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1.
Int J Legal Med ; 135(4): 1359-1367, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33907868

RESUMEN

Most of insertion/deletion polymorphisms are diallelic molecular markers characterized as small amplicon sizes, high inter-population diversities, and low mutation rates, which make them the promising genetic markers in biogeographic ancestor inference field. The developmental validations of a 39 ancestry informative marker-insertion/deletion (AIM-InDel) panel and the genetic polymorphic investigations of this panel were performed in the Shaanxi Han population of China. The developmental validation included the optimizations of PCR-related indicators, repeatability, reproducibility, precision, accuracy, sensitivity, species specificity, stability of the panel, and the abilities in analyzing degraded, casework, and mixture samples, and the present results demonstrated that this 39 AIM-InDel panel was robust, sensitive, and accurate. For the population diversity analyses, the combined discrimination power value of 38 AIM-InDel loci except for rs36038238 locus was 0.999999999931257, indicating that this novel panel was highly polymorphic, biogeographic informative, and could be also used in individual identifications in the Shaanxi Han population.


Asunto(s)
Pueblo Asiatico/genética , Genética Forense/instrumentación , Análisis de Secuencia de ADN/métodos , China/etnología , Marcadores Genéticos , Humanos , Mutación INDEL , Linaje , Polimorfismo Genético , Reproducibilidad de los Resultados , Especificidad de la Especie
2.
Forensic Sci Med Pathol ; 17(2): 199-207, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33180274

RESUMEN

PURPOSE: We investigated the recovery and extraction efficiency of DNA from three metal surfaces (brass, copper, steel) relevant to forensic casework, and plastic (control) using two different swabbing systems; Rayon and Isohelix™ swabs, with sterile water and isopropyl alcohol respectively, as the wetting solutions. METHODS: Twenty nanograms of human genomic DNA were applied directly to Isohelix™ and Rayon swabs; and to the metal and plastic substrates. All substrates were left to dry for 24 h, followed by single wet swabbing and extraction with the DNA IQ™ System. DNA extracts were quantified using real time quantitative PCR assays with SYBR green chemistry. RESULTS: DNA was extracted from directly seeded Isohelix™ swabs with a high efficiency of 98%, indicating effective DNA-release from the swab into the extraction buffer. In contrast, only 58% of input DNA was recovered from seeded Rayon swabs, indicating higher DNA retention by these swabs. Isohelix™ swabs recovered 32 - 53% of DNA from metal surfaces, whilst the Rayon swabs recovered 11-29%. DNA recovery was lowest from copper and highest from brass. Interestingly, Rayon swabs appeared to collect more DNA from the plastic surface than Isohelix™ swabs, however, due to the lower release of DNA from Rayon swabs they returned less DNA overall following extraction than Isohelix™ swabs. CONCLUSION: These results demonstrate that DNA samples deposited on metal surfaces can be more efficiently recovered using Isohelix™ swabs wetted with isopropyl alcohol than Rayon swabs wetted with sterile water, although recovery is affected by the substrate type.


Asunto(s)
Celulosa , Genética Forense , Manejo de Especímenes , Celulosa/química , ADN/análisis , Genética Forense/instrumentación , Genética Forense/métodos , Manejo de Especímenes/instrumentación , Manejo de Especímenes/normas
3.
Int J Legal Med ; 133(3): 751-757, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30460509

RESUMEN

The identification of the cellular origin and composition of crime scene-related traces can provide crucial insight into a crime scene reconstruction. In the last decade, especially mRNA-based body fluid and tissue identification (BFI) has been vigorously examined. Besides capillary electrophoretic (CE) and real-time quantitative PCR (RT-qPCR)-based approaches for mRNA detection, melt curve analysis bears potential as a simple-to-use method for BFI. The ParaDNA® Body Fluid ID Test relies on HyBeacon® probes and was developed as a rapid test for mRNA-based BFI of six different body fluids: vaginal fluid, seminal fluid, sperm cells, saliva, menstrual, and peripheral blood. The herein presented work was performed as an "acid test" of the system and should clarify whether the approach matches the requirements of forensic routine casework in German police departments. Tested samples consisted of single source as well as of mixed samples.


Asunto(s)
Análisis Químico de la Sangre , Moco del Cuello Uterino/química , Genética Forense/instrumentación , ARN Mensajero/metabolismo , Saliva/química , Semen/química , Femenino , Genética Forense/métodos , Marcadores Genéticos , Humanos , Masculino , Menstruación , ARN Mensajero/genética , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Temperatura de Transición
4.
Int J Legal Med ; 133(6): 1641-1650, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30687898

RESUMEN

The scope of forensic kinship analysis is being extended to more distant or complex relationships. However, current methods and standards in this field do not meet the needs of casework. The next-generation sequencing (NGS) technology may hold an advantage in this field to traditional methods due to its strong power to get much more genetic information. To evaluate the effectiveness of NGS to identify the 2nd-degree kinship pairs, DNA samples of 227 individuals from 49 Hebei Han pedigrees were tested by Goldeneye™ 20A kit using capillary electrophoresis (CE) to confirm the relationships within each pedigree, and those of 111 individuals within 97 confirmed grandparent-grandchild or avuncular pairs were analyzed by ForenSeq™ DNA Signature Prep Kit using MiSeq® FGx™ DNA sequencing platform. We calculated the likelihood ratio (LR) based on ITO method and the identical by state (IBS) score of 97 kinship pairs and compared with those of 97 unrelated pairs. According to the results summarized and analyzed by Fisher discriminant analysis and leave-one-out cross-validation (LOOCV) method, ITO method showed higher accuracy than IBS method, even with less information. Therefore, we proposed a recommendation of the thresholds for pairwise 2nd-degree kinship identification for Hebei Han population based on ITO method. When using ITO method based on 94 SNPs and the length information of 27 autosomal STRs, cumulative likelihood ratio (CLR) > 1 and CLR < 0.1 are recommended as the thresholds of confirming and excluding, respectively. The accuracy applying such thresholds is greater than 95%, indicating the promising application value of NGS in this field and providing a direction for further kinship identification strategy selection. Further studies are needed to get the population genetic data of loci contained in the kit based on all sequence information including flanking regions to make full use of the NGS data to improve the accuracy of kinship analysis.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento/instrumentación , Linaje , Análisis de Secuencia de ADN , Programas Informáticos , China , Dermatoglifia del ADN , Análisis Discriminante , Etnicidad/genética , Genética Forense/instrumentación , Genética Forense/métodos , Marcadores Genéticos , Genotipo , Humanos , Funciones de Verosimilitud , Repeticiones de Microsatélite , Polimorfismo de Nucleótido Simple
5.
Sci Justice ; 59(1): 20-28, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30654965

RESUMEN

In recent years, jurisdictions across the United States have expressed a growing interest in aiding criminal investigations through the use of familial DNA searching (FDS)- a forensic technique to identify family members through DNA databases. The National Survey of CODIS Laboratories surveyed U.S. CODIS laboratories about their perceptions, policies, and practices related to FDS. In total, 103 crime labs completed the survey (77% response rate). Labs in 11 states reported using FDS, while labs in 24 states reported using a similar-but distinct- practice of partial matching. Although the majority of labs had positive perceptions about the ability of FDS to assist investigations, labs also reported a number of concerns and challenges with implementing FDS. Respondents reported using either practice a limited amount with modest numbers of convictions resulting from both FDS and partial matching. The article reports on varying practices related to official policies, training, eligibility, the software search, lineage testing, requirements for releasing information, and subsequent investigative work. Finally, the article discusses what can be learned from this survey, accompanying limitations, and implications for decision-makers considering using FDS.


Asunto(s)
Dermatoglifia del ADN/métodos , ADN/genética , Bases de Datos de Ácidos Nucleicos/instrumentación , Genética Forense/instrumentación , Laboratorios , Encuestas y Cuestionarios , Costos y Análisis de Costo , Familia , Humanos , Aplicación de la Ley/métodos , Políticas , Programas Informáticos/clasificación , Programas Informáticos/estadística & datos numéricos , Estados Unidos
6.
Fa Yi Xue Za Zhi ; 34(2): 161-164, 2018 04.
Artículo en Zh | MEDLINE | ID: mdl-29923383

RESUMEN

OBJECTIVES: To validate the analysis capability of RapidHIT™ 200 system for four kinds of routine forensic samples and the recyclable capability of template, template DNA and PCR products in the process of twice duplicate detection. METHODS: The buccal swabs underwent the test twice by RapidHIT™ 200 system, and the template DNA and PCR products that arose in the system were also tested for two times. After four kinds of routine forensic samples were detected by RapidHIT™ 200 system, the follow-up tests of the template, template DNA and PCR products that arose in the system were performed. RESULTS: The STR loci could be detected in the buccal swabs by the system for the first time. However, part of the STR loci lost during the second test. And the peak value obtained in the second test was significantly reduced than the one in the first time. The average STR loci detection rates of the template DNA and PCR products were both less than 50% in the second test, which were significantly reduced than that in the first test. In addition, the analysis capability of the system for the tissues and buccal swabs was better than that for the blood and cigarette butts. Compared with the first test, the STR loci detection rate of the tested items, template DNA and PCR products decreased with the numbers of tests. CONCLUSIONS: RapidHIT™ 200 system is more effective in retesting buccal swabs than other samples, whereas the items, DNA template, PCR products obtained in the first and second time cannot be directly used for the further application and study of forensic medicine.


Asunto(s)
Automatización , Genética Forense/instrumentación , Repeticiones de Microsatélite/genética , Moldes Genéticos , Genética Forense/métodos , Medicina Legal , Humanos , Mucosa Bucal/química , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
7.
Ann Hum Biol ; 44(7): 581-592, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28948844

RESUMEN

CONTEXT: Over the last few decades, advances in sequencing have improved greatly. One of the most important achievements of Next Generation Sequencing (NGS) is to produce millions of sequence reads in a short period of time, and to produce large sequences of DNA in fragments of any size. Libraries can be generated from whole genomes or any DNA or RNA region of interest without the need to know its sequence beforehand. This allows for looking for variations and facilitating genetic identification. OBJECTIVES: A deep analysis of current NGS technologies and their application, especially in forensics, including a discussion about the pros and cons of these technologies in genetic identification. METHODS: A systematic literature search in PubMed, Science Direct and Scopus electronic databases was performed for the period of December 2012 to June 2015. RESULTS: In the forensic field, one of the main problems is the limited amount of sample available, as well as its degraded state. If the amount of DNA input required for preparing NGS libraries continues to decrease, nearly any sample could be sequenced; therefore, the maximum information from any biological remains could be obtained. Additionally, microbiome typification could be an interesting application to study for crime scene characterisation. CONCLUSIONS: NGS technologies are going to be crucial for DNA human typing in cases like mass disasters or other events where forensic specimens and samples are compromised and degraded. With the use of NGS it will be possible to achieve the simultaneous analysis of the standard autosomal DNA (STRs and SNPs), mitochondrial DNA, and X and Y chromosomal markers.


Asunto(s)
Genética Forense/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Genética Forense/instrumentación , Humanos
8.
Genet Mol Res ; 15(1)2016 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-26909950

RESUMEN

Currently, the widely used automated capillary electrophoresis-based short tandem repeat (STR) genotyping method for genetic screening in forensic practice is laborious, time-consuming, expensive, and technically challenging in some cases. Thus, new molecular-based strategies for conclusively identifying forensically relevant biological evidence are required. Here, we used high-resolution melting analysis (HRM) for Y-chromosome STR genotyping for forensic genetic screening. The reproducibility of the melting profile over dilution, sensitivity, discrimination power, and other factors was preliminarily studied in 10 Y-STR loci. The results showed that HRM-based approaches revealed more genotypes (compared to capillary electrophoresis), showed higher uniformity in replicate tests and diluted samples, and enabled successful detection of DNA at concentrations as low as 0.25 ng. For mixed samples, the melting curve profiles discriminated between mixed samples based on reference samples with high efficiency. The triplex Y-chromosome STR HRM assay was performed and provided a foundation for further studies such as a multiplex HRM assay. The HRM approach is a one-step application and the entire procedure can be completed within 2 h at a low cost. In conclusion, our findings demonstrate that the HRM-based Y-STR assay is a useful screening tool that can be used in forensic practice.


Asunto(s)
Cromosomas Humanos Y/química , ADN/genética , Genética Forense/métodos , Técnicas de Genotipaje , Repeticiones de Microsatélite , Dermatoglifia del ADN , Cartilla de ADN/química , Electroforesis Capilar , Genética Forense/instrumentación , Sitios Genéticos , Pruebas Genéticas , Genotipo , Humanos , Desnaturalización de Ácido Nucleico , Reproducibilidad de los Resultados
9.
Int J Legal Med ; 127(6): 1079-86, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23736940

RESUMEN

The Ion AmpliSeq™ HID single nucleotide polymorphism (SNP) panel, a primer pool of 103 autosomal SNPs and 33 Y-SNPs, was evaluated using the Ion 314™ Chip on the Ion PGM™ Sequencer with four DNA samples. The study focused on the sequencing of DNA at three different initial target quantities, related interpretation issues, and concordance of results with another sequencing platform, i.e., Genome Analyzer IIx. With 10 ng of template DNA, all genotypes at the 136 SNPs were detected. With 1 ng of DNA, all SNPs were detected and one SNP locus in one sample showed extreme heterozygote imbalance on allele coverage. With 100 pg of DNA, an average of 1.6 SNP loci were not detected, and an average of 4.3 SNPs showed heterozygote imbalance. The average sequence coverage was 945-600× at autosomal SNPs and 465-209× at Y-SNPs for 10 ng-100 pg of DNA. The average heterozygote allele coverage ratio was 89.6-61.8 % for 10 ng-100 pg of DNA. At 10 ng of DNA, all genotypes of the 95 SNPs shared between the two different sequencing platforms were concordant except for one SNP, rs1029047. The error was due to the misalignment of a flanking homopolymer. Overall, the data support that genotyping a large battery of SNPs is feasible with massively parallel sequencing. With barcode systems, better allele balance, and specifically designed alignment software, a more comprehensive rapid genotyping and more cost-effective results may be obtained from multiple samples in one analysis than are possible with current typing and capillary electrophoresis systems.


Asunto(s)
ADN/genética , Genética Forense/métodos , Genotipo , Polimorfismo de Nucleótido Simple/genética , Análisis de Secuencia de ADN , Alelos , Estudios de Factibilidad , Femenino , Genética Forense/instrumentación , Amplificación de Genes , Biblioteca de Genes , Tamización de Portadores Genéticos , Sitios Genéticos/genética , Humanos , Masculino , Sensibilidad y Especificidad , Análisis de Secuencia de ADN/instrumentación
10.
Int J Legal Med ; 127(2): 299-308, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22895803

RESUMEN

The detection of semen can assist in reconstructing the events of a sexual assault and impact the outcome of legal dispositions. Many methods currently are used for detecting the presence of semen, but they all have limitations with regards to specificity, sample degradation/consumption, stability of biomolecule assayed, and/or incompatibility with downstream individual identification assays. DNA is routinely collected at sexual assault crime scenes and is widely used for individual identification. The DNA also carries methylation patterns that are tissue specific. To date, however, assays designed to exploit methylation patterns suffer from complex chemistries and unwieldy analyses. DSI-Semen™ kit uses a novel approach involving CpG methylation-sensitive restriction endonuclease digestion coupled to a multiplexed polymerase chain reaction (PCR) to generate an amplicon profile that makes it possible to determine whether the tissue source of a DNA sample was semen or non-semen. The assay returned an appropriate positive result for semen with neat semen, semen stains, and semen/non-semen tissue mixtures. The assay is robust and reliable, with a positive result for semen given as little as 31 pg of template DNA input. Low levels of semen were detected in mixtures of semen and other body fluids. UV-exposed samples and those in the presence of limited concentrations of known PCR inhibitors were typeable. The DSI-Semen™ kit provides a reliable tool for the determination of DNA being derived from semen.


Asunto(s)
Metilación de ADN , Enzimas de Restricción del ADN/metabolismo , Genética Forense/instrumentación , Semen/metabolismo , Animales , Análisis Químico de la Sangre , ADN/efectos de los fármacos , Degradación Necrótica del ADN , Dermatoglifia del ADN , Fragmentación del ADN , Cartilla de ADN , Electroforesis , Humanos , Funciones de Verosimilitud , Límite de Detección , Masculino , Repeticiones de Microsatélite , Mucosa Bucal/metabolismo , Reacción en Cadena de la Polimerasa Multiplex , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados , Saliva/metabolismo , Programas Informáticos , Rayos Ultravioleta
11.
Am J Forensic Med Pathol ; 33(4): 322-7, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22835962

RESUMEN

To resolve cases involving unidentified cadavers, the study of polymorphic DNA markers of old bones is an invaluable but often challenging tool used in forensic genetics. Some of the difficulties encountered involve the limited quantity of endogenous DNA, its subsequent degradation (a result of elapsed time, environmental conditions, and the microorganisms that develop during the postmortem phase), and the coextraction of substances that inhibit amplification reactions. For these reasons, it is necessary to direct research toward the development of new extraction techniques with the goal of obtaining adequate quantities of high-quality DNA.The aim of this study was to improve the collection of extracted DNA compared with the amount of DNA obtained with the NucleoSpin DNA Trace Kit (Macherey Nagel) protocol for the extraction of genomic DNA from human bones. A modified version of the standard protocol is presented.The modified method for the extraction of genomic DNA, followed by amplification reaction, allowed for identification of 4 cadavers and typification of 1 cadaver. The study carried out involved unidentified cadavers, or their remains, discovered after a long period from time of death.


Asunto(s)
ADN/aislamiento & purificación , Fémur/química , Genética Forense/métodos , Adolescente , Adulto , Determinación de la Edad por el Esqueleto , Entierro , Dermatoglifia del ADN , Electroforesis Capilar , Femenino , Antropología Forense , Genética Forense/instrumentación , Humanos , Masculino , Persona de Mediana Edad , Momias , Reacción en Cadena de la Polimerasa , Cambios Post Mortem , Determinación del Sexo por el Esqueleto , Diente/química , Adulto Joven
12.
Arch Kriminol ; 230(5-6): 166-76, 2012.
Artículo en Alemán | MEDLINE | ID: mdl-23367791

RESUMEN

For complete and conclusive DNA profiling a sufficient amount of DNA must be available. For that, biological traces are recovered from crime scenes using special trace recovery material. The current method to collect biological traces for DNA analysis is to wipe them off with cotton swabs. However, for a few years the use of adhesive tapes has also been described for the recovery of evidence. In 2009, an adhesive tape was launched which was specially developed for the collection of biological traces. This product called Scenesafe FAST Tape (SSF) was investigated in this work to give recommendations for its use in evidence recovery. The results of this work show that the DNA can be extracted from the SSF very well. However, the tapes seem less suitable for direct use at the crime scene, as they are not flexible enough for adaptation to different crime scene conditions and the risk of contamination is higher than when collecting evidence with cotton swabs. Neither SSF nor cotton swabs are optimal for all requirements. The best method to recover biological evidence is still dependent on the surface material and the circumstances at the crime scene.


Asunto(s)
Recolección de Muestras de Sangre/instrumentación , Dermatoglifia del ADN/instrumentación , ADN/análisis , ADN/genética , Genética Forense/instrumentación , Cinta Quirúrgica , Recolección de Muestras de Sangre/métodos , Diseño de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
13.
Sud Med Ekspert ; 55(5): 34-7, 2012.
Artículo en Ruso | MEDLINE | ID: mdl-23272562

RESUMEN

The present study was designed to estimate the possibilities of application of the laser capture microdissection (LCM) technology for the molecular-genetic expert analysis (genotyping) of human chromosomal DNA. The experimental method employed for the purpose was the multiplex multilocus analysis of autosomal DNA polymorphism in the preparations of buccal epitheliocytes obtained by LCM. The key principles of the study were the application of physical methods for contrast enhancement of the micropreparations (such as phase-contrast microscopy and dark-field microscopy) and PCR-compatible cell lysis. Genotyping was carried out with the use of AmpFISTR Minifiler TM PCR Amplification Kits ("Applied Biosynthesis", USA). It was shown that the technique employed in the present study ensures reliable genotyping of human chromosomal DNA in the pooled preparations containing 10-20 dissected diploid cells each. This result fairly well agrees with the calculated sensitivity of the method. A few practical recommendations are offered.


Asunto(s)
Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/métodos , Identificación Biométrica/métodos , Cromosomas Humanos/genética , ADN/genética , Genética Forense/métodos , Técnicas de Genotipaje/métodos , Captura por Microdisección con Láser/métodos , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados/instrumentación , Identificación Biométrica/instrumentación , ADN/aislamiento & purificación , Células Epiteliales , Genética Forense/instrumentación , Técnicas de Genotipaje/instrumentación , Humanos , Captura por Microdisección con Láser/instrumentación , Mucosa Bucal/citología
14.
Int J Legal Med ; 125(5): 629-36, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20552217

RESUMEN

Because of their sensitivity and high level of discrimination, short tandem repeat (STR) maker systems are currently the method of choice in routine forensic casework and data banking, usually in multiplexes up to 15-17 loci. Constraints related to sample amount and quality, frequently encountered in forensic casework, will not allow to change this picture in the near future, notwithstanding the technological developments. In this study, we present a free online calculator named PopAffiliator ( http://cracs.fc.up.pt/popaffiliator ) for individual population affiliation in the three main population groups, Eurasian, East Asian and sub-Saharan African, based on genotype profiles for the common set of STRs used in forensics. This calculator performs affiliation based on a model constructed using machine learning techniques. The model was constructed using a data set of approximately fifteen thousand individuals collected for this work. The accuracy of individual population affiliation is approximately 86%, showing that the common set of STRs routinely used in forensics provide a considerable amount of information for population assignment, in addition to being excellent for individual identification.


Asunto(s)
Computadores/legislación & jurisprudencia , Genética Forense/instrumentación , Genética Forense/legislación & jurisprudencia , Marcadores Genéticos/genética , Genética de Población/legislación & jurisprudencia , Genotipo , Repeticiones de Microsatélite/genética , Grupos de Población/genética , Inteligencia Artificial , Frecuencia de los Genes/genética , Humanos
15.
Croat Med J ; 52(3): 299-313, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21674826

RESUMEN

AIM: To use parallel array pyrosequencing to deconvolute mixtures of mitochondrial DNA (mtDNA) sequence and provide high resolution analysis of mtDNA heteroplasmy. METHODS: The hypervariable segment 1 (HV1) of the mtDNA control region was analyzed from 30 individuals using the 454 GS Junior instrument. Mock mixtures were used to evaluate the system's ability to deconvolute mixtures and to reliably detect heteroplasmy, including heteroplasmic differences between 5 family members of the same maternal lineage. Amplicon sequencing was performed on polymerase chain reaction (PCR) products generated with primers that included multiplex identifiers (MID) and adaptors for pyrosequencing. Data analysis was performed using NextGENe® software. The analysis of an autosomal short tandem repeat (STR) locus (D18S51) and a Y-STR locus (DYS389 I/II) was performed simultaneously with a portion of HV1 to illustrate that multiplexing can encompass different markers of forensic interest. RESULTS: Mixtures, including heteroplasmic variants, can be detected routinely down to a component ratio of 1:250 (20 minor variant copies with a coverage rate of 5000 sequences) and can be readily detected down to 1:1000 (0.1%) with expanded coverage. Amplicon sequences from D18S51, DYS389 I/II, and the second half of HV1 were successfully partitioned and analyzed. CONCLUSIONS: The ability to routinely deconvolute mtDNA mixtures down to a level of 1:250 allows for high resolution analysis of mtDNA heteroplasmy, and for differentiation of individuals from the same maternal lineage. The pyrosequencing approach results in poor resolution of homopolymeric sequences, and PCR/sequencing artifacts require a filtering mechanism similar to that for STR stutter and spectral bleed through. In addition, chimeric sequences from jumping PCR must be addressed to make the method operational.


Asunto(s)
ADN Mitocondrial/genética , Genética Forense/métodos , Amplificación de Genes/genética , Repeticiones de Microsatélite/genética , Interpretación Estadística de Datos , Estudios de Factibilidad , Femenino , Genética Forense/instrumentación , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN
16.
Croat Med J ; 52(3): 368-71, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21674833

RESUMEN

AIM: To investigate allele distribution and genetic parameters of a population-based sample from Maghreb region. METHODS: Allele frequencies for 5 new autosomal short tandem repeat (STR) markers (D10S1248, D22S1045, D2S441, D1S1656, and D12S391) and several forensic parameters were determined for 95 unrelated individuals. RESULTS: The combined power of discrimination and power of exclusion for the 5 loci were high (0.9999991 and 0.9954757, respectively). Allele frequencies were compared with previously published population data. Significant differences were found between Maghreb population and all other populations at the locus D2S441. Also, significant differences were found between the Maghreb and the African American population at the D22S1045, D1S1656, and D12S391 loci, between Maghreb and Caucasian population at the D1S1656 locus, and between Maghreb and Hispanic population at the D22S1045 locus. CONCLUSIONS: Typing of the 5 new STR loci may provide a useful addition to the previously established sets of autosomal STRs.


Asunto(s)
Alelos , Genética Forense/métodos , Marcadores Genéticos/genética , Variación Genética/genética , Repeticiones de Microsatélite/genética , Población Blanca/genética , Bases de Datos Genéticas , Genética Forense/instrumentación , Amplificación de Genes , Frecuencia de los Genes , Genética de Población , Humanos , Italia
17.
Croat Med J ; 52(3): 336-43, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21674829

RESUMEN

AIM: To perform a genetic characterization of 7 skeletons from medieval age found in a burial site in the Aragonese Pyrenees. METHODS: Allele frequencies of autosomal short tandem repeats (STR) loci were determined by 3 different STR systems. Mitochondrial DNA (mtDNA) and Y-chromosome haplogroups were determined by sequencing of the hypervariable segment 1 of mtDNA and typing of phylogenetic Y chromosome single nucleotide polymorphisms (Y-SNP) markers, respectively. Possible familial relationships were also investigated. RESULTS: Complete or partial STR profiles were obtained in 3 of the 7 samples. Mitochondrial DNA haplogroup was determined in 6 samples, with 5 of them corresponding to the haplogroup H and 1 to the haplogroup U5a. Y-chromosome haplogroup was determined in 2 samples, corresponding to the haplogroup R. In one of them, the sub-branch R1b1b2 was determined. mtDNA sequences indicated that some of the individuals could be maternally related, while STR profiles indicated no direct family relationships. CONCLUSIONS: Despite the antiquity of the samples and great difficulty that genetic analyses entail, the combined use of autosomal STR markers, Y-chromosome informative SNPs, and mtDNA sequences allowed us to genotype a group of skeletons from the medieval age.


Asunto(s)
Huesos , Cementerios/historia , Cromosomas Humanos Y/genética , ADN Mitocondrial/análisis , Genética Forense/métodos , Repeticiones de Microsatélite/genética , Factores de Edad , ADN Mitocondrial/genética , Europa (Continente) , Genética Forense/instrumentación , Amplificación de Genes , Haplotipos , Historia Medieval , Humanos , Masculino , Filogenia , España
18.
Arch Med Sadowej Kryminol ; 61(2): 153-60, 2011.
Artículo en Polaco | MEDLINE | ID: mdl-22390129

RESUMEN

The newly designed and optimized miniplex contains the following markers: D3S3053, D6S474, D9S2157, D20S482 and sex-determining marker - amelogenin. The target amplicon lengths for the developed multiplex are 71-135 bp. Amplification products were detected in a fluorescence based automated genetic analyzer. A minimal DNA sample required to obtain full genetic profiles was 250 pg. The usefulness of these miniSTRs in genotyping of severely degraded forensic samples, such as stains of blood and semen, saliva on cigarette butts and telogen hair has been confirmed in validation studies. The designed pentaplex offers a new potential screening tool in cases of old crime scenes, mass disasters, mass graves, etc., where DNA degradation, body fragmentation or large numbers of victims occur. The use of additional non-CODIS markers may increase typeability of severely degraded samples and ensure a higher potential for genetic discrimination.


Asunto(s)
Dermatoglifia del ADN/instrumentación , Dermatoglifia del ADN/normas , Cartilla de ADN/análisis , Genética Forense/instrumentación , Frecuencia de los Genes , Polimorfismo de Nucleótido Simple/genética , Análisis de Secuencia de ADN/métodos , Amelogenina/genética , Genética Forense/métodos , Genética Forense/normas , Genotipo , Humanos
19.
Forensic Sci Int Genet ; 53: 102533, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34058534

RESUMEN

In anticipation of offering phenotypic and biogeographical ancestry predictions to help resolve cases, the Verogen ForenSeq™ DNA Signature Prep kit/Primer Mix B was evaluated in the context of Micro MiSeq® Flow Cells. These flow cells were determined as the best format for a quick turnaround time response and cost effective approach compared to standard flow cells. The phenotype informative SNPs (piSNPs) and ancestry informative SNPs (aiSNPs) were thoroughly examined through sensitivity, reproducibility and repeatability, concordance, robustness (mock casework) and low level DNA mixture studies purposely selecting individuals with different phenotypes (hair and eye color) when possible and different biogeographical ancestry. SNP locus-specific interpretation thresholds were established for the Universal Analysis Software (UAS) based on surviving alleles and SNP predictor rank to minimize false homozygous genotypes and maximize the information that can be derived from an unknown sample. Dropin alleles' intensity determined an appropriate threshold to minimize false heterozygous SNP genotypes. The selection of inappropriate interpretation thresholds was shown to have major consequences on phenotypic predictions. A 3.2% and 4.8% minor DNA component contribution to a DNA mixture had no impact on ancestry predictions whereas a 9.1% contribution did. The multi-locus SNP genotypes generated using the ForenSeq™ DNA Signature Prep kit/Primer Mix B were shown to be reliable, reproducible, concordant and resulted in predictions that were also reliable, reproducible and concordant based on the limited number of donors (N = 19) used in this study.


Asunto(s)
Color del Ojo/genética , Genética Forense/instrumentación , Color del Cabello/genética , Polimorfismo de Nucleótido Simple , Grupos Raciales/genética , ADN , Femenino , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Fenotipo , Reproducibilidad de los Resultados , Análisis de Secuencia de ADN
20.
Forensic Sci Int ; 324: 110849, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34030000

RESUMEN

With the widespread use of STR in identification of individuals, paternity testing, as well as population genetics, many commercially robust and validated STR multiplex kits were developed. The AGCU Expressmarker 30 Kit is a new autosomal STR system that contains 29 autosomal STR loci (D3S1358, vWA, D1S1656, CSF1PO, D8S1132, D19S253, D3S3045, D8S1179, D21S11, D16S539, TPOX, D6S477, Penta D, D2S441, D5S818, TH01, FGA, D15S659, D22S1045, D19S433, D13S317, D7S820, D6S1043, D10S1435, D10S1248, D2S1338, D18S51, D12S391, and Penta E), one insertion/deletion polymorphic marker on the Y chromosome (Y indel), and the amelogenin locus. A series of validation studies were performed in this context according to the guidelines of "Validation Guidelines for Forensic DNA Analysis Methods". The sensitivity study showed that a full profile was observed with template DNA as low as 40 pg. In the stability study, all STR profiles were obtained at concentrations of humic acid up to 800 ng/µL, hematin up to 250 µM, and tannic acid up to 200 ng/µL. The mixture study demonstrated that all of the minor alleles could be called at ratios from 1:1-29:1 when the total DNA was 2 ng. In the population study, the total discrimination power for three population (Sichuan-Han, Gansu-Hui, and Guangxi-Zhuang) were above 0.9999999999999999999999999999999992, 0.999999999999999999999999999999998 and 0.999999999999999999999999999999994 as well as the cumulative probability of paternity exclusion were 0.999999999999953, 0.999999999999178, and 0.999999999999611 respectively. These results demonstrated that the AGCU Expressmarker 30 Kit is a useful tool for analyzing both forensic casework and database samples.


Asunto(s)
Dermatoglifia del ADN/instrumentación , Genética Forense/instrumentación , Repeticiones de Microsatélite , Animales , Etnicidad/genética , Humanos , Reacción en Cadena de la Polimerasa , Especificidad de la Especie
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