19 results match your criteria: "U.S. National Institute of Standards and Technology[Affiliation]"

Nontargeted Analysis Study Reporting Tool: A Framework to Improve Research Transparency and Reproducibility.

Anal Chem

October 2021

U.S. Environmental Protection Agency, 109 TW Alexander Drive, Research Triangle Park, Durham, North Carolina 27709, United States.

Non-targeted analysis (NTA) workflows using mass spectrometry are gaining popularity in many disciplines, but universally accepted reporting standards are nonexistent. Current guidance addresses limited elements of NTA reporting-most notably, identification confidence-and is insufficient to ensure scientific transparency and reproducibility given the complexity of these methods. This lack of reporting standards hinders researchers' development of thorough study protocols and reviewers' ability to efficiently assess grant and manuscript submissions.

View Article and Find Full Text PDF

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.

View Article and Find Full Text PDF

Determination of glyphosate and AMPA in oat products for the selection of candidate reference materials.

Food Chem

April 2021

U.S. National Institute of Standards and Technology, Chemical Sciences Division, 100 Bureau Drive, Gaithersburg, MD 20899-8392, USA. Electronic address:

The use of reference materials (RMs) is critical for validating and testing the accuracy of analytical protocols. The National Institute of Standards and Technology (NIST) is in initial stages of developing a glyphosate in oats RM. The first aim of this study was to optimize and validate a robust method for the extraction and analysis of glyphosate and aminomethylphosphonic acid (AMPA).

View Article and Find Full Text PDF

The application of massively parallel sequencing (MPS) to forensic genetics has led to improvements in multiple aspects of DNA analysis, however, additional complexities are concurrently associated with these advances. In relation to short tandem repeat (STR) typing, the move to sequence rather than length-based methodologies has highlighted the extent to which previous allelic variation was masked - both within and outside of the repeat regions (the flanking regions). In order to fully implement MPS for autosomal STR analysis, sequence-based allelic frequencies must be available, and concordance with previous typing techniques needs to be assessed.

View Article and Find Full Text PDF

Understanding the characteristics of sequence-based single-source DNA profiles.

Forensic Sci Int Genet

January 2020

U.S. National Institute of Standards and Technology, Biomolecular Measurement Division, 100 Bureau Drive, Gaithersburg, MD 20899-8314, USA.

The sequencing of STR markers provides additional information present in the underlying sequence variation that is typically masked by traditional fragment-based genotyping. However, the interpretation of STR profiles generated by targeted sequencing methods are susceptible to the same factors encountered in profiles processed through capillary gel electrophoresis. These factors include stochastic variation, noise, stutter artifacts, heterozygote imbalance, and allelic drop-out/in.

View Article and Find Full Text PDF

This report summarizes topics discussed at the STR sequence nomenclature meeting hosted by the STRAND Working Group in April 2019. Invited attendees for this meeting included researchers known-to-us to be developing STR sequence-based nomenclature schemata, scientific representatives from vendors developing STR sequence bioinformatic methods, DNA intelligence database curators, and academic experts in STR genomics. The goal of this meeting was to provide a forum for individuals developing nomenclature schemata to present and discuss their ideas, encouraging mutual awareness, identification of differences in approaches, opposing aspects, and opportunities for parallelization while some approaches are still under development.

View Article and Find Full Text PDF

Development and Characterization of a Multimycotoxin Reference Material.

J AOAC Int

November 2019

U.S. Food and Drug Administration (FDA), Center for Food Safety and Applied Nutrition, Office of Regulatory Science, College Park, MD.

Matrix-matched reference materials (RMs) are critical for adequate quality assurance of extraction, digestion, separation, and/or detection processes for analytes of interest in foods and dietary supplements. The accurate determination of mycotoxins in foods is an international concern. While RMs for mycotoxins are available from a variety of RM producers, these mainly address a single mycotoxin or group of mycotoxins and therefore require the use of multiple RMs for multitarget methods.

View Article and Find Full Text PDF

In recent years a number of computer-based algorithms have been developed for the deconvolution of complex DNA mixtures in forensic science. These procedures utilize likelihood ratios that quantify the evidence for a hypothesis for the presence of a person of interest in a DNA profile compared to an alternative hypothesis. Proper operation of these software systems requires an assumption regarding the total number of contributors present in the mixture.

View Article and Find Full Text PDF

Sequence-based U.S. population data for 27 autosomal STR loci.

Forensic Sci Int Genet

November 2018

U.S. National Institute of Standards and Technology, Biomolecular Measurement Division, 100 Bureau Drive, Gaithersburg, MD 20899, USA. Electronic address:

This manuscript reports Short Tandem Repeat (STR) sequence-based allele frequencies for 1036 samples across 27 autosomal STR loci: D1S1656, TPOX, D2S441, D2S1338, D3S1358, D4S2408, FGA, D5S818, CSF1PO, D6S1043, D7S820, D8S1179, D9S1122, D10S1248, TH01, vWA, D12S391, D13S317, Penta E, D16S539, D17S1301, D18S51, D19S433, D20S482, D21S11, Penta D, and D22S1045. Sequence data were analyzed by two bioinformatic pipelines and all samples have been evaluated for concordance with alleles derived from CE-based analysis at all loci. Each reported sequence includes high-quality flanking sequence and is properly formatted according to the most recent guidance of the International Society for Forensic Genetics.

View Article and Find Full Text PDF

A quantum future awaits.

Science

July 2018

Jacob M. Taylor is a Fellow at the U.S. National Institute of Standards and Technology, Gaithersburg, MD, and is assistant director for Quantum Information Science at the White House Office of Science and Technology Policy, Washington, DC.

View Article and Find Full Text PDF

We present a survey of multi-robot assembly applications and methods and describe trends and general insights into the multi-robot assembly problem for industrial applications. We focus on fixtureless assembly strategies featuring two or more robotic systems. Such robotic systems include industrial robot arms, dexterous robotic hands, and autonomous mobile platforms, such as automated guided vehicles.

View Article and Find Full Text PDF

STRSeq: A catalog of sequence diversity at human identification Short Tandem Repeat loci.

Forensic Sci Int Genet

November 2017

U.S. National Institute of Standards and Technology, Biomolecular Measurement Division, 100 Bureau Drive, Gaithersburg, MD 20899, USA. Electronic address:

The STR Sequencing Project (STRSeq) was initiated to facilitate the description of sequence-based alleles at the Short Tandem Repeat (STR) loci targeted in human identification assays. This international collaborative effort, which has been endorsed by the ISFG DNA Commission, provides a framework for communication among laboratories. The initial data used to populate the project are the aggregate alleles observed in targeted sequencing studies across four laboratories: National Institute of Standards and Technology (N=1786), Kings College London (N=1043), University of North Texas Health Sciences Center (N=839), and University of Santiago de Compostela (N=944), for a total of 4612 individuals.

View Article and Find Full Text PDF

Standard Reference Materials SRM 2392 and 2392-I are intended to provide quality control when amplifying and sequencing human mitochondrial genome sequences. The National Institute of Standards and Technology (NIST) offers these SRMs to laboratories performing DNA-based forensic human identification, molecular diagnosis of mitochondrial diseases, mutation detection, evolutionary anthropology, and genetic genealogy. The entire mtGenome (∼16569bp) of SRM 2392 and 2392-I have previously been characterized at NIST by Sanger sequencing.

View Article and Find Full Text PDF

Quantification of the total amount of human DNA isolated from a forensic evidence item is crucial for DNA normalization prior to short tandem repeat (STR) DNA analysis and a federal quality assurance standard requirement. Previous commercial quantification methods determine the total human DNA and total human male DNA concentrations, but provide limited information about the condition of the DNA sample. The PowerQuant(®) System includes targets for quantification of total human and total human male DNA as well as targets for evaluating whether the human DNA is degraded and/or PCR inhibitors are present in the sample.

View Article and Find Full Text PDF

D5S2500 is an ambiguously characterized STR: Identification and description of forensic microsatellites in the genomics age.

Forensic Sci Int Genet

July 2016

Institute of Applied Genetics, Department of Molecular and Medical Genetics, University of North Texas Health Science Center, 3500Camp Bowie Blvd., Fort Worth, TX 76107, USA; Center of Excellence in Genomic Medicine Research (CEGMR), King Abdulaziz University, Jeddah, Saudi Arabia.

In the process of establishing short tandem repeat (STR) sequence variant nomenclature guidelines in anticipation of expanded forensic multiplexes for massively parallel sequencing (MPS), it was discovered that the STR D5S2500 has multiple positions and genomic characteristics reported. This ambiguity is because the marker named D5S2500 consists of two different microsatellites forming separate components in the capillary electrophoresis multiplexes of Qiagen's HDplex (Hilden, Germany) and AGCU ScienTech's non-CODIS STR 21plex (Wuxi, Jiangsu, China). This study outlines the genomic details used to identify each microsatellite and reveals the D5S2500 marker in HDplex has the correctly assigned STR name, while the D5S2500 marker in the AGCU 21plex, closely positioned a further 1643 nucleotides in the human reference sequence, is an unnamed microsatellite.

View Article and Find Full Text PDF
Article Synopsis
  • Sequencing short tandem repeat (STR) loci provides detailed information on repeat variations that can't be detected through size-based PCR methods, making it valuable for forensic analysis.* -
  • While Sanger sequencing has been useful in research, it's too complex for routine forensic applications; however, advancements in next generation sequencing (NGS) methods are changing this.* -
  • An analysis of 183 DNA samples from diverse populations revealed that certain STR loci (like D12S391 and D2S1338) have significantly more alleles when sequenced, leading to improved discrimination in forensic applications.*
View Article and Find Full Text PDF

STR allele sequence variation: Current knowledge and future issues.

Forensic Sci Int Genet

September 2015

U.S. National Institute of Standards and Technology, Special Programs Office, 100 Bureau Drive, Gaithersburg, MD 20899, USA. Electronic address:

This article reviews what is currently known about short tandem repeat (STR) allelic sequence variation in and around the twenty-four loci most commonly used throughout the world to perform forensic DNA investigations. These STR loci include D1S1656, TPOX, D2S441, D2S1338, D3S1358, FGA, CSF1PO, D5S818, SE33, D6S1043, D7S820, D8S1179, D10S1248, TH01, vWA, D12S391, D13S317, Penta E, D16S539, D18S51, D19S433, D21S11, Penta D, and D22S1045. All known reported variant alleles are compiled along with genomic information available from GenBank, dbSNP, and the 1000 Genomes Project.

View Article and Find Full Text PDF

Performance of a next generation sequencing SNP assay on degraded DNA.

Forensic Sci Int Genet

November 2015

U.S. National Institute of Standards and Technology, Biomolecular Measurement Division, 100 Bureau Drive, Mail Stop 8314, Gaithersburg, MD 20899-8314, USA.

Forensic DNA casework samples are often of insufficient quantity or quality to generate full profiles by conventional DNA typing methods. Polymerase chain reaction (PCR) amplification of short tandem repeat (STR) loci is inherently limited in samples containing degraded DNA, as the cumulative size of repeat regions, primer binding regions, and flanking sequence is necessarily larger than the PCR template. Additionally, traditional capillary electrophoresis (CE) assay design further inherently limits shortening amplicons because the markers must be separated by size.

View Article and Find Full Text PDF

Effect of linkage between vWA and D12S391 in kinship analysis.

Forensic Sci Int Genet

December 2012

U.S. National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899-8314, United States.

Ideally for use in forensic analyses, genetic markers on the same chromosome should be more than 50 Mb in physical distance to ensure full recombination and thus independent inheritance. The forensic community has given attention to two STR markers, D12S391 and vWA, that are 6.3 megabases (Mb) apart on chromosome 12.

View Article and Find Full Text PDF