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1.
Phys Rev Lett ; 128(2): 021601, 2022 Jan 14.
Article in English | MEDLINE | ID: mdl-35089733

ABSTRACT

We find rotating black hole solutions in the Randall-Sundrum II (RSII) model, by numerically solving a three-dimensional PDE problem using pseudospectral collocation methods. We compute the area and equatorial innermost stable orbits of these solutions. For large black holes compared with the AdS length scale ℓ the black hole exhibits four-dimensional behavior, approaching the Kerr metric on the brane, while for small black holes, the solution tends instead towards a five-dimensional Myers-Perry black hole with a single nonzero rotation parameter aligned with the brane. This departure from exact four-dimensional gravity may lead to different phenomenological predictions for rotating black holes in the RSII model to those in standard four-dimensional general relativity. This Letter provides a stepping stone for studying such modifications.

2.
Diabetes Care ; 44(12): 2729-2737, 2021 12.
Article in English | MEDLINE | ID: mdl-34588210

ABSTRACT

OBJECTIVE: To explore the effect of discontinuing continuous glucose monitoring (CGM) after 8 months of CGM use in adults with type 2 diabetes treated with basal without bolus insulin. RESEARCH DESIGN AND METHODS: This multicenter trial had an initial randomization to either real-time CGM or blood glucose monitoring (BGM) for 8 months followed by 6 months in which the BGM group continued to use BGM (n = 57) and the CGM group was randomly reassigned either to continue CGM (n = 53) or discontinue CGM with resumption of BGM for glucose monitoring (n = 53). RESULTS: In the group that discontinued CGM, mean time in range (TIR) 70-180 mg/dL, which improved from 38% before initiating CGM to 62% after 8 months of CGM, decreased after discontinuing CGM to 50% at 14 months (mean change from 8 to 14 months -12% [95% CI -21% to -3%], P = 0.01). In the group that continued CGM use, little change was found in TIR from 8 to 14 months (baseline 44%, 8 months 56%, 14 months 57%, mean change from 8 to 14 months 1% [95% CI -11% to 12%], P = 0.89). Comparing the two groups at 14 months, the adjusted treatment group difference in mean TIR was -6% (95% CI -16% to 4%, P = 0.20). CONCLUSIONS: In adults with type 2 diabetes treated with basal insulin who had been using real-time CGM for 8 months, discontinuing CGM resulted in a loss of about one-half of the initial gain in TIR that had been achieved during CGM use.


Subject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Adult , Blood Glucose , Blood Glucose Self-Monitoring/methods , Diabetes Mellitus, Type 2/drug therapy , Glycated Hemoglobin/analysis , Humans , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use
3.
JAMA ; 325(22): 2262-2272, 2021 06 08.
Article in English | MEDLINE | ID: mdl-34077499

ABSTRACT

Importance: Continuous glucose monitoring (CGM) has been shown to be beneficial for adults with type 2 diabetes using intensive insulin therapy, but its use in type 2 diabetes treated with basal insulin without prandial insulin has not been well studied. Objective: To determine the effectiveness of CGM in adults with type 2 diabetes treated with basal insulin without prandial insulin in primary care practices. Design, Setting, and Participants: This randomized clinical trial was conducted at 15 centers in the US (enrollment from July 30, 2018, to October 30, 2019; follow-up completed July 7, 2020) and included adults with type 2 diabetes receiving their diabetes care from a primary care clinician and treated with 1 or 2 daily injections of long- or intermediate-acting basal insulin without prandial insulin, with or without noninsulin glucose-lowering medications. Interventions: Random assignment 2:1 to CGM (n = 116) or traditional blood glucose meter (BGM) monitoring (n = 59). Main Outcomes and Measures: The primary outcome was hemoglobin A1c (HbA1c) level at 8 months. Key secondary outcomes were CGM-measured time in target glucose range of 70 to 180 mg/dL, time with glucose level at greater than 250 mg/dL, and mean glucose level at 8 months. Results: Among 175 randomized participants (mean [SD] age, 57 [9] years; 88 women [50%]; 92 racial/ethnic minority individuals [53%]; mean [SD] baseline HbA1c level, 9.1% [0.9%]), 165 (94%) completed the trial. Mean HbA1c level decreased from 9.1% at baseline to 8.0% at 8 months in the CGM group and from 9.0% to 8.4% in the BGM group (adjusted difference, -0.4% [95% CI, -0.8% to -0.1%]; P = .02). In the CGM group, compared with the BGM group, the mean percentage of CGM-measured time in the target glucose range of 70 to 180 mg/dL was 59% vs 43% (adjusted difference, 15% [95% CI, 8% to 23%]; P < .001), the mean percentage of time at greater than 250 mg/dL was 11% vs 27% (adjusted difference, -16% [95% CI, -21% to -11%]; P < .001), and the means of the mean glucose values were 179 mg/dL vs 206 mg/dL (adjusted difference, -26 mg/dL [95% CI, -41 to -12]; P < .001). Severe hypoglycemic events occurred in 1 participant (1%) in the CGM group and in 1 (2%) in the BGM group. Conclusions and Relevance: Among adults with poorly controlled type 2 diabetes treated with basal insulin without prandial insulin, continuous glucose monitoring, as compared with blood glucose meter monitoring, resulted in significantly lower HbA1c levels at 8 months. Trial Registration: ClinicalTrials.gov Identifier: NCT03566693.


Subject(s)
Blood Glucose/analysis , Diabetes Mellitus, Type 2/drug therapy , Glycemic Control/methods , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Aged , Confidence Intervals , Diabetes Mellitus, Type 2/blood , Female , Glycated Hemoglobin/analysis , Humans , Male , Middle Aged , Patient Satisfaction , Postprandial Period , Sample Size , Time Factors , Treatment Outcome
5.
Clin Diabetes ; 37(3): 269-275, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31371858

ABSTRACT

IN BRIEF Therapeutic inertia and suboptimal treatment adherence remain the key drivers of chronic poor diabetes control. Advances in mHealth technologies have spurred the development of a new generation of blood glucose monitoring systems that enable individuals with diabetes to automatically transfer glucose data and other information from their smartphones to their health care providers for analysis and interpretation via diabetes data-management software. This report discusses key lessons learned from two investigations that assessed the effects of interventions using the Accu-Chek Connect diabetes-management system (Roche Diabetes Care, Indianapolis, Ind.) within diverse diabetes populations.

6.
Nat Microbiol ; 4(11): 1790-1797, 2019 11.
Article in English | MEDLINE | ID: mdl-31308524

ABSTRACT

Diatoms are among the most globally distributed and ecologically successful organisms in the modern ocean, contributing upwards of 40% of total marine primary productivity1,2. By converting dissolved silicon into biogenic silica, and photosynthetically fixing carbon dioxide into particulate organic carbon, diatoms effectively couple the silicon (Si) and carbon cycles and ballast substantial vertical flux of carbon out of the euphotic zone into the mesopelagic and deep ocean3-5. Viruses are key players in ocean biogeochemical cycles6,7, yet little is known about how viral infection specifically impacts diatom populations. Here, we show that Si limitation facilitates virus infection and mortality in diatoms in the highly productive coastal waters of the California Current Ecosystem. Using metatranscriptomic analysis of cell-associated diatom viruses and targeted quantification of extracellular viruses, we found a link between Si stress and the early, active and lytic stages of viral infection. This relationship was also observed in cultures of the bloom-forming diatom Chaetoceros tenuissimus, where Si stress accelerated virus-induced mortality. Together, these findings contextualize viruses within the ecophysiological framework of Si availability and diatom-mediated biogeochemical cycling.


Subject(s)
Diatoms/growth & development , Gene Expression Profiling/methods , Silicon/metabolism , Viruses/pathogenicity , Biodegradation, Environmental , California , Carbon/metabolism , Carbon Dioxide , Diatoms/metabolism , Diatoms/virology , Metagenomics , Sequence Analysis, RNA , Viruses/classification , Viruses/genetics
7.
Blood Adv ; 2(19): 2419-2429, 2018 10 09.
Article in English | MEDLINE | ID: mdl-30262602

ABSTRACT

Allogeneic hematopoietic stem cell transplantation (allo-HCT) is a curative option for blood cancers, but the coupled effects of graft-versus-tumor and graft-versus-host disease (GVHD) limit its broader application. Outcomes improve with matching at HLAs, but other factors are required to explain residual risk of GVHD. In an effort to identify genetic associations outside the major histocompatibility complex, we conducted a genome-wide clinical outcomes study on 205 acute myeloid leukemia patients and their fully HLA-A-, HLA-B-, HLA-C-, HLA-DRB1-, and HLA-DQB1-matched (10/10) unrelated donors. HLA-DPB1 T-cell epitope permissibility mismatches were observed in less than half (45%) of acute GVHD cases, motivating a broader search for genetic factors affecting clinical outcomes. A novel bioinformatics workflow adapted from neoantigen discovery found no associations between acute GVHD and known, HLA-restricted minor histocompatibility antigens (MiHAs). These results were confirmed with microarray data from an additional 988 samples. On the other hand, Y-chromosome-encoded single-nucleotide polymorphisms in 4 genes (PCDH11Y, USP9Y, UTY, and NLGN4Y) did associate with acute GVHD in male patients with female donors. Males in this category with acute GVHD had more Y-encoded variant peptides per patient with higher predicted HLA-binding affinity than males without GVHD who matched X-paralogous alleles in their female donors. Methods and results described here have an immediate impact for allo-HCT, warranting further development and larger genomic studies where MiHAs are clinically relevant, including cancer immunotherapy, solid organ transplant, and pregnancy.


Subject(s)
Antigens/genetics , Genes, Y-Linked , Genetic Association Studies , Genetic Predisposition to Disease , Graft vs Host Disease/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Acute Disease , Alleles , Amino Acid Sequence , Antigens/immunology , Chromosome Mapping , Female , HLA Antigens/chemistry , HLA Antigens/genetics , HLA Antigens/immunology , Histocompatibility Testing , Humans , Male , Minor Histocompatibility Antigens/chemistry , Minor Histocompatibility Antigens/genetics , Minor Histocompatibility Antigens/immunology , Transplantation Conditioning/methods , Transplantation, Homologous
8.
Sci Rep ; 8(1): 4333, 2018 03 12.
Article in English | MEDLINE | ID: mdl-29531289

ABSTRACT

Urine culture and microscopy techniques are used to profile the bacterial species present in urinary tract infections. To gain insight into the urinary flora, we analyzed clinical laboratory features and the microbial metagenome of 121 clean-catch urine samples. 16S rDNA gene signatures were successfully obtained for 116 participants, while metagenome sequencing data was successfully generated for samples from 49 participants. Although 16S rDNA sequencing was more sensitive, metagenome sequencing allowed for a more comprehensive and unbiased representation of the microbial flora, including eukarya and viral pathogens, and of bacterial virulence factors. Urine samples positive by metagenome sequencing contained a plethora of bacterial (median 41 genera/sample), eukarya (median 2 species/sample) and viral sequences (median 3 viruses/sample). Genomic analyses suggested cases of infection with potential pathogens that are often missed during routine urine culture due to species specific growth requirements. While conventional microbiological methods are inadequate to identify a large diversity of microbial species that are present in urine, genomic approaches appear to more comprehensively and quantitatively describe the urinary microbiome.


Subject(s)
Bacteria/classification , Eukaryota/classification , Metagenome , Urinary Tract Infections/microbiology , Urinary Tract Infections/virology , Viruses/classification , Bacteria/genetics , Bacteria/isolation & purification , DNA, Ribosomal/genetics , Eukaryota/genetics , Eukaryota/isolation & purification , Female , Humans , Male , Phylogeny , Sequence Analysis, DNA , Urinary Tract Infections/parasitology , Urinary Tract Infections/urine , Viruses/genetics , Viruses/isolation & purification
9.
Proc Natl Acad Sci U S A ; 115(14): 3686-3691, 2018 04 03.
Article in English | MEDLINE | ID: mdl-29555771

ABSTRACT

Reducing premature mortality associated with age-related chronic diseases, such as cancer and cardiovascular disease, is an urgent priority. We report early results using genomics in combination with advanced imaging and other clinical testing to proactively screen for age-related chronic disease risk among adults. We enrolled active, symptom-free adults in a study of screening for age-related chronic diseases associated with premature mortality. In addition to personal and family medical history and other clinical testing, we obtained whole-genome sequencing (WGS), noncontrast whole-body MRI, dual-energy X-ray absorptiometry (DXA), global metabolomics, a new blood test for prediabetes (Quantose IR), echocardiography (ECHO), ECG, and cardiac rhythm monitoring to identify age-related chronic disease risks. Precision medicine screening using WGS and advanced imaging along with other testing among active, symptom-free adults identified a broad set of complementary age-related chronic disease risks associated with premature mortality and strengthened WGS variant interpretation. This and other similarly designed screening approaches anchored by WGS and advanced imaging may have the potential to extend healthy life among active adults through improved prevention and early detection of age-related chronic diseases (and their risk factors) associated with premature mortality.


Subject(s)
Disease/genetics , Genetic Predisposition to Disease , Image Processing, Computer-Assisted/methods , Mutation , Precision Medicine/methods , Whole Genome Sequencing/methods , Adult , Aged , Aged, 80 and over , Cardiovascular Diseases/diagnostic imaging , Cardiovascular Diseases/genetics , Cardiovascular Diseases/pathology , Disease/classification , Female , High-Throughput Nucleotide Sequencing , Humans , Male , Middle Aged , Neoplasms/diagnostic imaging , Neoplasms/genetics , Neoplasms/pathology , Nervous System Diseases/diagnostic imaging , Nervous System Diseases/genetics , Nervous System Diseases/pathology , Risk Assessment , Sequence Analysis, RNA , Young Adult
10.
Nat Genet ; 50(3): 333-337, 2018 03.
Article in English | MEDLINE | ID: mdl-29483654

ABSTRACT

Understanding the significance of genetic variants in the noncoding genome is emerging as the next challenge in human genomics. We used the power of 11,257 whole-genome sequences and 16,384 heptamers (7-nt motifs) to build a map of sequence constraint for the human species. This build differed substantially from traditional maps of interspecies conservation and identified regulatory elements among the most constrained regions of the genome. Using new Hi-C experimental data, we describe a strong pattern of coordination over 2 Mb where the most constrained regulatory elements associate with the most essential genes. Constrained regions of the noncoding genome are up to 52-fold enriched for known pathogenic variants as compared to unconstrained regions (21-fold when compared to the genome average). This map of sequence constraint across thousands of individuals is an asset to help interpret noncoding elements in the human genome, prioritize variants and reconsider gene units at a larger scale.


Subject(s)
Genetic Variation , Genome, Human , RNA, Untranslated/genetics , Chromosome Mapping/methods , Computational Biology , Conserved Sequence , Evolution, Molecular , Female , Humans , Male , Regulatory Sequences, Nucleic Acid
11.
Clin Transl Gastroenterol ; 9(1): e132, 2018 Jan 18.
Article in English | MEDLINE | ID: mdl-29345635

ABSTRACT

OBJECTIVES: Inflammatory bowel diseases (IBD), comprised of Crohn's disease (CD) and ulcerative colitis (UC), are characterized by a complex pathophysiology that is thought to result from an aberrant immune response to a dysbiotic luminal microbiota in genetically susceptible individuals. New technologies support the joint assessment of host-microbiome interaction. METHODS: Using whole genome sequencing and shotgun metagenomics, we studied the clinical features, host genome, and stool microbial metagenome of 85 IBD patients, and compared the results to 146 control individuals. Genetic risk scores, computed on 159 single nucleotide variants, and human leukocyte antigen (HLA) types differentiated IBD patients from healthy controls. RESULTS: Genetic risk was associated with the need for use of biologics in IBD and, modestly, with the composition of the gut microbiome. As compared with healthy controls, IBD patients had hallmarks of stool microbiome dysbiosis, with loss of a diversified core microbiome, enrichment and depletion of specific bacteria, and enrichment of bacterial virulence factors. CONCLUSIONS: We show that genetic risk may have a role in early risk stratification in the care of IBD patients and propose that expression of virulence factors in a dysbiotic microbiome may contribute to pathogenesis in IBD.

12.
Am J Hum Genet ; 101(5): 700-715, 2017 Nov 02.
Article in English | MEDLINE | ID: mdl-29100084

ABSTRACT

Short tandem repeats (STRs) are hyper-mutable sequences in the human genome. They are often used in forensics and population genetics and are also the underlying cause of many genetic diseases. There are challenges associated with accurately determining the length polymorphism of STR loci in the genome by next-generation sequencing (NGS). In particular, accurate detection of pathological STR expansion is limited by the sequence read length during whole-genome analysis. We developed TREDPARSE, a software package that incorporates various cues from read alignment and paired-end distance distribution, as well as a sequence stutter model, in a probabilistic framework to infer repeat sizes for genetic loci, and we used this software to infer repeat sizes for 30 known disease loci. Using simulated data, we show that TREDPARSE outperforms other available software. We sampled the full genome sequences of 12,632 individuals to an average read depth of approximately 30× to 40× with Illumina HiSeq X. We identified 138 individuals with risk alleles at 15 STR disease loci. We validated a representative subset of the samples (n = 19) by Sanger and by Oxford Nanopore sequencing. Additionally, we validated the STR calls against known allele sizes in a set of GeT-RM reference cell-line materials (n = 6). Several STR loci that are entirely guanine or cytosines (G or C) have insufficient read evidence for inference and therefore could not be assayed precisely by TREDPARSE. TREDPARSE extends the limit of STR size detection beyond the physical sequence read length. This extension is critical because many of the disease risk cutoffs are close to or beyond the short sequence read length of 100 to 150 bases.


Subject(s)
Genome, Human/genetics , Microsatellite Repeats/genetics , Adolescent , Adult , Alleles , Child , Female , Genetics, Population/methods , High-Throughput Nucleotide Sequencing/methods , Humans , Male , Middle Aged , Polymorphism, Genetic/genetics , Sequence Analysis, DNA/methods , Software
13.
Proc Natl Acad Sci U S A ; 114(30): 8059-8064, 2017 07 25.
Article in English | MEDLINE | ID: mdl-28674023

ABSTRACT

The HLA gene complex on human chromosome 6 is one of the most polymorphic regions in the human genome and contributes in large part to the diversity of the immune system. Accurate typing of HLA genes with short-read sequencing data has historically been difficult due to the sequence similarity between the polymorphic alleles. Here, we introduce an algorithm, xHLA, that iteratively refines the mapping results at the amino acid level to achieve 99-100% four-digit typing accuracy for both class I and II HLA genes, taking only [Formula: see text]3 min to process a 30× whole-genome BAM file on a desktop computer.


Subject(s)
Histocompatibility Testing/methods , Algorithms , Benchmarking , Humans
14.
Cell Metab ; 25(5): 1054-1062.e5, 2017 May 02.
Article in English | MEDLINE | ID: mdl-28467925

ABSTRACT

The presence of advanced fibrosis in nonalcoholic fatty liver disease (NAFLD) is the most important predictor of liver mortality. There are limited data on the diagnostic accuracy of gut microbiota-derived signature for predicting the presence of advanced fibrosis. In this prospective study, we characterized the gut microbiome compositions using whole-genome shotgun sequencing of DNA extracted from stool samples. This study included 86 uniquely well-characterized patients with biopsy-proven NAFLD, of which 72 had mild/moderate (stage 0-2 fibrosis) NAFLD, and 14 had advanced fibrosis (stage 3 or 4 fibrosis). We identified a set of 40 features (p < 0.006), which included 37 bacterial species that were used to construct a Random Forest classifier model to distinguish mild/moderate NAFLD from advanced fibrosis. The model had a robust diagnostic accuracy (AUC 0.936) for detecting advanced fibrosis. This study provides preliminary evidence for a fecal-microbiome-derived metagenomic signature to detect advanced fibrosis in NAFLD.


Subject(s)
Bacteria/isolation & purification , Gastrointestinal Microbiome , Liver Cirrhosis/microbiology , Non-alcoholic Fatty Liver Disease/microbiology , Adult , Aged , Bacteria/genetics , Feces/microbiology , Female , Humans , Liver Cirrhosis/diagnosis , Male , Metagenomics/methods , Middle Aged , Non-alcoholic Fatty Liver Disease/diagnosis , Prognosis , Prospective Studies
15.
Cell Stem Cell ; 20(4): 505-517.e6, 2017 04 06.
Article in English | MEDLINE | ID: mdl-28388429

ABSTRACT

Induced pluripotent stem cells (iPSCs) show variable methylation patterns between lines, some of which reflect aberrant differences relative to embryonic stem cells (ESCs). To examine whether this aberrant methylation results from genetic variation or non-genetic mechanisms, we generated human iPSCs from monozygotic twins to investigate how genetic background, clone, and passage number contribute. We found that aberrantly methylated CpGs are enriched in regulatory regions associated with MYC protein motifs and affect gene expression. We classified differentially methylated CpGs as being associated with genetic and/or non-genetic factors (clone and passage), and we found that aberrant methylation preferentially occurs at CpGs associated with clone-specific effects. We further found that clone-specific effects play a strong role in recurrent aberrant methylation at specific CpG sites across different studies. Our results argue that a non-genetic biological mechanism underlies aberrant methylation in iPSCs and that it is likely based on a probabilistic process involving MYC that takes place during or shortly after reprogramming.


Subject(s)
DNA Methylation/genetics , Induced Pluripotent Stem Cells/metabolism , Nucleotide Motifs/genetics , Proto-Oncogene Proteins c-myc/metabolism , Clone Cells , CpG Islands/genetics , Fibroblasts/metabolism , Gene Expression Regulation , Genetic Variation , Genome-Wide Association Study , Humans , Sequence Analysis, RNA , Transcription Factors/metabolism , Twins, Monozygotic/genetics
16.
Cell Stem Cell ; 20(4): 533-546.e7, 2017 04 06.
Article in English | MEDLINE | ID: mdl-28388430

ABSTRACT

In this study, we used whole-genome sequencing and gene expression profiling of 215 human induced pluripotent stem cell (iPSC) lines from different donors to identify genetic variants associated with RNA expression for 5,746 genes. We were able to predict causal variants for these expression quantitative trait loci (eQTLs) that disrupt transcription factor binding and validated a subset of them experimentally. We also identified copy-number variant (CNV) eQTLs, including some that appear to affect gene expression by altering the copy number of intergenic regulatory regions. In addition, we were able to identify effects on gene expression of rare genic CNVs and regulatory single-nucleotide variants and found that reactivation of gene expression on the X chromosome depends on gene chromosomal position. Our work highlights the value of iPSCs for genetic association analyses and provides a unique resource for investigating the genetic regulation of gene expression in pluripotent cells.


Subject(s)
Gene Expression Profiling/methods , Gene Expression Regulation , Genetic Variation , Induced Pluripotent Stem Cells/metabolism , Binding Sites/genetics , Cellular Reprogramming/genetics , Chromosomes, Human, X/genetics , DNA Copy Number Variations/genetics , Genetic Heterogeneity , Humans , Molecular Sequence Annotation , Quantitative Trait Loci/genetics , Regulatory Sequences, Nucleic Acid/genetics , Transcription Factors/metabolism
17.
Nat Genet ; 49(4): 568-578, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28263315

ABSTRACT

Genetic factors modifying the blood metabolome have been investigated through genome-wide association studies (GWAS) of common genetic variants and through exome sequencing. We conducted a whole-genome sequencing study of common, low-frequency and rare variants to associate genetic variations with blood metabolite levels using comprehensive metabolite profiling in 1,960 adults. We focused the analysis on 644 metabolites with consistent levels across three longitudinal data collections. Genetic sequence variations at 101 loci were associated with the levels of 246 (38%) metabolites (P ≤ 1.9 × 10-11). We identified 113 (10.7%) among 1,054 unrelated individuals in the cohort who carried heterozygous rare variants likely influencing the function of 17 genes. Thirteen of the 17 genes are associated with inborn errors of metabolism or other pediatric genetic conditions. This study extends the map of loci influencing the metabolome and highlights the importance of heterozygous rare variants in determining abnormal blood metabolic phenotypes in adults.


Subject(s)
Genetic Predisposition to Disease/genetics , Genetic Variation/genetics , Metabolome/genetics , Adult , Aged , Blood , Exome/genetics , Female , Genome-Wide Association Study/methods , Humans , Male , Middle Aged , Phenotype , Quantitative Trait Loci
18.
PLoS Pathog ; 13(3): e1006292, 2017 03.
Article in English | MEDLINE | ID: mdl-28328962

ABSTRACT

The characterization of the blood virome is important for the safety of blood-derived transfusion products, and for the identification of emerging pathogens. We explored non-human sequence data from whole-genome sequencing of blood from 8,240 individuals, none of whom were ascertained for any infectious disease. Viral sequences were extracted from the pool of sequence reads that did not map to the human reference genome. Analyses sifted through close to 1 Petabyte of sequence data and performed 0.5 trillion similarity searches. With a lower bound for identification of 2 viral genomes/100,000 cells, we mapped sequences to 94 different viruses, including sequences from 19 human DNA viruses, proviruses and RNA viruses (herpesviruses, anelloviruses, papillomaviruses, three polyomaviruses, adenovirus, HIV, HTLV, hepatitis B, hepatitis C, parvovirus B19, and influenza virus) in 42% of the study participants. Of possible relevance to transfusion medicine, we identified Merkel cell polyomavirus in 49 individuals, papillomavirus in blood of 13 individuals, parvovirus B19 in 6 individuals, and the presence of herpesvirus 8 in 3 individuals. The presence of DNA sequences from two RNA viruses was unexpected: Hepatitis C virus is revealing of an integration event, while the influenza virus sequence resulted from immunization with a DNA vaccine. Age, sex and ancestry contributed significantly to the prevalence of infection. The remaining 75 viruses mostly reflect extensive contamination of commercial reagents and from the environment. These technical problems represent a major challenge for the identification of novel human pathogens. Increasing availability of human whole-genome sequences will contribute substantial amounts of data on the composition of the normal and pathogenic human blood virome. Distinguishing contaminants from real human viruses is challenging.


Subject(s)
Blood/virology , Virus Diseases/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , DNA, Viral/blood , Female , Humans , Infant , Male , Middle Aged , Prevalence , Young Adult
19.
Proc Natl Acad Sci U S A ; 113(42): 11901-11906, 2016 10 18.
Article in English | MEDLINE | ID: mdl-27702888

ABSTRACT

We report on the sequencing of 10,545 human genomes at 30×-40× coverage with an emphasis on quality metrics and novel variant and sequence discovery. We find that 84% of an individual human genome can be sequenced confidently. This high-confidence region includes 91.5% of exon sequence and 95.2% of known pathogenic variant positions. We present the distribution of over 150 million single-nucleotide variants in the coding and noncoding genome. Each newly sequenced genome contributes an average of 8,579 novel variants. In addition, each genome carries on average 0.7 Mb of sequence that is not found in the main build of the hg38 reference genome. The density of this catalog of variation allowed us to construct high-resolution profiles that define genomic sites that are highly intolerant of genetic variation. These results indicate that the data generated by deep genome sequencing is of the quality necessary for clinical use.


Subject(s)
Genome, Human , Genomics , Whole Genome Sequencing , Chromosome Mapping , Computational Biology/methods , Databases, Nucleic Acid , Genetic Predisposition to Disease , Genetic Variation , Genomics/methods , Humans , Open Reading Frames , Polymorphism, Single Nucleotide , Reproducibility of Results , Untranslated Regions
20.
Sci Rep ; 6: 31731, 2016 08 25.
Article in English | MEDLINE | ID: mdl-27558918

ABSTRACT

As reports on possible associations between microbes and the host increase in number, more meaningful interpretations of this information require an ability to compare data sets across studies. This is dependent upon standardization of workflows to ensure comparability both within and between studies. Here we propose the standard use of an alternate collection and stabilization method that would facilitate such comparisons. The DNA Genotek OMNIgene∙Gut Stool Microbiome Kit was compared to the currently accepted community standard of freezing to store human stool samples prior to whole genome sequencing (WGS) for microbiome studies. This stabilization and collection device allows for ambient temperature storage, automation, and ease of shipping/transfer of samples. The device permitted the same data reproducibility as with frozen samples, and yielded higher recovery of nucleic acids. Collection and stabilization of stool microbiome samples with the DNA Genotek collection device, combined with our extraction and WGS, provides a robust, reproducible workflow that enables standardized global collection, storage, and analysis of stool for microbiome studies.


Subject(s)
Microbiota , Specimen Handling/methods , Temperature , Algorithms , Cohort Studies , DNA, Bacterial/analysis , DNA, Bacterial/chemistry , Feces , Freezing , Humans , Linear Models , Models, Statistical , Nucleic Acids/chemistry , Open Reading Frames , Quality Control , Reproducibility of Results , Whole Genome Sequencing
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