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1.
Genes (Basel) ; 13(2)2022 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-35205247

RESUMO

This study describes an optimized DNA extraction protocol targeting ultrashort DNA molecules from single rootless hairs. It was applied to the oldest samples available to us: locks of hairs that were found in relics associated with the Romanov family. Published mitochondrial DNA genome sequences of Tsar Nicholas II and his wife, Tsarina Alexandra, made these samples ideal to assess this DNA extraction protocol and evaluate the types of genetic information that can be recovered by sequencing ultrashort fragments. Using this method, the mtGenome of the Tsarina's lineage was identified in hairs that were concealed in a pendant made by Karl Fabergé for Alexandra Feodorovna Romanov. In addition, to determine if the lock originated from more than one individual, two hairs from the locket were extracted independently and converted into Illumina libraries for shotgun sequencing on a NextSeq 500 platform. From these data, autosomal SNPs were analyzed to assess relatedness. The results indicated that the two hairs came from a single individual. Genetic testing of hairs that were found in the second artifact, a framed photograph of Louise of Hesse-Kassel, Queen of Denmark and maternal grandmother of Tsar Nicholas II, revealed that the hair belonged to a woman who shared Tsar Nicholas' maternal lineage, including the well-known point heteroplasmy at position 16169.


Assuntos
Genoma Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Pessoas Famosas , Feminino , Cabelo/química , Heteroplasmia , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Polimorfismo de Nucleotídeo Único , Federação Russa
2.
Nucleic Acids Res ; 49(3): 1517-1531, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-33450006

RESUMO

The maternal mode of mitochondrial DNA (mtDNA) inheritance is central to human genetics. Recently, evidence for bi-parental inheritance of mtDNA was claimed for individuals of three pedigrees that suffered mitochondrial disorders. We sequenced mtDNA using both direct Sanger and Massively Parallel Sequencing in several tissues of eleven maternally related and other affiliated healthy individuals of a family pedigree and observed mixed mitotypes in eight individuals. Cells without nuclear DNA, i.e. thrombocytes and hair shafts, only showed the mitotype of haplogroup (hg) V. Skin biopsies were prepared to generate ρ° cells void of mtDNA, sequencing of which resulted in a hg U4c1 mitotype. The position of the Mega-NUMT sequence was determined by fluorescence in situ hybridization and two different quantitative PCR assays were used to determine the number of contributing mtDNA copies. Thus, evidence for the presence of repetitive, full mitogenome Mega-NUMTs matching haplogroup U4c1 in various tissues of eight maternally related individuals was provided. Multi-copy Mega-NUMTs mimic mixtures of mtDNA that cannot be experimentally avoided and thus may appear in diverse fields of mtDNA research and diagnostics. We demonstrate that hair shaft mtDNA sequencing provides a simple but reliable approach to exclude NUMTs as source of misleading results.


Assuntos
DNA Mitocondrial , Genoma Humano , Núcleo Celular/genética , Variações do Número de Cópias de DNA , Feminino , Humanos , Masculino , Linhagem , Análise de Sequência de DNA
3.
Forensic Sci Int Genet ; 44: 102151, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31629185

RESUMO

As a first step towards integrating next generation sequencing (NGS) technology into the FBI Laboratory's operational casework, the PowerSeq™ CRM Nested System, an NGS-based mitochondrial DNA (mtDNA) control region assay, was developmentally and internally validated. The validation studies were conducted in accordance with the Scientific Working Group on DNA Analysis Methods (SWGDAM) Validation Guidelines for Forensic DNA Analysis Methods, and the FBI's Quality Assurance Standards (QAS) for Forensic DNA Testing Laboratories. The assay was shown to be highly reproducible, with variant frequencies across intra and inter-run replicates of the same sample differing, on average, by just 0.3% for substitutions and point heteroplasmies and 1.5% for insertions and deletions. The assay was also shown to be extremely sensitive, yielding complete control region sequence data from as few as 2000 copies of mtDNA. This is a more than 20-fold increase in sensitivity when compared to the FBI Laboratory's current Sanger sequencing-based protocols and, based on mtDNA quantitation values of samples routinely encountered in mtDNA casework, suggests that the percentage of questioned samples from which full control region data can be recovered will increase from our current 20% to approximately 90% success with NGS technology. In addition, the assay requires on average only 30% of the extract volume typically required to develop control region profiles from degraded samples via Sanger sequencing. Overall, these studies establish the reliability of the PowerSeq™ CRM Nested System for accurate mtDNA control region typing and can serve as a model for laboratories seeking to validate NGS protocols for forensic mtDNA analysis.


Assuntos
DNA Mitocondrial/genética , Sequenciamento de Nucleotídeos em Larga Escala , Laboratórios , Animais , Osso e Ossos/química , Contaminação por DNA , Órgãos Governamentais , Cabelo/química , Haplótipos , Humanos , Região de Controle de Locus Gênico , Mucosa Bucal/química , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise de Sequência de DNA , Especificidade da Espécie , Estados Unidos
4.
Forensic Sci Int Genet ; 42: 99-102, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31284104

RESUMO

This study investigated the mitochondrial DNA (mtDNA) control region variation in Middle Eastern populations (610 individuals from Lebanon, Jordan and the Kingdom of Bahrain) for which population data are scarce. FST comparison among populations revealed that there are significant differences in mtDNA distributions between Bahrain and the two other populations, while Lebanon and Jordan showed no significant differences. This was also reflected by the distribution of the observed lineages that differed prominently between Bahrain and the other two investigated populations. Jordan and Lebanon fit the hitherto known genetic results of the Levant population. Data are available via EMPOP (https://empop.online) and GenBank.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Barein , Genética Populacional , Haplótipos , Humanos , Jordânia , Líbano , Filogenia , Análise de Sequência de DNA
5.
Genes (Basel) ; 9(12)2018 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-30567392

RESUMO

While shed hairs are one of the most commonly encountered evidence types, they are among the most limited in terms of DNA quantity and quality. As a result, nuclear DNA short tandem repeat (STR) profiling is generally unsuccessful and DNA testing of shed hair is instead performed by targeting the mitochondrial DNA control region. Although the high copy number of mitochondrial DNA relative to nuclear DNA routinely permits the recovery of mitochondrial DNA (mtDNA) data in these cases, mtDNA profiles do not offer the discriminatory power of nuclear DNA profiles. In order to better understand the total content and degradation state of DNA in single shed hairs and assess the feasibility of recovering highly discriminatory nuclear DNA data from this common evidence type, high throughput shotgun sequencing was performed on both recently collected and aged (approximately 50-year-old) hair samples. The data reflect trends that have been demonstrated previously with other technologies, namely that mtDNA quantity and quality decrease along the length of the hair shaft. In addition, the shotgun data reveal that nuclear DNA is present in shed hair and surprisingly abundant relative to mitochondrial DNA, even in the most distal fragments. Nuclear DNA comprised, at minimum, 88% of the total human reads in any given sample, and generally more than 95%. Here, we characterize both the nuclear and mitochondrial DNA content of shed hairs and discuss the implications of these data for forensic investigations.

6.
Forensic Sci Int Genet ; 34: 197-205, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29525576

RESUMO

Some of the expected advantages of next generation sequencing (NGS) for short tandem repeat (STR) typing include enhanced mixture detection and genotype resolution via sequence variation among non-homologous alleles of the same length. However, at the same time that NGS methods for forensic DNA typing have advanced in recent years, many caseworking laboratories have implemented or are transitioning to probabilistic genotyping to assist the interpretation of complex autosomal STR typing results. Current probabilistic software programs are designed for length-based data, and were not intended to accommodate sequence strings as the product input. Yet to leverage the benefits of NGS for enhanced genotyping and mixture deconvolution, the sequence variation among same-length products must be utilized in some form. Here, we propose use of the longest uninterrupted stretch (LUS) in allele designations as a simple method to represent sequence variation within the STR repeat regions and facilitate - in the nearterm - probabilistic interpretation of NGS-based typing results. An examination of published population data indicated that a reference LUS region is straightforward to define for most autosomal STR loci, and that using repeat unit plus LUS length as the allele designator can represent greater than 80% of the alleles detected by sequencing. A proof of concept study performed using a freely available probabilistic software demonstrated that the LUS length can be used in allele designations when a program does not require alleles to be integers, and that utilizing sequence information improves interpretation of both single-source and mixed contributor STR typing results as compared to using repeat unit information alone. The LUS concept for allele designation maintains the repeat-based allele nomenclature that will permit backward compatibility to extant STR databases, and the LUS lengths themselves will be concordant regardless of the NGS assay or analysis tools employed. Further, these biologically based, easy-to-derive designations uphold clear relationships between parent alleles and their stutter products, enabling analysis in fully continuous probabilistic programs that model stutter while avoiding the algorithmic complexities that come with string based searches. Though using repeat unit plus LUS length as the allele designator does not capture variation that occurs outside of the core repeat regions, this straightforward approach would permit the large majority of known STR sequence variation to be used for mixture deconvolution and, in turn, result in more informative mixture statistics in the near term. Ultimately, the method could bridge the gap from current length-based probabilistic systems to facilitate broader adoption of NGS by forensic DNA testing laboratories.


Assuntos
Alelos , Impressões Digitais de DNA/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Repetições de Microssatélites , Análise de Sequência de DNA , Variação Genética , Genótipo , Humanos , Probabilidade
7.
Genes (Basel) ; 9(3)2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29494531

RESUMO

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.

8.
Forensic Sci Int Genet ; 28: 1-9, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28126691

RESUMO

Though the utility of next-generation sequencing (NGS) technologies for forensic short tandem repeat (STR) typing has been evident for several years, commercially available assays and software solutions developed specifically to meet forensic needs have only recently become available. One of these, the ForenSeq™ DNA Signature Prep Kit (Illumina, Inc.) sequences 27 autosomal STR (aSTR) and 24 Y chromosome STR (Y-STR) loci (concurrent with additional nuclear markers) per multiplexed sample, with automated secondary and tertiary analyses of the data accomplished via the associated ForenSeq™ Universal Analysis Software (UAS). In this study we investigated the performance of the ForenSeq system for aSTR and Y-STR typing by examination of 151 sample libraries developed from high quality DNAs amplified at the target 1ng template. Utilizing PCR Primer Mix B, greater than 99.5% of aSTR loci and 97.0% of Y-STR loci were recovered when 42 or fewer sample libraries were pooled for sequencing. A direct comparison of UAS developed fragment length results to capillary electrophoresis (CE) based data identified only two allele call discrepancies when no UAS quality flag was triggered. Review of the ForenSeq data indicated that most samples with total sequence read counts exceeding 40,000 could be interpreted to develop nearly complete aSTR genotypes or Y-STR haplotypes. However, markers D22S1045 and DYS392 produced poor or inconsistent results even when sample read counts were greater than 85,000. Excluding these two loci, analyst-interpreted aSTR and Y-STR ForenSeq profiles were 99.96% and 100% concordant, respectively, with CE data. In addition to demonstrating concordance on par with other CE kit to kit comparisons, the results from this study will assist laboratories seeking to develop workflows for high volume processing and analysis of aSTRs and Y-STRs from reference-type specimens using the ForenSeq system.


Assuntos
Cromossomos Humanos Y , Impressões Digitais de DNA , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Repetições de Microssatélites , Alelos , Eletroforese Capilar , Genótipo , Haplótipos , Humanos , Masculino , Reação em Cadeia da Polimerase Multiplex
9.
Forensic Sci Int Genet ; 24: 103-111, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27368088

RESUMO

Sanger-type sequencing (STS) of mitochondrial DNA (mtDNA), specifically the control region (CR), is routinely employed in forensics in human identification and missing persons scenarios. Yet next-generation sequencing (NGS) has the potential to overcome some of the major limitations of STS processing, permitting reasonable paths forward for full mitochondrial genome (mtGenome) sequencing, while also offering higher-throughput and higher sensitivity capabilities. To establish the accuracy and reproducibility of NGS for the development of mtDNA data, 90 DNA extracts that were previously used to generate forensic quality full mtGenomes using STS were sequenced using Nextera XT library preparation and the Illumina MiSeq. Using the same amplicon product, replicate library sets were generated and sequenced at different laboratories, and analysis was performed in replicate using the CLC Genomics Workbench. Both sequencing sets resulted in 99.998% of positions with greater than 10X coverage when 96 samples (including controls) were multiplexed. Overall, 99.9996% concordance was observed between the NGS data and the STS data for the full mtGenome. The only "discordant" calls involved low level point heteroplasmies, with the differences resulting from stochastic variation and/or the increased sensitivity of NGS. Higher sensitivity also allowed for the detection of a mixed sample previously not detected with STS. Additionally, variant calls were reproducible between sequencing sets and between software analysis versions with the variant frequency only differing by 0.23% and 0.01%, respectively. Further validation studies and specialized software functionality tailored to forensic practice should facilitate the incorporation of NGS processing into standard casework applications. The data herein comprise the largest, and likely most thoroughly examined, complete mtGenome STS-NGS concordance dataset available.


Assuntos
DNA Mitocondrial/genética , Genoma Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Análise de Sequência de DNA , Humanos , Reação em Cadeia da Polimerase , Reprodutibilidade dos Testes
10.
Forensic Sci Int Genet ; 22: 54-63, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26844919

RESUMO

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.


Assuntos
Genética Forense/métodos , Genética Forense/normas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Terminologia como Assunto , DNA/genética , Bases de Dados de Ácidos Nucleicos/normas , Genótipo , Humanos , Repetições de Microssatélites/genética , Polimorfismo Genético
11.
Forensic Sci Int Genet ; 18: 131-9, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26009256

RESUMO

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.


Assuntos
DNA Mitocondrial/genética , Genética Forense/métodos , Genoma Mitocondrial/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , DNA Mitocondrial/análise , Genoma Humano , Humanos , Mitocôndrias/química , Mitocôndrias/genética , Análise de Sequência de DNA
12.
Forensic Sci Int Genet ; 14: 141-55, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25450785

RESUMO

Though investigations into the use of massively parallel sequencing technologies for the generation of complete mitochondrial genome (mtGenome) profiles from difficult forensic specimens are well underway in multiple laboratories, the high quality population reference data necessary to support full mtGenome typing in the forensic context are lacking. To address this deficiency, we have developed 588 complete mtGenome haplotypes, spanning three U.S. population groups (African American, Caucasian and Hispanic) from anonymized, randomly-sampled specimens. Data production utilized an 8-amplicon, 135 sequencing reaction Sanger-based protocol, performed in semi-automated fashion on robotic instrumentation. Data review followed an intensive multi-step strategy that included a minimum of three independent reviews of the raw data at two laboratories; repeat screenings of all insertions, deletions, heteroplasmies, transversions and any additional private mutations; and a check for phylogenetic feasibility. For all three populations, nearly complete resolution of the haplotypes was achieved with full mtGenome sequences: 90.3-98.8% of haplotypes were unique per population, an improvement of 7.7-29.2% over control region sequencing alone, and zero haplotypes overlapped between populations. Inferred maternal biogeographic ancestry frequencies for each population and heteroplasmy rates in the control region were generally consistent with published datasets. In the coding region, nearly 90% of individuals exhibited length heteroplasmy in the 12418-12425 adenine homopolymer; and despite a relatively high rate of point heteroplasmy (23.8% of individuals across the entire molecule), coding region point heteroplasmies shared by more than one individual were notably absent, and transversion-type heteroplasmies were extremely rare. The ratio of nonsynonymous to synonymous changes among point heteroplasmies in the protein-coding genes (1:1.3) and average pathogenicity scores in comparison to data reported for complete substitutions in previous studies seem to provide some additional support for the role of purifying selection in the evolution of the human mtGenome. Overall, these thoroughly vetted full mtGenome population reference data can serve as a standard against which the quality and features of future mtGenome datasets (especially those developed via massively parallel sequencing) may be evaluated, and will provide a solid foundation for the generation of complete mtGenome haplotype frequency estimates for forensic applications.


Assuntos
Genética Forense , Genoma Mitocondrial , Haplótipos , Humanos , Estados Unidos
13.
Forensic Sci Int Genet ; 15: 8-15, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25438934

RESUMO

Though shed hairs are one of the most commonly encountered evidence types, they are among the most limited in terms of DNA quantity and quality. As a result, DNA testing has historically focused on the recovery of just about 600 base pairs of the mitochondrial DNA control region. Here, we describe our success in recovering complete mitochondrial genome (mtGenome) data (∼16,569bp) from single shed hairs. By employing massively parallel sequencing (MPS), we demonstrate that particular hair samples yield DNA sufficient in quantity and quality to produce 2-3kb mtGenome amplicons and that entire mtGenome data can be recovered from hair extracts even without PCR enrichment. Most importantly, we describe a small amplicon multiplex assay comprised of sixty-two primer sets that can be routinely applied to the compromised hair samples typically encountered in forensic casework. In all samples tested here, the MPS data recovered using any one of the three methods were consistent with the control Sanger sequence data developed from high quality known specimens. Given the recently demonstrated value of complete mtGenome data in terms of discrimination power among randomly sampled individuals, the possibility of recovering mtGenome data from the most compromised and limited evidentiary material is likely to vastly increase the utility of mtDNA testing for hair evidence.


Assuntos
DNA Mitocondrial/genética , Genética Forense , Genoma Mitocondrial , Cabelo/química , Sequenciamento de Nucleotídeos em Larga Escala , Humanos
15.
Forensic Sci Int Genet ; 12: 107-19, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24908576

RESUMO

To investigate the feasibility of next generation sequencing technology (NGS) for the multiplex detection and sequence production of short tandem repeats (STRs) from degraded and low DNA quantity samples, standard polymerase chain reaction amplification methods were used to enrich for commonly employed STR markers. Samples were amplified with two multiplexing strategies: a multiplex containing thirteen miniSTR markers and a series of multiplexes containing four miniSTR markers each. Each sample multiplex was barcoded with a sample-specific multiplex identifier for subsequent parallel tagged sequencing on the GS Junior System (454 Life Sciences, a Roche company, Branford, CT). Sequencing results from over fifty DNA extracts representing both pristine samples and low-quality evidentiary specimens reflected known genotypes and were consistent across multiple extracts and/or amplifications of the same sample. Furthermore, the NGS data revealed sequence information not available with standard capillary electrophoresis-based detection alone. For the population samples tested, a total of 152 single nucleotide polymorphisms or insertions/deletions were identified in over 935 recovered alleles, averaging one polymorphism for every six recovered alleles. For three of the loci, the sequence information doubled the number of alleles detected via traditional STR typing by fragment analysis. In addition, twenty-eight of these variants were only seen once within our dataset, highlighting the potential for discrimination among individuals. These additional data are likely to be particularly valuable in missing persons and disaster victim identification cases for which only partial profiles may be recovered and/or only distant kin are available as references. And, considering the opportunity to target only small amplicons with NGS, this type of STR typing will allow for greater information recovery from challenging casework samples. While our results highlight the potential of new technologies for recovering discriminatory genetic information from evidentiary specimens, our data also reveal the complexities of NGS-based STR typing, both in terms of the laboratory assays themselves as well as the downstream data processing and analysis.


Assuntos
Genética Forense , Repetições de Microssatélites , Marcadores Genéticos , Humanos
16.
Forensic Sci Int Genet ; 10: 73-79, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24637383

RESUMO

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.


Assuntos
DNA Mitocondrial/genética , Genética Forense , Genoma Humano , Haplótipos , Humanos
17.
Int J Legal Med ; 128(5): 745-6, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24573746

RESUMO

Mitochondrial DNA (mtDNA) control region (16024-576) sequences were generated from 281 individuals from South Korea. Robotic liquid handling, a redundant sequencing strategy, and a series of quality control checks were implemented to ensure the high quality of the dataset. This population sample showed a low random match probability (0.25 %) and high genetic diversity (0.9933). The haplogroup breakdown was consistent with previous studies describing Korean mtDNA variation. The 224 unique haplotypes (33 shared) presented will supplement the data already publically available.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Povo Asiático/genética , Haplótipos , Humanos , República da Coreia , Análise de Sequência de DNA
18.
Artigo em Inglês | MEDLINE | ID: mdl-26898381

RESUMO

The Publisher regrets that this article is an accidental duplication of an article that has already been published, http://dx.doi.org/10.1016/j.fsigen.2013.09.007. The duplicate article has therefore been withdrawn. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

19.
BMC Genomics ; 14: 881, 2013 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-24341507

RESUMO

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.


Assuntos
Genoma Mitocondrial , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA/métodos , Haplótipos , Humanos , Robótica
20.
Forensic Sci Int Genet ; 7(6): 632-639, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24119954

RESUMO

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 64mtGenomes (>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.

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