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1.
Methods Mol Biol ; 2243: 355-368, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33606268

RESUMO

Recent scientific advancements in the field of genetics have fostered significant changes for the criminal justice system. Growing National DNA databases, public DNA databases, private direct-to-consumer (DTC) DNA testing companies, and improvements in next-generation sequencing (NGS) have resulted in effective methods for tracking down criminals and exonerating the innocent. While these recently discovered and profound techniques seem to provide benefits, their use in forensic detection has become subject to harsh legal opposition. Ultimately, should law enforcement be permitted to analyze DNA found at crime scenes and DNA that has accumulated in national, public, and private databases to aid in their investigations, or are individuals' privacy rights breached in the process?


Assuntos
DNA/genética , Genética Forense/métodos , Impressões Digitais de DNA/métodos , Análise de Dados , Coleta de Dados/métodos , Gerenciamento de Dados/métodos , Bases de Dados de Ácidos Nucleicos , Técnicas Genéticas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos
2.
Mol Biol Rep ; 48(2): 1667-1676, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33479828

RESUMO

Accurate species and sex identification of non-invasive and forensic samples of the tiger and leopard is still confusing when using the allele-specific methods. We designed allele-specific methods with penultimate nucleotide mismatch in a nested manner for the exact identification and double-checking of forensic samples. The mismatch design is a novel concept in species and sex identification, making the allele-specific targeting precise. We developed three sets of markers, a 365 bp outer and a 98 bp inner marker for nested tiger species identification assay, 136 bp leopard specific marker, and carnivore sex identification markers. We validated the method with tissue/blood forensic samples of various felids and herbivorous available in our lab and on known fecal samples from Vandalur Zoo. We also collected 37 scat samples at diverse stages of deterioration from the Mudumalai Tiger Reserve, Tamil Nadu, India. The 365 bp targeted markers resulted in 70.2% (n = 22; 22/37) amplification success, while the 98 bp FAM-labelled marker amplified 89% (n = 33; 33/37) scat samples independently. The 136 bp leopard markers answered four scat samples (11%) unrequited by the tiger specific markers. We evaluated species and the sex identification with these markers in another 190 non-invasive samples provided by the Mudumalai Tiger Reserve authorities. Among which 56.3% (n = 107) of samples were recognized as tiger (64 male and 43 female) and 38.9% (n = 74) as leopard (41 male and 33 female). The method supersedes any other previous methods in this regard by its high accuracy and simplicity.


Assuntos
Genética Forense/métodos , Panthera/genética , Reação em Cadeia da Polimerase/métodos , Tigres/genética , Alelos , Animais , Biomarcadores , Primers do DNA , Espécies em Perigo de Extinção , Feminino , Identidade de Gênero , Índia , Masculino , Panthera/sangue , Panthera/metabolismo , Sensibilidade e Especificidade , Especificidade da Espécie , Tigres/sangue , Tigres/metabolismo , Cromossomo X/genética , Cromossomo Y/genética
3.
Forensic Sci Int ; 320: 110682, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33461005

RESUMO

In 1932, seven burials were discovered on a Texas plantation that was originally the site of a 17th-century Caddo Indian village. Of the seven excavated graves, one set of remains (an adult male) was notably buried in a manner inconsistent with traditional Caddoan burial practices and has long been purported to be the remains of Sieur de Marle (a member of the French explorer La Salle's last expedition). Diary accounts of La Salle's expedition scribe report that Sieur de Marle died along a river near an Indian village during a trek to Canada to find help for colonists left behind at the ill-fated Fort St. Louis. Additionally, two lead projectiles recovered from the grave were ballistically analyzed and determined to be consistent with ammunition used in 17th-century weaponry. In the 1980s, anthropologists requested access to the remains for study, but the skull was missing. Cranial measurements recorded in 1940 and 1962 (by two independent anthropologists) were used to investigate the ancestry of this individual; and the Giles-Elliot (G-E) discriminant function was calculated to be 18.1, within the Anglo-European range. Dietary isotope testing on non-cranial skeletal elements determined that this unknown male's diet was rich in animal/marine protein sources, which differs appreciably from Caddo Indian populations of that time period. In order to genetically assess this individual's biogeographic ancestry and to provide further support that this individual is of European descent, mitochondrial DNA (mtDNA) sequencing was performed using the Applied Biosystems™ Precision ID mtDNA Whole Genome Panel. mtDNA sequencing of multiple sections from two different long bones yielded compiled results consistent with either Haplogroup H or R, both predominantly European mtDNA haplogroups. Further anthropological calculations were conducted using cranial measurements, FORDISC™ software, and discriminant function analysis. Two-way, four-way, and multigroup discriminant function analyses further classify this set of unidentified remains as being White (European) in origin, with posterior probabilities of 0.999, 0.881 and 0.986, respectively. Combined with historical records of Sieur de Marle's death, as well as overlays of historical and contemporary maps which demonstrate that the plantation site aligns with Joutel's diary accounts of de Marle's burial, these collective results support that these remains are of a European male and may possibly belong to this prominent member of La Salle's expedition team.


Assuntos
Nativos Estadunidenses , Restos Mortais , DNA Mitocondrial/genética , Grupo com Ancestrais do Continente Europeu , Nativos Estadunidenses/genética , Sepultamento , Cefalometria , Análise Discriminante , Grupo com Ancestrais do Continente Europeu/genética , Antropologia Forense/métodos , Genética Forense/métodos , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Reação em Cadeia da Polimerase , Texas
4.
Forensic Sci Int ; 319: 110638, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33340848

RESUMO

Working with mitochondrial DNA from highly degraded samples is challenging. We present a whole mitogenome Illumina-based sequencing method suitable for highly degraded samples. The method makes use of double-stranded library preparation with hybridization-based target enrichment. The aim of the study was to implement a new user-friendly method for analysing many ancient DNA samples at low cost. The method combines the Swift 2S™ Turbo library preparation kit and xGen® panel for mitogenome enrichment. Swift allows to use low input of aDNA and own adapters and primers, handles inhibitors well, and has only two purification steps. xGen is straightforward to use and is able to leverage already pooled libraries. Given the ancient DNA is more challenging to work with, the protocol was developed with several improvements, especially multiplying DNA input in case of low concentration DNA extractions followed by AMPure® beads size selection and real-time pre-capture PCR monitoring in order to avoid cycle-optimization step. Nine out of eleven analysed samples successfully retrieved mitogenomes. Hence, our method provides an effective analysis of whole mtDNA, and has proven to be fast, cost-effective, straightforward, with utilisation in population-wide research of burial sites.


Assuntos
DNA Antigo , DNA Mitocondrial/genética , Genoma Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise Custo-Benefício , Genética Forense/métodos , Humanos , Reação em Cadeia da Polimerase
5.
Rev. esp. med. legal ; 46(4): 183-190, oct.-dic. 2020.
Artigo em Espanhol | IBECS | ID: ibc-200511

RESUMO

El fenotipado de ADN forense mediante massive parallel sequencing es una técnica emergente dentro del campo de la genética forense, que permite predecir características visibles del individuo a partir del ADN. Esta herramienta se ha convertido en una de las más potentes para ayudar a estrechar el cerco investigativo en diferentes casos forenses. Hasta ahora el color de ojos, de piel y de pelo son los rasgos fenotípicos que se pueden predecir con la suficiente precisión y fiabilidad como para usarlos en la práctica forense. Sin embargo, esta técnica no está implementada todavía de manera rutinaria en este campo debido, principalmente, a la falta de conocimiento genético completo sobre la pigmentación y los rasgos faciales humanos; y la menor predictibilidad de los fenotipos intermedios. Además, su aplicación en algunos países ha suscitado una serie de cuestiones éticas y sociales, así como legales, siendo estos últimos los más determinantes en la implementación de esta herramienta


Forensic DNA Phenotyping (FDP) based on massive parallel sequencing (MPS) is an emerging technique within Forensic Genetics that enables the prediction of an individual's externally visible characteristics (EVCs) from DNA. Because of its achievements, FDP has become one of the most useful additional tools for aiding police investigations to narrow down the investigative pool in different types of forensic cases. Eye, hair and skin colour can now be predicted reliably and with practically useful accuracy. However, FDP has not yet been routinely implemented in the forensic science field due to, principally, the lack of complete genetic knowledge of pigmentation and facial traits and the lower predictability of intermediate phenotypes. Furthermore, in some countries its application has given rise to a number of ethical, social and legal issues, the latter being the most restrictive barrier to the implementation of FDP


Assuntos
Humanos , Testes Genéticos/legislação & jurisprudência , Impressões Digitais de DNA/legislação & jurisprudência , Genética Forense/métodos , Fenótipo , Variação Biológica da População/genética , Bases de Dados de Ácidos Nucleicos/organização & administração , Sequenciamento Completo do Genoma/classificação
7.
Med Sci (Paris) ; 36(8-9): 813-816, 2020.
Artigo em Francês | MEDLINE | ID: mdl-32821057

RESUMO

The prediction of a person's aspect from analysis of an anonymous DNA sample has made significant progress in the last decade. Pigmentation (eyes, hair and, more recently, skin colour) can now be determined with good accuracy; face shape is still not amenable to prediction (except, in general lines, from ancestry). Age can apparently also be determined from methylation profiles. Police forces are, understandably, very interested in this technology, with a tendency to over-estimate its accuracy. Legislation varies greatly, with some nations opting for complete prohibition (Germany) and others allowing wide application of the approach (United Kingdom).


Assuntos
Genética Forense/tendências , Fenótipo , Adulto , Grupos Étnicos/genética , Genética Forense/métodos , Estudos de Associação Genética , Humanos , Recém-Nascido , Padrões de Herança/genética , Masculino , Polimorfismo de Nucleotídeo Único , Retratos como Assunto , Pigmentação da Pele/genética , Gêmeos/genética
9.
Leg Med (Tokyo) ; 47: 101741, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32682294

RESUMO

In present study, we evaluated the genetic diversities of 30 insertion/deletion (InDel) loci and analyzed the genetic relationships between Daur and other comparison populations. In the studied Daur group, any two InDel loci showed no linkage disequilibrium, and all loci showed no deviations from exact tests of Hardy-Weinberg equilibrium. Insertion allele frequencies at 30 InDel loci ranged from 0.1459 (HLD39) to 0.8774 (HLD118). The observed heterozygosity and expected heterozygosity values were ranged from 0.1984 (HLD118) to 0.5564 (HLD6) and 0.2155 (HLD118) to 0.5000 (HLD92 and HLD6), respectively. The combined power of discrimination and power of exclusion values were 0.999999999993428 and 0.9878, respectively, which indicated that this panel of 30 InDels could be used for individual identifications in Daur group. Population genetic analyses including pairwise fixation index, STRUCTURE analysis, principal component analysis, genetic distance, multidimensional scaling analysis and phylogenetic analysis demonstrated that the Daur group had the closer genetic relationships with the groups from western China in comparison with other continental populations.


Assuntos
Grupo com Ancestrais do Continente Asiático/genética , Grupos Étnicos/genética , Genética Forense/métodos , Frequência do Gene/genética , Loci Gênicos/genética , Variação Genética/genética , Genética Populacional/métodos , Mutação INDEL/genética , China/etnologia , Feminino , Heterozigoto , Humanos , Masculino
10.
Leg Med (Tokyo) ; 47: 101759, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32711370

RESUMO

Cannabis sativa can be classified as either hemp (a legal crop containing less than 0.3% delta-9-tetrahydrocannabinol, THC) or marijuana (an illegal drug containing more than 0.3% THC). Despite its legalization in 33 states for medicinal or recreational use, marijuana remains the most commonly used illicit drug in the USA, and it is heavily trafficked into and within the country. Discriminating between marijuana and hemp is critical to the legal process. Genetic analysis provides a means of analyzing samples unsuitable for chemical analysis, and in addition to discriminating between crop types, DNA may be able to determine the biogeographical origin of samples. In addition, the sharing of rare haplotypes between different seizures may be useful for linking cases and providing investigative leads to law enforcement. This study evaluates the potential of two highly polymorphic regions of the chloroplast genome of C. sativa, rps16 and clpP, to be used for determination of crop type and biogeographical origin. Custom fragment analysis and SNaPshot™ assays were developed to genotype nine polymorphic loci in hemp samples from the USA and Canada, marijuana samples from USA-Mexico and Chile, and medical marijuana samples from Chile. Haplotype analysis revealed eight haplotypes. Only Canadian hemp could be completely differentiated from the other sample groups by haplotype. Phylogenetic analysis and principal component analysis suggested a closer relationship among USA-Mexico marijuana, Chilean marijuana and medical marijuana, and USA hemp. Genotyping additional polymorphisms in future studies is expected to reveal further differences between these sample groups.


Assuntos
Cannabis/classificação , Cannabis/genética , Cloroplastos/genética , Produtos Agrícolas , Código de Barras de DNA Taxonômico/métodos , Genética Forense/métodos , Canadá , Cannabis/química , Chile , DNA de Plantas , Loci Gênicos , Genoma de Planta/genética , Genótipo , Haplótipos , México , Filogenia
11.
Leg Med (Tokyo) ; 47: 101763, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32721866

RESUMO

DNA methylation analysis in a variety of genes has brought promising results in age estimation. The main aim of this study was to evaluate DNA methylation levels from four age-correlated genes, ELOVL2, FHL2, EDARADD and PDE4C, in blood samples of healthy Portuguese individuals. Fifty-three samples were analyzed through the bisulfite polymerase chain reaction (PCR) sequencing method for CpG dinucleotide methylation status. Linear regression models were used to analyze relationships between methylation levels and chronological age. The highest age-associated CpG in each locus was chosen to build a multi-locus age prediction model (APM), allowing to obtain a Mean Absolute Deviation (MAD) between chronological and predicted ages of 5.35 years, explaining 94.1% of age variation. Validation approaches demonstrated the accuracy and reproducibility of the proposed multi-locus APM. Testing the APM in 51 blood samples from deceased individuals a MAD of 9.72 years was obtained. Potential differences in methylation status between samples from living and deceased individuals could exist since the highest age-correlated CpGs were different in some genes between both groups. In conclusion, our study using the bisulfite PCR sequencing method is in accordance with the high age prediction accuracy of DNA methylation levels in four previously reported age-associated genes. DNA methylation pattern differences between blood samples from living and deceased individuals should be taken into account in forensic contexts.


Assuntos
Envelhecimento/genética , Metilação de DNA/genética , Genética Forense/métodos , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Ilhas de CpG/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/sangue , Proteína de Domínio de Morte Associada a Edar/sangue , Elongases de Ácidos Graxos/sangue , Feminino , Humanos , Lactente , Proteínas com Homeodomínio LIM/sangue , Masculino , Pessoa de Meia-Idade , Proteínas Musculares/sangue , Reação em Cadeia da Polimerase , Fatores de Transcrição/sangue , Adulto Jovem
12.
Leg Med (Tokyo) ; 47: 101744, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32659707

RESUMO

In forensic investigation, retrieving biological information from DNA evidence is a promising field of interest. One of the applications is on the estimation of the age of the donor based on DNA methylation. A large number of studies focused on age prediction using the 450 K Human Methylation Beadchip. Various marker selection methods and prediction models have been considered. However, there is a lack of research evaluating different high-dimensional variable selection methods of CpG sites with various models for age prediction. The aim of this study is to evaluate four variable selection methods (forward selection, LASSO, elastic net and SCAD) combined with a classical statistical model and sophisticated machine learning models based on the mean absolute deviation (MAD) and the root-mean-square error (RMSE). We used publicly available 450 K data set containing 991 whole blood samples (age 19-101 years). We found that the multiple linear regression model with 16 markers selected from the forward selection method performed very well in age prediction (MAD = 3.76 years and RMSE = 5.01 years). On the other hand, the highly advanced ultrahigh dimensional variable selection methods and sophisticated machine learning algorithms appeared unnecessary for age prediction based on DNA methylation.


Assuntos
Envelhecimento/genética , Algoritmos , Ilhas de CpG/genética , Metilação de DNA , Aprendizado de Máquina , Modelos Estatísticos , Análise de Sequência de DNA/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Previsões , Genética Forense/métodos , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Leg Med (Tokyo) ; 47: 101737, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32580111

RESUMO

Genetic polymorphism of 17 autosomal short tandem repeat (STR) loci, included in the PowerPlex®18D amplification kit, were analyzed in Miao tribes from 58 different sampling microareas (N = 5255) of Guizhou as well as two cities (N = 151) of Hunan, China. Allele frequencies and forensic efficiency parameters were calculated. Moreover, comprehensive population genetic comparisons among 91 nationwide populations and 174 Asian populations were conducted based on raw genotype data and allele frequency data, respectively. Our results of forensic efficiency parameters showed that the panel was a robust tool in forensic individual identification and paternity cases for this population. Genetic affinities were observed among most of the Miao tribes revealed by multidimensional scaling plot, principal component analysis, and neighboring-joining tree. The genetic distance between Miao tribes and Han nationalities were varies by different geographical positions. Some of the Miao tribes were genetically closer to the Hmong-Mien populations living in southeastern contiguous regions and even the Indochina. The result coincided with the migration or reverse migration routes for Miao nationality in modern history. This study of the Miao tribes from plenty of microareas in Guizhou would be useful in reconstructing the population history and establishing a more comprehensive forensic reference database.


Assuntos
Grupos Étnicos/genética , Genética Forense/métodos , Variação Genética/genética , Genética Populacional , Repetições de Microssatélites/genética , Filogenia , Polimorfismo Genético , China/etnologia , Feminino , Frequência do Gene , Loci Gênicos/genética , Humanos , Masculino , Análise de Componente Principal
14.
Leg Med (Tokyo) ; 46: 101719, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32512465

RESUMO

In order to create an autosomal STR loci population database for Himachal Pradesh, 259 blood samples were taken from people residing in various regions of the state and AmpFlSTR® Identifiler® Plus PCR amplification kit was used for evaluation of 15 autosomal STR markers. A total of 149 alleles were investigated in this study with a mean allele number of 9.933 per locus. The locus D2S1338 was most informative in our data, as it had the highest discrimination power (PD-0.967) and the highest polymorphic information content (PIC-0.86). The matching probability and typical paternity index for all the studied loci were observed as 2.9x10-18 and 4.7x105, respectively. Discrimination power (CPD) and exclusion power (CPE) for all the studied loci were observed as 1 and 0.999998.


Assuntos
Impressões Digitais de DNA , Bases de Dados Genéticas , Genética Forense/métodos , Loci Gênicos/genética , Repetições de Microssatélites/genética , Alelos , Genômica , Humanos , Índia , Reação em Cadeia da Polimerase
15.
Mol Genet Genomics ; 295(5): 1263-1268, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32548728

RESUMO

In the routine of autosomal STR genotyping for forensic aims, tri-allelic patterns could be occasionally observed at a single locus in phenotypically normal individuals. Two predominant types of tri-allelic variants have been nominated. Uneven intensities of three alleles are normally considered as the Type 1 pattern, and balanced height of three alleles are considered as the Type 2 pattern. In this study, the prevalence of tri-allelic patterns at the CODIS STR loci was investigated in global populations based on previous reports. The frequencies of the Type 1 and Type 2 pattern manifest a correlation with the germline mutation rates at the CODIS STR loci. The irregular high frequencies of the Type 2 pattern at TPOX with low germline mutation rates could attribute to the stable inheritance of genomic rearrangement from ancestral origin. Furthermore, results from genetic pattern analysis show that only a single allele from STRs with the Type 1 pattern could be transmitted from parents to offsprings, while a single allele and a combination of two alleles from STRs with the Type 2 pattern present an equal opportunity of transmission from parents to offsprings. Altogether, these results provide a genetic portrait of STRs with tri-allelic patterns, which will help the genetic interpretation of tri-allelic patterns in forensic practice.


Assuntos
Genética Forense/métodos , Mutação em Linhagem Germinativa , Repetições de Microssatélites , China , Loci Gênicos , Humanos , Masculino , Paternidade , Prevalência
16.
Leg Med (Tokyo) ; 47: 101727, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32562959

RESUMO

DNA profiling can identify an individual from a sample of biological material but it does not reveal what body fluid or tissue source the DNA profile originated from. In many cases it is important to know from what body fluid or tissue the DNA profile originated in order to provide crucial information necessary to the investigation, especially in cases where the victims are not able to give information about the dynamics of the event. For this purpose messenger RNA (mRNA) analysis has been shown to be a suitable method for the identification of body fluids, resulting in a trend to overcome the conventional approaches. Here we present the first report about case regarding a three-year-old child supposedly victim of a sexual assault with digital penetration. Thanks to the use of the combined DNA profiling and RNA analysis it was possible to demonstrate the sexual assault suffered by the victim.


Assuntos
Abuso Sexual na Infância , Vítimas de Crime , Impressões Digitais de DNA/métodos , Genética Forense/métodos , RNA Mensageiro/análise , Pré-Escolar , Feminino , Humanos , Unhas
17.
Rev. esp. med. legal ; 46(2): 75-80, abr.-jun. 2020. graf
Artigo em Espanhol | IBECS | ID: ibc-193994

RESUMO

En los últimos años la genética ha adquirido una gran importancia en los procesos de identificación masiva de víctimas y constituye, en muchos casos, la única herramienta útil. Algunas instituciones externalizan estos análisis en laboratorios especializados. Es el caso de la Unidad de Derechos Humanos del Servicio Médico Legal (SML) de Chile, creada con el objetivo de identificar y restituir a las familias los restos de las víctimas de la dictadura cívico-militar instaurada en el país entre 1973 y 1990, que provocó más de 1.300 desaparecidos y muertos sin entrega. La externalización de los análisis impone la necesidad de establecer una rigurosa sistemática de revisión y control de calidad de los análisis realizados por el laboratorio externo, lo que incluye asegurar la trazabilidad de las muestras y los análisis, además de reproducir tanto la comparación de los perfiles genéticos como su valoración estadística. En este trabajo se presenta la experiencia del SML en esta materia y se establecen una serie de recomendaciones que pueden ser utilizadas como guía por otras instituciones que decidan externalizar los análisis genéticos en procesos de identificación masiva de víctimas


In recent years, genetics has acquired great importance in the processes of mass victim identification and, in many cases, is the only useful tool. Some institutions outsource these analyses to specialized laboratories. This is the case of the Human Rights Unit of the Legal Medical Service (SML) of Chile, created with the objective of identifying and restoring to families the remains of the victims of the civic-military dictatorship established in the country between 1973 and 1990, which caused more than 1,300 missing and dead without delivery. The outsourcing of the analyses imposes the need to establish a rigorous systematic review and quality control of the analyses performed by the external laboratory, which includes ensuring traceability of the samples and analyses, in addition to reproducing the comparison of the genetic profiles and their statistical assessment. This paper presents the experience of the SML in this area and establishes a series of recommendations that can be used as a guide by other institutions that decide to outsource genetic analysis in processes of mass identification of victims


Assuntos
Humanos , Testes Genéticos/métodos , Bases de Dados de Ácidos Nucleicos/organização & administração , Identificação de Vítimas , Genética Forense/métodos , Gestão da Qualidade Total/métodos , Chile/epidemiologia , Direitos Humanos/legislação & jurisprudência , Antropologia Forense/métodos , Controle de Qualidade , Padrões de Referência
18.
Mol Genet Genomics ; 295(4): 1027-1038, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32206883

RESUMO

When traditional short tandem repeat profiling fails to provide valuable information to arrest the criminal, forensic ancestry inference of the biological samples left at the crime scene will probably offer investigative leads and facilitate the investigation process of the case. That is why there are consistent efforts in developing panels for ancestry inference in forensic science. Presently, a 30-plex next generation sequencing-based assay was exploited in this study by assembling well-differentiated single nucleotide polymorphisms for ancestry assignment of unknown individuals from three continental populations (African, European and East Asian). And meanwhile, relatively balanced population-specific differentiation values were maintained to avoid the over-estimation or under-estimation of co-ancestry proportions in individuals with admixed ancestry. The principal component analysis and STRUCTURE analysis of reference populations, test populations and the studied Mongolian group indicated that the novel assay was efficient enough to determine the ancestry origin of an unknown individual from the three continental populations. Besides, ancestry membership proportion estimations for the Mongolian group revealed that a large fraction of the ancestry was contributed by East Asian genetic component (approximately 83.9%), followed by European (approximately 12.6%) and African genetic components (approximately 3.5%), respectively. And next generation sequencing technology applied in this study offers possibility to incorporate more single nucleotide polymorphisms for individual identification and phenotype prediction into the same assay to provide as many as possible investigative clues in the future.


Assuntos
Antropologia Forense/métodos , Genética Forense/métodos , Genética Populacional , Sequenciamento de Nucleotídeos em Larga Escala , Grupo com Ancestrais do Continente Africano/genética , Grupo com Ancestrais do Continente Asiático/genética , Grupos de Populações Continentais/genética , Grupo com Ancestrais do Continente Europeu/genética , Extremo Oriente/epidemiologia , Genótipo , Humanos , Repetições de Microssatélites/genética , Polimorfismo de Nucleotídeo Único/genética
19.
Forensic Sci Rev ; 32(1): 23-54, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32007927

RESUMO

Advancements in DNA sequencing technologies are occurring at a rapid rate. Various platforms have proven useful in all aspects of health and science research, from molecular diagnostics in cancer research to spore identification in bioterrorism. In the field of forensics, one particular single-molecule sequencing platform shows promise for becoming a viable solution for small to midsize forensic laboratories. Oxford Nanopore Technologies (ONT) has developed a portable, nanopore-based sequencing instrument that has already been utilized for on-site identification of Zika and Ebola viruses, full genome sequencing, evaluation of DNA and RNA base modifications, and enrichment-free mitochondrial DNA analysis. The rapid development of this technology creates possibilities relevant to standard DNA sequencing, direct analysis of forensic samples, including blood, semen, and buccal swabs, mitochondrial DNA analysis, SNP and STR analysis, familial identification, and microbial identification for bioterrorism and geolocation. The small size of the platform, its low cost, and its requirement of only basic laboratory equipment makes this platform well suited for small laboratories wishing to begin developing expertise in sequence-based forensic analyses. Herein, we outline recent developments and applications of nanopore sequencing technologies and their potential application in forensic analysis. We address current and potential techniques in mitochondrial DNA analysis, SNP and STR typing, and microbial identification. Additionally, we discuss recent developments in library preparation and data analysis tool further streamlining the sequencing process that integrate workflows in laboratories or in remote field scenarios.


Assuntos
Genética Forense/métodos , Sequenciamento por Nanoporos , Humanos
20.
Int J Legal Med ; 134(2): 461-471, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31897668

RESUMO

Bones are often found in mass grave crime scene. To increase DNA identification success rates, a highly efficient DNA extraction method should be selected. Several DNA extraction methods for human bones have been published yet never been systematically compared, and some are time-consuming or complex. As such, a quick and highly efficient DNA extraction method was developed and compared with three published methods (Hi-Flow silica-based, total demineralization (TD) and PrepFiler BTA) using 70 fresh and 22 casework bones from different body parts. The highest median DNA concentrations were obtained from developed method (135.85 ng/µL and 0.224 ng/µL for fresh and casework bones, respectively). For residual PCR inhibitors, the threshold cycle (Ct) of the internal positive control (IPC) showed that developed method and PrepFiler BTA removed most PCR inhibitors. Similarly, 95.45% of casework STR profiles obtained using the developed protocol meet the standard requirements for Australian National Criminal Investigative DNA Database (NCIDD) entry, followed by 86.35% using TD, 81.82% using PrepFiler BTA, and 45.45% using Hi-Flow. Additionally, DNA extracts from seven different bones revealed that the 1st distal phalange of the hand contained the highest DNA concentration of 338.43 ng/µL, which was three times higher than the tibia and femur. Our findings suggest that developed method was highly efficient for casework bone analysis. It significantly reduced the extraction processing time down to 4 h and is two to four times cheaper compared with other methods. In practice, both the extraction method and the bone sampling must be considered by a forensic DNA analyst to increase the chances of successful identification.


Assuntos
Osso e Ossos/química , Impressões Digitais de DNA/métodos , DNA/isolamento & purificação , Genética Forense/métodos , Repetições de Microssatélites , Densidade Óssea , Fêmur/química , Falanges dos Dedos da Mão/química , Humanos , Tíbia/química
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