculate likelihood ratios is essential to forensic geneticists and part of the daily case work flow for both kinship and DNA identification laboratories. Previous recommendations issued by the DNA Commission of the International Society for Forensic Genetics (ISFG) covered the application of bio-statistical evaluations for STR typing results in identification and kinship cases, and this is now being expanded to provide best practices regarding validation and verification of the software required for these calculations. With larger multiplexes, more complex mixtures, and increasing requests for extended family testing, laboratories are relying more than ever on specific software solutions and sufficient validation, training and extensive documentation are of upmost importance. Here, we present recommendations for the minimum requirements to validate bio-statistical software to be used in forensic genetics. We distinguish between developmental validation and the responsibilities of the software developer or provider, and the internal validation studies to be performed by the end user. Recommendations for the software provider address, for example, the documentation of the underlying models used by the software, validation data expectations, version control, implementation and training support, as well as continuity and user notifications. For the internal validations the recommendations include: creating a validation plan, requirements for the range of samples to be tested, Standard Operating Procedure development, and internal laboratory training and education. To ensure that all laboratories have access to a wide range of samples for validation and training purposes the ISFG DNA commission encourages collaborative studies and public repositories of STR typing results. Published by Elsevier Ireland Ltd.

  10. More comprehensive forensic genetic marker analyses for accurate human remains identification using massively parallel DNA sequencing.

    PubMed

    Ambers, Angie D; Churchill, Jennifer D; King, Jonathan L; Stoljarova, Monika; Gill-King, Harrell; Assidi, Mourad; Abu-Elmagd, Muhammad; Buhmeida, Abdelbaset; Al-Qahtani, Mohammed; Budowle, Bruce

    2016-10-17

    Although the primary objective of forensic DNA analyses of unidentified human remains is positive identification, cases involving historical or archaeological skeletal remains often lack reference samples for comparison. Massively parallel sequencing (MPS) offers an opportunity to provide biometric data in such cases, and these cases provide valuable data on the feasibility of applying MPS for characterization of modern forensic casework samples. In this study, MPS was used to characterize 140-year-old human skeletal remains discovered at a historical site in Deadwood, South Dakota, United States. The remains were in an unmarked grave and there were no records or other metadata available regarding the identity of the individual. Due to the high throughput of MPS, a variety of biometric markers could be typed using a single sample. Using MPS and suitable forensic genetic markers, more relevant information could be obtained from a limited quantity and quality sample. Results were obtained for 25/26 Y-STRs, 34/34 Y SNPs, 166/166 ancestry-informative SNPs, 24/24 phenotype-informative SNPs, 102/102 human identity SNPs, 27/29 autosomal STRs (plus amelogenin), and 4/8 X-STRs (as well as ten regions of mtDNA). The Y-chromosome (Y-STR, Y-SNP) and mtDNA profiles of the unidentified skeletal remains are consistent with the R1b and H1 haplogroups, respectively. Both of these haplogroups are the most common haplogroups in Western Europe. Ancestry-informative SNP analysis also supported European ancestry. The genetic results are consistent with anthropological findings that the remains belong to a male of European ancestry (Caucasian). Phenotype-informative SNP data provided strong support that the individual had light red hair and brown eyes. This study is among the first to genetically characterize historical human remains with forensic genetic marker kits specifically designed for MPS. The outcome demonstrates that substantially more genetic information can be obtained from the same initial quantities of DNA as that of current CE-based analyses.

  11. Next generation sequencing (NGS): a golden tool in forensic toolkit.

    PubMed

    Aly, S M; Sabri, D M

    The DNA analysis is a cornerstone in contemporary forensic sciences. DNA sequencing technologies are powerful tools that enrich molecular sciences in the past based on Sanger sequencing and continue to glowing these sciences based on Next generation sequencing (NGS). Next generation sequencing has excellent potential to flourish and increase the molecular applications in forensic sciences by jumping over the pitfalls of the conventional method of sequencing. The main advantages of NGS compared to conventional method that it utilizes simultaneously a large number of genetic markers with high-resolution of genetic data. These advantages will help in solving several challenges such as mixture analysis and dealing with minute degraded samples. Based on these new technologies, many markers could be examined to get important biological data such as age, geographical origins, tissue type determination, external visible traits and monozygotic twins identification. It also could get data related to microbes, insects, plants and soil which are of great medico-legal importance. Despite the dozens of forensic research involving NGS, there are requirements before using this technology routinely in forensic cases. Thus, there is a great need to more studies that address robustness of these techniques. Therefore, this work highlights the applications of forensic sciences in the era of massively parallel sequencing.

  12. Theory and applications of the polymerase chain reaction.

    PubMed

    Remick, D G; Kunkel, S L; Holbrook, E A; Hanson, C A

    1990-04-01

    The polymerase chain reaction (PCR) is a newly developed molecular biology technique that can significantly amplify DNA or RNA. The process consists of repetitive cycles of specific DNA synthesis, defined by short stretches of preselected DNA. With each cycle, there is a doubling of the final, desired DNA product such that a million-fold amplification is possible. This powerful method has numerous applications in diagnostic pathology, especially in the fields of microbiology, forensic science, and hematology. The PCR may be used to directly detect viral DNA, which may facilitate the diagnosis of acquired immune deficiency syndrome (AIDS) or other viral diseases. PCR amplification of DNA allows detection of specific sequences from extremely small samples, such as with forensic material. In hematology, PCR may help in the diagnosis of hemoglobinopathies or of neoplastic disorders by documenting chromosomal translocations. The new PCR opens exciting new avenues for diagnostic pathology using this new technology.

  13. Forensic DNA expertise of incest in early period of pregnancy.

    PubMed

    Jakovski, Zlatko; Jankova, Renata; Nikolova, Ksenija; Spasevska, Liljana; Jovanovic, Rubens; Janeska, Biljana

    2011-01-01

    Proving incest from tissue obtained by abortion early in pregnancy can be a challenge. Problems include the small quantity of embryonic tissue in the products of conception, and the mixing of DNA from mother and embryo. In many cases, this amorphous material cannot be grossly segregated into maternal and fetal components. Thus, morphological discrimination requires microscopy to select relevant tissue particles from which DNA can be typed. This combination of methods is reliable and efficient. In this article, we present two cases of incest discovered by examination of products of conception. Copyright © 2010 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  14. Basic Concepts, Current Practices and Available Resources for Forensic Investigations on Pavements

    DOT National Transportation Integrated Search

    1997-09-01

    The purpose of the project, entitled Development of a Methodology for Identifying Pavement Design and Construction Data Needed to Support a Forensic Investigation," is to develop a database containing information useful in identifying the premature f...

  15. Developmental validation of a Cannabis sativa STR multiplex system for forensic analysis.

    PubMed

    Howard, Christopher; Gilmore, Simon; Robertson, James; Peakall, Rod

    2008-09-01

    A developmental validation study based on recommendations of the Scientific Working Group on DNA Analysis Methods (SWGDAM) was conducted on a multiplex system of 10 Cannabis sativa short tandem repeat loci. Amplification of the loci in four multiplex reactions was tested across DNA from dried root, stem, and leaf sources, and DNA from fresh, frozen, and dried leaf tissue with a template DNA range of 10.0-0.01 ng. The loci were amplified and scored consistently for all DNA sources when DNA template was in the range of 10.0-1.0 ng. Some allelic dropout and PCR failure occurred in reactions with lower template DNA amounts. Overall, amplification was best using 10.0 ng of template DNA from dried leaf tissue indicating that this is the optimal source material. Cross species amplification was observed in Humulus lupulus for three loci but there was no allelic overlap. This is the first study following SWGDAM validation guidelines to validate short tandem repeat markers for forensic use in plants.

  16. Evaluation of Skin Surface as an Alternative Source of Reference DNA Samples: A Pilot Study.

    PubMed

    Albujja, Mohammed H; Bin Dukhyil, Abdul Aziz; Chaudhary, Abdul Rauf; Kassab, Ahmed Ch; Refaat, Ahmed M; Babu, Saranya Ramesh; Okla, Mohammad K; Kumar, Sachil

    2018-01-01

    An acceptable area for collecting DNA reference sample is a part of the forensic DNA analysis development. The aim of this study was to evaluate skin surface cells (SSC) as an alternate source of reference DNA sample. From each volunteer (n = 10), six samples from skin surface areas (forearm and fingertips) and two traditional samples (blood and buccal cells) were collected. Genomic DNA was extracted and quantified then genotyped using standard techniques. The highest DNA concentration of SSC samples was collected using the tape/forearm method of collection (2.1 ng/μL). Cotton swabs moistened with ethanol yielded higher quantities of DNA than swabs moistened with salicylic acid, and it gave the highest percentage of full STR profiles (97%). This study supports the use of SSC as a noninvasive sampling technique and as a extremely useful source of DNA reference samples among certain cultures where the use of buccal swabs can be considered socially unacceptable. © 2017 American Academy of Forensic Sciences.

  17. A Simple and Efficient Method of Extracting DNA from Aged Bones and Teeth.

    PubMed

    Liu, Qiqi; Liu, Liyan; Zhang, Minli; Zhang, Qingzhen; Wang, Qiong; Ding, Xiaoran; Shao, Liting; Zhou, Zhe; Wang, Shengqi

    2018-05-01

    DNA is often difficult to extract from old bones and teeth due to low levels of DNA and high levels of degradation. This study established a simple yet efficient method for extracting DNA from 20 aged bones and teeth (approximately 60 years old). Based on the concentration and STR typing results, the new method of DNA extraction (OM) developed in this study was compared with the PrepFiler™ BTA Forensic DNA Extraction Kit (BM). The total amount of DNA extracted using the OM method was not significantly different from that extracted using the commercial kit (p > 0.05). However, the number of STR loci detected was significantly higher in the samples processed using the OM method than using the BM method (p < 0.05). This study aimed to establish a DNA extraction method for aged bones and teeth to improve the detection rate of STR typing and reduce costs compared to the BM technique. © 2017 American Academy of Forensic Sciences.

  18. Elimination of bioweapons agents from forensic samples during extraction of human DNA.

    PubMed

    Timbers, Jason; Wilkinson, Della; Hause, Christine C; Smith, Myron L; Zaidi, Mohsin A; Laframboise, Denis; Wright, Kathryn E

    2014-11-01

    Collection of DNA for genetic profiling is a powerful means for the identification of individuals responsible for crimes and terrorist acts. Biologic hazards, such as bacteria, endospores, toxins, and viruses, could contaminate sites of terrorist activities and thus could be present in samples collected for profiling. The fate of these hazards during DNA isolation has not been thoroughly examined. Our goals were to determine whether the DNA extraction process used by the Royal Canadian Mounted Police eliminates or neutralizes these agents and if not, to establish methods that render samples safe without compromising the human DNA. Our results show that bacteria, viruses, and toxins were reduced to undetectable levels during DNA extraction, but endospores remained viable. Filtration of samples after DNA isolation eliminated viable spores from the samples but left DNA intact. We also demonstrated that contamination of samples with some bacteria, endospores, and toxins for longer than 1 h compromised the ability to complete genetic profiling. © 2014 American Academy of Forensic Sciences.

  19. Home - Virginia Department of Forensic Science

    Science.gov Websites

    Procedure Manuals Training Manuals Digital & Multimedia Evidence Computer Analysis Video Analysis Procedure Manual Training Manual FAQ Updates Firearms & Toolmarks Procedure Manuals Training Manuals Forensic Biology Procedure Manuals Training Manuals Familial Searches Post-Conviction DNA Issues FAQ

  20. Amplification volume reduction on DNA database samples using FTA™ Classic Cards.

    PubMed

    Wong, Hang Yee; Lim, Eng Seng Simon; Tan-Siew, Wai Fun

    2012-03-01

    The DNA forensic community always strives towards improvements in aspects such as sensitivity, robustness, and efficacy balanced with cost efficiency. Therefore our laboratory decided to study the feasibility of PCR amplification volume reduction using DNA entrapped in FTA™ Classic Card and to bring cost savings to the laboratory. There were a few concerns the laboratory needed to address. First, the kinetics of the amplification reaction could be significantly altered. Second, an increase in sensitivity might affect interpretation due to increased stochastic effects even though they were pristine samples. Third, statics might cause FTA punches to jump out of its allocated well into another thus causing sample-to-sample contamination. Fourth, the size of the punches might be too small for visual inspection. Last, there would be a limit to the extent of volume reduction due to evaporation and the possible need of re-injection of samples for capillary electrophoresis. The laboratory had successfully optimized a reduced amplification volume of 10 μL for FTA samples. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  1. Human autosomal DNA and X chromosome STR profiles obtained from Chrysomya albiceps (Diptera: Calliphoridae) larvae used as a biological trace.

    PubMed

    Oliveira, T C; Santos, A B R; Rabelo, K C N; Souza, C A; Santos, S M; Crovella, S

    2016-11-03

    The use of insects to answer questions in criminal investigations, as well as a combination of forensic genetic techniques to obtain human DNA from the organisms, especially necrophagous dipterians, have gained ground in recent decades among researchers and professionals in this area. The objective of our study was to evaluate and compare two methods of human DNA extraction, commonly used for forensic samples, to obtain human autosomal DNA and X chromosome short tandem repeat profiles from the digestive tract of Chrysomya albiceps (Diptera: Calliphoridae) larvae. Immature specimens were collected from corpses at the Institute of Forensic Medicine of Pernambuco and raised in bovine ground meat to allow stabilization of the colony. Groups of larvae in the third instar were provided with bovine ground meat plus human blood for 48 h, dissected, and then subjected to DNA extraction. DNA was extracted using two methods: a DNA IQ™ kit and a phenol-chloroform method. Genomic DNA was amplified using AmpFℓSTR ® Identifiler ® Plus PCR and Argus-X-12 ® kits, and samples were sequenced to determine if the two extraction techniques generated reliable profiles that were compatible with a reference sample. The existence of comparable profiles from both techniques demonstrates the usefulness of dipteran larvae for obtaining human DNA from corpses, which can be further used to correlate genetic profiles in a crime scene when other traces are not available. However, several variables still require revision; thus, the technique should be further investigated for its validity, security, and, in particular, its reproducibility.

  2. Development and validation of a Database Forensic Metamodel (DBFM)

    PubMed Central

    Al-dhaqm, Arafat; Razak, Shukor; Othman, Siti Hajar; Ngadi, Asri; Ahmed, Mohammed Nazir; Ali Mohammed, Abdulalem

    2017-01-01

    Database Forensics (DBF) is a widespread area of knowledge. It has many complex features and is well known amongst database investigators and practitioners. Several models and frameworks have been created specifically to allow knowledge-sharing and effective DBF activities. However, these are often narrow in focus and address specified database incident types. We have analysed 60 such models in an attempt to uncover how numerous DBF activities are really public even when the actions vary. We then generate a unified abstract view of DBF in the form of a metamodel. We identified, extracted, and proposed a common concept and reconciled concept definitions to propose a metamodel. We have applied a metamodelling process to guarantee that this metamodel is comprehensive and consistent. PMID:28146585

  3. Review: Properties of sperm and seminal fluid, informed by research on reproduction and contraception.

    PubMed

    Cotton, Robin W; Fisher, Matthew B

    2015-09-01

    Forensic DNA testing is grounded in molecular biology and population genetics. The technologies that were the basis of restriction length polymorphism testing (RFLP) have given way to PCR based technologies. While PCR has been the pillar of short tandem repeat (STR) methods and will continue to be used as DNA sequencing and analysis of single nucleotide polymorphisms (SNPs) are introduced into human identification, the molecular biology techniques in use today represent significant advances since the introduction of STR testing. Large forensic laboratories with dedicated research teams and forensic laboratories which are part of academic institutions have the resources to keep track of advances which can then be considered for further research or incorporated into current testing methods. However, many laboratories have limited ability to keep up with research advances outside of the immediate area of forensic science and may not have access to a large university library systems. This review focuses on filling this gap with respect to areas of research that intersect with selected methods used in forensic biology. The review summarizes information collected from several areas of the scientific literature where advances in molecular biology have produced information relevant to DNA analysis of sexual assault evidence and methods used in presumptive and confirmatory identification of semen. Older information from the literature is also included where this information may not be commonly known and is relevant to current methods. The topics selected highlight (1) information from applications of proteomics to sperm biology and human reproduction, (2) seminal fluid proteins and prostate cancer diagnostics, (3) developmental biology of sperm from the fertility literature and (4) areas where methods are common to forensic analysis and research in contraceptive use and monitoring. Information and progress made in these areas coincide with the research interests of forensic biology and cross-talk between these disciplines may benefit both. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  4. GrigoraSNPs: Optimized Analysis of SNPs for DNA Forensics.

    PubMed

    Ricke, Darrell O; Shcherbina, Anna; Michaleas, Adam; Fremont-Smith, Philip

    2018-04-16

    High-throughput sequencing (HTS) of single nucleotide polymorphisms (SNPs) enables additional DNA forensic capabilities not attainable using traditional STR panels. However, the inclusion of sets of loci selected for mixture analysis, extended kinship, phenotype, biogeographic ancestry prediction, etc., can result in large panel sizes that are difficult to analyze in a rapid fashion. GrigoraSNP was developed to address the allele-calling bottleneck that was encountered when analyzing SNP panels with more than 5000 loci using HTS. GrigoraSNPs uses a MapReduce parallel data processing on multiple computational threads plus a novel locus-identification hashing strategy leveraging target sequence tags. This tool optimizes the SNP calling module of the DNA analysis pipeline with runtimes that scale linearly with the number of HTS reads. Results are compared with SNP analysis pipelines implemented with SAMtools and GATK. GrigoraSNPs removes a computational bottleneck for processing forensic samples with large HTS SNP panels. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

  5. [Determination of Hair Shafts by InnoTyper® 21 Kit].

    PubMed

    Li, F; Zhang, M; Wang, Y X; Shui, J J; Yan, M; Jin, X P; Zhu, X J

    2017-12-01

    To explore the application value of InnoTyper® 21 kit in forensic practice. Samples of hair shafts and saliva were collected from 8 unrelated individuals. Template DNA was extracted by AutoMate Express™ forensic DNA automatic extraction system. DNA was amplified by InnoTyper® 21 kit and AmpFℓSTR™ Identifiler™ Plus kit, respectively, and then the results were compared. After the amplification by InnoTyper® 21 kit, complete specific genotyping could be detected from the saliva samples, and the peak value of genotyping profiles of hair shafts without sheath cells was 57-1 219 RFU. Allelic gene deletion could be found sometimes. When amplified by AmpFℓSTR™ Identifiler™ Plus kit, complete specific genotyping could be detected from the saliva samples, and the specific fragment was not detected in hair shafts without sheath cells. The InnoTyper® 21 kit has certain application value in the cases of hair shafts without sheath cells. Copyright© by the Editorial Department of Journal of Forensic Medicine

  6. An instrument for automated purification of nucleic acids from contaminated forensic samples

    PubMed Central

    Broemeling, David J; Pel, Joel; Gunn, Dylan C; Mai, Laura; Thompson, Jason D; Poon, Hiron; Marziali, Andre

    2008-01-01

    Forensic crime scene sample analysis, by its nature, often deals with samples in which there are low amounts of nucleic acids, on substrates that often lead to inhibition of subsequent enzymatic reactions such as PCR amplification for STR profiling. Common substrates include denim from blue jeans, which yields indigo dye as a PCR inhibitor, and soil, which yields humic substances as inhibitors. These inhibitors frequently co-extract with nucleic acids in standard column or bead-based preps, leading to frequent failure of STR profiling. We present a novel instrument for DNA purification of forensic samples that is capable of highly effective concentration of nucleic acids from soil particulates, fabric, and other complex samples including solid components. The novel concentration process, known as SCODA, is inherently selective for long charged polymers such as DNA, and therefore is able to effectively reject known contaminants. We present an automated sample preparation instrument based on this process, and preliminary results based on mock forensic samples. PMID:18438455

  7. Forensic DNA typing from teeth using demineralized root tips.

    PubMed

    Corrêa, Heitor Simões Dutra; Pedro, Fabio Luis Miranda; Volpato, Luiz Evaristo Ricci; Pereira, Thiago Machado; Siebert Filho, Gilberto; Borges, Álvaro Henrique

    2017-11-01

    Teeth are widely used samples in forensic human genetic identification due to their persistence and practical sampling and processing. Their processing, however, has changed very little in the last 20 years, usually including powdering or pulverization of the tooth. The objective of this study was to present demineralized root tips as DNA sources while, at the same time, not involving powdering the samples or expensive equipment for teeth processing. One to five teeth from each of 20 unidentified human bodies recovered from midwest Brazil were analyzed. Whole teeth were demineralized in EDTA solution with daily solution change. After a maximum of approximately seven days, the final millimeters of the root tip was excised. This portion of the sample was used for DNA extraction through a conventional organic protocol. DNA quantification and STR amplification were performed using commercial kits followed by capillary electrophoresis on 3130 or 3500 genetic analyzers. For 60% of the unidentified bodies (12 of 20), a full genetic profile was obtained from the extraction of the first root tip. By the end of the analyses, full genetic profiles were obtained for 85% of the individuals studied, of which 80% were positively identified. This alternative low-tech approach for postmortem teeth processing is capable of extracting DNA in sufficient quantity and quality for forensic casework, showing that root tips are viable nuclear DNA sources even after demineralization. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Simultaneous analysis of nuclear and mitochondrial DNA, mRNA and miRNA from backspatter from inside parts of firearms generated by shots at "triple contrast" doped ballistic models.

    PubMed

    Grabmüller, Melanie; Schyma, Christian; Euteneuer, Jan; Madea, Burkhard; Courts, Cornelius

    2015-09-01

    When a firearm projectile hits a biological target a spray of biological material (e.g., blood and tissue fragments) can be propelled from the entrance wound back towards the firearm. This phenomenon has become known as "backspatter" and if caused by contact shots or shots from short distances traces of backspatter may reach, consolidate on, and be recovered from, the inside surfaces of the firearm. Thus, a comprehensive investigation of firearm-related crimes must not only comprise of wound ballistic assessment but also backspatter analysis, and may even take into account potential correlations between these emergences. The aim of the present study was to evaluate and expand the applicability of the "triple contrast" method by probing its compatibility with forensic analysis of nuclear and mitochondrial DNA and the simultaneous investigation of co-extracted mRNA and miRNA from backspatter collected from internal components of different types of firearms after experimental shootings. We demonstrate that "triple contrast" stained biological samples collected from the inside surfaces of firearms are amenable to forensic co-analysis of DNA and RNA and permit sequence analysis of the entire mtDNA displacement-loop, even for "low template" DNA amounts that preclude standard short tandem repeat DNA analysis. Our findings underscore the "triple contrast" method's usefulness as a research tool in experimental forensic ballistics.

  9. ESDA®-Lite collection of DNA from latent fingerprints on documents.

    PubMed

    Plaza, Dane T; Mealy, Jamia L; Lane, J Nicholas; Parsons, M Neal; Bathrick, Abigail S; Slack, Donia P

    2015-05-01

    The ability to detect and non-destructively collect biological samples for DNA processing would benefit the forensic community by preserving the physical integrity of evidentiary items for more thorough evaluations by other forensic disciplines. The Electrostatic Detection Apparatus (ESDA®) was systemically evaluated for its ability to non-destructively collect DNA from latent fingerprints deposited on various paper substrates for short tandem repeat (STR) DNA profiling. Fingerprints were deposited on a variety of paper substrates that included resume paper, cotton paper, magazine paper, currency, copy paper, and newspaper. Three DNA collection techniques were performed: ESDA collection, dry swabbing, and substrate cutting. Efficacy of each collection technique was evaluated by the quantity of DNA present in each sample and the percent profile generated by each sample. Both the ESDA and dry swabbing non-destructive sampling techniques outperformed the destructive methodology of substrate cutting. A greater number of full profiles were generated from samples collected with the non-destructive dry swabbing collection technique than were generated from samples collected with the ESDA; however, the ESDA also allowed the user to visualize the area of interest while non-destructively collecting the biological material. The ability to visualize the biological material made sampling straightforward and eliminated the need for numerous, random swabbings/cuttings. Based on these results, the evaluated non-destructive ESDA collection technique has great potential for real-world forensic implementation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. The U.S. national nuclear forensics library, nuclear materials information program, and data dictionary

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lamont, Stephen Philip; Brisson, Marcia; Curry, Michael

    2011-02-17

    Nuclear forensics assessments to determine material process history requires careful comparison of sample data to both measured and modeled nuclear material characteristics. Developing centralized databases, or nuclear forensics libraries, to house this information is an important step to ensure all relevant data will be available for comparison during a nuclear forensics analysis and help expedite the assessment of material history. The approach most widely accepted by the international community at this time is the implementation of National Nuclear Forensics libraries, which would be developed and maintained by individual nations. This is an attractive alternative toan international database since it providesmore » an understanding that each country has data on materials produced and stored within their borders, but eliminates the need to reveal any proprietary or sensitive information to other nations. To support the concept of National Nuclear Forensics libraries, the United States Department of Energy has developed a model library, based on a data dictionary, or set of parameters designed to capture all nuclear forensic relevant information about a nuclear material. Specifically, information includes material identification, collection background and current location, analytical laboratories where measurements were made, material packaging and container descriptions, physical characteristics including mass and dimensions, chemical and isotopic characteristics, particle morphology or metallurgical properties, process history including facilities, and measurement quality assurance information. While not necessarily required, it may also be valuable to store modeled data sets including reactor burn-up or enrichment cascade data for comparison. It is fully expected that only a subset of this information is available or relevant to many materials, and much of the data populating a National Nuclear Forensics library would be process analytical or material accountability measurement data as opposed to a complete forensic analysis of each material in the library.« less

  11. Role of forensic pathologists in mass disasters.

    PubMed

    Schuliar, Yves; Knudsen, Peter Juel Thiis

    2012-06-01

    The forensic pathologist has always had a central role in the identification of the dead in every day practice, in accidents, and in disasters involving hundreds or thousands of victims. This role has changed in recent years, as advances in forensic odontology, genetics and anthropology have improved the chances of identifying victims beyond recognition. According to the Interpol DVI Guide, fingerprints, dental examination and DNA are the primary identifiers, and this has given new emphasis to the role of the forensic pathologist as the leader of a multidisciplinary team of experts in a disaster situation, based on his or her qualifications and the experience gained from doing the same work in the everyday situation of an institute of forensic medicine.

  12. GOVERNING GENETIC DATABASES: COLLECTION, STORAGE AND USE

    PubMed Central

    Gibbons, Susan M.C.; Kaye, Jane

    2008-01-01

    This paper provides an introduction to a collection of five papers, published as a special symposium journal issue, under the title: “Governing Genetic Databases: Collection, Storage and Use”. It begins by setting the scene, to provide a backdrop and context for the papers. It describes the evolving scientific landscape around genetic databases and genomic research, particularly within the biomedical and criminal forensic investigation fields. It notes the lack of any clear, coherent or coordinated legal governance regime, either at the national or international level. It then identifies and reflects on key cross-cutting issues and themes that emerge from the five papers, in particular: terminology and definitions; consent; special concerns around population genetic databases (biobanks) and forensic databases; international harmonisation; data protection; data access; boundary-setting; governance; and issues around balancing individual interests against public good values. PMID:18841252

  13. "The devil's in the detail": Release of an expanded, enhanced and dynamically revised forensic STR Sequence Guide.

    PubMed

    Phillips, C; Gettings, K Butler; King, J L; Ballard, D; Bodner, M; Borsuk, L; Parson, W

    2018-05-01

    The STR sequence template file published in 2016 as part of the considerations from the DNA Commission of the International Society for Forensic Genetics on minimal STR sequence nomenclature requirements, has been comprehensively revised and audited using the latest GRCh38 genome assembly. The list of forensic STRs characterized was expanded by including supplementary autosomal, X- and Y-chromosome microsatellites in less common use for routine DNA profiling, but some likely to be adopted in future massively parallel sequencing (MPS) STR panels. We outline several aspects of sequence alignment and annotation that required care and attention to detail when comparing sequences to GRCh37 and GRCh38 assemblies, as well as the necessary matching of MPS-based allele descriptions to previously established repeat region structures described in initial sequencing studies of the less well known forensic STRs. The revised sequence guide is now available in a dynamically updated FTP format from the STRidER website with a date-stamped change log to allow users to explore their own MPS data with the most up-to-date forensic STR sequence information compiled in a simple guide. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Cytochrome b based genetic differentiation of Indian wild pig (Sus scrofa cristatus) and domestic pig (Sus scrofa domestica) and its use in wildlife forensics.

    PubMed

    Gupta, Sandeep Kumar; Kumar, Ajit; Hussain, Syed Ainul; Vipin; Singh, Lalji

    2013-06-01

    The Indian wild pig (Sus scrofa cristatus) is a protected species and listed in the Indian Wildlife (Protection) Act, 1972. The wild pig is often hunted illegally and sold in market as meat warranting punishment under law. To avoid confusion in identification of these two subspecies during wildlife forensic examinations, we describe genetic differentiation of Indian wild and domestic pigs using a molecular technique. Analysis of sequence generated from the partial fragment (421bp) of mitochondrial DNA (mtDNA) cytochrome b (Cyt b) gene exhibited unambiguous (>3%) genetic variation between Indian wild and domestic pigs. We observed nine forensically informative nucleotide sequence (FINS) variations between Indian wild and domestic pigs. The overall genetic variation described in this study is helpful in forensic identification of the biological samples of wild and domestic pigs. It also helped in differentiating the Indian wild pig from other wild pig races. This study indicates that domestic pigs in India are not descendent of the Indian wild pig, however; they are closer to the other wild pig races found in Asia and Europe. Copyright © 2012 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

  15. Direct PCR Improves the Recovery of DNA from Various Substrates.

    PubMed

    Templeton, Jennifer E L; Taylor, Duncan; Handt, Oliva; Skuza, Pawel; Linacre, Adrian

    2015-11-01

    This study reports on the comparison of a standard extraction process with the direct PCR approach of processing low-level DNA swabs typical in forensic investigations. Varying concentrations of control DNA were deposited onto three commonly encountered substrates, brass, plastic, and glass, left to dry, and swabbed using premoistened DNA-free nylon FLOQswabs(™) . Swabs (n = 90) were either processed using the DNA IQ(™) kit or, for direct PCR, swab fibers (~2 mm(2) ) were added directly to the PCR with no prior extraction. A significant increase in the height of the alleles (p < 0.005) was observed when using the direct PCR approach over the extraction methodology when controlling for surface type and mass of DNA deposited. The findings indicate the potential use of direct PCR for increasing the PCR product obtained from low-template DNA samples in addition to minimizing contamination and saving resources. © 2015 American Academy of Forensic Sciences.

  16. Modified midi- and mini-multiplex PCR systems for mitochondrial DNA control region sequence analysis in degraded samples.

    PubMed

    Kim, Na Young; Lee, Hwan Young; Park, Sun Joo; Yang, Woo Ick; Shin, Kyoung-Jin

    2013-05-01

    Two multiplex polymerase chain reaction (PCR) systems (Midiplex and Miniplex) were developed for the amplification of the mitochondrial DNA (mtDNA) control region, and the efficiencies of the multiplexes for amplifying degraded DNA were validated using old skeletal remains. The Midiplex system consisted of two multiplex PCRs to amplify six overlapping amplicons ranging in length from 227 to 267 bp. The Miniplex system consisted of three multiplex PCRs to amplify 10 overlapping short amplicons ranging in length from 142 to 185 bp. Most mtDNA control region sequences of several 60-year-old and 400-500-year-old skeletal remains were successfully obtained using both PCR systems and consistent with those previously obtained by monoplex amplification. The multiplex system consisting of smaller amplicons is effective for mtDNA sequence analyses of ancient and forensic degraded samples, saving time, cost, and the amount of DNA sample consumed during analysis. © 2013 American Academy of Forensic Sciences.

  17. Evaluation of four commercial quantitative real-time PCR kits with inhibited and degraded samples.

    PubMed

    Holmes, Amy S; Houston, Rachel; Elwick, Kyleen; Gangitano, David; Hughes-Stamm, Sheree

    2018-05-01

    DNA quantification is a vital step in forensic DNA analysis to determine the optimal input amount for DNA typing. A quantitative real-time polymerase chain reaction (qPCR) assay that can predict DNA degradation or inhibitors present in the sample prior to DNA amplification could aid forensic laboratories in creating a more streamlined and efficient workflow. This study compares the results from four commercial qPCR kits: (1) Investigator® Quantiplex® Pro Kit, (2) Quantifiler® Trio DNA Quantification Kit, (3) PowerQuant® System, and (4) InnoQuant® HY with high molecular weight DNA, low template samples, degraded samples, and DNA spiked with various inhibitors.The results of this study indicate that all kits were comparable in accurately predicting quantities of high quality DNA down to the sub-picogram level. However, the InnoQuant(R) HY kit showed the highest precision across the DNA concentration range tested in this study. In addition, all kits performed similarly with low concentrations of forensically relevant PCR inhibitors. However, in general, the Investigator® Quantiplex® Pro Kit was the most tolerant kit to inhibitors and provided the most accurate quantification results with higher concentrations of inhibitors (except with salt). PowerQuant® and InnoQuant® HY were the most sensitive to inhibitors, but they did indicate significant levels of PCR inhibition. When quantifying degraded samples, each kit provided different degradation indices (DI), with Investigator® Quantiplex® Pro indicating the largest DI and Quantifiler® Trio indicating the smallest DI. When the qPCR kits were paired with their respective STR kit to genotype highly degraded samples, the Investigator® 24plex QS and GlobalFiler® kits generated more complete profiles when the small target concentrations were used for calculating input amount.

  18. GHEP-ISFG collaborative simulated exercise for DVI/MPI: Lessons learned about large-scale profile database comparisons.

    PubMed

    Vullo, Carlos M; Romero, Magdalena; Catelli, Laura; Šakić, Mustafa; Saragoni, Victor G; Jimenez Pleguezuelos, María Jose; Romanini, Carola; Anjos Porto, Maria João; Puente Prieto, Jorge; Bofarull Castro, Alicia; Hernandez, Alexis; Farfán, María José; Prieto, Victoria; Alvarez, David; Penacino, Gustavo; Zabalza, Santiago; Hernández Bolaños, Alejandro; Miguel Manterola, Irati; Prieto, Lourdes; Parsons, Thomas

    2016-03-01

    The GHEP-ISFG Working Group has recognized the importance of assisting DNA laboratories to gain expertise in handling DVI or missing persons identification (MPI) projects which involve the need for large-scale genetic profile comparisons. Eleven laboratories participated in a DNA matching exercise to identify victims from a hypothetical conflict with 193 missing persons. The post mortem database was comprised of 87 skeletal remain profiles from a secondary mass grave displaying a minimal number of 58 individuals with evidence of commingling. The reference database was represented by 286 family reference profiles with diverse pedigrees. The goal of the exercise was to correctly discover re-associations and family matches. The results of direct matching for commingled remains re-associations were correct and fully concordant among all laboratories. However, the kinship analysis for missing persons identifications showed variable results among the participants. There was a group of laboratories with correct, concordant results but nearly half of the others showed discrepant results exhibiting likelihood ratio differences of several degrees of magnitude in some cases. Three main errors were detected: (a) some laboratories did not use the complete reference family genetic data to report the match with the remains, (b) the identity and/or non-identity hypotheses were sometimes wrongly expressed in the likelihood ratio calculations, and (c) many laboratories did not properly evaluate the prior odds for the event. The results suggest that large-scale profile comparisons for DVI or MPI is a challenge for forensic genetics laboratories and the statistical treatment of DNA matching and the Bayesian framework should be better standardized among laboratories. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Practical aspects of genetic identification of hallucinogenic and other poisonous mushrooms for clinical and forensic purposes

    PubMed Central

    Kowalczyk, Marek; Sekuła, Andrzej; Mleczko, Piotr; Olszowy, Zofia; Kujawa, Anna; Zubek, Szymon; Kupiec, Tomasz

    2015-01-01

    Aim To assess the usefulness of a DNA-based method for identifying mushroom species for application in forensic laboratory practice. Methods Two hundred twenty-one samples of clinical forensic material (dried mushrooms, food remains, stomach contents, feces, etc) were analyzed. ITS2 region of nuclear ribosomal DNA (nrDNA) was sequenced and the sequences were compared with reference sequences collected from the National Center for Biotechnology Information gene bank (GenBank). Sporological identification of mushrooms was also performed for 57 samples of clinical material. Results Of 221 samples, positive sequencing results were obtained for 152 (69%). The highest percentage of positive results was obtained for samples of dried mushrooms (96%) and food remains (91%). Comparison with GenBank sequences enabled identification of all samples at least at the genus level. Most samples (90%) were identified at the level of species or a group of closely related species. Sporological and molecular identification were consistent at the level of species or genus for 30% of analyzed samples. Conclusion Molecular analysis identified a larger number of species than sporological method. It proved to be suitable for analysis of evidential material (dried hallucinogenic mushrooms) in forensic genetic laboratories as well as to complement classical methods in the analysis of clinical material. PMID:25727040

  20. Practical aspects of genetic identification of hallucinogenic and other poisonous mushrooms for clinical and forensic purposes.

    PubMed

    Kowalczyk, Marek; Sekuła, Andrzej; Mleczko, Piotr; Olszowy, Zofia; Kujawa, Anna; Zubek, Szymon; Kupiec, Tomasz

    2015-02-01

    To assess the usefulness of a DNA-based method for identifying mushroom species for application in forensic laboratory practice. Two hundred twenty-one samples of clinical forensic material (dried mushrooms, food remains, stomach contents, feces, etc) were analyzed. ITS2 region of nuclear ribosomal DNA (nrDNA) was sequenced and the sequen-ces were compared with reference sequences collected from the National Center for Biotechnology Information gene bank (GenBank). Sporological identification of mushrooms was also performed for 57 samples of clinical material. Of 221 samples, positive sequencing results were obtained for 152 (69%). The highest percentage of positive results was obtained for samples of dried mushrooms (96%) and food remains (91%). Comparison with GenBank sequences enabled identification of all samples at least at the genus level. Most samples (90%) were identified at the level of species or a group of closely related species. Sporological and molecular identification were consistent at the level of species or genus for 30% of analyzed samples. Molecular analysis identified a larger number of species than sporological method. It proved to be suitable for analysis of evidential material (dried hallucinogenic mushrooms) in forensic genetic laboratories as well as to complement classical methods in the analysis of clinical material.

  1. Whole-Genome Sequencing in Microbial Forensic Analysis of Gamma-Irradiated Microbial Materials.

    PubMed

    Broomall, Stacey M; Ait Ichou, Mohamed; Krepps, Michael D; Johnsky, Lauren A; Karavis, Mark A; Hubbard, Kyle S; Insalaco, Joseph M; Betters, Janet L; Redmond, Brady W; Rivers, Bryan A; Liem, Alvin T; Hill, Jessica M; Fochler, Edward T; Roth, Pierce A; Rosenzweig, C Nicole; Skowronski, Evan W; Gibbons, Henry S

    2016-01-15

    Effective microbial forensic analysis of materials used in a potential biological attack requires robust methods of morphological and genetic characterization of the attack materials in order to enable the attribution of the materials to potential sources and to exclude other potential sources. The genetic homogeneity and potential intersample variability of many of the category A to C bioterrorism agents offer a particular challenge to the generation of attributive signatures, potentially requiring whole-genome or proteomic approaches to be utilized. Currently, irradiation of mail is standard practice at several government facilities judged to be at particularly high risk. Thus, initial forensic signatures would need to be recovered from inactivated (nonviable) material. In the study described in this report, we determined the effects of high-dose gamma irradiation on forensic markers of bacterial biothreat agent surrogate organisms with a particular emphasis on the suitability of genomic DNA (gDNA) recovered from such sources as a template for whole-genome analysis. While irradiation of spores and vegetative cells affected the retention of Gram and spore stains and sheared gDNA into small fragments, we found that irradiated material could be utilized to generate accurate whole-genome sequence data on the Illumina and Roche 454 sequencing platforms. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  2. Personal identification based on prescription eyewear.

    PubMed

    Berg, Gregory E; Collins, Randall S

    2007-03-01

    This study presents a web-based tool that can be used to assist in identification of unknown individuals using spectacle prescriptions. Currently, when lens prescriptions are used in forensic identifications, investigators are constrained to a simple "match" or "no-match" judgment with an antemortem prescription. It is not possible to evaluate the strength of the conclusion, or rather, the potential or real error rates associated with the conclusion. Three databases totaling over 385,000 individual prescriptions are utilized in this study to allow forensic analysts to easily determine the strength of individuation of a spectacle match to antemortem records by calculating the frequency at which the observed prescription occurs in various U.S. populations. Optical refractive errors are explained, potential states and combinations of refractive errors are described, measuring lens corrections is discussed, and a detailed description of the databases is presented. The practical application of this system is demonstrated using two recent forensic identifications. This research provides a valuable personal identification tool that can be used in cases where eyeglass portions are recovered in forensic contexts.

  3. Origin and development of forensic medicine in Egypt.

    PubMed

    Kharoshah, Magdy Abdel Azim; Zaki, Mamdouh Kamal; Galeb, Sherien Salah; Moulana, Ashraf Abdel Reheem; Elsebaay, Elsebaay Ahmed

    2011-01-01

    Egyptians are one of the first civilisations to practice the removal and examination of internal organs of humans. Their practices ranged from embalming to faith healing to surgery and autopsy. Modern radiological studies, together with various forensic techniques, allowed scientists unique glimpses of the state of health in Egypt 4000 years ago and discovered one of the earliest applications of autopsy, the main element of forensic medicine practice today. The Egyptian Forensic Medicine Authority handles a relatively large number of cases annually and depends on different assisting laboratories (forensic histopathology, microbiology, serology unit, DNA laboratory, forensic chemistry laboratory) as well as the Counterfeiting and Forgery unit. Crime scene investigations are performed mainly through the criminal laboratory related to the Ministry of Interior. Forensic Medicine is studied thoroughly in the faculty of medicine (undergraduates), as well as by forensic medical examiners at postgraduate level (diploma, master's and doctorate). This review recommends more scientific cooperation with universities in the field of forensic medicine and related sciences to solve various crimes with meticulous detail. Copyright © 2010 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  4. The reliability of forensic osteology--a case in point. Case study.

    PubMed

    Kemkes-Grottenthaler, A

    2001-03-01

    The medico-legal investigation of skeletons is a trans-disciplinary effort by forensic scientists as well as physical anthropologists. The advent of DNA extraction and amplification from bones and teeth has led to the assumption that morphological assessment of skeletal remains might soon become obsolete. But despite the introduction and success of molecular biology, the analysis of skeletal biology will remain an integral part of the identification process. This is due to the fact, that the skeletal record allows relatively fast and accurate inferences about the identity of the victim. Moreover, a standard biological profile may be established to effectively narrow the police investigator's search parameters. The following study demonstrates how skeletal biology may collaborate in the forensic investigation and support DNA fingerprinting evidence. In this case, the information gained from standard morphological methods about the unknown person's sex, age and heritage immediately led the police to suspect, that the remains were that of a young man from Vietnam, who had been missing for 2.5 years. The investigation then quickly shifted to prove the victim's identity via DNA extraction and mtDNA sequence analysis and biostatistical calculations involving questions of kinship [4].

  5. Error rates in forensic DNA analysis: definition, numbers, impact and communication.

    PubMed

    Kloosterman, Ate; Sjerps, Marjan; Quak, Astrid

    2014-09-01

    Forensic DNA casework is currently regarded as one of the most important types of forensic evidence, and important decisions in intelligence and justice are based on it. However, errors occasionally occur and may have very serious consequences. In other domains, error rates have been defined and published. The forensic domain is lagging behind concerning this transparency for various reasons. In this paper we provide definitions and observed frequencies for different types of errors at the Human Biological Traces Department of the Netherlands Forensic Institute (NFI) over the years 2008-2012. Furthermore, we assess their actual and potential impact and describe how the NFI deals with the communication of these numbers to the legal justice system. We conclude that the observed relative frequency of quality failures is comparable to studies from clinical laboratories and genetic testing centres. Furthermore, this frequency is constant over the five-year study period. The most common causes of failures related to the laboratory process were contamination and human error. Most human errors could be corrected, whereas gross contamination in crime samples often resulted in irreversible consequences. Hence this type of contamination is identified as the most significant source of error. Of the known contamination incidents, most were detected by the NFI quality control system before the report was issued to the authorities, and thus did not lead to flawed decisions like false convictions. However in a very limited number of cases crucial errors were detected after the report was issued, sometimes with severe consequences. Many of these errors were made in the post-analytical phase. The error rates reported in this paper are useful for quality improvement and benchmarking, and contribute to an open research culture that promotes public trust. However, they are irrelevant in the context of a particular case. Here case-specific probabilities of undetected errors are needed. These should be reported, separately from the match probability, when requested by the court or when there are internal or external indications for error. It should also be made clear that there are various other issues to consider, like DNA transfer. Forensic statistical models, in particular Bayesian networks, may be useful to take the various uncertainties into account and demonstrate their effects on the evidential value of the forensic DNA results. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  6. International Data on Radiological Sources

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Martha Finck; Margaret Goldberg

    2010-07-01

    ABSTRACT The mission of radiological dispersal device (RDD) nuclear forensics is to identify the provenance of nuclear and radiological materials used in RDDs and to aid law enforcement in tracking nuclear materials and routes. The application of databases to radiological forensics is to match RDD source material to a source model in the database, provide guidance regarding a possible second device, and aid the FBI by providing a short list of manufacturers and distributors, and ultimately to the last legal owner of the source. The Argonne/Idaho National Laboratory RDD attribution database is a powerful technical tool in radiological forensics. Themore » database (1267 unique vendors) includes all sealed sources and a device registered in the U.S., is complemented by data from the IAEA Catalogue, and is supported by rigorous in-lab characterization of selected sealed sources regarding physical form, radiochemical composition, and age-dating profiles. Close working relationships with global partners in the commercial sealed sources industry provide invaluable technical information and expertise in the development of signature profiles. These profiles are critical to the down-selection of potential candidates in either pre- or post- event RDD attribution. The down-selection process includes a match between an interdicted (or detonated) source and a model in the database linked to one or more manufacturers and distributors.« less

  7. Improvement and automation of a real-time PCR assay for vaginal fluids.

    PubMed

    De Vittori, E; Giampaoli, S; Barni, F; Baldi, M; Berti, A; Ripani, L; Romano Spica, V

    2016-05-01

    The identification of vaginal fluids is crucial in forensic science. Several molecular protocols based on PCR amplification of mfDNA (microflora DNA) specific for vaginal bacteria are now available. Unfortunately mfDNA extraction and PCR reactions require manual optimization of several steps. The aim of present study was the verification of a partial automatization of vaginal fluids identification through two instruments widely diffused in forensic laboratories: EZ1 Advanced robot and Rotor Gene Q 5Plex HRM. Moreover, taking advantage of 5-plex thermocycler technology, the ForFluid kit performances were improved by expanding the mfDNA characterization panel with a new bacterial target for vaginal fluids and with an internal positive control (IPC) to monitor PCR inhibition. Results underlined the feasibility of a semi-automated extraction of mfDNA using a BioRobot and demonstrated the analytical improvements of the kit. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  8. [Application and progress of RNA in forensic science].

    PubMed

    Gao, Lin-Lin; Li, You-Ying; Yan, Jiang-Wei; Liu, Ya-Cheng

    2011-12-01

    With the development of molecular biology, the evidences of genetics has been used widely in forensic sciences. DNA technology has played an important role in individual identification and paternity testing, RNA technology is showing more and more wide application in prospect. This article reviews the application and progress of RNA in forensic science including estimation of postmortem interval, bloodstain age, wound age, as well as determination of cause of death and the source of body fluids.

  9. DNA profiling of trace evidence--mitigating evidence in a dog biting case.

    PubMed

    Brauner, P; Reshef, A; Gorski, A

    2001-09-01

    A young girl was the victim of a severe dog attack. An animal, suspected of having caused the attack, was later impounded for investigation. Microclots of blood, recovered from the dog's fur, were analyzed by STR DNA. Results showed that this blood was not related to the biting. Other forensic evidence--hairs, fibers, and odontology--failed to connect a particular animal to the attack. The implications of these findings for the dog and its owners are discussed as well as other forensic methods for resolving such cases.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Allen, J; Velsko, S

    This report explores the question of whether meaningful conclusions can be drawn regarding the transmission relationship between two microbial samples on the basis of differences observed between the two sample's respective genomes. Unlike similar forensic applications using human DNA, the rapid rate of microbial genome evolution combined with the dynamics of infectious disease require a shift in thinking on what it means for two samples to 'match' in support of a forensic hypothesis. Previous outbreaks for SARS-CoV, FMDV and HIV were examined to investigate the question of how microbial sequence data can be used to draw inferences that link twomore » infected individuals by direct transmission. The results are counter intuitive with respect to human DNA forensic applications in that some genetic change rather than exact matching improve confidence in inferring direct transmission links, however, too much genetic change poses challenges, which can weaken confidence in inferred links. High rates of infection coupled with relatively weak selective pressure observed in the SARS-CoV and FMDV data lead to fairly low confidence for direct transmission links. Confidence values for forensic hypotheses increased when testing for the possibility that samples are separated by at most a few intermediate hosts. Moreover, the observed outbreak conditions support the potential to provide high confidence values for hypothesis that exclude direct transmission links. Transmission inferences are based on the total number of observed or inferred genetic changes separating two sequences rather than uniquely weighing the importance of any one genetic mismatch. Thus, inferences are surprisingly robust in the presence of sequencing errors provided the error rates are randomly distributed across all samples in the reference outbreak database and the novel sequence samples in question. When the number of observed nucleotide mutations are limited due to characteristics of the outbreak or the availability of only partial rather than whole genome sequencing, indel information was shown to have the potential to improve performance but only for select outbreak conditions. In examined HIV transmission cases, extended evolution proved to be the limiting factor in assigning high confidence to transmission links, however, the potential to correct for extended evolution not associated with transmission events is demonstrated. Outbreak specific conditions such as selective pressure (in the form of varying mutation rate), are shown to impact the strength of inference made and a Monte Carlo simulation tool is introduced, which is used to provide upper and lower bounds on the confidence values associated with a forensic hypothesis.« less

  11. Identification of a forensic case using microscopy and forensically informative nucleotide sequencing (FINS): a case study of small Indian civet (Viverricula indica).

    PubMed

    Sahajpal, Vivek; Goyal, S P

    2010-06-01

    The exhibits obtained in wildlife offence cases quite often present a challenging situation for the forensic expert. The selection of proper approach for analysis is vital for a successful analysis. A generalised forensic analysis approach should proceed from the use of non-destructive techniques (morphological and microscopic examination) to partially destructive and finally destructive techniques (DNA analysis). The findings of non-destructive techniques may sometime be inconclusive but they definitely help in steering further forensic analysis in a proper direction. We describe a recent case where a very small dried skin piece (<0.05 mg) with just one small trimmed guard hair (0.4 cm) on it was received for species identification. The single guard hair was examined microscopically to get an indication of the type of species. We also describe the extraction procedure with a lower amount of sample, using an automated extraction method (Qiagen Biorobot EZ1) and PCR amplification of three mitochondrial genes (16s rRNA, 12s rRNA and cytochrome b) for species identification. Microscopic examination of the single hair indicated a viverrid species but the initial DNA analysis with 16s rRNA (through NCBI BLAST) showed the highest homology (93%) with a hyaenid species (Hyaena hyaena). However, further DNA analysis based on 12s rRNA and cytochrome b gene proved that the species was indeed a viverrid i.e. Viverricula indica (small Indian civet). The highest homology shown with a Hyaenid species by the 16s rRNA sequence from the case sample was due to lack of a 16s rRNA sequence for Viverricula indica in the NCBI data base. The case highlights the importance of morphological and microscopic examinations in wildlife offence cases. With respect to DNA extraction technology we found that automatic extraction method of Biorobot EZ1 (Qiagen) is quite useful with less amount of sample (much below recommended amount). Copyright 2009 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

  12. Forensic identification in teeth with caries.

    PubMed

    Alia-García, Esther; Parra-Pecharromán, David; Sánchez-Díaz, Ana; Mendez, Susy; Royuela, Ana; Gil-Alberdi, Laura; López-Palafox, Juan; Del Campo, Rosa

    2015-12-01

    Human teeth are biological structures that resist extreme conditions thus becoming a useful source of DNA for human forensic identification purposes. When it is possible, forensic prefer only non-damaged teeth whereas those with cavities are usually rejected to avoid both external and internal bacterial contamination. Cavities are one of the most prevalent dental pathology and its incidence increases with ageing. The aim of this study was to validate the use of teeth with cavities for forensic identification. A total of 120 individual teeth from unrelated patients (60 healthy and 60 with cavities, respectively) extracted by a dentist as part of the normal process of treatment, were submitted for further analysis. Dental pulp was obtained after tooth fragmentation, complete DNA was extracted and the corresponding human identification profile was obtained by the AmpFlSTR® NGM SElect™ kit. Cariogenic microbiota was determined by PCR-DGGE with bacterial universal primers and bands were excised, re-amplified and sequenced. From the 120 dental pieces analyzed, a defined genetic profile was obtained in 81 (67.5%) of them, with no statistical differences between the healthy and the cavities-affected teeth. Statistical association between teeth status, DNA content and genetic profiles was not observed. Complex bacterial communities were only detected in the cavities group, being the Streptococcus/Enterococcus, and Lactobacillus genera the most represented. We conclude that teeth with cavities are as valid as healthy dental pieces for forensic human identification. Moreover, the severity of the cariogenic lesion as well as associated bacterial communities seems not to influence the establishment of human dental profiles. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  13. Genetic relationships between blowflies (Calliphoridae) of forensic importance.

    PubMed

    Stevens, J; Wall, R

    2001-08-15

    Phylogenetic relationships among blowfly (Calliphoridae) species of forensic importance are explored using DNA sequence data from the large sub-unit (lsu, 28S) ribosomal RNA (rRNA) gene, the study includes representatives of a range of calliphorid species commonly encountered in forensic analysis in Britain and Europe. The data presented provide a basis to define molecular markers, including the identification of highly informative intra-sequence regions, which may be of use in the identification of larvae for forensic entomology. Phylogenetic analysis of the sequences also provides new insights into the different evolutionary patterns apparent within the family Calliphoridae which, additionally, can provide a measure of the degree of genetic variation likely to be encountered within taxonomic groups of differing forensic utility.

  14. Mass spectrometry-based cDNA profiling as a potential tool for human body fluid identification.

    PubMed

    Donfack, Joseph; Wiley, Anissa

    2015-05-01

    Several mRNA markers have been exhaustively evaluated for the identification of human venous blood, saliva, and semen in forensic genetics. As new candidate human body fluid specific markers are discovered, evaluated, and reported in the scientific literature, there is an increasing trend toward determining the ideal markers for cDNA profiling of body fluids of forensic interest. However, it has not been determined which molecular genetics-based technique(s) should be utilized to assess the performance of these markers. In recent years, only a few confirmatory, mRNA/cDNA-based methods have been evaluated for applications in body fluid identification. The most frequently described methods tested to date include quantitative polymerase chain reaction (qPCR) and capillary electrophoresis (CE). However these methods, in particular qPCR, often favor narrow multiplex PCR due to the availability of a limited number of fluorescent dyes/tags. In an attempt to address this technological constraint, this study explored matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) for human body fluid identification via cDNA profiling of venous blood, saliva, and semen. Using cDNA samples at 20pg input phosphoglycerate kinase 1 (PGK1) amounts, body fluid specific markers for the candidate genes were amplified in their corresponding body fluid (i.e., venous blood, saliva, or semen) and absent in the remaining two (100% specificity). The results of this study provide an initial indication that MALDI-TOF MS is a potential fluorescent dye-free alternative method for body fluid identification in forensic casework. However, the inherent issues of low amounts of mRNA, and the damage caused to mRNA by environmental exposures, extraction processes, and storage conditions are important factors that significantly hinder the implementation of cDNA profiling into forensic casework. Published by Elsevier Ireland Ltd.

  15. The common occurrence of epistasis in the determination of human pigmentation and its impact on DNA-based pigmentation phenotype prediction.

    PubMed

    Pośpiech, Ewelina; Wojas-Pelc, Anna; Walsh, Susan; Liu, Fan; Maeda, Hitoshi; Ishikawa, Takaki; Skowron, Małgorzata; Kayser, Manfred; Branicki, Wojciech

    2014-07-01

    The role of epistatic effects in the determination of complex traits is often underlined but its significance in the prediction of pigmentation phenotypes has not been evaluated so far. The prediction of pigmentation from genetic data can be useful in forensic science to describe the physical appearance of an unknown offender, victim, or missing person who cannot be identified via conventional DNA profiling. Available forensic DNA prediction systems enable the reliable prediction of several eye and hair colour categories. However, there is still space for improvement. Here we verified the association of 38 candidate DNA polymorphisms from 13 genes and explored the extent to which interactions between them may be involved in human pigmentation and their impact on forensic DNA prediction in particular. The model-building set included 718 Polish samples and the model-verification set included 307 independent Polish samples and additional 72 samples from Japan. In total, 29 significant SNP-SNP interactions were found with 5 of them showing an effect on phenotype prediction. For predicting green eye colour, interactions between HERC2 rs12913832 and OCA2 rs1800407 as well as TYRP1 rs1408799 raised the prediction accuracy expressed by AUC from 0.667 to 0.697 and increased the prediction sensitivity by >3%. Interaction between MC1R 'R' variants and VDR rs731236 increased the sensitivity for light skin by >1% and by almost 3% for dark skin colour prediction. Interactions between VDR rs1544410 and TYR rs1042602 as well as between MC1R 'R' variants and HERC2 rs12913832 provided an increase in red/non-red hair prediction accuracy from an AUC of 0.902-0.930. Our results thus underline epistasis as a common phenomenon in human pigmentation genetics and demonstrate that considering SNP-SNP interactions in forensic DNA phenotyping has little impact on eye, hair and skin colour prediction. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Potential forensic biogeographic application of diatom colony consistency analysis employing pyrosequencing profiles of the 18S rDNA V7 region.

    PubMed

    Zhao, Yuancun; Chen, Xiaogang; Yang, Yiwen; Zhao, Xiaohong; Zhang, Shu; Gao, Zehua; Fang, Ting; Wang, Yufang; Zhang, Ji

    2018-05-07

    Diatom examination has always been used for the diagnosis of drowning in forensic practice. However, traditional examination of the microscopic features of diatom frustules is time-consuming and requires taxonomic expertise. In this study, we demonstrate a potential DNA-based method of inferring suspected drowning site using pyrosequencing (PSQ) of the V7 region of 18S ribosome DNA (18S rDNA) as a diatom DNA barcode. By employing a sparse representation-based AdvISER-M-PYRO algorithm, the original PSQ signals of diatom DNA mixtures were deciphered to determine the corresponding taxa of the composite diatoms. Additionally, we evaluated the possibility of correlating water samples to collection sites by analyzing the PSQ signal profiles of diatom mixtures contained in the water samples via multidimensional scaling. The results suggest that diatomaceous PSQ profile analysis could be used as a cost-effective method to deduce the geographical origin of an environmental bio-sample.

  17. Forensic identification of CITES protected slimming cactus (Hoodia) using DNA barcoding.

    PubMed

    Gathier, Gerard; van der Niet, Timotheus; Peelen, Tamara; van Vugt, Rogier R; Eurlings, Marcel C M; Gravendeel, Barbara

    2013-11-01

    Slimming cactus (Hoodia), found only in southwestern Africa, is a well-known herbal product for losing weight. Consequently, Hoodia extracts are sought-after worldwide despite a CITES Appendix II status. The failure to eradicate illegal trade is due to problems with detecting and identifying Hoodia using morphological and chemical characters. Our aim was to evaluate the potential of molecular identification of Hoodia based on DNA barcoding. Screening of nrITS1 and psbA-trnH DNA sequences from 26 accessions of Ceropegieae resulted in successful identification, while conventional chemical profiling using DLI-MS led to inaccurate detection and identification of Hoodia. The presence of Hoodia in herbal products was also successfully established using DNA sequences. A validation procedure of our DNA barcoding protocol demonstrated its robustness to changes in PCR conditions. We conclude that DNA barcoding is an effective tool for Hoodia detection and identification which can contribute to preventing illegal trade. © 2013 American Academy of Forensic Sciences.

  18. Automated extraction of DNA from blood and PCR setup using a Tecan Freedom EVO liquid handler for forensic genetic STR typing of reference samples.

    PubMed

    Stangegaard, Michael; Frøslev, Tobias G; Frank-Hansen, Rune; Hansen, Anders J; Morling, Niels

    2011-04-01

    We have implemented and validated automated protocols for DNA extraction and PCR setup using a Tecan Freedom EVO liquid handler mounted with the Te-MagS magnetic separation device (Tecan, Männedorf, Switzerland). The protocols were validated for accredited forensic genetic work according to ISO 17025 using the Qiagen MagAttract DNA Mini M48 kit (Qiagen GmbH, Hilden, Germany) from fresh whole blood and blood from deceased individuals. The workflow was simplified by returning the DNA extracts to the original tubes minimizing the risk of misplacing samples. The tubes that originally contained the samples were washed with MilliQ water before the return of the DNA extracts. The PCR was setup in 96-well microtiter plates. The methods were validated for the kits: AmpFℓSTR Identifiler, SGM Plus and Yfiler (Applied Biosystems, Foster City, CA), GenePrint FFFL and PowerPlex Y (Promega, Madison, WI). The automated protocols allowed for extraction and addition of PCR master mix of 96 samples within 3.5h. In conclusion, we demonstrated that (1) DNA extraction with magnetic beads and (2) PCR setup for accredited, forensic genetic short tandem repeat typing can be implemented on a simple automated liquid handler leading to the reduction of manual work, and increased quality and throughput. Copyright © 2011 Society for Laboratory Automation and Screening. Published by Elsevier Inc. All rights reserved.

  19. An accurate bacterial DNA quantification assay for HTS library preparation of human biological samples.

    PubMed

    Seashols-Williams, Sarah; Green, Raquel; Wohlfahrt, Denise; Brand, Angela; Tan-Torres, Antonio Limjuco; Nogales, Francy; Brooks, J Paul; Singh, Baneshwar

    2018-05-17

    Sequencing and classification of microbial taxa within forensically relevant biological fluids has the potential for applications in the forensic science and biomedical fields. The quantity of bacterial DNA from human samples is currently estimated based on quantity of total DNA isolated. This method can miscalculate bacterial DNA quantity due to the mixed nature of the sample, and consequently library preparation is often unreliable. We developed an assay that can accurately and specifically quantify bacterial DNA within a mixed sample for reliable 16S ribosomal DNA (16S rDNA) library preparation and high throughput sequencing (HTS). A qPCR method was optimized using universal 16S rDNA primers, and a commercially available bacterial community DNA standard was used to develop a precise standard curve. Following qPCR optimization, 16S rDNA libraries from saliva, vaginal and menstrual secretions, urine, and fecal matter were amplified and evaluated at various DNA concentrations; successful HTS data were generated with as low as 20 pg of bacterial DNA. Changes in bacterial DNA quantity did not impact observed relative abundances of major bacterial taxa, but relative abundance changes of minor taxa were observed. Accurate quantification of microbial DNA resulted in consistent, successful library preparations for HTS analysis. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Forensic genetic analyses in isolated populations with examples of central European Valachs and Roma.

    PubMed

    Ehler, Edvard; Vanek, Daniel

    2017-05-01

    Isolated populations present a constant threat to the correctness of forensic genetic casework. In this review article we present several examples of how analyzing samples from isolated populations can bias the results of the forensic statistics and analyses. We select our examples from isolated populations from central and southeastern Europe, namely the Valachs and the European Roma. We also provide the reader with general strategies and principles to improve the laboratory practice (best practice) and reporting of samples from supposedly isolated populations. These include reporting the precise population data used for computing the forensic statistics, using the appropriate θ correction factor for calculating allele frequencies, typing ancestry informative markers in samples of unknown or uncertain ethnicity and establishing ethnic-specific forensic databases. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  1. Microbial DNA fingerprinting of human fingerprints: dynamic colonization of fingertip microflora challenges human host inferences for forensic purposes

    PubMed Central

    Tims, Sebastian; van Wamel, Willem; Endtz, Hubert P.; Kayser, Manfred

    2009-01-01

    Human fingertip microflora is transferred to touched objects and may provide forensically relevant information on individual hosts, such as on geographic origins, if endogenous microbial skin species/strains would be retrievable from physical fingerprints and would carry geographically restricted DNA diversity. We tested the suitability of physical fingerprints for revealing human host information, with geographic inference as example, via microbial DNA fingerprinting. We showed that the transient exogenous fingertip microflora is frequently different from the resident endogenous bacteria of the same individuals. In only 54% of the experiments, the DNA analysis of the transient fingertip microflora allowed the detection of defined, but often not the major, elements of the resident microflora. Although we found microbial persistency in certain individuals, time-wise variation of transient and resident microflora within individuals was also observed when resampling fingerprints after 3 weeks. While microbial species differed considerably in their frequency spectrum between fingerprint samples from volunteers in Europe and southern Asia, there was no clear geographic distinction between Staphylococcus strains in a cluster analysis, although bacterial genotypes did not overlap between both continental regions. Our results, though limited in quantity, clearly demonstrate that the dynamic fingerprint microflora challenges human host inferences for forensic purposes including geographic ones. Overall, our results suggest that human fingerprint microflora is too dynamic to allow for forensic marker developments for retrieving human information. Electronic supplementary material The online version of this article (doi:10.1007/s00414-009-0352-9) contains supplementary material, which is available to authorized users. PMID:19551400

  2. Clinical and forensic signs related to opioids abuse.

    PubMed

    Dinis-Oliveira, Ricardo Jorge; Carvalho, Felix; Moreira, Roxana; Duarte, Jose Alberto; Proenca, Jorge Brandao; Santos, Agostinho; Magalhaes, Teresa

    2012-12-01

    For a good performance in Clinical and Forensic Toxicology it is important to be aware of the biological and non-biological signs and symptoms related to xenobiotic exposure. This manuscript highlights and analyzes clinical and forensic imaging related to opioids abuse critically. Particularly, respiratory depression, track marks and hemorrhages, skin "popping", practices of phlebotomy, tissue necrosis and ulceration, dermatitis, tongue hyperpigmentation, "coma blisters", intra-arterial administration, candidiasis, wounds associated with anthrax or clostridium contaminated heroin, desomorphine related lesions and characteristic non-biological evidences are some commonly reported findings in opioids abuse, which will be discussed. For this purpose, clinical and forensic cases from our database (National Institute of Legal Medicine and Forensic Sciences, North Branch, Portugal), in addition to literature data, are reviewed.

  3. Internal validation of the RapidHIT® ID system.

    PubMed

    Wiley, Rachel; Sage, Kelly; LaRue, Bobby; Budowle, Bruce

    2017-11-01

    Traditionally, forensic DNA analysis has required highly skilled forensic geneticists in a dedicated laboratory to generate short tandem repeat (STR) profiles. STR profiles are routinely used either to associate or exclude potential donors of forensic biological evidence. The typing of forensic reference samples has become more demanding, especially with the requirement in some jurisdictions to DNA profile arrestees. The Rapid DNA (RDNA) platform, the RapidHIT ® ID (IntegenX ® , Pleasanton, CA), is a fully automated system capable of processing reference samples in approximately 90min with minimal human intervention. Thus, the RapidHIT ID instrument can be deployed to non-laboratory environments (e.g., booking stations) and run by trained atypical personnel such as law enforcement. In order to implement the RapidHIT ID platform, validation studies are needed to define the performance and limitations of the system. Internal validation studies were undertaken with four early-production RapidHIT ID units. Reliable and concordant STR profiles were obtained from reference buccal swabs. Throughout the study, no contamination was observed. The overall first-pass success rate with an "expert-like system" was 72%, which is comparable to another current RDNA platform commercially available. The system's second-pass success rate (involving manual interpretation on first-pass inconclusive results) increased to 90%. Inhibitors (i.e., coffee, smoking tobacco, and chewing tobacco) did not appear to affect typing by the instrument system; however, substrate (i.e., swab type) did impact typing success. Additionally, one desirable feature not available with other Rapid systems is that in the event of a system failed run, a swab can be recovered and subsequently re-analyzed in a new sample cartridge. Therefore, rarely should additional sampling or swab consumption be necessary. The RapidHIT ID system is a robust and reliable tool capable of generating complete STR profiles within the forensic DNA typing laboratory or with proper training in decentralized environments by non-laboratory personnel. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Concordance of the ForenSeq™ system and characterisation of sequence-specific autosomal STR alleles across two major population groups.

    PubMed

    Devesse, Laurence; Ballard, David; Davenport, Lucinda; Riethorst, Immy; Mason-Buck, Gabriella; Syndercombe Court, Denise

    2018-05-01

    By using sequencing technology to genotype loci of forensic interest it is possible to simultaneously target autosomal, X and Y STRs as well as identity, ancestry and phenotypic informative SNPs, resulting in a breadth of data obtained from a single run that is considerable when compared to that generated with standard technologies. It is important however that this information aligns with the genotype data currently obtained using commercially available kits for CE-based investigations such that results are compatible with existing databases and hence can be of use to the forensic community. In this work, 400 samples were typed using commercially available STR kits and CE, as well as using the Ilumina ForenSeq™ DNA Signature Prep Kit and MiSeq ® FGx to assess concordance of autosomal STRs and population variability. Results show a concordance rate between the two technologies exceeding 99.98% while numerous novel sequence based alleles are described. In order to make use of the sequence variation observed, sequence specific allele frequencies were generated for White British and British Chinese populations. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Genetic polymorphisms, forensic efficiency and phylogenetic analysis of 15 autosomal STR loci in the Kazak population of Ili Kazak Autonomous Prefecture, northwestern China.

    PubMed

    Feng, Chunmei; Wang, Xin; Wang, Xiaolong; Yu, Hao; Zhang, Guohua

    2018-03-01

    We investigated the frequencies of 15 autosomal STR loci in the Kazak population of the Ili Kazak Autonomous Prefecture with the aim of expanding the available population information in human genetic databases and for forensic DNA analysis. Genetic polymorphisms of 15 autosomal short tandem repeat (STR) loci were analysed in 456 individuals of the Kazak population from Ili Kazakh Autonomous Prefecture, northwestern China. A total of 173 alleles at 15 autosomal STR loci were found; the allele frequencies ranged from 0.5022-0.0011. The combined power of discrimination and exclusion statistics for the 15 STR loci were 0.999 999 999 85 and 0.999 998 800 65, respectively. In addition, phylogenetic analysis involving the Ili Uygur population and other relevant populations was carried out. A neighbour-joining tree and multidimensional scaling plot were generated based on Nei's standard genetic distance. Results of the population comparison indicated that the Ili Uygur population was most closely related genetically to the Uygur populations from other regions in China. These findings are consistent with the historical and geographic backgrounds of these populations.

  6. Analysis of forensically used autosomal short tandem repeat markers in Polish and neighboring populations.

    PubMed

    Soltyszewski, Ireneusz; Plocienniczak, Andrzej; Fabricius, Hans Ake; Kornienko, Igor; Vodolazhsky, Dmitrij; Parson, Walther; Hradil, Roman; Schmitter, Hermann; Ivanov, Pavel; Kuzniar, Piotr; Malyarchuk, Boris A; Grzybowski, Tomasz; Woźniak, Marcin; Henke, Jurgen; Henke, Lotte; Olkhovets, Sergiv; Voitenko, Vladimir; Lagus, Vita; Ficek, Andrej; Minárik, Gabriel; de Knijff, Peter; Rebała, Krzysztof; Wysocka, Joanna; Kapińska, Ewa; Cybulska, Lidia; Mikulich, Alexei I; Tsybovsky, Iosif S; Szczerkowska, Zofia; Krajewski, Paweł; Ploski, Rafał

    2008-06-01

    The purpose of this study was to evaluate the homogeneity of Polish populations with respect to STRs chosen as core markers of the Polish Forensic National DNA Intelligence Database, and to provide reference allele frequencies and to explore the genetic interrelationship between Poland and neighboring countries. The allele frequency distribution of 10 STRs included in the SGMplus kit was analyzed among 2176 unrelated individuals from 6 regional Polish populations and among 4321 individuals from Germany (three samples), Austria, The Netherlands, Sweden, Czech Republic, Slovakia, Belarus, Ukraine and the Russian Federation (six samples). The statistical approach consisted of AMOVA, calculation of pairwise Rst values and analysis by multidimensional scaling. We found homogeneity of present day Poland and consistent differences between Polish and German populations which contrasted with relative similarities between Russian and German populations. These discrepancies between genetic and geographic distances were confirmed by analysis of an independent data set on Y chromosome STRs. Migrations of Goths, Viking influences, German settlements in the region of Volga river and/or forced population resettlements and other events related to World War II are the historic events which might have caused these finding.

  7. mtDNA Mutations and Their Role in Aging, Diseases and Forensic Sciences

    PubMed Central

    Zapico, Sara C.; Ubelaker, Douglas H.

    2013-01-01

    Mitochondria are independent organelles with their own DNA. As a primary function, mitochondria produce the energy for the cell through Oxidative Phosphorylation (OXPHOS) in the Electron Transport Chain (ETC). One of the toxic products of this process is Reactive Oxygen Species (ROS), which can induce oxidative damage in macromolecules like lipids, proteins and DNA. Mitochondrial DNA (mtDNA) is less protected and has fewer reparation mechanisms than nuclear DNA (nDNA), and as such is more exposed to oxidative, mutation-inducing damage. This review analyzes the causes and consequences of mtDNA mutations and their relationship with the aging process. Neurodegenerative diseases, related with the aging, are consequences of mtDNA mutations resulting in a decrease in mitochondrial function. Also described are “mitochondrial diseases”, pathologies produced by mtDNA mutations and whose symptoms are related with mitochondrial dysfunction. Finally, mtDNA haplogroups are defined in this review; these groups are important for determination of geographical origin of an individual. Additionally, different haplogroups exhibit variably longevity and risk of certain diseases. mtDNA mutations in aging and haplogroups are of special interest to forensic science research. Therefore this review will help to clarify the key role of mtDNA mutations in these processes and support further research in this area. PMID:24307969

  8. Reliability of Professional Judgments in Forensic Child Sexual Abuse Evaluations: Unsettled or Unsettling Science?

    ERIC Educational Resources Information Center

    Everson, Mark D.; Sandoval, Jose Miguel; Berson, Nancy; Crowson, Mary; Robinson, Harriet

    2012-01-01

    In the absence of photographic or DNA evidence, a credible eyewitness, or perpetrator confession, forensic evaluators in cases of alleged child sexual abuse must rely on psychosocial or "soft" evidence, often requiring substantial professional judgment for case determination. This article offers a three-part rebuttal to Herman's (2009) argument…

  9. Using Harry Potter to Introduce Students to DNA Fingerprinting & Forensic Science

    ERIC Educational Resources Information Center

    Palmer, Laura K.

    2010-01-01

    This lesson uses characters from the Harry Potter series of novels as a "hook" to stimulate students' interest in introductory forensic science. Students are guided through RFLP (restriction fragment length polymorphism) analysis using inexpensive materials and asked to interpret data from a mock crime scene. Importantly, the lesson provides an…

  10. Biochemistry and Molecular Biology Techniques for Person Characterization

    ERIC Educational Resources Information Center

    Herrero, Salvador; Ivorra, Jose Luis; Garcia-Sogo, Magdalena; Martinez-Cortina, Carmen

    2008-01-01

    Using the traditional serological tests and the most novel techniques for DNA fingerprinting, forensic scientists scan different traits that vary from person to person and use the data to include or exclude suspects based on matching with the evidence obtained in a criminal case. Although the forensic application of these methods is well known,…

  11. Paleomicrobiology: a Snapshot of Ancient Microbes and Approaches to Forensic Microbiology

    PubMed Central

    RIVERA-PEREZ, JESSICA I.; SANTIAGO-RODRIGUEZ, TASHA M.; TORANZOS, GARY A.

    2017-01-01

    Paleomicrobiology, or the study of ancient microorganisms, has raised both fascination and skepticism for many years. While paleomicrobiology is not a recent field, the application of emerging techniques, such as DNA sequencing, is proving essential and has provided novel information regarding the evolution of viruses, antibiotic resistance, saprophytes, and pathogens, as well as ancient health and disease status, cultural customs, ethnic diets, and historical events. In this review, we highlight the importance of studying ancient microbial DNA, its contributions to current knowledge, and the role that forensic paleomicrobiology has played in deciphering historical enigmas. We also discuss the emerging techniques used to study the microbial composition of ancient samples as well as major concerns that accompany ancient DNA analyses. PMID:27726770

  12. Evaluating the statistical power of DNA-based identification, exemplified by 'The missing grandchildren of Argentina'.

    PubMed

    Kling, Daniel; Egeland, Thore; Piñero, Mariana Herrera; Vigeland, Magnus Dehli

    2017-11-01

    Methods and implementations of DNA-based identification are well established in several forensic contexts. However, assessing the statistical power of these methods has been largely overlooked, except in the simplest cases. In this paper we outline general methods for such power evaluation, and apply them to a large set of family reunification cases, where the objective is to decide whether a person of interest (POI) is identical to the missing person (MP) in a family, based on the DNA profile of the POI and available family members. As such, this application closely resembles database searching and disaster victim identification (DVI). If parents or children of the MP are available, they will typically provide sufficient statistical evidence to settle the case. However, if one must resort to more distant relatives, it is not a priori obvious that a reliable conclusion is likely to be reached. In these cases power evaluation can be highly valuable, for instance in the recruitment of additional family members. To assess the power in an identification case, we advocate the combined use of two statistics: the Probability of Exclusion, and the Probability of Exceedance. The former is the probability that the genotypes of a random, unrelated person are incompatible with the available family data. If this is close to 1, it is likely that a conclusion will be achieved regarding general relatedness, but not necessarily the specific relationship. To evaluate the ability to recognize a true match, we use simulations to estimate exceedance probabilities, i.e. the probability that the likelihood ratio will exceed a given threshold, assuming that the POI is indeed the MP. All simulations are done conditionally on available family data. Such conditional simulations have a long history in medical linkage analysis, but to our knowledge this is the first systematic forensic genetics application. Also, for forensic markers mutations cannot be ignored and therefore current models and implementations must be extended. All the tools are freely available in Familias (http://www.familias.no) empowered by the R library paramlink. The above approach is applied to a large and important data set: 'The missing grandchildren of Argentina'. We evaluate the power of 196 families from the DNA reference databank (Banco Nacional de Datos Genéticos, http://www.bndg.gob.ar. As a result we show that 58 of the families have poor statistical power and require additional genetic data to enable a positive identification. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Repair of DNA damage caused by cytosine deamination in mitochondrial DNA of forensic case samples.

    PubMed

    Gorden, Erin M; Sturk-Andreaggi, Kimberly; Marshall, Charla

    2018-05-01

    DNA sequence damage from cytosine deamination is well documented in degraded samples, such as those from ancient and forensic contexts. This study examined the effect of a DNA repair treatment on mitochondrial DNA (mtDNA) from aged and degraded skeletal samples. DNA extracts from 21 non-probative, degraded skeletal samples (aged 50-70 years) were utilized for the analysis. A portion of each sample extract was subjected to DNA repair using a commercial repair kit, the New England BioLabs' NEBNext FFPE DNA Repair Kit (Ipswich, MA). MtDNA was enriched using PCR and targeted capture in a side-by-side experiment of untreated and repaired DNA. Sequencing was performed using both traditional (Sanger-type; STS) and next-generation sequencing (NGS) methods Although cytosine deamination was evident in the mtDNA sequence data, the observed level of damaged bases varied by sequencing method as well as by enrichment type. The STS PCR amplicon data did not show evidence of cytosine deamination that could be distinguished from background signal in either the untreated or repaired sample set. However, the same PCR amplicons showed 850 C → T/G → A substitutions consistent with cytosine deamination with variant frequencies (VFs) of up to 25% when sequenced using NGS methods The occurrence of base misincorporation due to cytosine deamination was reduced by 98% (to 10) in the NGS amplicon data after repair. The NGS capture data indicated low levels (1-2%) of cytosine deamination in mtDNA fragments that was effectively mitigated by DNA repair. The observed difference in the level of cytosine deamination between the PCR and capture enrichment methods can be attributed to the greater propensity for stochastic effects from the PCR enrichment technique employed (e.g., low template input, increased PCR cycles). Altogether these results indicate that DNA repair may be required when sequencing PCR-amplified DNA from degraded forensic case samples with NGS methods. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.

  14. Analysis of cellular and extracellular DNA in fingerprints

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Button, Julie M.

    It has been previously shown that DNA can be recovered from latent fingerprints left on various surfaces [R. A. H. van Oorschot and M. K. Jones, Nature 387, 767 (1997)]. However, the source of the DNA, extracellular versus cellular origin, is difficult to determine. If the DNA is cellular, it is believed to belong to skin cells while extracellular DNA is believed to originate from body fluids such as sweat [D. J. Daly et. al, Forensic Sci. Int. Genet. 6, 41-46 (2012); V. V. Vlassov et. al, BioEssays 29, 654-667 (2007)]. The origin of the DNA in fingerprints has implicationsmore » for processing and interpretation of forensic evidence. The determination of the origin of DNA in fingerprints is further complicated by the fact that the DNA in fingerprints tends to be at a very low quantity [R. A. H. van Oorschot and M. K. Jones, Nature 387, 767 (1997)]. This study examined fingerprints from five volunteers left on sterilized glass slides and plastic pens. Three fingerprints were left on each glass slide (thumb, index, and middle fingers) while the pens were held as if one was writing with them. The DNA was collected from the objects using the wet swabbing technique (TE buffer). Following collection, the cellular and extracellular components of each sample were separated using centrifugation and an acoustofluidics system. Centrifugation is still the primary separation technique utilized in forensics laboratories, while acoustic focusing uses sound waves to focus large particles (cells) into low pressure nodes, separating them from the rest of the sample matrix. After separation, all samples were quantified using real-time quantitative PCR (qPCR). The overall trend is that there is more DNA in the extracellular fractions than cellular fractions for both centrifugation and acoustofluidic processing. Additionally, more DNA was generally collected from the pen samples than the samples left on glass slides.« less

  15. A Critical Reassessment of the Role of Mitochondria in Tumorigenesis

    PubMed Central

    Salas, Antonio; Yao, Yong-Gang; Macaulay, Vincent; Vega, Ana; Carracedo, Ángel; Bandelt, Hans-Jürgen

    2005-01-01

    Background Mitochondrial DNA (mtDNA) is being analyzed by an increasing number of laboratories in order to investigate its potential role as an active marker of tumorigenesis in various types of cancer. Here we question the conclusions drawn in most of these investigations, especially those published in high-rank cancer research journals, under the evidence that a significant number of these medical mtDNA studies are based on obviously flawed sequencing results. Methods and Findings In our analyses, we take a phylogenetic approach and employ thorough database searches, which together have proven successful for detecting erroneous sequences in the fields of human population genetics and forensics. Apart from conceptual problems concerning the interpretation of mtDNA variation in tumorigenesis, in most cases, blocks of seemingly somatic mutations clearly point to contamination or sample mix-up and, therefore, have nothing to do with tumorigenesis. Conclusion The role of mitochondria in tumorigenesis remains unclarified. Our findings of laboratory errors in many contributions would represent only the tip of the iceberg since most published studies do not provide the raw sequence data for inspection, thus hindering a posteriori evaluation of the results. There is no precedent for such a concatenation of errors and misconceptions affecting a whole subfield of medical research. PMID:16187796

  16. TriXY-Homogeneous genetic sexing of highly degraded forensic samples including hair shafts.

    PubMed

    Madel, Maria-Bernadette; Niederstätter, Harald; Parson, Walther

    2016-11-01

    Sexing of biological evidence is an important aspect in forensic investigations. A routinely used molecular-genetic approach to this endeavour is the amelogenin sex test, which is integrated in most commercially available polymerase chain reaction (PCR) kits for human identification. However, this assay is not entirely effective in respect to highly degraded DNA samples. This study presents a homogeneous PCR assay for robust sex diagnosis, especially for the analysis of severely fragmented DNA. The introduced triplex for the X and Y chromosome (TriXY) is based on real-time PCR amplification of short intergenic sequences (<50bp) on both gonosomes. Subsequent PCR product examination and molecular-genetic sex-assignment rely on high-resolution melting (HRM) curve analysis. TriXY was optimized using commercially available multi-donor human DNA preparations of either male or female origin and successfully evaluated on challenging samples, including 46 ancient DNA specimens from archaeological excavations and a total of 16 DNA samples extracted from different segments of eight hair shafts of male and female donors. Additionally, sensitivity and cross-species amplification were examined to further test the assay's utility in forensic investigations. TriXY's closed-tube format avoids post-PCR sample manipulations and, therefore, distinctly reduces the risk of PCR product carry-over contamination and sample mix-up, while reducing labour and financial expenses at the same time. The method is sensitive down to the DNA content of approximately two diploid cells and has proven highly useful on severely fragmented and low quantity ancient DNA samples. Furthermore, it even allowed for sexing of proximal hair shafts with very good results. In summary, TriXY facilitates highly sensitive, rapid, and costeffective genetic sex-determination. It outperforms existing sexing methods both in terms of sensitivity and minimum required template molecule lengths. Therefore, we feel confident that TriXY will prove to be a reliable addition to the toolbox currently used for sex-typing in forensic genetics and other fields of research. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  17. The application of magnetic bead hybridization for the recovery and STR amplification of degraded and inhibited forensic DNA.

    PubMed

    Wang, Jing; McCord, Bruce

    2011-06-01

    A common problem in the analysis of forensic DNA evidence is the presence of environmentally degraded and inhibited DNA. Such samples produce a variety of interpretational problems such as allele imbalance, allele dropout and sequence specific inhibition. In an attempt to develop methods to enhance the recovery of this type of evidence, magnetic bead hybridization has been applied to extract and preconcentrate DNA sequences containing short tandem repeat (STR) alleles of interest. In this work, genomic DNA was fragmented by heating, and sequences associated with STR alleles were selectively hybridized to allele-specific biotinylated probes. Each particular biotinylated probe-DNA complex was bound to streptavidin-coated magnetic beads using enabling enrichment of target DNA sequences. Experiments conducted using degraded DNA samples, as well as samples containing a large concentration of inhibitory substances, showed good specificity and recovery of missing alleles. Based on the favorable results obtained with these specific probes, this method should prove useful as a tool to improve the recovery of alleles from degraded and inhibited DNA samples. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Genetic DNA profile in urine and hair follicles from patients who have undergone allogeneic hematopoietic stem cell transplantation.

    PubMed

    Santurtún, Ana; Riancho, José A; Santurtún, Maite; Richard, Carlos; Colorado, M Mercedes; García Unzueta, Mayte; Zarrabeitia, María T

    2017-09-01

    Biological samples from patients who have undergone allogeneic hematopoietic stem cell transplantation (HSCT) constitute a challenge for individual identification. In this study we analyzed the genetic profiles (by the amplification of 15 autosomic STRs) of HSCT patients found in different types of samples (blood, hair and urine) that may be the source of DNA in civil or criminal forensic cases. Our results show that while in hair follicles the donor component was not detected in any patient, thus being a reliable source of biological material for forensic identification, mixed chimerism was detected in urine samples from all patient, and no correlation was found between the time elapsed from the transplant and the percentage of chimerism. These results certainly have practical implications if the urine is being considered as a source of DNA for identification purposes in HSTC patients. Moreover, taking into consideration that chimerism was found not only in patients with leukocyturia (given the hematopoietic origin of leukocytes, this was expected), but also in those without observable leukocytes in the sediment, we conclude that an alternative source or sources of donor DNA must be implicated. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.

  19. Single cells for forensic DNA analysis--from evidence material to test tube.

    PubMed

    Brück, Simon; Evers, Heidrun; Heidorn, Frank; Müller, Ute; Kilper, Roland; Verhoff, Marcel A

    2011-01-01

    The purpose of this project was to develop a method that, while providing morphological quality control, allows single cells to be obtained from the surfaces of various evidence materials and be made available for DNA analysis in cases where only small amounts of cell material are present or where only mixed traces are found. With the SteREO Lumar.V12 stereomicroscope and UV unit from Zeiss, it was possible to detect and assess single epithelial cells on the surfaces of various objects (e.g., glass, plastic, metal). A digitally operated micromanipulator developed by aura optik was used to lift a single cell from the surface of evidence material and to transfer it to a conventional PCR tube or to an AmpliGrid(®) from Advalytix. The actual lifting of the cells was performed with microglobes that acted as carriers. The microglobes were held with microtweezers and were transferred to the DNA analysis receptacles along with the adhering cells. In a next step, the PCR can be carried out in this receptacle without removing the microglobe. Our method allows a single cell to be isolated directly from evidence material and be made available for forensic DNA analysis. © 2010 American Academy of Forensic Sciences.

  20. Molecular identification of python species: development and validation of a novel assay for forensic investigations.

    PubMed

    Ciavaglia, Sherryn A; Tobe, Shanan S; Donnellan, Stephen C; Henry, Julianne M; Linacre, Adrian M T

    2015-05-01

    Python snake species are often encountered in illegal activities and the question of species identity can be pertinent to such criminal investigations. Morphological identification of species of pythons can be confounded by many issues and molecular examination by DNA analysis can provide an alternative and objective means of identification. Our paper reports on the development and validation of a PCR primer pair that amplifies a segment of the mitochondrial cytochrome b gene that has been suggested previously as a good candidate locus for differentiating python species. We used this DNA region to perform species identification of pythons, even when the template DNA was of poor quality, as might be the case with forensic evidentiary items. Validation tests are presented to demonstrate the characteristics of the assay. Tests involved the cross-species amplification of this marker in non-target species, minimum amount of DNA template required, effects of degradation on product amplification and a blind trial to simulate a casework scenario that provided 100% correct identity. Our results demonstrate that this assay performs reliably and robustly on pythons and can be applied directly to forensic investigations where the presence of a species of python is in question. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  1. An "in Silico" DNA Cloning Experiment for the Biochemistry Laboratory

    ERIC Educational Resources Information Center

    Elkins, Kelly M.

    2011-01-01

    This laboratory exercise introduces students to concepts in recombinant DNA technology while accommodating a major semester project in protein purification, structure, and function in a biochemistry laboratory for junior- and senior-level undergraduate students. It is also suitable for forensic science courses focused in DNA biology and advanced…

  2. Checking of individuality by DNA profiling.

    PubMed

    Brdicka, R; Nürnberg, P

    1993-08-25

    A review of methods of DNA analysis used in forensic medicine for identification, paternity testing, etc. is provided. Among other techniques, DNA fingerprinting using different probes and polymerase chain reaction-based techniques such as amplified sequence polymorphisms and minisatellite variant repeat mapping are thoroughly described and both theoretical and practical aspects are discussed.

  3. The man behind the DNA fingerprints: an interview with Professor Sir Alec Jeffreys

    PubMed Central

    2013-01-01

    In this interview we talk with Professor Sir Alec Jeffreys about DNA fingerprinting, his wider scientific career, and the past, present and future of forensic DNA applications. The podcast with excerpts from this interview is available at: http://www.biomedcentral.com/biome/alec-jeffreys. PMID:24245655

  4. An evaluation of matching unknown writing inks with the United States International Ink Library.

    PubMed

    Laporte, Gerald M; Arredondo, Marlo D; McConnell, Tyra S; Stephens, Joseph C; Cantu, Antonio A; Shaffer, Douglas K

    2006-05-01

    Utilizing a database of standards for forensic casework is a valuable resource. Undoubtedly, as more standards (and corresponding information about the specimens) are collected, there is a greater certainty of identification when a questioned and a known item cannot be distinguished after a series of analyses. The United States Secret Service and the Internal Revenue Service National Forensic Laboratory jointly maintain the largest known forensic collection of writing inks in the world, which is comprised of over 8500 ink standards collected worldwide, dating back to the 1920s. This study was conducted to evaluate the reliability of matching arbitrarily purchased pens with known inks from a database. One hundred pens were randomly obtained from a variety of sources and their respective ink compositions were compared with standards. Eighty-five of the inks were determined to be suitable for comparison utilizing optical examinations and thin-layer chromatography. Three of the inks did not match any of the specimens on record; one of these inks was similar to an ink from an identical brand of pen that was in the database, but had a modified formulation.

  5. Pioneer identification of fake tiger claws using morphometric and DNA-based analysis in wildlife forensics in India.

    PubMed

    Vipin; Sharma, Vinita; Sharma, Chandra Prakash; Kumar, Ved Prakash; Goyal, Surendra Prakash

    2016-09-01

    The illegal trade in wildlife is a serious threat to the existence of wild animals throughout the world. The short supply and high demand for wildlife articles have caused an influx of many different forms of fake wildlife articles into this trade. The task of identifying the materials used in making such articles poses challenges in wildlife forensics as different approaches are required for species identification. Claws constitute 3.8% of the illegal animal parts (n=2899) received at the Wildlife Institute of India (WII) for species identification. We describe the identification of seized suspected tiger claws (n=18) using a combined approach of morphometric and DNA-based analysis. The differential keratin density, determined using X-ray radiographs, indicated that none of the 18 claws were of any large cat but were fake. We determined three claw measurements, viz. ac (from the external coronary dermo-epidermal interface to the epidermis of the skin fold connecting the palmar flanges of the coronary horn), bc (from the claw tip to the epidermis of the skin fold connecting the palmar flanges of the coronary horn) and the ratio bc/ac, for all the seized (n=18), tiger (n=23) and leopard (n=49) claws. Univariate and multivariate statistical analyses were performed using SPSS. A scatter plot generated using canonical discriminant function analysis revealed that of the 18 seized claws, 14 claws formed a cluster separate from the clusters of the tiger and leopard claws, whereas the remaining four claws were within the leopard cluster. Because a discrepancy was observed between the X-ray images and the measurements of these four claws, one of the claw that clustered with the leopard claws was chosen randomly and DNA analysis carried out using the cyt b (137bp) and 16S rRNA (410bp) genes. A BLAST search and comparison with the reference database at WII indicated that the keratin material of the claw was derived from Bos taurus (cattle). This is a pioneering discovery, and we suggest that a hierarchical combination of techniques be used for identifying claws involved in wildlife offences, i.e. that an X-ray, morphometric and DNA-based analysis be carried out, to ascertain whether the claws are of tigers or leopards. To identify species in the illegal wildlife trade morphometric and genetic reference database should be developed. Morphological features as well as DNA profiles need to be used for better implementation of the Wildlife (Protection) Act, 1972 of India and other laws/treaties in South-east Asia. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Refining the relevant population in forensic voice comparison - A response to Hicks et alii (2015) The importance of distinguishing information from evidence/observations when formulating propositions.

    PubMed

    Morrison, Geoffrey Stewart; Enzinger, Ewald; Zhang, Cuiling

    2016-12-01

    Hicks et alii [Sci. Just. 55 (2015) 520-525. http://dx.doi.org/10.1016/j.scijus.2015.06.008] propose that forensic speech scientists not use the accent of the speaker of questioned identity to refine the relevant population. This proposal is based on a lack of understanding of the realities of forensic voice comparison. If it were implemented, it would make data-based forensic voice comparison analysis within the likelihood ratio framework virtually impossible. We argue that it would also lead forensic speech scientists to present invalid unreliable strength of evidence statements, and not allow them to conduct the tests that would make them aware of this problem. Copyright © 2016 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

  7. Evaluation of reliability on STR typing at leukemic patients used for forensic purposes.

    PubMed

    Filoglu, G; Bulbul, O; Rayimoglu, G; Yediay, F E; Zorlu, T; Ongoren, S; Altuncul, H

    2014-06-01

    Over the past decades, main advances in the field of molecular biology, coupled with benefits in genomic technologies, have led to detailed molecular investigations in the genetic diversity generated by researchers. Short tandem repeat (STR) loci are polymorphic loci found throughout all eukaryotic genome. DNA profiling identification, parental testing and kinship analysis by analysis of STR loci have been widely used in forensic sciences since 1993. Malignant tissues may sometimes be the source of biological material for forensic analysis, including identification of individuals or paternity testing. There are a number of studies on microsatellite instability in different types of tumors by comparing the STR profiles of malignant and healthy tissues on the same individuals. Defects in DNA repair pathways (non-repair or mis-repair) and metabolism lead to an accumulation of microsatellite alterations in genomic DNA of various cancer types that result genomic instabilities on forensic analyses. Common forms of genomic instability are loss of heterozygosity (LOH) and microsatellite instability (MSI). In this study, the applicability of autosomal STR markers, which are routinely used in forensic analysis, were investigated in order to detect genotypes in blood samples collected from leukemic patients to estimate the reliability of the results when malignant tissues are used as a source of forensic individual identification. Specimens were collected from 90 acute and 10 chronic leukemia volunteers with oral swabs as well as their paired peripheral blood samples from the Oncology Centre of the Department of Hematology at Istanbul University, during the years 2010-2011. Specimens were tested and compared with 16 somatic STR loci (CSFIPO, THO1, TPOX, vWA, D2S1338, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D19S433, D21S11 and FGA) widely used in forensic identification and kinship. Only two STR instabilities were encountered among 100 specimens. An MSI in the FGA loci and a LOH in the D2S1338 loci were determined in two individuals separately. Our results demonstrate that the use of the biological samples from leukemia patients in forensic identification and kinship testing is questionable, especially if known microsatellite instability is available. Genetic instabilities may alter the STR polymorphism, leading to potential errors on forensic identification of individuals. Therefore, typing of autosomal STRs from leukemia patients should be performed with both healthy and malignant tissue samples of individual as references.

  8. Practical relevance of pattern uniqueness in forensic science.

    PubMed

    Jayaprakash, Paul T

    2013-09-10

    Uniqueness being unprovable, it has recently been argued that individualization in forensic science is irrelevant and, probability, as applied for DNA profiles, should be applied for all identifications. Critiques against uniqueness have omitted physical matching, a realistic and tangible individualization that supports uniqueness. Describing case examples illustrating pattern matches including physical matching, it is indicated that individualizations are practically relevant for forensic science as they establish facts on a definitive basis providing firm leads benefitting criminal investigation. As a tenet of forensic identification, uniqueness forms a fundamental paradigm relevant for individualization. Evidence on the indeterministic and stochastic causal pathways of characteristics in patterns available in the related fields of science sufficiently supports the proposition of uniqueness. Characteristics involved in physical matching and matching achieved in patterned evidence existing in the state of nature are not events amenable for counting; instead these are ensemble of visible units occupying the entire pattern area stretching the probability of re-occurrence of a verisimilitude pattern into infinity offering epistemic support to uniqueness. Observational methods are as respectable as instrumental or statistical methods since they are capable of generating results that are tangible and obviously valid as in physical matching. Applying the probabilistic interpretation used for DNA profiles to the other patterns would be unbefitting since these two are disparate, the causal pathways of the events, the loci, in the manipulated DNA profiles being determinable. While uniqueness enables individualizations, it does not vouch for eliminating errors. Instead of dismissing uniqueness and individualization, accepting errors as human or system failures and seeking remedial measures would benefit forensic science practice and criminal investigation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  9. Biological Evidence Management for DNA Analysis in Cases of Sexual Assault

    PubMed Central

    Magalhães, Teresa; Dinis-Oliveira, Ricardo Jorge; Silva, Benedita; Corte-Real, Francisco; Nuno Vieira, Duarte

    2015-01-01

    Biological evidence with forensic interest may be found in several cases of assault, being particularly relevant if sexually related. Sexual assault cases are characterized by low rates of disclosure, reporting, prosecution, and conviction. Biological evidence is sometimes the only way to prove the occurrence of sexual contact and to identify the perpetrator. The major focus of this review is to propose practical approaches and guidelines to help health, forensic, and law enforcement professionals to deal with biological evidence for DNA analysis. Attention should be devoted to avoiding contamination, degradation, and loss of biological evidence, as well as respecting specific measures to properly handle evidence (i.e., selection, collection, packing, sealing, labeling, storage, preservation, transport, and guarantee of the chain custody). Biological evidence must be carefully managed since the relevance of any finding in Forensic Genetics is determined, in the first instance, by the integrity and quantity of the samples submitted for analysis. PMID:26587562

  10. DNA-based identification of forensically important species of Sarcophagidae (Insecta: Diptera) from Rio de Janeiro, Brazil.

    PubMed

    Napoleão, K S; Mello-Patiu, C A; Oliveira-Costa, J; Takiya, D M; Silva, R; Moura-Neto, R S

    2016-05-06

    Sarcophagidae, or flesh flies, are of great importance in forensic entomology, but their effective application requires precise taxonomic identification, which relies almost exclusively on characteristics of the male genitalia. Given that female flies and larvae are most abundant in animal carcasses or on corpses, precise morphological identification can be difficult; therefore, DNA sequencing can be an additional tool for use in taxonomic identification. This paper analyzes part of the mitochondrial cytochrome c oxidase subunit I (COI) gene from three Sarcophagidae species of forensic importance in the City of Rio de Janeiro: Oxysarcodexia fluminensis, Peckia chrysostoma, and Peckia intermutans. COI fragments of 400 bp from 36 specimens of these three species were sequenced. No intraspecific differences were found among specimens of O. fluminensis, but P. chrysostoma and P. intermutans each had two haplotypes, ranging from 0 to 0.7%. The interspecific divergence was 8.5-11.6%, corroborating previously reported findings.

  11. Performance evaluation of a mitogenome capture and Illumina sequencing protocol using non-probative, case-type skeletal samples: Implications for the use of a positive control in a next-generation sequencing procedure.

    PubMed

    Marshall, Charla; Sturk-Andreaggi, Kimberly; Daniels-Higginbotham, Jennifer; Oliver, Robert Sean; Barritt-Ross, Suzanne; McMahon, Timothy P

    2017-11-01

    Next-generation ancient DNA technologies have the potential to assist in the analysis of degraded DNA extracted from forensic specimens. Mitochondrial genome (mitogenome) sequencing, specifically, may be of benefit to samples that fail to yield forensically relevant genetic information using conventional PCR-based techniques. This report summarizes the Armed Forces Medical Examiner System's Armed Forces DNA Identification Laboratory's (AFMES-AFDIL) performance evaluation of a Next-Generation Sequencing protocol for degraded and chemically treated past accounting samples. The procedure involves hybridization capture for targeted enrichment of mitochondrial DNA, massively parallel sequencing using Illumina chemistry, and an automated bioinformatic pipeline for forensic mtDNA profile generation. A total of 22 non-probative samples and associated controls were processed in the present study, spanning a range of DNA quantity and quality. Data were generated from over 100 DNA libraries by ten DNA analysts over the course of five months. The results show that the mitogenome sequencing procedure is reliable and robust, sensitive to low template (one ng control DNA) as well as degraded DNA, and specific to the analysis of the human mitogenome. Haplotypes were overall concordant between NGS replicates and with previously generated Sanger control region data. Due to the inherent risk for contamination when working with low-template, degraded DNA, a contamination assessment was performed. The consumables were shown to be void of human DNA contaminants and suitable for forensic use. Reagent blanks and negative controls were analyzed to determine the background signal of the procedure. This background signal was then used to set analytical and reporting thresholds, which were designated at 4.0X (limit of detection) and 10.0X (limit of quantiation) average coverage across the mitogenome, respectively. Nearly all human samples exceeded the reporting threshold, although coverage was reduced in chemically treated samples resulting in a ∼58% passing rate for these poor-quality samples. A concordance assessment demonstrated the reliability of the NGS data when compared to known Sanger profiles. One case sample was shown to be mixed with a co-processed sample and two reagent blanks indicated the presence of DNA above the analytical threshold. This contamination was attributed to sequencing crosstalk from simultaneously sequenced high-quality samples to include the positive control. Overall this study demonstrated that hybridization capture and Illumina sequencing provide a viable method for mitogenome sequencing of degraded and chemically treated skeletal DNA samples, yet may require alternative measures of quality control. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  12. [Training and research in forensic medicine: present situation and future challenges for medical schools in Chile].

    PubMed

    González, Leonardo; Inzunza, José Antonio; Bustos, Luis; Vallejos, Carlos; Gutiérrez, René

    2005-07-01

    Lawyers need some medical knowledge and physicians must know about forensics. To explore training and research programs in forensic medicine in Chilean universities. Deans of all Medicine Faculties in Chile were contacted by e-mail and invited to answer a questionnaire containing 21 questions. A survey of Chilean publications on forensic medicine was performed in Medline, Lilacs and SciELO databases. Fourteen deans answered the questionnaire. In all the responding faculties, forensic medicine is an obligatory course, generally during the fifth year and mostly combining theory with practice. In seven faculties, forensic medicine concepts are included in other courses. Forensics is taught in only two of 10 dental schools, two of 17 nursing schools, one of nine midwives schools and one of nine medical technology schools. It is not taught in phonoaudiology, kinesiology and nutrition schools. There are 74 physicians that teach the specialty but only 10 are certified by the National Board of Medical Specialty Certification (CONACEM). Treatment of most topics on forensics is insufficient. Thanatology is the strongest topic and forensic dentistry is the weakest. There are 52 publications in the area, mostly on "medical law". Forensic medicine is taught in medical schools mostly as thanatology. The knowledge of forensics among medical students is limited and must be improved.

  13. 'Mitominis': multiplex PCR analysis of reduced size amplicons for compound sequence analysis of the entire mtDNA control region in highly degraded samples.

    PubMed

    Eichmann, Cordula; Parson, Walther

    2008-09-01

    The traditional protocol for forensic mitochondrial DNA (mtDNA) analyses involves the amplification and sequencing of the two hypervariable segments HVS-I and HVS-II of the mtDNA control region. The primers usually span fragment sizes of 300-400 bp each region, which may result in weak or failed amplification in highly degraded samples. Here we introduce an improved and more stable approach using shortened amplicons in the fragment range between 144 and 237 bp. Ten such amplicons were required to produce overlapping fragments that cover the entire human mtDNA control region. These were co-amplified in two multiplex polymerase chain reactions and sequenced with the individual amplification primers. The primers were carefully selected to minimize binding on homoplasic and haplogroup-specific sites that would otherwise result in loss of amplification due to mis-priming. The multiplexes have successfully been applied to ancient and forensic samples such as bones and teeth that showed a high degree of degradation.

  14. DNA commission of the International Society of Forensic Genetics: Recommendations on the evaluation of STR typing results that may include drop-out and/or drop-in using probabilistic methods

    PubMed Central

    Gill, P.; Gusmão, L.; Haned, H.; Mayr, W.R.; Morling, N.; Parson, W.; Prieto, L.; Prinz, M.; Schneider, H.; Schneider, P.M.; Weir, B.S.

    2015-01-01

    DNA profiling of biological material from scenes of crimes is often complicated because the amount of DNA is limited and the quality of the DNA may be compromised. Furthermore, the sensitivity of STR typing kits has been continuously improved to detect low level DNA traces. This may lead to (1) partial DNA profiles and (2) detection of additional alleles. There are two key phenomena to consider: allelic or locus ‘drop-out’, i.e. ‘missing’ alleles at one or more genetic loci, while ‘drop-in’ may explain alleles in the DNA profile that are additional to the assumed main contributor(s). The drop-in phenomenon is restricted to 1 or 2 alleles per profile. If multiple alleles are observed at more than two loci then these are considered as alleles from an extra contributor and analysis can proceed as a mixture of two or more contributors. Here, we give recommendations on how to estimate probabilities considering drop-out, Pr(D), and drop-in, Pr(C). For reasons of clarity, we have deliberately restricted the current recommendations considering drop-out and/or drop-in at only one locus. Furthermore, we offer recommendations on how to use Pr(D) and Pr(C) with the likelihood ratio principles that are generally recommended by the International Society of Forensic Genetics (ISFG) as measure of the weight of the evidence in forensic genetics. Examples of calculations are included. An Excel spreadsheet is provided so that scientists and laboratories may explore the models and input their own data. PMID:22864188

  15. Development of a fast PCR protocol enabling rapid generation of AmpFℓSTR® Identifiler® profiles for genotyping of human DNA

    PubMed Central

    2012-01-01

    Background Traditional PCR methods for forensic STR genotyping require approximately 2.5 to 4 hours to complete, contributing a significant portion of the time required to process forensic DNA samples. The purpose of this study was to develop and validate a fast PCR protocol that enabled amplification of the 16 loci targeted by the AmpFℓSTR® Identifiler® primer set, allowing decreased cycling times. Methods Fast PCR conditions were achieved by substituting the traditional Taq polymerase for SpeedSTAR™ HS DNA polymerase which is designed for fast PCR, by upgrading to a thermal cycler with faster temperature ramping rates and by modifying cycling parameters (less time at each temperature) and adopting a two-step PCR approach. Results The total time required for the optimized protocol is 26 min. A total of 147 forensically relevant DNA samples were amplified using the fast PCR protocol for Identifiler. Heterozygote peak height ratios were not affected by fast PCR conditions, and full profiles were generated for single-source DNA amounts between 0.125 ng and 2.0 ng. Individual loci in profiles produced with the fast PCR protocol exhibited average n-4 stutter percentages ranging from 2.5 ± 0.9% (THO1) to 9.9 ± 2.7% (D2S1338). No increase in non-adenylation or other amplification artefacts was observed. Minor contributor alleles in two-person DNA mixtures were reliably discerned. Low level cross-reactivity (monomorphic peaks) was observed with some domestic animal DNA. Conclusions The fast PCR protocol presented offers a feasible alternative to current amplification methods and could aid in reducing the overall time in STR profile production or could be incorporated into a fast STR genotyping procedure for time-sensitive situations. PMID:22394458

  16. Development of a fast PCR protocol enabling rapid generation of AmpFℓSTR® Identifiler® profiles for genotyping of human DNA.

    PubMed

    Foster, Amanda; Laurin, Nancy

    2012-03-06

    Traditional PCR methods for forensic STR genotyping require approximately 2.5 to 4 hours to complete, contributing a significant portion of the time required to process forensic DNA samples. The purpose of this study was to develop and validate a fast PCR protocol that enabled amplification of the 16 loci targeted by the AmpFℓSTR® Identifiler® primer set, allowing decreased cycling times. Fast PCR conditions were achieved by substituting the traditional Taq polymerase for SpeedSTAR™ HS DNA polymerase which is designed for fast PCR, by upgrading to a thermal cycler with faster temperature ramping rates and by modifying cycling parameters (less time at each temperature) and adopting a two-step PCR approach. The total time required for the optimized protocol is 26 min. A total of 147 forensically relevant DNA samples were amplified using the fast PCR protocol for Identifiler. Heterozygote peak height ratios were not affected by fast PCR conditions, and full profiles were generated for single-source DNA amounts between 0.125 ng and 2.0 ng. Individual loci in profiles produced with the fast PCR protocol exhibited average n-4 stutter percentages ranging from 2.5 ± 0.9% (THO1) to 9.9 ± 2.7% (D2S1338). No increase in non-adenylation or other amplification artefacts was observed. Minor contributor alleles in two-person DNA mixtures were reliably discerned. Low level cross-reactivity (monomorphic peaks) was observed with some domestic animal DNA. The fast PCR protocol presented offers a feasible alternative to current amplification methods and could aid in reducing the overall time in STR profile production or could be incorporated into a fast STR genotyping procedure for time-sensitive situations.

  17. Evaluation of forensic genetic parameters of 12 STR loci in the Korean population using the InvestigatorⓇ HDplex kit.

    PubMed

    Jung, Ju Yeon; Kim, Eun Hye; Oh, Yu-Li; Park, Hyun-Chul; Hwang, Jung Ho; Lim, Si-Keun

    2017-09-01

    We genotyped and calculated the forensic parameters of 10 non-CODIS loci and 2 CODIS loci of 990 Korean individuals using the Investigator Ⓡ HDplex kit. No significant deviations from Hardy-Weinberg equilibrium (after Bonferroni correction for multiple testing) or genetic linkage disequilibrium were observed. The calculated matching probability and power of discrimination ranged from 0.0080 to 0.2014, and 0.7986 to 0.9920, respectively. We conclude that the markers of the kit are highly informative corroborative tools for forensic DNA analysis.

  18. An Alu-based, MGB Eclipse real-time PCR method for quantitation of human DNA in forensic samples.

    PubMed

    Nicklas, Janice A; Buel, Eric

    2005-09-01

    The forensic community needs quick, reliable methods to quantitate human DNA in crime scene samples to replace the laborious and imprecise slot blot method. A real-time PCR based method has the possibility of allowing development of a faster and more quantitative assay. Alu sequences are primate-specific and are found in many copies in the human genome, making these sequences an excellent target or marker for human DNA. This paper describes the development of a real-time Alu sequence-based assay using MGB Eclipse primers and probes. The advantages of this assay are simplicity, speed, less hands-on-time and automated quantitation, as well as a large dynamic range (128 ng/microL to 0.5 pg/microL).

  19. Evaluation of Forensic DNA Traces When Propositions of Interest Relate to Activities: Analysis and Discussion of Recurrent Concerns

    PubMed Central

    Biedermann, Alex; Champod, Christophe; Jackson, Graham; Gill, Peter; Taylor, Duncan; Butler, John; Morling, Niels; Hicks, Tacha; Vuille, Joelle; Taroni, Franco

    2016-01-01

    When forensic scientists evaluate and report on the probative strength of single DNA traces, they commonly rely on only one number, expressing the rarity of the DNA profile in the population of interest. This is so because the focus is on propositions regarding the source of the recovered trace material, such as “the person of interest is the source of the crime stain.” In particular, when the alternative proposition is “an unknown person is the source of the crime stain,” one is directed to think about the rarity of the profile. However, in the era of DNA profiling technology capable of producing results from small quantities of trace material (i.e., non-visible staining) that is subject to easy and ubiquitous modes of transfer, the issue of source is becoming less central, to the point that it is often not contested. There is now a shift from the question “whose DNA is this?” to the question “how did it get there?” As a consequence, recipients of expert information are now very much in need of assistance with the evaluation of the meaning and probative strength of DNA profiling results when the competing propositions of interest refer to different activities. This need is widely demonstrated in day-to-day forensic practice and is also voiced in specialized literature. Yet many forensic scientists remain reluctant to assess their results given propositions that relate to different activities. Some scientists consider evaluations beyond the issue of source as being overly speculative, because of the lack of relevant data and knowledge regarding phenomena and mechanisms of transfer, persistence and background of DNA. Similarly, encouragements to deal with these activity issues, expressed in a recently released European guideline on evaluative reporting (Willis et al., 2015), which highlights the need for rethinking current practice, are sometimes viewed skeptically or are not considered feasible. In this discussion paper, we select and discuss recurrent skeptical views brought to our attention, as well as some of the alternative solutions that have been suggested. We will argue that the way forward is to address now, rather than later, the challenges associated with the evaluation of DNA results (from small quantities of trace material) in light of different activities to prevent them being misrepresented in court. PMID:28018424

  20. Evaluation of Forensic DNA Traces When Propositions of Interest Relate to Activities: Analysis and Discussion of Recurrent Concerns.

    PubMed

    Biedermann, Alex; Champod, Christophe; Jackson, Graham; Gill, Peter; Taylor, Duncan; Butler, John; Morling, Niels; Hicks, Tacha; Vuille, Joelle; Taroni, Franco

    2016-01-01

    When forensic scientists evaluate and report on the probative strength of single DNA traces, they commonly rely on only one number, expressing the rarity of the DNA profile in the population of interest. This is so because the focus is on propositions regarding the source of the recovered trace material, such as "the person of interest is the source of the crime stain." In particular, when the alternative proposition is "an unknown person is the source of the crime stain," one is directed to think about the rarity of the profile. However, in the era of DNA profiling technology capable of producing results from small quantities of trace material (i.e., non-visible staining) that is subject to easy and ubiquitous modes of transfer, the issue of source is becoming less central, to the point that it is often not contested. There is now a shift from the question "whose DNA is this?" to the question "how did it get there?" As a consequence, recipients of expert information are now very much in need of assistance with the evaluation of the meaning and probative strength of DNA profiling results when the competing propositions of interest refer to different activities. This need is widely demonstrated in day-to-day forensic practice and is also voiced in specialized literature. Yet many forensic scientists remain reluctant to assess their results given propositions that relate to different activities. Some scientists consider evaluations beyond the issue of source as being overly speculative, because of the lack of relevant data and knowledge regarding phenomena and mechanisms of transfer, persistence and background of DNA. Similarly, encouragements to deal with these activity issues, expressed in a recently released European guideline on evaluative reporting (Willis et al., 2015), which highlights the need for rethinking current practice, are sometimes viewed skeptically or are not considered feasible. In this discussion paper, we select and discuss recurrent skeptical views brought to our attention, as well as some of the alternative solutions that have been suggested. We will argue that the way forward is to address now, rather than later, the challenges associated with the evaluation of DNA results (from small quantities of trace material) in light of different activities to prevent them being misrepresented in court.

  1. Forensic Analysis of Canine DNA Samples in the Undergraduate Biochemistry Laboratory

    ERIC Educational Resources Information Center

    Carson, Tobin M.; Bradley, Sharonda Q.; Fekete, Brenda L.; Millard, Julie T.; LaRiviere, Frederick J.

    2009-01-01

    Recent advances in canine genomics have allowed the development of highly distinguishing methods of analysis for both nuclear and mitochondrial DNA. We describe a laboratory exercise suitable for an undergraduate biochemistry course in which the polymerase chain reaction is used to amplify hypervariable regions of DNA from dog hair and saliva…

  2. Usefulness of telomere length in DNA from human teeth for age estimation.

    PubMed

    Márquez-Ruiz, Ana Belén; González-Herrera, Lucas; Valenzuela, Aurora

    2018-03-01

    Age estimation is widely used to identify individuals in forensic medicine. However, the accuracy of the most commonly used procedures is markedly reduced in adulthood, and these methods cannot be applied in practice when morphological information is limited. Molecular methods for age estimation have been extensively developed in the last few years. The fact that telomeres shorten at each round of cell division has led to the hypothesis that telomere length can be used as a tool to predict age. The present study thus aimed to assess the correlation between telomere length measured in dental DNA and age, and the effect of sex and tooth type on telomere length; a further aim was to propose a statistical regression model to estimate the biological age based on telomere length. DNA was extracted from 91 tooth samples belonging to 77 individuals of both sexes and 15 to 85 years old and was used to determine telomere length by quantitative real-time PCR. Our results suggested that telomere length was not affected by sex and was greater in molar teeth. We found a significant correlation between age and telomere length measured in DNA from teeth. However, the equation proposed to predict age was not accurate enough for forensic age estimation on its own. Age estimation based on telomere length in DNA from tooth samples may be useful as a complementary method which provides an approximate estimate of age, especially when human skeletal remains are the only forensic sample available.

  3. The persistence of human DNA in soil following surface decomposition.

    PubMed

    Emmons, Alexandra L; DeBruyn, Jennifer M; Mundorff, Amy Z; Cobaugh, Kelly L; Cabana, Graciela S

    2017-09-01

    Though recent decades have seen a marked increase in research concerning the impact of human decomposition on the grave soil environment, the fate of human DNA in grave soil has been relatively understudied. With the purpose of supplementing the growing body of literature in forensic soil taphonomy, this study assessed the relative persistence of human DNA in soil over the course of decomposition. Endpoint PCR was used to assess the presence or absence of human nuclear and mitochondrial DNA, while qPCR was used to evaluate the quantity of human DNA recovered from the soil beneath four cadavers at the University of Tennessee's Anthropology Research Facility (ARF). Human nuclear DNA from the soil was largely unrecoverable, while human mitochondrial DNA was detectable in the soil throughout all decomposition stages. Mitochondrial DNA copy abundances were not significantly different between decomposition stages and were not significantly correlated to soil edaphic parameters tested. There was, however, a significant positive correlation between mitochondrial DNA copy abundances and the human associated bacteria, Bacteroides, as estimated by 16S rRNA gene abundances. These results show that human mitochondrial DNA can persist in grave soil and be consistently detected throughout decomposition. Copyright © 2017 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.

  4. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nichols, T.

    The Nuclear Forensics Analysis Center (NFAC) is part of Savannah River National Laboratory (SRNL) and is one of only two USG National Laboratories accredited to perform nuclear forensic analyses to the requirements of ISO 17025. SRNL NFAC is capable of analyzing nuclear and radiological samples from bulk material to ultra-trace samples. NFAC provides analytical support to the FBI's Radiological Evidence Examination Facility (REEF), which is located within SRNL. REEF gives the FBI the capability to perform traditional forensics on material that is radiological and/or is contaminated. SRNL is engaged in research and development efforts to improve the USG technical nuclearmore » forensics capabilities. Research includes improving predictive signatures and developing a database containing comparative samples.« less

  5. Collecting sexual assault history and forensic evidence from adult women in the emergency department: a retrospective study.

    PubMed

    Tozzo, Pamela; Ponzano, Elena; Spigarolo, Gloria; Nespeca, Patrizia; Caenazzo, Luciana

    2018-05-29

    The objective of this retrospective study was to examine the discrepancy between information derived from written medical reports and the results of forensic DNA analyses on swabs collected from the victims in 122 cases of alleged sexual assault treated at the Emergency Department of Padua Hospital. The examination of discrepant results has proved useful to support a broader application of sexual assault management, particularly during the taking of case history. The Laboratory of Forensic Genetics of Padua University have processed samples from 122 sexual assault cases over a period of 5 years. Of the 103 cases in which the victim reported a penetration and ejaculation, only 67 (55% of all the samples) correlated with positive feedback match from the laboratory. In 36 cases in which the patient reported penetration with ejaculation, no male DNA was found in the samples collected. Therefore, there was a total of 41 cases in which the patient's report were not supported by laboratory data. In the remaining ten cases, which had an ambiguous history, 3 tested positively for the presence of male DNA. To avoid discrepancies between the medical reporting and reconstruction of sex crimes, it is crucial to deploy strategies which focus not only on the technical aspects of evidence collection, but also on how the victim's story is recorded; such efforts could lead to better management of sexual assault victims, and to a strengthened legal impact of forensic evidence and of crime reconstruction.

  6. A novel real time PCR assay using melt curve analysis for ivory identification.

    PubMed

    Kitpipit, Thitika; Penchart, Kitichaya; Ouithavon, Kanita; Satasook, Chutamas; Linacre, Adrian; Thanakiatkrai, Phuvadol

    2016-10-01

    Demand for ivory and expansion of human settlements have resulted in a rapid decline in the number of elephants. Enforcement of local and international laws and regulations requires identification of the species from which any ivory, or ivory products, originated. Further geographical assignment of the dead elephant from which the ivory was taken can assist in forensic investigations. In this study, a real-time PCR assay using melt curve analysis was developed and fully validated for forensic use. The presence or absence of three Elephantidae-specific and elephant species-specific melting peaks was used to identify the elephant species. Using 141 blood and ivory samples from the three extant elephant species, the assay demonstrated very high reproducibility and accuracy. The limit of detection was as low as 0.031ng of input DNA for conventional amplification and 0.002ng for nested amplification. Both DNA concentrations are typically encountered in forensic casework, especially for degraded samples. No cross-reactivity was observed for non-target species. Evaluation of direct amplification and nested amplification demonstrated the assay's flexibility and capability of analyzing low-template DNA samples and aged samples. Additionally, blind trial testing showed the assay's suitability application in real casework. In conclusion, wildlife forensic laboratories could use this novel, quick, and low-cost assay to help combat the continuing poaching crises leading to the collapse of elephant numbers in the wild. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  7. Molecular pathology and age estimation.

    PubMed

    Meissner, Christoph; Ritz-Timme, Stefanie

    2010-12-15

    Over the course of our lifetime a stochastic process leads to gradual alterations of biomolecules on the molecular level, a process that is called ageing. Important changes are observed on the DNA-level as well as on the protein level and are the cause and/or consequence of our 'molecular clock', influenced by genetic as well as environmental parameters. These alterations on the molecular level may aid in forensic medicine to estimate the age of a living person, a dead body or even skeletal remains for identification purposes. Four such important alterations have become the focus of molecular age estimation in the forensic community over the last two decades. The age-dependent accumulation of the 4977bp deletion of mitochondrial DNA and the attrition of telomeres along with ageing are two important processes at the DNA-level. Among a variety of protein alterations, the racemisation of aspartic acid and advanced glycation endproducs have already been tested for forensic applications. At the moment the racemisation of aspartic acid represents the pinnacle of molecular age estimation for three reasons: an excellent standardization of sampling and methods, an evaluation of different variables in many published studies and highest accuracy of results. The three other mentioned alterations often lack standardized procedures, published data are sparse and often have the character of pilot studies. Nevertheless it is important to evaluate molecular methods for their suitability in forensic age estimation, because supplementary methods will help to extend and refine accuracy and reliability of such estimates. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  8. Problems in Mitochondrial DNA forensics: while interpreting length heteroplasmy conundrum of various Sindhi and Baluchi ethnic groups of Pakistan.

    PubMed

    Bhatti, Shahzad; Aslam Khan, Muhammad; Abbas, Sana; Attimonelli, Marcella; Gonzalez, Gerardo Rodriguez; Aydin, Hikmet Hakan; de Souza, Erica Martinha Silva

    2018-05-01

    The insight heterodox genetics of mtDNA infer new perspectives at the level of human mitochondrial control region heteroplasmy, which is substantial in evolutionary as well as forensic interpretation. The main goal of this study is to interrogate the recurrence and resolve the ambiguity of blurry spectrum of heteroplasmy in the human mtDNA control region of 50 Baluchi and 116 Sindhi unrelated individuals. Sanger sequencing was employed classically, that was further investigated by minisequencing. Only 20% Baluchi and 25.8% Sindhi were homoplasmic, whereas rest of 80% Baluchi and 74.1% Sindhi exhibited at least one heteroplasmy within the specimen. In total, 166 individuals have length heteroplasmy (LH) found at positions 16189, 303-315, 568-573, and 514-524, whilst point mutation heteroplasmy (PMH) was detected at positions 73, 16093, 16189, and 16234, respectively. Overall LH was observed albeit high frequency in Sindhi ethnic group (82%) rather than Baluchi's (37%), whereas PMH accumulation was relatively extensive (24%) in Baluchi's than Sindhi's (11.2%). The obtained results ascertained that growing knowledge of heteroplasmy assisted to develop consciences in the forensic community that heteroplasmy plays a pivotal role in the legal interpretation on a regular basis and knowledge of its biological underpinnings has a vital niche in the forensic science. Limited studies have focused on heteroplasmy, yet scientific attention should be given, in order to determine its magnitude in different ethnic boundaries.

  9. Evaluation of the impact of genetic linkage in forensic identity and relationship testing for expanded DNA marker sets.

    PubMed

    Tillmar, Andreas O; Phillips, Chris

    2017-01-01

    Advances in massively parallel sequencing technology have enabled the combination of a much-expanded number of DNA markers (notably STRs and SNPs in one or combined multiplexes), with the aim of increasing the weight of evidence in forensic casework. However, when data from multiple loci on the same chromosome are used, genetic linkage can affect the final likelihood calculation. In order to study the effect of linkage for different sets of markers we developed the biostatistical tool ILIR, (Impact of Linkage on forensic markers for Identity and Relationship tests). The ILIR tool can be used to study the overall impact of genetic linkage for an arbitrary set of markers used in forensic testing. Application of ILIR can be useful during marker selection and design of new marker panels, as well as being highly relevant for existing marker sets as a way to properly evaluate the effects of linkage on a case-by-case basis. ILIR, implemented via the open source platform R, includes variation and genomic position reference data for over 40 STRs and 140 SNPs, combined with the ability to include additional forensic markers of interest. The use of the software is demonstrated with examples from several different established marker sets (such as the expanded CODIS core loci) including a review of the interpretation of linked genetic data. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. Probabilistic peak detection in CE-LIF for STR DNA typing.

    PubMed

    Woldegebriel, Michael; van Asten, Arian; Kloosterman, Ate; Vivó-Truyols, Gabriel

    2017-07-01

    In this work, we present a novel probabilistic peak detection algorithm based on a Bayesian framework for forensic DNA analysis. The proposed method aims at an exhaustive use of raw electropherogram data from a laser-induced fluorescence multi-CE system. As the raw data are informative up to a single data point, the conventional threshold-based approaches discard relevant forensic information early in the data analysis pipeline. Our proposed method assigns a posterior probability reflecting the data point's relevance with respect to peak detection criteria. Peaks of low intensity generated from a truly existing allele can thus constitute evidential value instead of fully discarding them and contemplating a potential allele drop-out. This way of working utilizes the information available within each individual data point and thus avoids making early (binary) decisions on the data analysis that can lead to error propagation. The proposed method was tested and compared to the application of a set threshold as is current practice in forensic STR DNA profiling. The new method was found to yield a significant improvement in the number of alleles identified, regardless of the peak heights and deviation from Gaussian shape. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Analysis of uni and bi-parental markers in mixture samples: Lessons from the 22nd GHEP-ISFG Intercomparison Exercise.

    PubMed

    Toscanini, U; Gusmão, L; Álava Narváez, M C; Álvarez, J C; Baldassarri, L; Barbaro, A; Berardi, G; Betancor Hernández, E; Camargo, M; Carreras-Carbonell, J; Castro, J; Costa, S C; Coufalova, P; Domínguez, V; Fagundes de Carvalho, E; Ferreira, S T G; Furfuro, S; García, O; Goios, A; González, R; de la Vega, A González; Gorostiza, A; Hernández, A; Jiménez Moreno, S; Lareu, M V; León Almagro, A; Marino, M; Martínez, G; Miozzo, M C; Modesti, N M; Onofri, V; Pagano, S; Pardo Arias, B; Pedrosa, S; Penacino, G A; Pontes, M L; Porto, M J; Puente-Prieto, J; Pérez, R Ramírez; Ribeiro, T; Rodríguez Cardozo, B; Rodríguez Lesmes, Y M; Sala, A; Santiago, B; Saragoni, V G; Serrano, A; Streitenberger, E R; Torres Morales, M A; Vannelli Rey, S A; Velázquez Miranda, M; Whittle, M R; Fernández, K; Salas, A

    2016-11-01

    Since 1992, the Spanish and Portuguese-Speaking Working Group of the ISFG (GHEP-ISFG) has been organizing annual Intercomparison Exercises (IEs) coordinated by the Quality Service at the National Institute of Toxicology and Forensic Sciences (INTCF) from Madrid, aiming to provide proficiency tests for forensic DNA laboratories. Each annual exercise comprises a Basic (recently accredited under ISO/IEC 17043: 2010) and an Advanced Level, both including a kinship and a forensic module. Here, we show the results for both autosomal and sex-chromosomal STRs, and for mitochondrial DNA (mtDNA) in two samples included in the forensic modules, namely a mixture 2:1 (v/v) saliva/blood (M4) and a mixture 4:1 (v/v) saliva/semen (M8) out of the five items provided in the 2014 GHEP-ISFG IE. Discrepancies, other than typos or nomenclature errors (over the total allele calls), represented 6.5% (M4) and 4.7% (M8) for autosomal STRs, 15.4% (M4) and 7.8% (M8) for X-STRs, and 1.2% (M4) and 0.0% (M8) for Y-STRs. Drop-out and drop-in alleles were the main cause of errors, with laboratories using different criteria regarding inclusion of minor peaks and stutter bands. Commonly used commercial kits yielded different results for a micro-variant detected at locus D12S391. In addition, the analysis of electropherograms revealed that the proportions of the contributors detected in the mixtures varied among the participants. In regards to mtDNA analysis, besides important discrepancies in reporting heteroplasmies, there was no agreement for the results of sample M4. Thus, while some laboratories documented a single control region haplotype, a few reported unexpected profiles (suggesting contamination problems). For M8, most laboratories detected only the haplotype corresponding to the saliva. Although the GHEP-ISFG has already a large experience in IEs, the present multi-centric study revealed challenges that still exist related to DNA mixtures interpretation. Overall, the results emphasize the need for further research and training actions in order to improve the analysis of mixtures among the forensic practitioners. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Species identification in forensic samples using the SPInDel approach: A GHEP-ISFG inter-laboratory collaborative exercise.

    PubMed

    Alves, Cíntia; Pereira, Rui; Prieto, Lourdes; Aler, Mercedes; Amaral, Cesar R L; Arévalo, Cristina; Berardi, Gabriela; Di Rocco, Florencia; Caputo, Mariela; Carmona, Cristian Hernandez; Catelli, Laura; Costa, Heloísa Afonso; Coufalova, Pavla; Furfuro, Sandra; García, Óscar; Gaviria, Anibal; Goios, Ana; Gómez, Juan José Builes; Hernández, Alexis; Hernández, Eva Del Carmen Betancor; Miranda, Luís; Parra, David; Pedrosa, Susana; Porto, Maria João Anjos; Rebelo, Maria de Lurdes; Spirito, Matteo; Torres, María Del Carmen Villalobos; Amorim, António; Pereira, Filipe

    2017-05-01

    DNA is a powerful tool available for forensic investigations requiring identification of species. However, it is necessary to develop and validate methods able to produce results in degraded and or low quality DNA samples with the high standards obligatory in forensic research. Here, we describe a voluntary collaborative exercise to test the recently developed Species Identification by Insertions/Deletions (SPInDel) method. The SPInDel kit allows the identification of species by the generation of numeric profiles combining the lengths of six mitochondrial ribosomal RNA (rRNA) gene regions amplified in a single reaction followed by capillary electrophoresis. The exercise was organized during 2014 by a Working Commission of the Spanish and Portuguese-Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG), created in 2013. The 24 participating laboratories from 10 countries were asked to identify the species in 11 DNA samples from previous GHEP-ISFG proficiency tests using a SPInDel primer mix and control samples of the 10 target species. A computer software was also provided to the participants to assist the analyses of the results. All samples were correctly identified by 22 of the 24 laboratories, including samples with low amounts of DNA (hair shafts) and mixtures of saliva and blood. Correct species identifications were obtained in 238 of the 241 (98.8%) reported SPInDel profiles. Two laboratories were responsible for the three cases of misclassifications. The SPInDel was efficient in the identification of species in mixtures considering that only a single laboratory failed to detect a mixture in one sample. This result suggests that SPInDel is a valid method for mixture analyses without the need for DNA sequencing, with the advantage of identifying more than one species in a single reaction. The low frequency of wrong (5.0%) and missing (2.1%) alleles did not interfere with the correct species identification, which demonstrated the advantage of using a method based on the analysis of multiple loci. Overall, the SPInDel method was easily implemented by laboratories using different genotyping platforms, the interpretation of results was straightforward and the SPInDel software was used without any problems. The results of this collaborative exercise indicate that the SPInDel method can be applied successfully in forensic casework investigations. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. DNA evidence: current perspective and future challenges in India.

    PubMed

    Verma, Sunil K; Goswami, Gajendra K

    2014-08-01

    Since the discovery of DNA fingerprinting technology in 1985 it has been used extensively as evidence in the court of law world-wide to establish the individual identity both in civil and criminal matters. In India, the first case of parentage dispute solved by the use of DNA fingerprinting technology was in 1989. Since then till date, the DNA technology has been used not only to resolve the cases of paternity and maternity disputes, but also for the establishment of individual identity in various criminal cases and for wildlife forensic identification. Since last half a decade, India is exercising to enact legislation on the use of DNA in the judicial realm and the draft 'Human DNA Bill-2012' is pending in the parliament. Largely, the promoters of forensic DNA testing have anticipated that DNA tests are nearly infallible and DNA technology could be the greatest single advance step in search for truth, conviction of the perpetrator, and acquittal of the innocent. The current article provides a comprehensive review on the status of DNA testing in India and elucidates the consequences of the admissibility of DNA as 'evidence' in the judicial dominion. In this backdrop of civil and criminal laws and changing ethical and societal attitudes, it is concluded that the DNA legislation in India and world-wide needs to be designed with utmost care. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Simultaneous detection of human mitochondrial DNA and nuclear-inserted mitochondrial-origin sequences (NumtS) using forensic mtDNA amplification strategies and pyrosequencing technology.

    PubMed

    Bintz, Brittania J; Dixon, Groves B; Wilson, Mark R

    2014-07-01

    Next-generation sequencing technologies enable the identification of minor mitochondrial DNA variants with higher sensitivity than Sanger methods, allowing for enhanced identification of minor variants. In this study, mixtures of human mtDNA control region amplicons were subjected to pyrosequencing to determine the detection threshold of the Roche GS Junior(®) instrument (Roche Applied Science, Indianapolis, IN). In addition to expected variants, a set of reproducible variants was consistently found in reads from one particular amplicon. A BLASTn search of the variant sequence revealed identity to a segment of a 611-bp nuclear insertion of the mitochondrial control region (NumtS) spanning the primer-binding sites of this amplicon (Nature 1995;378:489). Primers (Hum Genet 2012;131:757; Hum Biol 1996;68:847) flanking the insertion were used to confirm the presence or absence of the NumtS in buccal DNA extracts from twenty donors. These results further our understanding of human mtDNA variation and are expected to have a positive impact on the interpretation of mtDNA profiles using deep-sequencing methods in casework. © 2014 American Academy of Forensic Sciences.

  15. Sequence polymorphism data of the hypervariable regions of mitochondrial DNA in the Yadav population of Haryana.

    PubMed

    Verma, Kapil; Sharma, Sapna; Sharma, Arun; Dalal, Jyoti; Bhardwaj, Tapeshwar

    2018-06-01

    Genetic variations among humans occur both within and among populations and range from single nucleotide changes to multiple-nucleotide variants. These multiple-nucleotide variants are useful for studying the relationships among individuals or various population groups. The study of human genetic variations can help scientists understand how different population groups are biologically related to one another. Sequence analysis of hypervariable regions of human mitochondrial DNA (mtDNA) has been successfully used for the genetic characterization of different population groups for forensic purposes. It is well established that different ethnic or population groups differ significantly in their mtDNA distributions. In the last decade, very little research has been conducted on mtDNA variations in the Indian population, although such data would be useful for elucidating the history of human population expansion across the world. Moreover, forensic studies on mtDNA variations in the Indian subcontinent are also scarce, particularly in the northern part of India. In this report, variations in the hypervariable regions of mtDNA were analyzed in the Yadav population of Haryana. Different molecular diversity indices were computed. Further, the obtained haplotypes were classified into different haplogroups and the phylogenetic relationship between different haplogroups was inferred.

  16. Human genomic DNA quantitation system, H-Quant: development and validation for use in forensic casework.

    PubMed

    Shewale, Jaiprakash G; Schneida, Elaine; Wilson, Jonathan; Walker, Jerilyn A; Batzer, Mark A; Sinha, Sudhir K

    2007-03-01

    The human DNA quantification (H-Quant) system, developed for use in human identification, enables quantitation of human genomic DNA in biological samples. The assay is based on real-time amplification of AluYb8 insertions in hominoid primates. The relatively high copy number of subfamily-specific Alu repeats in the human genome enables quantification of very small amounts of human DNA. The oligonucleotide primers present in H-Quant are specific for human DNA and closely related great apes. During the real-time PCR, the SYBR Green I dye binds to the DNA that is synthesized by the human-specific AluYb8 oligonucleotide primers. The fluorescence of the bound SYBR Green I dye is measured at the end of each PCR cycle. The cycle at which the fluorescence crosses the chosen threshold correlates to the quantity of amplifiable DNA in that sample. The minimal sensitivity of the H-Quant system is 7.6 pg/microL of human DNA. The amplicon generated in the H-Quant assay is 216 bp, which is within the same range of the common amplifiable short tandem repeat (STR) amplicons. This size amplicon enables quantitation of amplifiable DNA as opposed to a quantitation of degraded or nonamplifiable DNA of smaller sizes. Development and validation studies were performed on the 7500 real-time PCR system following the Quality Assurance Standards for Forensic DNA Testing Laboratories.

  17. The Potential Use of Forensic DNA Methods Applied to Sand Fly Blood Meal Analysis to Identify the Infection Reservoirs of Anthroponotic Visceral Leishmaniasis.

    PubMed

    Inbar, Ehud; Lawyer, Philip; Sacks, David; Podini, Daniele

    2016-05-01

    In the Indian sub-continent, visceral leishmaniasis (VL), also known as kala azar, is a fatal form of leishmaniasis caused by the kinetoplastid parasite Leishmania donovani and transmitted by the sand fly Phlebotomus argentipes. VL is prevalent in northeast India where it is believed to have an exclusive anthroponotic transmission cycle. There are four distinct cohorts of L. donovani exposed individuals who can potentially serve as infection reservoirs: patients with active disease, cured VL cases, patients with post kala azar dermal leishmaniasis (PKDL), and asymptomatic individuals. The relative contribution of each group to sustaining the transmission cycle of VL is not known. To answer this critical epidemiological question, we have addressed the feasibility of an approach that would use forensic DNA methods to recover human DNA profiles from the blood meals of infected sand flies that would then be matched to reference DNA sampled from individuals living or working in the vicinity of the sand fly collections. We found that the ability to obtain readable human DNA fingerprints from sand flies depended entirely on the size of the blood meal and the kinetics of its digestion. Useable profiles were obtained from most flies within the first 24 hours post blood meal (PBM), with a sharp decline at 48 hours and no readable profiles at 72 hours. This early time frame necessitated development of a sensitive, nested-PCR method compatible with detecting L. donovani within a fresh, 24 hours blood meal in flies fed on infected hamsters. Our findings establish the feasibility of the forensic DNA method to directly trace the human source of an infected blood meal, with constraints imposed by the requirement that the flies be recovered for analysis within 24 hours of their infective feed.

  18. Biomek 3000: the workhorse in an automated accredited forensic genetic laboratory.

    PubMed

    Stangegaard, Michael; Meijer, Per-Johan; Børsting, Claus; Hansen, Anders J; Morling, Niels

    2012-10-01

    We have implemented and validated automated protocols for a wide range of processes such as sample preparation, PCR setup, and capillary electrophoresis setup using small, simple, and inexpensive automated liquid handlers. The flexibility and ease of programming enable the Biomek 3000 to be used in many parts of the laboratory process in a modern forensic genetics laboratory with low to medium sample throughput. In conclusion, we demonstrated that sample processing for accredited forensic genetic DNA typing can be implemented on small automated liquid handlers, leading to the reduction of manual work as well as increased quality and throughput.

  19. Triazolam blood concentrations in forensic cases in Canada.

    PubMed

    Joynt, B P

    1993-01-01

    Triazolam has been a controversial drug since its appearance on world markets as a hypnotic more than ten years ago. Whole blood concentrations of triazolam as found in forensic cases are cited in several categories; that is, impaired driving: 17 cases; sexual assault: four cases; death due to drugs: 45 cases; drug-related death (drugs contributed to the death but were not the ultimate cause): 20 cases; drug-involved death (drugs were present but were not felt to be a contributing factor): six cases; miscellaneous: one case. The data was gleaned from a forensic toxicology database designed and used by the Forensic Toxicology Sections of the Royal Canadian Mounted Police (RCMP) laboratories in Canada. Triazolam concentrations from selected references are included for comparison.

  20. The importance of distinguishing information from evidence/observations when formulating propositions.

    PubMed

    Hicks, T; Biedermann, A; de Koeijer, J A; Taroni, F; Champod, C; Evett, I W

    2015-12-01

    The value of forensic results crucially depends on the propositions and the information under which they are evaluated. For example, if a full single DNA profile for a contemporary marker system matching the profile of Mr A is assessed, given the propositions that the DNA came from Mr A and given it came from an unknown person, the strength of evidence can be overwhelming (e.g., in the order of a billion). In contrast, if we assess the same result given that the DNA came from Mr A and given it came from his twin brother (i.e., a person with the same DNA profile), the strength of evidence will be 1, and therefore neutral, unhelpful and irrelevant(1) to the case at hand. While this understanding is probably uncontroversial and obvious to most, if not all practitioners dealing with DNA evidence, the practical precept of not specifying an alternative source with the same characteristics as the one considered under the first proposition may be much less clear in other circumstances. During discussions with colleagues and trainees, cases have come to our attention where forensic scientists have difficulty with the formulation of propositions. It is particularly common to observe that results (e.g., observations) are included in the propositions, whereas-as argued throughout this note-they should not be. A typical example could be a case where a shoe-mark with a logo and the general pattern characteristics of a Nike Air Jordan shoe is found at the scene of a crime. A Nike Air Jordan shoe is then seized at Mr A's house and control prints of this shoe compared to the mark. The results (e.g., a trace with this general pattern and acquired characteristics corresponding to the sole of Mr A's shoe) are then evaluated given the propositions 'The mark was left by Mr A's Nike Air Jordan shoe-sole' and 'The mark was left by an unknown Nike Air Jordan shoe'. As a consequence, the footwear examiner will not evaluate part of the observations (i.e., the mark presents the general pattern of a Nike Air Jordan) whereas they can be highly informative. Such examples can be found in all forensic disciplines. In this article, we present a few such examples and discuss aspects that will help forensic scientists with the formulation of propositions. In particular, we emphasise on the usefulness of notation to distinguish results that forensic scientists should evaluate from case information that the Court will evaluate. Copyright © 2015 The Chartered Society of Forensic Sciences. Published by Elsevier Ireland Ltd. All rights reserved.

  1. Repatriation and Identification of Finnish World War II Soldiers

    PubMed Central

    Palo, Jukka U.; Hedman, Minttu; Söderholm, Niklas; Sajantila, Antti

    2007-01-01

    Aim To present a summary of the organization, field search, repatriation, forensic anthropological examination, and DNA analysis for the purpose of identification of Finnish soldiers with unresolved fate in World War II. Methods Field searches were organized, executed, and financed by the Ministry of Education and the Association for Cherishing the Memory of the Dead of the War. Anthropological examination conducted on human remains retrieved in the field searches was used to establish the minimum number of individuals and description of the skeletal diseases, treatment, anomalies, or injuries. DNA tests were performed by extracting DNA from powdered bones and blood samples from relatives. Mitochondrial DNA (mtDNA) sequence comparisons, together with circumstantial evidence, were used to connect the remains to the putative family members. Results At present, the skeletal remains of about a thousand soldiers have been found and repatriated. In forensic anthropological examination, several injuries related to death were documented. For the total of 181 bone samples, mtDNA HVR-1 and HVR-2 sequences were successfully obtained for 167 (92.3%) and 148 (81.8%) of the samples, respectively. Five samples yielded no reliable sequence data. Our data suggests that mtDNA preserves at least for 60 years in the boreal acidic soil. The quality of the obtained mtDNA sequence data varied depending on the sample bone type, with long compact bones (femur, tibia and humerus) having significantly better (90.0%) success rate than other bones (51.2%). Conclusion Although more than 60 years have passed since the World War II, our experience is that resolving the fate of soldiers missing in action is still of uttermost importance for people having lost their relatives in the war. Although cultural and individual differences may exist, our experience presented here gives a good perspective on the importance of individual identification performed by forensic professionals. PMID:17696308

  2. New Forensics Methods Looking More Like CSI: Rapid DNA Analysis, Proteomics, and New Technology Increasingly Impact Forensics Investigations.

    PubMed

    Mertz, Leslie

    2017-01-01

    If CSI and those other police procedural TV shows are to be believed, criminals don't have a chance. A finger smudge on a light switch, a flake of skin, or a sweat-stained fiber is all the information an investigator needs to positively identify the perpetrator and put him or her behind bars.

  3. Isolation and characterization of DNA from archaeological bone.

    PubMed

    Hagelberg, E; Clegg, J B

    1991-04-22

    DNA was extracted from human and animal bones recovered from archaeological sites and mitochondrial DNA sequences were amplified from the extracts using the polymerase chain reaction. Evidence is presented that the amplified sequences are authentic and do not represent contamination by extraneous DNA. The results show that significant amounts of genetic information can survive for long periods in bone, and have important implications for evolutionary genetics, anthropology and forensic science.

  4. Genetic investigation of 100 heart genes in sudden unexplained death victims in a forensic setting

    PubMed Central

    Christiansen, Sofie Lindgren; Hertz, Christin Løth; Ferrero-Miliani, Laura; Dahl, Morten; Weeke, Peter Ejvin; LuCamp; Ottesen, Gyda Lolk; Frank-Hansen, Rune; Bundgaard, Henning; Morling, Niels

    2016-01-01

    In forensic medicine, one-third of the sudden deaths remain unexplained after medico-legal autopsy. A major proportion of these sudden unexplained deaths (SUD) are considered to be caused by inherited cardiac diseases. Sudden cardiac death (SCD) may be the first manifestation of these diseases. The purpose of this study was to explore the yield of next-generation sequencing of genes associated with SCD in a cohort of SUD victims. We investigated 100 genes associated with cardiac diseases in 61 young (1–50 years) SUD cases. DNA was captured with the Haloplex target enrichment system and sequenced using an Illumina MiSeq. The identified genetic variants were evaluated and classified as likely, unknown or unlikely to have a functional effect. The criteria for this classification were based on the literature, databases, conservation and prediction of the effect of the variant. We found that 21 (34%) individuals carried variants with a likely functional effect. Ten (40%) of these variants were located in genes associated with cardiomyopathies and 15 (60%) of the variants in genes associated with cardiac channelopathies. Nineteen individuals carried variants with unknown functional effect. Our findings indicate that broad genetic investigation of SUD victims increases the diagnostic outcome, and the investigation should comprise genes involved in both cardiomyopathies and cardiac channelopathies. PMID:27650965

  5. Genetic investigation of 100 heart genes in sudden unexplained death victims in a forensic setting.

    PubMed

    Christiansen, Sofie Lindgren; Hertz, Christin Løth; Ferrero-Miliani, Laura; Dahl, Morten; Weeke, Peter Ejvin; LuCamp; Ottesen, Gyda Lolk; Frank-Hansen, Rune; Bundgaard, Henning; Morling, Niels

    2016-12-01

    In forensic medicine, one-third of the sudden deaths remain unexplained after medico-legal autopsy. A major proportion of these sudden unexplained deaths (SUD) are considered to be caused by inherited cardiac diseases. Sudden cardiac death (SCD) may be the first manifestation of these diseases. The purpose of this study was to explore the yield of next-generation sequencing of genes associated with SCD in a cohort of SUD victims. We investigated 100 genes associated with cardiac diseases in 61 young (1-50 years) SUD cases. DNA was captured with the Haloplex target enrichment system and sequenced using an Illumina MiSeq. The identified genetic variants were evaluated and classified as likely, unknown or unlikely to have a functional effect. The criteria for this classification were based on the literature, databases, conservation and prediction of the effect of the variant. We found that 21 (34%) individuals carried variants with a likely functional effect. Ten (40%) of these variants were located in genes associated with cardiomyopathies and 15 (60%) of the variants in genes associated with cardiac channelopathies. Nineteen individuals carried variants with unknown functional effect. Our findings indicate that broad genetic investigation of SUD victims increases the diagnostic outcome, and the investigation should comprise genes involved in both cardiomyopathies and cardiac channelopathies.

  6. Allele frequency data for 15 autosomal STR loci in eight Indonesian subpopulations.

    PubMed

    Venables, Samantha J; Daniel, Runa; Sarre, Stephen D; Soedarsono, Nurtami; Sudoyo, Herawati; Suryadi, Helena; van Oorschot, Roland A H; Walsh, Simon J; Widodo, Putut T; McNevin, Dennis

    2016-01-01

    Evolutionary and cultural history can affect the genetic characteristics of a population and influences the frequency of different variants at a particular genetic marker (allele frequency). These characteristics directly influence the strength of forensic DNA evidence and make the availability of suitable allele frequency information for every discrete country or jurisdiction highly relevant. Population sub-structure within Indonesia has not been well characterised but should be expected given the complex geographical, linguistic and cultural architecture of the Indonesian population. Here we use forensic short tandem repeat (STR) markers to identify a number of distinct genetic subpopulations within Indonesia and calculate appropriate population sub-structure correction factors. This data represents the most comprehensive investigation of population sub-structure within Indonesia to date using these markers. The results demonstrate that significant sub-structure is present within the Indonesian population and must be accounted for using island specific allele frequencies and corresponding sub-structure correction factors in the calculation of forensic DNA match statistics. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Forensic interlaboratory evaluation of the ForFLUID kit for vaginal fluids identification.

    PubMed

    Giampaoli, Saverio; Alessandrini, Federica; Berti, Andrea; Ripani, Luigi; Choi, Ajin; Crab, Roselien; De Vittori, Elisabetta; Egyed, Balazs; Haas, Cordula; Lee, Hwan Young; Korabecná, Marie; Noel, Fabrice; Podini, Daniele; Tagliabracci, Adriano; Valentini, Alessio; Romano Spica, Vincenzo

    2014-01-01

    Identification of vaginal fluids is an important step in the process of sexual assaults confirmation. Advances in both microbiology and molecular biology defined technical approaches allowing the discrimination of body fluids. These protocols are based on the identification of specific bacterial communities by microfloraDNA (mfDNA) amplification. A multiplex real time-PCR assay (ForFLUID kit) has been developed for identifying biological fluids and for discrimination among vaginal, oral and fecal samples. In order to test its efficacy and reliability of the assay in the identification of vaginal fluids, an interlaboratory evaluation has been performed on homogeneous vaginal swabs. All the involved laboratories were able to correctly recognize all the vaginal swabs, and no false positives were identified when the assay was applied on non-vaginal samples. The assay represents an useful molecular tool that can be easily adopted by forensic geneticists involved in vaginal fluid identification. Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  8. Case report: on the use of the HID-Ion AmpliSeq™ Ancestry Panel in a real forensic case.

    PubMed

    Hollard, C; Keyser, C; Delabarde, T; Gonzalez, A; Vilela Lamego, C; Zvénigorosky, V; Ludes, B

    2017-03-01

    In the absence of any other conclusive forensic evidence, DNA profiling is the method of choice for body identification. This study focuses on the case of a carbonized corpse whose complete autosomal short tandem repeat (STR) profile could not lead to direct identification by the investigators. To assist in the progress of investigation, we endeavoured to determine the biogeographical origin and eye colour of the deceased individual. Along with Y chromosome and mitochondrial DNA analyses, we applied a next-generation sequencing (NGS) approach to the study of ancestry informative markers (AIMs) using the HID-Ion AmpliSeq™ Ancestry Panel launched by Thermo Fisher Scientific. This work gave us the opportunity to test this new technology in a real forensic case. Although this study highlights the benefits of such a combined approach, as it markedly improves the specificity of the biogeographical profile, it also underlines the need for the accurate characterization of a larger collection of reference populations and the necessity of caution in data interpretation.

  9. DNA survival and physical and histological properties of heat-induced alterations in burnt bones.

    PubMed

    Imaizumi, K; Taniguchi, K; Ogawa, Y

    2014-05-01

    During forensic casework, it is vital to be able to obtain valuable information from burnt bone fragments to ascertain the identity of the victim. Here, we report the findings of an experimental study on burnt bovine compact bone segments. Compact bones were cut to size and heated in an electric furnace at a temperature range of 100–1,100 °C with 100 °C increments. Heat-induced alterations to the bone color,weight, volume, and density were monitored using gross morphology and micro-focus X-ray computed tomography.We found that the increase in temperature caused the color of the compact bones to change in order of yellow, brown, gray,and white. In contrast to the weight reduction that occurred immediately after burning, we measured no significant reduction in volume even at 600 °C; however, volume reduced drastically once the temperature reached 700 °C. Light microscopic histological observations of burnt bone revealed heat induced alterations such as cracking and separation of the osteons at higher temperatures. In addition to these findings,we sought to examine the survival of DNA in the burnt bones using polymerase chain reaction of mitochondrial DNA. No amplification was found in the specimens burnt at 250 °C or higher, indicating the likely difficulty in testing the DNA of burnt bones from forensic casework. The results of this study will enable an estimation of the burning temperatures of burnt bones found in forensic cases and will provide an important framework with which to interpret data obtained during anthropological testing and DNA typing.

  10. Applicability of the ParaDNA(®) Screening System to Seminal Samples.

    PubMed

    Tribble, Nicholas D; Miller, Jamie A D; Dawnay, Nick; Duxbury, Nicola J

    2015-05-01

    Seminal fluid represents a common biological material recovered from sexual assault crime scenes. Such samples can be prescreened using different techniques to determine cell type and relative amount before submitting for full STR profiling. The ParaDNA(®) Screening System is a novel forensic test which identifies the presence of DNA through amplification and detection of two common STR loci (D16S539 and TH01) and the Amelogenin marker. The detection of the Y allele in samples could provide a useful tool in the triage and submission of sexual assault samples by enforcement authorities. Male template material was detected on a range of common sexual assault evidence items including cotton pillow cases, condoms, swab heads and glass surfaces and shows a detection limit of 1 in 1000 dilution of neat semen. These data indicate this technology has the potential to be a useful tool for the detection of male donor DNA in sexual assault casework. © 2015 American Academy of Forensic Sciences.

  11. Developmental validation of the PowerPlex(®) ESI 16 and PowerPlex(®) ESI 17 Systems: STR multiplexes for the new European standard.

    PubMed

    Tucker, Valerie C; Hopwood, Andrew J; Sprecher, Cynthia J; McLaren, Robert S; Rabbach, Dawn R; Ensenberger, Martin G; Thompson, Jonelle M; Storts, Douglas R

    2011-11-01

    In response to the ENFSI and EDNAP groups' call for new STR multiplexes for Europe, Promega(®) developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex(®) ESI 16 (European Standard Investigator 16) and the PowerPlex(®) ESI 17 Systems. The PowerPlex(®) ESI 16 System combines the 11 loci compatible with the UK National DNA Database(®), contained within the AmpFlSTR(®) SGM Plus(®) PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR(®) SGM Plus(®) kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex(®) ESI 17 System amplifies the same loci as the PowerPlex(®) ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR(®) SGM Plus(®) kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex(®) ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54-86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  12. Tumoural specimens for forensic purposes: comparison of genetic alterations in frozen and formalin-fixed paraffin-embedded tissues.

    PubMed

    Ananian, Viviana; Tozzo, Pamela; Ponzano, Elena; Nitti, Donato; Rodriguez, Daniele; Caenazzo, Luciana

    2011-05-01

    In certain circumstances, tumour tissue specimens are the only DNA resource available for forensic DNA analysis. However, cancer tissues can show microsatellite instability and loss of heterozygosity which, if concerning the short tandem repeats (STRs) used in the forensic field, can cause misinterpretation of the results. Moreover, though formalin-fixed paraffin-embedded tissues (FFPET) represent a large resource for these analyses, the quality of the DNA obtained from this kind of specimen can be an important limit. In this study, we evaluated the use of tumoural tissue as biological material for the determination of genetic profiles in the forensic field, highlighting which STR polymorphisms are more susceptible to tumour genetic alterations and which of the analysed tumours show a higher genetic variability. The analyses were conducted on samples of the same tissues conserved in different storage conditions, to compare genetic profiles obtained by frozen tissues and formalin-fixed paraffin-embedded tissues. The importance of this study is due to the large number of specimens analysed (122), the large number of polymorphisms analysed for each specimen (39), and the possibility to compare, many years after storage, the same tissue frozen and formalin-fixed paraffin-embedded. In the comparison between the genetic profiles of frozen tumour tissues and FFPET, the same genetic alterations have been reported in both kinds of specimens. However, FFPET showed new alterations. We conclude that the use of FFPET requires greater attention than frozen tissues in the results interpretation and great care in both pre-extraction and extraction processes.

  13. Forensic DNA Banding Patterns: How to Simulate & Explain DNA Fingerprinting in a Classroom with No Budget

    ERIC Educational Resources Information Center

    Christensen, Doug

    2013-01-01

    Understanding how DNA banding patterns in a gel can aid in the conviction or exoneration of suspects and be utilized for positive identification of biological fathers in paternity cases can be intimidating. In reality, the logistics and technology used in such cases are rather straightforward. This exercise is designed for use in high school…

  14. DNA Fingerprint Analysis of Three Short Tandem Repeat (STR) Loci for Biochemistry and Forensic Science Laboratory Courses

    ERIC Educational Resources Information Center

    McNamara-Schroeder, Kathleen; Olonan, Cheryl; Chu, Simon; Montoya, Maria C.; Alviri, Mahta; Ginty, Shannon; Love, John J.

    2006-01-01

    We have devised and implemented a DNA fingerprinting module for an upper division undergraduate laboratory based on the amplification and analysis of three of the 13 short tandem repeat loci that are required by the Federal Bureau of Investigation Combined DNA Index System (FBI CODIS) data base. Students first collect human epithelial (cheek)…

  15. Evaluating forensic biology results given source level propositions.

    PubMed

    Taylor, Duncan; Abarno, Damien; Hicks, Tacha; Champod, Christophe

    2016-03-01

    The evaluation of forensic evidence can occur at any level within the hierarchy of propositions depending on the question being asked and the amount and type of information that is taken into account within the evaluation. Commonly DNA evidence is reported given propositions that deal with the sub-source level in the hierarchy, which deals only with the possibility that a nominated individual is a source of DNA in a trace (or contributor to the DNA in the case of a mixed DNA trace). We explore the use of information obtained from examinations, presumptive and discriminating tests for body fluids, DNA concentrations and some case circumstances within a Bayesian network in order to provide assistance to the Courts that have to consider propositions at source level. We use a scenario in which the presence of blood is of interest as an exemplar and consider how DNA profiling results and the potential for laboratory error can be taken into account. We finish with examples of how the results of these reports could be presented in court using either numerical values or verbal descriptions of the results. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  16. Forensic SNP genotyping with SNaPshot: Technical considerations for the development and optimization of multiplexed SNP assays.

    PubMed

    Fondevila, M; Børsting, C; Phillips, C; de la Puente, M; Consortium, Euroforen-NoE; Carracedo, A; Morling, N; Lareu, M V

    2017-01-01

    This review explores the key factors that influence the optimization, routine use, and profile interpretation of the SNaPshot single-base extension (SBE) system applied to forensic single-nucleotide polymorphism (SNP) genotyping. Despite being a mainly complimentary DNA genotyping technique to routine STR profiling, use of SNaPshot is an important part of the development of SNP sets for a wide range of forensic applications with these markers, from genotyping highly degraded DNA with very short amplicons to the introduction of SNPs to ascertain the ancestry and physical characteristics of an unidentified contact trace donor. However, this technology, as resourceful as it is, displays several features that depart from the usual STR genotyping far enough to demand a certain degree of expertise from the forensic analyst before tackling the complex casework on which SNaPshot application provides an advantage. In order to provide the basis for developing such expertise, we cover in this paper the most challenging aspects of the SNaPshot technology, focusing on the steps taken to design primer sets, optimize the PCR and single-base extension chemistries, and the important features of the peak patterns observed in typical forensic SNP profiles using SNaPshot. With that purpose in mind, we provide guidelines and troubleshooting for multiplex-SNaPshot-oriented primer design and the resulting capillary electrophoresis (CE) profile interpretation (covering the most commonly observed artifacts and expected departures from the ideal conditions). Copyright © 2017 Central Police University.

  17. The importance of scientific evaluation of biological evidence--data from eight years of case review.

    PubMed

    Coyle, Heather Miller

    2012-12-01

    In 2009, the National Research Council published a report stating that the addition of more science and technology into the field of forensic science in the United States would be of great benefit to the judicial system. As a starting point to address this NRC report, one needs to make an assessment of the system. One factor that is continuously requested is an estimate of an error rate. In any given scientific area of forensics that is difficult to quantitate except by external review and audits. After eight years of requested defense review of cases with biological and DNA evidence, most cases appear to be scientifically sound in test methods and procedures. However, there were some cases where errors in the forensic science process did occur. This article takes information compiled from those eight years of defense review and summarizes the cases where errors have been discovered and discusses the scientific implications of these errors. The scope of this article is limited to crime scene collection and forensic science laboratory testing of biological materials for body fluid identification and DNA individualization to a source. The greatest value of defense review comes from (a) providing effective balance and independent oversight to the judicial process and (b) collecting data into a format that can be useful as a guide in training programs. Copyright © 2012 Forensic Science Society. Published by Elsevier Ireland Ltd. All rights reserved.

  18. A male and female RNA marker to infer sex in forensic analysis.

    PubMed

    van den Berge, M; Sijen, T

    2017-01-01

    In forensics, DNA profiling is used for the identification of the donor of a trace, while messenger RNA (mRNA) profiling can be applied to identify the cellular origin such as body fluids or organ tissues. The presence of male cell material can be readily assessed by the incorporation of Y-chromosomal markers in quantitation or STR profiling systems. However, no forensic marker exists to positively identify female cell material; merely the presence of female DNA is deduced from the absence of a Y peak, or unbalanced X-Y signals at the Amelogenin locus or unbalanced response of the total and Y-specific quantifier. The presence of two X-chromosomes in female cells invokes dosage compensation, which is achieved through inactivation of one of the X-chromosomes in females. Since this process involves specific RNA molecules, identification of female cellular material may be possible through RNA profiling. Additionally, male material may be identified through RNAs expressed from the Y-chromosome. RNAs preferentially expressed in either sex were assessed for their potential to act as sex markers in forensic RNA assays. To confirm sex-specificity, body fluids and organ tissues of multiple donors of either sex were tested. Additionally, sensitivity of the markers and the suitability of positively identifying male-female mixtures were assessed and degraded samples were used to assess performance of the markers in forensic settings. The addition of sex-specific markers is of added informative value in any RNA profiling system and both markers were incorporated into existing RNA assays that either target body fluids or organs. These are the first forensic assays that enable positive identification of female cellular material. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. New perspectives in forensic anthropology.

    PubMed

    Dirkmaat, Dennis C; Cabo, Luis L; Ousley, Stephen D; Symes, Steven A

    2008-01-01

    A critical review of the conceptual and practical evolution of forensic anthropology during the last two decades serves to identify two key external factors and four tightly inter-related internal methodological advances that have significantly affected the discipline. These key developments have not only altered the current practice of forensic anthropology, but also its goals, objectives, scope, and definition. The development of DNA analysis techniques served to undermine the classic role of forensic anthropology as a field almost exclusively focused on victim identification. The introduction of the Daubert criteria in the courtroom presentation of scientific testimony accompanied the development of new human comparative samples and tools for data analysis and sharing, resulting in a vastly enhanced role for quantitative methods in human skeletal analysis. Additionally, new questions asked of forensic anthropologists, beyond identity, required sound scientific bases and expanded the scope of the field. This environment favored the incipient development of the interrelated fields of forensic taphonomy, forensic archaeology, and forensic trauma analysis, fields concerned with the reconstruction of events surrounding death. Far from representing the mere addition of new methodological techniques, these disciplines (especially, forensic taphonomy) provide forensic anthropology with a new conceptual framework, which is broader, deeper, and more solidly entrenched in the natural sciences. It is argued that this new framework represents a true paradigm shift, as it modifies not only the way in which classic forensic anthropological questions are answered, but also the goals and tasks of forensic anthropologists, and their perception of what can be considered a legitimate question or problem to be answered within the field.

  20. Eight years of psychiatric examination of detainees by forensic physicians in the Netherlands.

    PubMed

    van den Hondel, Karen E; Saaltink, Anne Linde; Bender, Peter Paul M

    2016-11-01

    Forensic physicians are responsible for first-line medical care of detainees (individuals held in custody) in the police station. The Dutch police law contains a 'duty of care', which gives the police responsibility for the apparent mentally ill and/or confused people they encounter during their work. The police can ask a forensic physician to do a primary psychiatric assessment of any apparent mentally ill detainee. The forensic physician determines if the apparent mentally ill behavior of the detainee is due to a somatic illness, or has a psychiatric cause for which the detainee needs admission to a psychiatric hospital. The forensic physician consults the second-line Public Mental Health Care (PMHC). This study aims to give an overview of the outcomes of psychiatric assessments of apparent mentally ill detainees in police stations. These assessments were done by forensic physicians over a period of eight years (2005-2013). A distinction is made between mental disorders, social problems, and alcohol/drugs abuse. All psychiatric assessments were registered in a medical database. When a secondary public mental health care assessment was performed, the conclusions and/or written feedback were received and included in the medical database. This information was used for this retrospective observational study. Of all the apparent mentally ill individuals brought by the police into the police station, the forensic physician sent home or referred 51.8% to their own respective caretakers or the individuals were voluntarily admitted to addiction care or other care facilities. When the forensic physician referred a detainee to PMHC, a compulsory admission to a psychiatric hospital was indicated by PMHC in 62.8% of the cases. Ultimately, of the total apparent mentally ill individuals brought in by the police 30.0% was admitted to a psychiatric hospital. Many apparent mentally ill individuals brought to the police station are sent home by the forensic physician. Before the psychiatric assessment, medical causes of psychiatric illnesses, for example excited delirium syndrome and hypoglycemia, drug use (GHB, cocaine, heroin), and cerebral pathology are excluded. The police perform as one of the channels through which the mentally ill get entrance to mental health care. Our data show no changes in the number of psychiatric assessments during 2005-2013. Copyright © 2016 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.

  1. Classification of Ancient Mammal Individuals Using Dental Pulp MALDI-TOF MS Peptide Profiling

    PubMed Central

    Tran, Thi-Nguyen-Ny; Aboudharam, Gérard; Gardeisen, Armelle; Davoust, Bernard; Bocquet-Appel, Jean-Pierre; Flaudrops, Christophe; Belghazi, Maya; Raoult, Didier; Drancourt, Michel

    2011-01-01

    Background The classification of ancient animal corpses at the species level remains a challenging task for forensic scientists and anthropologists. Severe damage and mixed, tiny pieces originating from several skeletons may render morphological classification virtually impossible. Standard approaches are based on sequencing mitochondrial and nuclear targets. Methodology/Principal Findings We present a method that can accurately classify mammalian species using dental pulp and mass spectrometry peptide profiling. Our work was organized into three successive steps. First, after extracting proteins from the dental pulp collected from 37 modern individuals representing 13 mammalian species, trypsin-digested peptides were used for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry analysis. The resulting peptide profiles accurately classified every individual at the species level in agreement with parallel cytochrome b gene sequencing gold standard. Second, using a 279–modern spectrum database, we blindly classified 33 of 37 teeth collected in 37 modern individuals (89.1%). Third, we classified 10 of 18 teeth (56%) collected in 15 ancient individuals representing five mammal species including human, from five burial sites dating back 8,500 years. Further comparison with an upgraded database comprising ancient specimen profiles yielded 100% classification in ancient teeth. Peptide sequencing yield 4 and 16 different non-keratin proteins including collagen (alpha-1 type I and alpha-2 type I) in human ancient and modern dental pulp, respectively. Conclusions/Significance Mass spectrometry peptide profiling of the dental pulp is a new approach that can be added to the arsenal of species classification tools for forensics and anthropology as a complementary method to DNA sequencing. The dental pulp is a new source for collagen and other proteins for the species classification of modern and ancient mammal individuals. PMID:21364886

  2. Pattern Recognition-Assisted Infrared Library Searching of the Paint Data Query Database to Enhance Lead Information from Automotive Paint Trace Evidence.

    PubMed

    Lavine, Barry K; White, Collin G; Allen, Matthew D; Weakley, Andrew

    2017-03-01

    Multilayered automotive paint fragments, which are one of the most complex materials encountered in the forensic science laboratory, provide crucial links in criminal investigations and prosecutions. To determine the origin of these paint fragments, forensic automotive paint examiners have turned to the paint data query (PDQ) database, which allows the forensic examiner to compare the layer sequence and color, texture, and composition of the sample to paint systems of the original equipment manufacturer (OEM). However, modern automotive paints have a thin color coat and this layer on a microscopic fragment is often too thin to obtain accurate chemical and topcoat color information. A search engine has been developed for the infrared (IR) spectral libraries of the PDQ database in an effort to improve discrimination capability and permit quantification of discrimination power for OEM automotive paint comparisons. The similarity of IR spectra of the corresponding layers of various records for original finishes in the PDQ database often results in poor discrimination using commercial library search algorithms. A pattern recognition approach employing pre-filters and a cross-correlation library search algorithm that performs both a forward and backward search has been used to significantly improve the discrimination of IR spectra in the PDQ database and thus improve the accuracy of the search. This improvement permits inter-comparison of OEM automotive paint layer systems using the IR spectra alone. Such information can serve to quantify the discrimination power of the original automotive paint encountered in casework and further efforts to succinctly communicate trace evidence to the courts.

  3. Target capture enrichment of nuclear SNP markers for massively parallel sequencing of degraded and mixed samples.

    PubMed

    Bose, Nikhil; Carlberg, Katie; Sensabaugh, George; Erlich, Henry; Calloway, Cassandra

    2018-05-01

    DNA from biological forensic samples can be highly fragmented and present in limited quantity. When DNA is highly fragmented, conventional PCR based Short Tandem Repeat (STR) analysis may fail as primer binding sites may not be present on a single template molecule. Single Nucleotide Polymorphisms (SNPs) can serve as an alternative type of genetic marker for analysis of degraded samples because the targeted variation is a single base. However, conventional PCR based SNP analysis methods still require intact primer binding sites for target amplification. Recently, probe capture methods for targeted enrichment have shown success in recovering degraded DNA as well as DNA from ancient bone samples using next-generation sequencing (NGS) technologies. The goal of this study was to design and test a probe capture assay targeting forensically relevant nuclear SNP markers for clonal and massively parallel sequencing (MPS) of degraded and limited DNA samples as well as mixtures. A set of 411 polymorphic markers totaling 451 nuclear SNPs (375 SNPs and 36 microhaplotype markers) was selected for the custom probe capture panel. The SNP markers were selected for a broad range of forensic applications including human individual identification, kinship, and lineage analysis as well as for mixture analysis. Performance of the custom SNP probe capture NGS assay was characterized by analyzing read depth and heterozygote allele balance across 15 samples at 25 ng input DNA. Performance thresholds were established based on read depth ≥500X and heterozygote allele balance within ±10% deviation from 50:50, which was observed for 426 out of 451 SNPs. These 426 SNPs were analyzed in size selected samples (at ≤75 bp, ≤100 bp, ≤150 bp, ≤200 bp, and ≤250 bp) as well as mock degraded samples fragmented to an average of 150 bp. Samples selected for ≤75 bp exhibited 99-100% reportable SNPs across varied DNA amounts and as low as 0.5 ng. Mock degraded samples at 1 ng and 10 ng exhibited >90% reportable SNPs. Finally, two-person male-male mixtures were tested at 10 ng in contributor varying ratios. Overall, 85-100% of alleles unique to the minor contributor were observed at all mixture ratios. Results from these studies using the SNP probe capture NGS system demonstrates proof of concept for application to forensically relevant degraded and mixed DNA samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Multiple Representations-Based Face Sketch-Photo Synthesis.

    PubMed

    Peng, Chunlei; Gao, Xinbo; Wang, Nannan; Tao, Dacheng; Li, Xuelong; Li, Jie

    2016-11-01

    Face sketch-photo synthesis plays an important role in law enforcement and digital entertainment. Most of the existing methods only use pixel intensities as the feature. Since face images can be described using features from multiple aspects, this paper presents a novel multiple representations-based face sketch-photo-synthesis method that adaptively combines multiple representations to represent an image patch. In particular, it combines multiple features from face images processed using multiple filters and deploys Markov networks to exploit the interacting relationships between the neighboring image patches. The proposed framework could be solved using an alternating optimization strategy and it normally converges in only five outer iterations in the experiments. Our experimental results on the Chinese University of Hong Kong (CUHK) face sketch database, celebrity photos, CUHK Face Sketch FERET Database, IIIT-D Viewed Sketch Database, and forensic sketches demonstrate the effectiveness of our method for face sketch-photo synthesis. In addition, cross-database and database-dependent style-synthesis evaluations demonstrate the generalizability of this novel method and suggest promising solutions for face identification in forensic science.

  5. DNA-Based Identification of Forensically Important Blow Flies (Diptera: Calliphoridae) From India.

    PubMed

    Bharti, Meenakshi; Singh, Baneshwar

    2017-09-01

    Correct species identification is the first and the most important criteria in entomological evidence-based postmortem interval (PMI) estimation. Although morphological keys are available for species identification of adult blow flies, keys for immature stages are either lacking or are incomplete. In this study, cytochrome oxidase subunit 1 (COI) reference data were developed from nine species (belonging to three subfamilies, namely, Calliphorinae, Luciliinae, and Chrysomyinae) of blow flies from India. Seven of the nine species included in this study were found suitable for DNA-based identification using COI gene, because they showed nonoverlapping intra- (0.0-0.3%) and inter-(1.96-18.14%) specific diversity, and formed well-supported monophyletic clade in phylogenetic analysis. The remaining two species (i.e., Chrysomya megacephala (Fabricius) and Chrysomya chani Kurahashi) cannot be distinguished reliably using our database because they had a very low interspecific diversity (0.11%), and Ch. megacephala was paraphyletic with respect to Ch. chani in the phylogenetic analysis. We conclude that the COI gene is a useful marker for DNA-based identification of blow flies from India. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  6. Final Report: The DNA Files: Unraveling the mysteries of genetics, January 1, 1998-March 31, 1999

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scott, Bari

    1999-05-01

    The DNA Files is an award-winning radio documentary series on genetics created by SoundVision Productions. The DNA Files was hosted by John Hockenberry and was presented in documentary and discussion format. The programs covered a range of topics from prenatal and predictive gene testing, gene therapy, and commercialization of genetic information to new evolutionary genetic evidence, transgenic vegetables and use of DNA in forensics.

  7. [The proof of paternity. An andrological-forensic challenge in historical perspective].

    PubMed

    Albrecht, K; Schultheiss, D

    2004-10-01

    For centuries, difficulties have occurred in determining unresolved paternities. In addition to the modern standard methods, such as the examination of DNA or serological proof, expert opinion on fertility once played an important role. The andrological difference between incapability to fertilise and the inability to participate in sexual intercourse was also distinguished historically. Of special significance was the discovery of spermatozoa by the medical student Johan Ham in 1677 and their further investigation by Antoni van Leeuwenhoek.Recently, modern DNA methods have also been applied for historical investigations. Illustrious examples are the DNA analysis in the case of Kaspar Hauser of Ansbach and the dispute about Thomas Jefferson, President of the U.S., fathering a child by one of his slaves. In this discourse, a medicinal-forensic review of the development of expert opinion, illustrated with historical case studies, is given.

  8. Development of a rapid 21-plex autosomal STR typing system for forensic applications.

    PubMed

    Yang, Meng; Yin, Caiyong; Lv, Yuexin; Yang, Yaran; Chen, Jing; Yu, Zailiang; Liu, Xu; Xu, Meibo; Chen, Feng; Wu, Huijuan; Yan, Jiangwei

    2016-10-01

    DNA-STR genotyping technology has been widely used in forensic investigations. Even with such success, there is a great need to reduce the analysis time. In this study, we established a new rapid 21-plex STR typing system, including 13 CODIS loci, Penta D, Penta E, D12S391, D2S1338, D6S1043, D19S433, D2S441 and Amelogenin loci. This system could shorten the amplification time to a minimum of 90 min and does not require DNA extraction from the samples. Validation of the typing system complied with the Scientific Working Group on DNA Analysis Methods (SWGDAM) and the Chinese National Standard (GA/T815-2009) guidelines. The results demonstrated that this 21-plex STR typing system was a valuable tool for rapid criminal investigation. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Forensic discrimination of vaginal epithelia by DNA methylation analysis through pyrosequencing.

    PubMed

    Antunes, Joana; Silva, Deborah S B S; Balamurugan, Kuppareddi; Duncan, George; Alho, Clarice S; McCord, Bruce

    2016-10-01

    The accurate identification of body fluids from crime scenes can aid in the discrimination between criminal and innocent intent. This research aimed to determine if the levels of DNA methylation in the locus PFN3A could be used to discriminate vaginal epithelia from other body fluids. In this work we bisulfite-modified and amplified DNA samples from blood, saliva, semen, and vaginal epithelia using primers for PFN3A. Through pyrosequencing we were able to show that vaginal epithelia present distinct methylation levels when compared to other body fluids. Mixtures of different body fluids present methylation values that correlate with single-source body fluid samples and the primers for PFN3A are specific for primates. This report successfully demonstrated that the analysis of methylation in the PFN3A locus can be used for vaginal epithelia discrimination in forensic samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Effects of the Ion PGM™ Hi-Q™ sequencing chemistry on sequence data quality.

    PubMed

    Churchill, Jennifer D; King, Jonathan L; Chakraborty, Ranajit; Budowle, Bruce

    2016-09-01

    Massively parallel sequencing (MPS) offers substantial improvements over current forensic DNA typing methodologies such as increased resolution, scalability, and throughput. The Ion PGM™ is a promising MPS platform for analysis of forensic biological evidence. The system employs a sequencing-by-synthesis chemistry on a semiconductor chip that measures a pH change due to the release of hydrogen ions as nucleotides are incorporated into the growing DNA strands. However, implementation of MPS into forensic laboratories requires a robust chemistry. Ion Torrent's Hi-Q™ Sequencing Chemistry was evaluated to determine if it could improve on the quality of the generated sequence data in association with selected genetic marker targets. The whole mitochondrial genome and the HID-Ion STR 10-plex panel were sequenced on the Ion PGM™ system with the Ion PGM™ Sequencing 400 Kit and the Ion PGM™ Hi-Q™ Sequencing Kit. Concordance, coverage, strand balance, noise, and deletion ratios were assessed in evaluating the performance of the Ion PGM™ Hi-Q™ Sequencing Kit. The results indicate that reliable, accurate data are generated and that sequencing through homopolymeric regions can be improved with the use of Ion Torrent's Hi-Q™ Sequencing Chemistry. Overall, the quality of the generated sequencing data supports the potential for use of the Ion PGM™ in forensic genetic laboratories.

  11. Using DNA-barcoding to make the necrobiont beetle family Cholevidae accessible for forensic entomology.

    PubMed

    Schilthuizen, Menno; Scholte, Cindy; van Wijk, Renske E J; Dommershuijzen, Jessy; van der Horst, Devi; Zu Schlochtern, Melanie Meijer; Lievers, Rik; Groenenberg, Dick S J

    2011-07-15

    The beetle family Cholevidae (Coleoptera: Staphylinoidea), sometimes viewed as the subfamily Cholevinae of the Leiodidae, consists of some 1700 species worldwide. With the exception of specialized cave-dwelling species and species living in bird and mammal nests and burrows, the species are generalized soil-dwellers that, at least in temperate regions, are mostly found on vertebrate cadavers. Although they have been regularly reported from human corpses, and offer potential because of many species' peak activity in the cold season, they have not been a focus of forensic entomologists so far. This is probably due to their small size and the difficulty in identifying the adults and their larvae. In this paper, we show that DNA-barcoding can help make this group of necrobiont beetles available as a tool for forensic research. We collected 86 specimens of 20 species of the genera Catops, Fissocatops, Apocatops, Choleva, Nargus, Ptomaphagus, and Sciodrepoides from the Netherlands and France and show that a broad "barcoding gap" allows almost all species to be easily and unambiguously identified by the sequence of the "barcoding gene" cytochrome c oxidase I (COI). This opens up the possibility of adding Cholevidae to the set of insect taxa routinely used in forensic entomology. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  12. Microbial forensics: the next forensic challenge.

    PubMed

    Budowle, Bruce; Murch, Randall; Chakraborty, Ranajit

    2005-11-01

    Pathogens and toxins can be converted to bioweapons and used to commit bioterrorism and biocrime. Because of the potential and relative ease of an attack using a bioweapon, forensic science needs to be prepared to assist in the investigation to bring perpetrators to justice and to deter future attacks. A new subfield of forensics--microbial forensics--has been created, which is focused on characterization of evidence from a bioterrorism act, biocrime, hoax, or an inadvertent release. Forensic microbiological investigations are essentially the same as any other forensic investigation regarding processing. They involve crime scene(s) investigation, chain of custody practices, evidence collection, handling and preservation, evidence shipping, analysis of evidence, interpretation of results, and court presentation. In addition to collecting and analyzing traditional forensic evidence, the forensic investigation will attempt to determine the etiology and identity of the causal agent, often in a similar fashion as in an epidemiologic investigation. However, for attribution, higher-resolution characterization is needed. The tools for attribution include genetic- and nongenetic-based assays and informatics to attempt to determine the unique source of a sample or at least eliminate some sources. In addition, chemical and physical assays may help determine the process used to prepare, store, or disseminate the bioweapon. An effective microbial forensics program will require development and/or validation of all aspects of the forensic investigative process, from sample collection to interpretation of results. Quality assurance (QA) and QC practices, comparable to those used by the forensic DNA science community, are being implemented. Lastly, partnerships with other laboratories will be requisite, because many of the necessary capabilities for analysis will not reside in the traditional forensic laboratory.

  13. On detection of median filtering in digital images

    NASA Astrophysics Data System (ADS)

    Kirchner, Matthias; Fridrich, Jessica

    2010-01-01

    In digital image forensics, it is generally accepted that intentional manipulations of the image content are most critical and hence numerous forensic methods focus on the detection of such 'malicious' post-processing. However, it is also beneficial to know as much as possible about the general processing history of an image, including content-preserving operations, since they can affect the reliability of forensic methods in various ways. In this paper, we present a simple yet effective technique to detect median filtering in digital images-a widely used denoising and smoothing operator. As a great variety of forensic methods relies on some kind of a linearity assumption, a detection of non-linear median filtering is of particular interest. The effectiveness of our method is backed with experimental evidence on a large image database.

  14. A set of 14 DIP-SNP markers to detect unbalanced DNA mixtures.

    PubMed

    Liu, Zhizhen; Liu, Jinding; Wang, Jiaqi; Chen, Deqing; Liu, Zidong; Shi, Jie; Li, Zeqin; Li, Wenyan; Zhang, Gengqian; Du, Bing

    2018-03-04

    Unbalanced DNA mixture is still a difficult problem for forensic practice. DIP-STRs are useful markers for detection of minor DNA but they are not widespread in the human genome and having long amplicons. In this study, we proposed a novel type of genetic marker, termed DIP-SNP. DIP-SNP refers to the combination of INDEL and SNP in less than 300bp length of human genome. The multiplex PCR and SNaPshot assay were established for 14 DIP-SNP markers in a Chinese Han population from Shanxi, China. This novel compound marker allows detection of the minor DNA contributor with sensitivity from 1:50 to 1:1000 in a DNA mixture of any gender with 1 ng-10 ng DNA template. Most of the DIP-SNP markers had a relatively high probability of informative alleles with an average I value of 0.33. In all, we proposed DIP-SNP as a novel kind of genetic marker for detection of minor contributor from unbalanced DNA mixture and established the detection method by associating the multiplex PCR and SNaPshot assay. DIP-SNP polymorphisms are promising markers for forensic or clinical mixture examination because they are shorter, widespread and higher sensitive. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. Fast and simple DNA extraction from saliva and sperm cells obtained from the skin or isolated from swabs.

    PubMed

    von Wurmb-Schwark, Nicole; Mályusz, Victoria; Fremdt, Heike; Koch, Christine; Simeoni, Eva; Schwark, Thorsten

    2006-05-01

    The forensic scientist often has to cope with problematic samples from the crime scene due to their minute size and thus the low amount of extractable DNA. The retrieval of DNA from swabs taken from the surface of the skin, for example, in cases of strangulation, can be especially difficult. We systematically investigated swabs taken from the skin (to obtain a genetic profile from the victim and also from a possible offender) and from sperm cell containing swabs using two extraction kits: the Invisorb forensic and the Invisorb spin swab kit (both Invitek, Germany). DNA quality and quantity were tested on ethidium bromide containing agarose gels and in a highly sensitive duplex-PCR, which amplifies fragments specific for mitochondrial and nuclear DNA. Absolute quantification was done using real time PCR. Samples, which were positive in the duplex-PCR, were also employed to genetic fingerprinting using the Powerplex ES and the AmpFlSTRIdentifiler(TM) kits. Our study shows that the easy-to-use Invisorb spin swab kit is very suitable for DNA isolation from swabs taken from the skin and also from sperm cells. Retrieval of cells from the skin with swabs moistened in extraction buffer, not in distilled water, led to a significant higher DNA yield.

  16. Rapid ABO genotyping by high-speed droplet allele-specific PCR using crude samples.

    PubMed

    Taira, Chiaki; Matsuda, Kazuyuki; Takeichi, Naoya; Furukawa, Satomi; Sugano, Mitsutoshi; Uehara, Takeshi; Okumura, Nobuo; Honda, Takayuki

    2018-01-01

    ABO genotyping has common tools for personal identification of forensic and transplantation field. We developed a new method based on a droplet allele-specific PCR (droplet-AS-PCR) that enabled rapid PCR amplification. We attempted rapid ABO genotyping using crude DNA isolated from dried blood and buccal cells. We designed allele-specific primers for three SNPs (at nucleotides 261, 526, and 803) in exons 6 and 7 of the ABO gene. We pretreated dried blood and buccal cells with proteinase K, and obtained crude DNAs without DNA purification. Droplet-AS-PCR allowed specific amplification of the SNPs at the three loci using crude DNA, with results similar to those for DNA extracted from fresh peripheral blood. The sensitivity of the methods was 5%-10%. The genotyping of extracted DNA and crude DNA were completed within 8 and 9 minutes, respectively. The genotypes determined by the droplet-AS-PCR method were always consistent with those obtained by direct sequencing. The droplet-AS-PCR method enabled rapid and specific amplification of three SNPs of the ABO gene from crude DNA treated with proteinase K. ABO genotyping by the droplet-AS-PCR has the potential to be applied to various fields including a forensic medicine and transplantation medical care. © 2017 Wiley Periodicals, Inc.

  17. Bacterial Population Genetics in a Forensic Context

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Velsko, S P

    This report addresses the recent Department of Homeland Security (DHS) call for a Phase I study to (1) assess gaps in the forensically relevant knowledge about the population genetics of eight bacterial agents of concern, (2) formulate a technical roadmap to address those gaps, and (3) identify new bioinformatics tools that would be necessary to analyze and interpret population genetic data in a forensic context. The eight organisms that were studied are B. anthracis, Y. pestis, F. tularensis, Brucella spp., E. coli O157/H7, Burkholderia mallei, Burkholderia pseudomallei, and C. botulinum. Our study focused on the use of bacterial population geneticsmore » by forensic investigators to test hypotheses about the possible provenance of an agent that was used in a crime or act of terrorism. Just as human population genetics underpins the calculations of match probabilities for human DNA evidence, bacterial population genetics determines the level of support that microbial DNA evidence provides for or against certain well-defined hypotheses about the origins of an infecting strain. Our key findings are: (1) Bacterial population genetics is critical for answering certain types of questions in a probabilistic manner, akin (but not identical) to 'match probabilities' in DNA forensics. (2) A basic theoretical framework for calculating likelihood ratios or posterior probabilities for forensic hypotheses based on microbial genetic comparisons has been formulated. This 'inference-on-networks' framework has deep but simple connections to the population genetics of mtDNA and Y-STRs in human DNA forensics. (3) The 'phylogeographic' approach to identifying microbial sources is not an adequate basis for understanding bacterial population genetics in a forensic context, and has limited utility, even for generating 'leads' with respect to strain origin. (4) A collection of genotyped isolates obtained opportunistically from international locations augmented by phylogenetic representations of relatedness will not and enzootic outbreaks noted through international outbreak surveillance systems, and 'representative' genetic sequences from each outbreak. (5) Interpretation of genetic comparisons between an attack strain and reference strains requires a model for the network structure of maintenance foci, enzootic outbreaks, and human outbreaks of that disease, coupled with estimates of mutational rate constants. Validation of the model requires a set of sequences from exemplary outbreaks and laboratory data on mutation rates during animal passage. The necessary number of isolates in each validation set is determined by disease transmission network theory, and is based on the 'network diameter' of the outbreak. (6) The 8 bacteria in this study can be classified into 4 categories based on the complexity of the transmission network structure of their natural maintenance foci and their outbreaks, both enzootic and zoonotic. (7) For B. anthracis, Y. pestis, E. coli O157, and Brucella melitensis, and their primary natural animal hosts, most of the fundamental parameters needed for modeling genetic change within natural host or human transmission networks have been determined or can be estimated from existing field and laboratory studies. (8) For Burkholderia mallei, plausible approaches to transmission network models exist, but much of the fundamental parameterization does not. In addition, a validated high-resolution typing system for characterizing genetic change within outbreaks or foci has not yet been demonstrated, although a candidate system exists. (9) For Francisella tularensis, the increased complexity of the transmission network and unresolved questions about maintenance and transmission suggest that it will be more complex and difficult to develop useful models based on currently available data. (10) For Burkholderia pseudomallei and Clostridium botulinum, the transmission and maintenance networks involve complex soil communities and metapopulations about which very little is known. It is not clear that these pathogens can be brought into the inference-on-networks framework without additional conceptual advances. (11) For all 8 bacteria some combination of field studies, computational modeling, and laboratory experiments are needed to provide a useful forensic capability for bacterial genetic inference.« less

  18. NGS-based likelihood ratio for identifying contributors in two- and three-person DNA mixtures.

    PubMed

    Chan Mun Wei, Joshua; Zhao, Zicheng; Li, Shuai Cheng; Ng, Yen Kaow

    2018-06-01

    DNA fingerprinting, also known as DNA profiling, serves as a standard procedure in forensics to identify a person by the short tandem repeat (STR) loci in their DNA. By comparing the STR loci between DNA samples, practitioners can calculate a probability of match to identity the contributors of a DNA mixture. Most existing methods are based on 13 core STR loci which were identified by the Federal Bureau of Investigation (FBI). Analyses based on these loci of DNA mixture for forensic purposes are highly variable in procedures, and suffer from subjectivity as well as bias in complex mixture interpretation. With the emergence of next-generation sequencing (NGS) technologies, the sequencing of billions of DNA molecules can be parallelized, thus greatly increasing throughput and reducing the associated costs. This allows the creation of new techniques that incorporate more loci to enable complex mixture interpretation. In this paper, we propose a computation for likelihood ratio that uses NGS (next generation sequencing) data for DNA testing on mixed samples. We have applied the method to 4480 simulated DNA mixtures, which consist of various mixture proportions of 8 unrelated whole-genome sequencing data. The results confirm the feasibility of utilizing NGS data in DNA mixture interpretations. We observed an average likelihood ratio as high as 285,978 for two-person mixtures. Using our method, all 224 identity tests for two-person mixtures and three-person mixtures were correctly identified. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. First all-in-one diagnostic tool for DNA intelligence: genome-wide inference of biogeographic ancestry, appearance, relatedness, and sex with the Identitas v1 Forensic Chip.

    PubMed

    Keating, Brendan; Bansal, Aruna T; Walsh, Susan; Millman, Jonathan; Newman, Jonathan; Kidd, Kenneth; Budowle, Bruce; Eisenberg, Arthur; Donfack, Joseph; Gasparini, Paolo; Budimlija, Zoran; Henders, Anjali K; Chandrupatla, Hareesh; Duffy, David L; Gordon, Scott D; Hysi, Pirro; Liu, Fan; Medland, Sarah E; Rubin, Laurence; Martin, Nicholas G; Spector, Timothy D; Kayser, Manfred

    2013-05-01

    When a forensic DNA sample cannot be associated directly with a previously genotyped reference sample by standard short tandem repeat profiling, the investigation required for identifying perpetrators, victims, or missing persons can be both costly and time consuming. Here, we describe the outcome of a collaborative study using the Identitas Version 1 (v1) Forensic Chip, the first commercially available all-in-one tool dedicated to the concept of developing intelligence leads based on DNA. The chip allows parallel interrogation of 201,173 genome-wide autosomal, X-chromosomal, Y-chromosomal, and mitochondrial single nucleotide polymorphisms for inference of biogeographic ancestry, appearance, relatedness, and sex. The first assessment of the chip's performance was carried out on 3,196 blinded DNA samples of varying quantities and qualities, covering a wide range of biogeographic origin and eye/hair coloration as well as variation in relatedness and sex. Overall, 95 % of the samples (N = 3,034) passed quality checks with an overall genotype call rate >90 % on variable numbers of available recorded trait information. Predictions of sex, direct match, and first to third degree relatedness were highly accurate. Chip-based predictions of biparental continental ancestry were on average ~94 % correct (further support provided by separately inferred patrilineal and matrilineal ancestry). Predictions of eye color were 85 % correct for brown and 70 % correct for blue eyes, and predictions of hair color were 72 % for brown, 63 % for blond, 58 % for black, and 48 % for red hair. From the 5 % of samples (N = 162) with <90 % call rate, 56 % yielded correct continental ancestry predictions while 7 % yielded sufficient genotypes to allow hair and eye color prediction. Our results demonstrate that the Identitas v1 Forensic Chip holds great promise for a wide range of applications including criminal investigations, missing person investigations, and for national security purposes.

  20. Forensic Science Research and Development at the National Institute of Justice: Opportunities in Applied Physics

    NASA Astrophysics Data System (ADS)

    Dutton, Gregory

    Forensic science is a collection of applied disciplines that draws from all branches of science. A key question in forensic analysis is: to what degree do a piece of evidence and a known reference sample share characteristics? Quantification of similarity, estimation of uncertainty, and determination of relevant population statistics are of current concern. A 2016 PCAST report questioned the foundational validity and the validity in practice of several forensic disciplines, including latent fingerprints, firearms comparisons and DNA mixture interpretation. One recommendation was the advancement of objective, automated comparison methods based on image analysis and machine learning. These concerns parallel the National Institute of Justice's ongoing R&D investments in applied chemistry, biology and physics. NIJ maintains a funding program spanning fundamental research with potential for forensic application to the validation of novel instruments and methods. Since 2009, NIJ has funded over 179M in external research to support the advancement of accuracy, validity and efficiency in the forensic sciences. An overview of NIJ's programs will be presented, with examples of relevant projects from fluid dynamics, 3D imaging, acoustics, and materials science.

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