Publications by authors named "Vaidehi Jobanputra"

63 Publications

Metastatic Pediatric Sclerosing Epithelioid Fibrosarcoma.

Cold Spring Harb Mol Case Stud 2021 Aug 6. Epub 2021 Aug 6.

University of Alabama at Birmingham;

Sclerosing epithelioid fibrosarcoma (SEF) is a rare and aggressive soft tissue sarcoma thought to originate in fibroblasts of the tissues comprising tendons, ligaments and muscles. Minimally responsive to conventional cytotoxic chemotherapies, greater than 50% of SEF patients experience local recurrence and/or metastatic disease. SEF is most commonly discovered in middle-aged and elderly adults, but also rarely in children. A common gene fusion occurring between the EWSR1 and CREB3L1 genes has been observed in 80-90% of SEF cases. We describe here the youngest SEF patient reported to date (a 3-year-old Caucasian male) who presented with numerous bony and lung metastases. Additionally, we perform a comprehensive literature review of all SEF-related articles published since the disease was first characterized. Finally, we describe the generation of an SEF primary cell line, the first such culture to be reported. The patient described here experienced persistent disease progression despite aggressive treatment including multiple resections, radiotherapy and numerous chemotherapies and targeted therapeutics. Untreated and locally recurrent tumor and metastatic tissue were sequenced by whole genome, whole exome, and deep transcriptome next generation sequencing with comparison to a patient-matched normal blood sample. Consistent across all sequencing analyses was the disease-defining EWSR1-CREB3L1 fusion as a single feature consensus. We provide an analysis of our genomic findings and discuss potential therapeutic strategies for SEF.
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http://dx.doi.org/10.1101/mcs.a006093DOI Listing
August 2021

Clinical interpretation of whole-genome and whole-transcriptome sequencing for precision oncology.

Semin Cancer Biol 2021 Jul 10. Epub 2021 Jul 10.

Institute for Computational Biomedicine, Weill Cornell Medicine, New York, United States; Englander Institute for Precision Medicine, Weill Cornell Medicine, New York, United States. Electronic address:

Whole-genome sequencing either alone or in combination with whole-transcriptome sequencing has started to be used to analyze clinical tumor samples to improve diagnosis, provide risk stratification, and select patient-specific therapies. Compared with current genomic testing strategies, largely focused on small number of genes tested individually or targeted panels, whole-genome and transcriptome sequencing (WGTS) provides novel opportunities to identify and report a potentially much larger number of actionable alterations with diagnostic, prognostic, and/or predictive impact. Such alterations include point mutations, indels, copy- number aberrations and structural variants, but also germline variants, fusion genes, noncoding alterations and mutational signatures. Nevertheless, these comprehensive tests are accompanied by many challenges ranging from the extent and diversity of sequence alterations detected by these methods to the complexity and limited existing standardization in interpreting them. We describe the challenges of WGTS interpretation and the opportunities with comprehensive genomic testing.
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http://dx.doi.org/10.1016/j.semcancer.2021.07.003DOI Listing
July 2021

Clinical utility of whole-genome sequencing in precision oncology.

Semin Cancer Biol 2021 Jun 25. Epub 2021 Jun 25.

NIHR Oxford Biomedical Research Centre and Department of Oncology, University of Oxford, Oxford, United Kingdom. Electronic address:

Precision diagnostics is one of the two pillars of precision medicine. Sequencing efforts in the past decade have firmly established cancer as a primarily genetically driven disease. This concept is supported by therapeutic successes aimed at particular pathways that are perturbed by specific driver mutations in protein-coding domains and reflected in three recent FDA tissue agnostic cancer drug approvals. In addition, there is increasing evidence from studies that interrogate the entire genome by whole-genome sequencing that acquired global and complex genomic aberrations including those in non-coding regions of the genome might also reflect clinical outcome. After addressing technical, logistical, financial and ethical challenges, national initiatives now aim to introduce clinical whole-genome sequencing into real-world diagnostics as a rational and potentially cost-effective tool for response prediction in cancer and to identify patients who would benefit most from 'expensive' targeted therapies and recruitment into clinical trials. However, so far, this has not been accompanied by a systematic and prospective evaluation of the clinical utility of whole-genome sequencing within clinical trials of uniformly treated patients of defined clinical outcome. This approach would also greatly facilitate novel predictive biomarker discovery and validation, ultimately reducing size and duration of clinical trials and cost of drug development. This manuscript is the third in a series of three to review and critically appraise the potential and challenges of clinical whole-genome sequencing in solid tumors and hematological malignancies.
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http://dx.doi.org/10.1016/j.semcancer.2021.06.018DOI Listing
June 2021

Analytical demands to use whole-genome sequencing in precision oncology.

Semin Cancer Biol 2021 Jun 10. Epub 2021 Jun 10.

MLL Munich Leukemia Laboratory, Munich, Germany. Electronic address:

Interrogating the tumor genome in its entirety by whole-genome sequencing (WGS) offers an unprecedented insight into the biology and pathogenesis of cancer, with potential impact on diagnostics, prognostication and therapy selection. WGS is able to detect sequence as well as structural variants and thereby combines central domains of cytogenetics and molecular genetics. Given the potential of WGS in directing targeted therapeutics and clinical decision-making, we envision a gradual transition of the method from research to clinical routine. This review is one out of three within this issue aimed at facilitating this effort, by discussing in-depth analytical validation, clinical interpretation and clinical utility of WGS. The review highlights the requirements for implementing, validating and maintaining a clinical WGS pipeline to obtain high-quality patient-specific data in accordance with the local regulatory landscape. Every step of the WGS pipeline, which includes DNA extraction, library preparation, sequencing, bioinformatics analysis, and data storage, is considered with respect to its logistics, necessities, potential pitfalls, and the required quality management. WGS is likely to drive clinical diagnostics and patient care forward, if requirements and challenges of the technique are recognized and met.
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http://dx.doi.org/10.1016/j.semcancer.2021.06.009DOI Listing
June 2021

GenomeDiver: a platform for phenotype-guided medical genomic diagnosis.

Genet Med 2021 Oct 10;23(10):1998-2002. Epub 2021 Jun 10.

Division of Genetics, Department of Pediatrics, Children's Hospital at Montefiore, Bronx, NY, USA.

Purpose: Making a diagnosis from clinical genomic sequencing requires well-structured phenotypic data to guide genotype interpretation. A patient's phenotypic features can be documented using the Human Phenotype Ontology (HPO), generating terms used to prioritize genes potentially causing the patient's disease. We have developed GenomeDiver to provide a user interface for clinicians that allows more effective collaboration with the clinical diagnostic laboratory, with the goal of improving the success of the diagnostic process.

Methods: GenomeDiver uses genomic data to prompt reverse phenotyping of patients undergoing genetic testing, enriching the amount and quality of structured phenotype data for the diagnostic laboratory, and helping clinicians to explore and flag diseases potentially causing their patient's presentation.

Results: We show how GenomeDiver communicates the clinician's informed insights to the diagnostic lab in the form of HPO terms for interpretation of genomic sequencing data. We describe our user-driven design process, the engineering of the software for efficiency, security and portability, and examples of the performance of GenomeDiver using genomic testing data.

Conclusion: GenomeDiver is a first step in a new approach to genomic diagnostics that enhances laboratory-clinician interactions, with the goal of directly engaging clinicians to improve the outcome of genomic diagnostic testing.
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http://dx.doi.org/10.1038/s41436-021-01219-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8488006PMC
October 2021

De novo TRIM8 variants impair its protein localization to nuclear bodies and cause developmental delay, epilepsy, and focal segmental glomerulosclerosis.

Am J Hum Genet 2021 02 27;108(2):357-367. Epub 2021 Jan 27.

Division of Pediatric Neurology and Developmental Medicine, Duke University Medical Center, Durham, NC 27710, USA.

Focal segmental glomerulosclerosis (FSGS) is the main pathology underlying steroid-resistant nephrotic syndrome (SRNS) and a leading cause of chronic kidney disease. Monogenic forms of pediatric SRNS are predominantly caused by recessive mutations, while the contribution of de novo variants (DNVs) to this trait is poorly understood. Using exome sequencing (ES) in a proband with FSGS/SRNS, developmental delay, and epilepsy, we discovered a nonsense DNV in TRIM8, which encodes the E3 ubiquitin ligase tripartite motif containing 8. To establish whether TRIM8 variants represent a cause of FSGS, we aggregated exome/genome-sequencing data for 2,501 pediatric FSGS/SRNS-affected individuals and 48,556 control subjects, detecting eight heterozygous TRIM8 truncating variants in affected subjects but none in control subjects (p = 3.28 × 10). In all six cases with available parental DNA, we demonstrated de novo inheritance (p = 2.21 × 10). Reverse phenotyping revealed neurodevelopmental disease in all eight families. We next analyzed ES from 9,067 individuals with epilepsy, yielding three additional families with truncating TRIM8 variants. Clinical review revealed FSGS in all. All TRIM8 variants cause protein truncation clustering within the last exon between residues 390 and 487 of the 551 amino acid protein, indicating a correlation between this syndrome and loss of the TRIM8 C-terminal region. Wild-type TRIM8 overexpressed in immortalized human podocytes and neuronal cells localized to nuclear bodies, while constructs harboring patient-specific variants mislocalized diffusely to the nucleoplasm. Co-localization studies demonstrated that Gemini and Cajal bodies frequently abut a TRIM8 nuclear body. Truncating TRIM8 DNVs cause a neuro-renal syndrome via aberrant TRIM8 localization, implicating nuclear bodies in FSGS and developmental brain disease.
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http://dx.doi.org/10.1016/j.ajhg.2021.01.008DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7895901PMC
February 2021

The NYCKidSeq project: study protocol for a randomized controlled trial incorporating genomics into the clinical care of diverse New York City children.

Trials 2021 Jan 14;22(1):56. Epub 2021 Jan 14.

Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.

Background: Increasingly, genomics is informing clinical practice, but challenges remain for medical professionals lacking genetics expertise, and in access to and clinical utility of genomic testing for minority and underrepresented populations. The latter is a particularly pernicious problem due to the historical lack of inclusion of racially and ethnically diverse populations in genomic research and genomic medicine. A further challenge is the rapidly changing landscape of genetic tests and considerations of cost, interpretation, and diagnostic yield for emerging modalities like whole-genome sequencing.

Methods: The NYCKidSeq project is a randomized controlled trial recruiting 1130 children and young adults predominantly from Harlem and the Bronx with suspected genetic disorders in three disease categories: neurologic, cardiovascular, and immunologic. Two clinical genetic tests will be performed for each participant, either proband, duo, or trio whole-genome sequencing (depending on sample availability) and proband targeted gene panels. Clinical utility, cost, and diagnostic yield of both testing modalities will be assessed. This study will evaluate the use of a novel, digital platform (GUÍA) to digitize the return of genomic results experience and improve participant understanding for English- and Spanish-speaking families. Surveys will collect data at three study visits: baseline (0 months), result disclosure visit (ROR1, + 3 months), and follow-up visit (ROR2, + 9 months). Outcomes will assess parental understanding of and attitudes toward receiving genomic results for their child and behavioral, psychological, and social impact of results. We will also conduct a pilot study to assess a digital tool called GenomeDiver designed to enhance communication between clinicians and genetic testing labs. We will evaluate GenomeDiver's ability to increase the diagnostic yield compared to standard practices, improve clinician's ability to perform targeted reverse phenotyping, and increase the efficiency of genetic testing lab personnel.

Discussion: The NYCKidSeq project will contribute to the innovations and best practices in communicating genomic test results to diverse populations. This work will inform strategies for implementing genomic medicine in health systems serving diverse populations using methods that are clinically useful, technologically savvy, culturally sensitive, and ethically sound.

Trial Registration: ClinicalTrials.gov NCT03738098 . Registered on November 13, 2018 Trial Sponsor: Icahn School of Medicine at Mount Sinai Contact Name: Eimear Kenny, PhD (Principal Investigator) Address: Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Pl., Box 1003, New York, NY 10029 Email: [email protected]
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http://dx.doi.org/10.1186/s13063-020-04953-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7807444PMC
January 2021

Clinical utility of genomic sequencing: a measurement toolkit.

NPJ Genom Med 2020 Dec 15;5(1):56. Epub 2020 Dec 15.

Stanford Medicine, Stanford, CA, USA.

Whole-genome sequencing (WGS) is positioned to become one of the most robust strategies for achieving timely diagnosis of rare genomic diseases. Despite its favorable diagnostic performance compared to conventional testing strategies, routine use and reimbursement of WGS are hampered by inconsistencies in the definition and measurement of clinical utility. For example, what constitutes clinical utility for WGS varies by stakeholder's perspective (physicians, patients, families, insurance companies, health-care organizations, and society), clinical context (prenatal, pediatric, critical care, adult medicine), and test purpose (diagnosis, screening, treatment selection). A rapidly evolving technology landscape and challenges associated with robust comparative study design in the context of rare disease further impede progress in this area of empiric research. To address this challenge, an expert working group of the Medical Genome Initiative was formed. Following a consensus-based process, we align with a broad definition of clinical utility and propose a conceptually-grounded and empirically-guided measurement toolkit focused on four domains of utility: diagnostic thinking efficacy, therapeutic efficacy, patient outcome efficacy, and societal efficacy. For each domain of utility, we offer specific indicators and measurement strategies. While we focus on diagnostic applications of WGS for rare germline diseases, this toolkit offers a flexible framework for best practices around measuring clinical utility for a range of WGS applications. While we expect this toolkit to evolve over time, it provides a resource for laboratories, clinicians, and researchers looking to characterize the value of WGS beyond the laboratory.
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http://dx.doi.org/10.1038/s41525-020-00164-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7738524PMC
December 2020

Compound heterozygous inheritance of two novel COQ2 variants results in familial coenzyme Q deficiency.

Orphanet J Rare Dis 2020 11 13;15(1):320. Epub 2020 Nov 13.

Edward S. Harkness Eye Institute, Columbia University Irving Medical Center, New York, NY, USA.

Background: Primary coenzyme Q10 deficiency is a rare disease that results in diverse and variable clinical manifestations. Nephropathy, myopathy and neurologic involvement are commonly associated, however retinopathy has also been observed with certain pathogenic variants of genes in the coenzyme Q biosynthesis pathway. In this report, we describe a novel presentation of the disease that includes nephropathy and retinopathy without neurological involvement, and which is the result of a compound heterozygous state arising from the inheritance of two recessive potentially pathogenic variants, previously not described.

Materials And Methods: Retrospective report, with complete ophthalmic examination, multimodal imaging, electroretinography, and whole exome sequencing performed on a family with three affected siblings.

Results: We show that affected individuals in the described family inherited two heterozygous variants of the COQ2 gene, resulting in a frameshift variant in one allele, and a predicted deleterious missense variant in the second allele (c.288dupC,p.(Ala97Argfs*56) and c.376C > G,p.(Arg126Gly) respectively). Electroretinography results were consistent with rod-cone dystrophy in the affected individuals. All affected individuals in the family exhibited the characteristic retinopathy as well as end-stage nephropathy, without evidence of any neurological involvement.

Conclusions: We identified two novel compound heterozygous variants of the COQ2 gene that result in primary coenzyme Q deficiency. Targeted sequencing of coenzyme Q biosynthetic pathway genes may be useful in diagnosing oculorenal clinical presentations syndromes not explained by more well known syndromes (e.g., Senior-Loken and Bardet-Biedl syndromes).
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http://dx.doi.org/10.1186/s13023-020-01600-8DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7662744PMC
November 2020

Detection of Copy Number Variants by Short Multiply Aggregated Sequence Homologies.

J Mol Diagn 2020 12 23;22(12):1476-1481. Epub 2020 Oct 23.

Cold Spring Harbor Laboratory, Cold Spring Harbor, New York. Electronic address:

Chromosomal microarray testing is indicated for patients with diagnoses including unexplained developmental delay or intellectual disability, autism spectrum disorders, and multiple congenital anomalies. The short multiply aggregated sequence homologies (SMASH) genomic assay is a novel next-generation sequencing technology that performs copy number analysis at resolution similar to high-coverage whole genome sequencing but requires far less capacity. We benchmarked the performance of SMASH on a panel of genomic DNAs containing known copy number variants (CNVs). SMASH was able to detect pathogenic copy number variants of ≥10 kb in 77 of 77 samples. No pathogenic events were seen in 32 of 32 controls, indicating 100% sensitivity and specificity for detecting pathogenic CNVs >10 kb. Repeatability (interassay precision) and reproducibility (intra-assay precision) were assessed with 13 samples and showed perfect concordance. We also established that SMASH had a limit of detection of 20% for detection of large mosaic CNVs. Finally, we analyzed seven blinded specimens by SMASH analysis and successfully identified all pathogenic events. These results establish the efficacy of the SMASH genomic assay as a clinical test for the detection of pathogenic copy number variants at a resolution comparable to chromosomal microarray analysis.
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http://dx.doi.org/10.1016/j.jmoldx.2020.09.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7722526PMC
December 2020

Best practices for the analytical validation of clinical whole-genome sequencing intended for the diagnosis of germline disease.

NPJ Genom Med 2020 23;5:47. Epub 2020 Oct 23.

Broad Institute of MIT and Harvard, Cambridge, MA USA.

Whole-genome sequencing (WGS) has shown promise in becoming a first-tier diagnostic test for patients with rare genetic disorders; however, standards addressing the definition and deployment practice of a best-in-class test are lacking. To address these gaps, the Medical Genome Initiative, a consortium of leading healthcare and research organizations in the US and Canada, was formed to expand access to high-quality clinical WGS by publishing best practices. Here, we present consensus recommendations on clinical WGS analytical validation for the diagnosis of individuals with suspected germline disease with a focus on test development, upfront considerations for test design, test validation practices, and metrics to monitor test performance. This work also provides insight into the current state of WGS testing at each member institution, including the utilization of reference and other standards across sites. Importantly, members of this initiative strongly believe that clinical WGS is an appropriate first-tier test for patients with rare genetic disorders, and at minimum is ready to replace chromosomal microarray analysis and whole-exome sequencing. The recommendations presented here should reduce the burden on laboratories introducing WGS into clinical practice, and support safe and effective WGS testing for diagnosis of germline disease.
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http://dx.doi.org/10.1038/s41525-020-00154-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7585436PMC
October 2020

Variant Classification Concordance using the ACMG-AMP Variant Interpretation Guidelines across Nine Genomic Implementation Research Studies.

Am J Hum Genet 2020 11 26;107(5):932-941. Epub 2020 Oct 26.

Department of Pathology, Massachusetts General Hospital, Harvard Medical School and Laboratory for Molecular Medicine, Partners HealthCare Personalized Medicine, Boston, MA 02139, USA.

Harmonization of variant pathogenicity classification across laboratories is important for advancing clinical genomics. The two CLIA-accredited Electronic Medical Record and Genomics Network sequencing centers and the six CLIA-accredited laboratories and one research laboratory performing genome or exome sequencing in the Clinical Sequencing Evidence-Generating Research Consortium collaborated to explore current sources of discordance in classification. Eight laboratories each submitted 20 classified variants in the ACMG secondary finding v.2.0 genes. After removing duplicates, each of the 158 variants was annotated and independently classified by two additional laboratories using the ACMG-AMP guidelines. Overall concordance across three laboratories was assessed and discordant variants were reviewed via teleconference and email. The submitted variant set included 28 P/LP variants, 96 VUS, and 34 LB/B variants, mostly in cancer (40%) and cardiac (27%) risk genes. Eighty-six (54%) variants reached complete five-category (i.e., P, LP, VUS, LB, B) concordance, and 17 (11%) had a discordance that could affect clinical recommendations (P/LP versus VUS/LB/B). 21% and 63% of variants submitted as P and LP, respectively, were discordant with VUS. Of the 54 originally discordant variants that underwent further review, 32 reached agreement, for a post-review concordance rate of 84% (118/140 variants). This project provides an updated estimate of variant concordance, identifies considerations for LP classified variants, and highlights ongoing sources of discordance. Continued and increased sharing of variant classifications and evidence across laboratories, and the ongoing work of ClinGen to provide general as well as gene- and disease-specific guidance, will lead to continued increases in concordance.
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http://dx.doi.org/10.1016/j.ajhg.2020.09.011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7675005PMC
November 2020

The Medical Genome Initiative: moving whole-genome sequencing for rare disease diagnosis to the clinic.

Genome Med 2020 05 27;12(1):48. Epub 2020 May 27.

Broad Institute of MIT and Harvard, Cambridge, MA, USA.

Clinical whole-genome sequencing (WGS) offers clear diagnostic benefits for patients with rare disease. However, there are barriers to its widespread adoption, including a lack of standards for clinical practice. The Medical Genome Initiative consortium was formed to provide practical guidance and support the development of standards for the use of clinical WGS.
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http://dx.doi.org/10.1186/s13073-020-00748-zDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7254704PMC
May 2020

Deep whole-genome sequencing of 3 cancer cell lines on 2 sequencing platforms.

Sci Rep 2019 12 13;9(1):19123. Epub 2019 Dec 13.

New York Genome Center, New York, NY, 10013, USA.

To test the performance of a new sequencing platform, develop an updated somatic calling pipeline and establish a reference for future benchmarking experiments, we performed whole-genome sequencing of 3 common cancer cell lines (COLO-829, HCC-1143 and HCC-1187) along with their matched normal cell lines to great sequencing depths (up to 278x coverage) on both Illumina HiSeqX and NovaSeq sequencing instruments. Somatic calling was generally consistent between the two platforms despite minor differences at the read level. We designed and implemented a novel pipeline for the analysis of tumor-normal samples, using multiple variant callers. We show that coupled with a high-confidence filtering strategy, the use of combination of tools improves the accuracy of somatic variant calling. We also demonstrate the utility of the dataset by creating an artificial purity ladder to evaluate the somatic pipeline and benchmark methods for estimating purity and ploidy from tumor-normal pairs. The data and results of the pipeline are made accessible to the cancer genomics community.
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http://dx.doi.org/10.1038/s41598-019-55636-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6911065PMC
December 2019

Identification of targetable BRAF ΔN486_P490 variant by whole-genome sequencing leading to dabrafenib-induced remission of a -mutant pancreatic adenocarcinoma.

Cold Spring Harb Mol Case Stud 2019 12 13;5(6). Epub 2019 Dec 13.

Stony Brook Cancer Center, Stony Brook Medicine, Stony Brook, New York 11794, USA.

The tumor genome of a patient with advanced pancreatic cancer was sequenced to identify potential therapeutic targetable mutations after standard of care failed to produce any significant overall response. Matched tumor-normal whole-genome sequencing revealed somatic mutations in , , , and a focal deletion of The variant was an in-frame deletion mutation (ΔN486_P490), which had been previously demonstrated to be a kinase-activating alteration in the BRAF kinase domain. Working with the Novartis patient assistance program allowed us to treat the patient with the BRAF inhibitor, dabrafenib. The patient's overall clinical condition improved dramatically with dabrafenib. Levels of serum tumor marker dropped immediately after treatment, and a subsequent CT scan revealed a significant decrease in the size of both primary and metastatic lesions. The dabrafenib-induced remission lasted for 6 mo. Preclinical studies published concurrently with the patient's treatment showed that the BRAF in-frame mutation (ΔNVTAP) induces oncogenic activation by a mechanism distinct from that induced by V600E, and that this difference dictates the responsiveness to different BRAF inhibitors. This study describes a dramatic instance of how high-level genomic technology and analysis was necessary and sufficient to identify a clinically logical treatment option that was then utilized and shown to be of clinical value for this individual.
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http://dx.doi.org/10.1101/mcs.a004424DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6913137PMC
December 2019

Sequencing and curation strategies for identifying candidate glioblastoma treatments.

BMC Med Genomics 2019 04 25;12(1):56. Epub 2019 Apr 25.

Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY, 10065, USA.

Background: Prompted by the revolution in high-throughput sequencing and its potential impact for treating cancer patients, we initiated a clinical research study to compare the ability of different sequencing assays and analysis methods to analyze glioblastoma tumors and generate real-time potential treatment options for physicians.

Methods: A consortium of seven institutions in New York City enrolled 30 patients with glioblastoma and performed tumor whole genome sequencing (WGS) and RNA sequencing (RNA-seq; collectively WGS/RNA-seq); 20 of these patients were also analyzed with independent targeted panel sequencing. We also compared results of expert manual annotations with those from an automated annotation system, Watson Genomic Analysis (WGA), to assess the reliability and time required to identify potentially relevant pharmacologic interventions.

Results: WGS/RNAseq identified more potentially actionable clinical results than targeted panels in 90% of cases, with an average of 16-fold more unique potentially actionable variants identified per individual; 84 clinically actionable calls were made using WGS/RNA-seq that were not identified by panels. Expert annotation and WGA had good agreement on identifying variants [mean sensitivity = 0.71, SD = 0.18 and positive predictive value (PPV) = 0.80, SD = 0.20] and drug targets when the same variants were called (mean sensitivity = 0.74, SD = 0.34 and PPV = 0.79, SD = 0.23) across patients. Clinicians used the information to modify their treatment plan 10% of the time.

Conclusion: These results present the first comprehensive comparison of technical and machine augmented analysis of targeted panel and WGS/RNA-seq to identify potential cancer treatments.
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http://dx.doi.org/10.1186/s12920-019-0500-0DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6485090PMC
April 2019

High-resolution genomic alterations in Barrett's metaplasia of patients who progress to esophageal dysplasia and adenocarcinoma.

Int J Cancer 2019 11 2;145(10):2754-2766. Epub 2019 May 2.

Department of Pathology and Cell Biology, Columbia University Irving Medical Center (CUIMC), New York, NY.

The main risk factor for esophageal dysplasia and adenocarcinoma (DAC) is Barrett's esophagus (BE), characterized by intestinal metaplasia. The critical genomic mechanisms that lead to progression of nondysplastic BE to DAC remain poorly understood and require analyses of longitudinal patient cohorts and high-resolution assays. We tested BE tissues from 74 patients, including 42 nonprogressors from two separate groups of 21 patients each and 32 progressors (16 in a longitudinal cohort before DAC/preprogression-BE and 16 with temporally concurrent but spatially separate DAC/concurrent-BE). We interrogated genome-wide somatic copy number alterations (SCNAs) at the exon level with high-resolution SNP arrays in DNA from formalin-fixed samples histologically confirmed as nondysplastic BE. The most frequent abnormalities were SCNAs involving FHIT exon 5, CDKN2A/B or both in 88% longitudinal BE progressors to DAC vs. 24% in both nonprogressor groups (p = 0.0004). Deletions in other genomic regions were found in 56% of preprogression-BE but only in one nonprogressor-BE (p = 0.0004). SCNAs involving FHIT exon 5 and CDKN2A/B were also frequently detected in BE temporally concurrent with DAC. TP53 losses were detected in concurrent-BE but not earlier in preprogression-BE tissues of patients who developed DAC. CDKN2A/p16 immunohistochemistry showed significant loss of expression in BE of progressors vs. nonprogressors, supporting the genomic data. Our data suggest a role for CDKN2A/B and FHIT in early progression of BE to dysplasia and adenocarcinoma that warrants future mechanistic research. Alterations in CDKN2A/B and FHIT by high-resolution assays may serve as biomarkers of increased risk of progression to DAC when detected in BE tissues.
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http://dx.doi.org/10.1002/ijc.32351DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6750991PMC
November 2019

Whole-exome sequencing in the evaluation of fetal structural anomalies: a prospective cohort study.

Lancet 2019 02 31;393(10173):758-767. Epub 2019 Jan 31.

Institute for Genomic Medicine, Columbia University Medical Center, New York, NY, USA; Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Columbia University Medical Center, New York, NY, USA. Electronic address:

Background: Identification of chromosomal aneuploidies and copy number variants that are associated with fetal structural anomalies has substantial value. Although whole-exome sequencing (WES) has been applied to case series of a few selected prenatal cases, its value in routine clinical settings has not been prospectively assessed in a large unselected cohort of fetuses with structural anomalies. We therefore aimed to determine the incremental diagnostic yield (ie, the added value) of WES following uninformative results of standard investigations with karyotype testing and chromosomal microarray in an unselected cohort of sequential pregnancies showing fetal structural anomalies.

Methods: In this prospective cohort study, the parents of fetuses who were found to have a structural anomaly in a prenatal ultrasound were screened for possible participation in the study. These participants were predominantly identified in or were referred to the Columbia University Carmen and John Thain Center for Prenatal Pediatrics (New York, NY, USA). Fetuses with confirmed aneuploidy or a causal pathogenic copy number variant were excluded from WES analyses. By use of WES of the fetuses and parents (parent-fetus trios), we identified genetic variants that indicated an underlying cause (diagnostic genetic variants) and genetic variants that met the criteria of bioinformatic signatures that had previously been described to be significantly enriched among diagnostic genetic variants.

Findings: Between April 24, 2015, and April 19, 2017, 517 sequentially identified pregnant women found to have fetuses with a structural anomaly were screened for their eligibility for inclusion in our study. 71 (14%) couples declined testing, 87 (17%) trios were missing at least one DNA sample (from either parent or the fetus), 69 (13%) trios had a clinically relevant abnormal karyotype or chromosomal microarray finding, 51 (10%) couples did not consent to WES or withdrew consent, and five (1%) samples were not of good enough quality for analysis. DNA samples from 234 (45%) eligible trios were therefore used for analysis of the primary outcome. By use of trio sequence data, we identified diagnostic genetic variants in 24 (10%) families. Mutations with bioinformatic signatures that were indicative of pathogenicity but with insufficient evidence to be considered diagnostic were also evaluated; 46 (20%) of the 234 fetuses assessed were found to have such signatures.

Interpretation: Our analysis of WES data in a prospective cohort of unselected fetuses with structural anomalies shows the value added by WES following the use of routine genetic tests. Our findings suggest that, in cases of fetal anomalies in which assessment with karyotype testing and chromosomal microarray fail to determine the underlying cause of a structural anomaly, WES can add clinically relevant information that could assist current management of a pregnancy. The unique challenges of WES-based prenatal diagnostics require analysis by a multidisciplinary team of perinatal practitioners and laboratory specialists.

Funding: Institute for Genomic Medicine (Columbia University Irving Medical Center).
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http://dx.doi.org/10.1016/S0140-6736(18)32042-7DOI Listing
February 2019

Prenatal Diagnosis by Whole Exome Sequencing in Fetuses with Ultrasound Abnormalities.

Methods Mol Biol 2019 ;1885:267-285

Molecular Diagnostics, New York Genome Center, New York, NY, USA.

Whole-exome sequencing (WES) has been used as a standard of care for postnatal diagnosis in the clinical setting in the past few years for children and adults with undiagnosed disease. Many rare disorders have been diagnosed through WES, which is less expensive than the traditional serial genetic testing where patients had previously spent years on an uninformative diagnostic odyssey. Seeking a diagnosis often entails enduring time consuming, and sometimes invasive procedures which may be associated with medical risks that are stressful for families and impose a heavy burden on the health-care system. However, the use of WES is considered impractical in the prenatal and neonatal testing period because of the technical and computational challenges of performing genomic sequencing from small amounts of genetic material, and the need for faster turnaround time (TAT) than the current 6-8 weeks TAT provided by most clinical labs offering postnatal testing. With the rapidly evolving methods of sequence analysis, there are clinical challenges such as the constantly increasing number of genes being identified which are not yet fully phenotypically characterized, especially when ascertained prenatally or neonatally before all the clinical features may be evident. Despite these challenges, there are many clinical benefits to acquiring genomic information in the prenatal and neonatal period. These include superior prognostic information which allows for prenatal planning of mode of delivery and hospital for delivery and optimized neonatal management. We have developed a clinical WES assay using small amounts of DNA with a TAT of 10 days for use in the prenatal or neonatal setting. This test is used to detect small nucleotide variants and indels in fetuses and neonates with structural abnormalities.
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http://dx.doi.org/10.1007/978-1-4939-8889-1_18DOI Listing
June 2019

Analytical Validation of Clinical Whole-Genome and Transcriptome Sequencing of Patient-Derived Tumors for Reporting Targetable Variants in Cancer.

J Mol Diagn 2018 11 21;20(6):822-835. Epub 2018 Aug 21.

New York Genome Center, New York, New York; Columbia University Medical Center, Columbia University, New York, New York. Electronic address:

We developed and validated a clinical whole-genome and transcriptome sequencing (WGTS) assay that provides a comprehensive genomic profile of a patient's tumor. The ability to fully capture the mappable genome with sufficient sequencing coverage to precisely call DNA somatic single nucleotide variants, insertions/deletions, copy number variants, structural variants, and RNA gene fusions was analyzed. New York State's Department of Health next-generation DNA sequencing guidelines were expanded for establishing performance validation applicable to whole-genome and transcriptome sequencing. Whole-genome sequencing laboratory protocols were validated for the Illumina HiSeq X Ten platform and RNA sequencing for Illumina HiSeq2500 platform for fresh or frozen and formalin-fixed, paraffin-embedded tumor samples. Various bioinformatics tools were also tested, and CIs for sensitivity and specificity thresholds in calling clinically significant somatic aberrations were determined. The validation was performed on a set of 125 tumor normal pairs. RNA sequencing was performed to call fusions and to confirm the DNA variants or exonic alterations. Here, we present our results and WGTS standards for variant allele frequency, reproducibility, analytical sensitivity, and present limit of detection analysis for single nucleotide variant calling, copy number identification, and structural variants. We show that The New York Genome Center WGTS clinical assay can provide a comprehensive patient variant discovery approach suitable for directed oncologic therapeutic applications.
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http://dx.doi.org/10.1016/j.jmoldx.2018.06.007DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6198246PMC
November 2018

Phenotypic expansion and progression of SPATA7-associated retinitis pigmentosa.

Doc Ophthalmol 2018 04 6;136(2):125-133. Epub 2018 Feb 6.

Jonas Children's Vision Care, and Bernard & Shirlee Brown Glaucoma Laboratory, New York, NY, USA.

Purpose: To report an unusual phenotype of retinitis pigmentosa (RP) caused by compound heterozygous mutations in SPATA7, and describe the progression over a two year follow-up period.

Methods: Retrospective case study.

Results: A 63-year-old man with a long history of nyctalopia, progressive visual field constriction, and a recent subacute decrease in visual acuity of the left eye presented for evaluation of a suspected retinal degeneration. Multimodal retinal imaging and functional assessment with full-field electroretinogram suggested a severe rod-cone dysfunction masquerading as a choroideremia-like phenotype. A vitreous opacity was found to explain recent changes in the left eye and a 25-guage vitrectomy and membrane peel was performed, yielding no change in visual acuity. Whole-exome sequencing revealed compound heterozygous variants in SPATA7 that were predicted to be pathogenic.

Conclusions: Compound heterozygous c.1100A > G, p.(Y367C) and c.1102_1103delCT, p.(L368Efs*4) variants in SPATA7 manifest as an unusual RP phenotype in this case, showing extensive choroidal sclerosis and retinal pigment epithelium (RPE) atrophy with evidence of progression over two years on multimodal imaging.
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http://dx.doi.org/10.1007/s10633-018-9626-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6015729PMC
April 2018

Whole Genome Sequencing-Based Discovery of Structural Variants in Glioblastoma.

Methods Mol Biol 2018 ;1741:1-29

New York Genome Center, New York, NY, USA.

Next-generation DNA sequencing (NGS) technologies are currently being applied in both research and clinical settings for the understanding and management of disease. The goal is to use high-throughput sequencing to identify specific variants that drive tumorigenesis within each individual's tumor genomic profile. The significance of copy number and structural variants in glioblastoma makes it essential to broaden the search beyond oncogenic single nucleotide variants toward whole genome profiles of genetic aberrations that may contribute to disease progression. The heterogeneity of glioblastoma and its variability of cancer driver mutations necessitate a more robust examination of a patient's tumor genome. Here, we present patient whole genome sequencing (WGS) information to identify oncogenic structural variants that may contribute to glioblastoma pathogenesis. We provide WGS protocols and bioinformatics approaches to identify copy number and structural variations in 41 glioblastoma patient samples. We present how WGS can identify structural diversity within glioblastoma samples. We specifically show how to apply current bioinformatics tools to detect EGFR variants and other structural aberrations from DNA whole genome sequencing and how to validate those variants within the laboratory. These comprehensive WGS protocols can provide additional information directing more precise therapeutic options in the treatment of glioblastoma.
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http://dx.doi.org/10.1007/978-1-4939-7659-1_1DOI Listing
December 2018

Clinical whole exome sequencing from dried blood spot identifies novel genetic defect underlying asparagine synthetase deficiency.

Clin Case Rep 2018 01 15;6(1):200-205. Epub 2017 Dec 15.

Molecular Diagnostics New York Genome Center New York city New York.

We add two novel variants to the existing mutation spectrum of ASNS gene. Loss of ASNS function should be suspected in newborns presenting with congenital microcephaly, intellectual disability, progressive cerebral atrophy, and intractable seizures. Acquisition and sequencing of stored newborn blood spot can be a valuable option when no biological samples are available from a deceased child.
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http://dx.doi.org/10.1002/ccr3.1284DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5771929PMC
January 2018

Whole-Exome Sequencing in Adults With Chronic Kidney Disease: A Pilot Study.

Ann Intern Med 2018 01 5;168(2):100-109. Epub 2017 Dec 5.

From Columbia University, New York, New York; VU University Medical Center, Amsterdam, the Netherlands; Nephrology Associates, Newark, Delaware; Krysiewicza Children's Hospital, Poznań, Poland; Poznań University of Medical Sciences and Center for Medical Genetics GENESIS, Poznań, Poland; IRCCS Giannina Gaslini Children's Hospital, Genova, Italy; IRCCS San Raffaele Scientific Institute, Milan, Italy; New York University School of Medicine, New York, New York; University of Texas Southwestern Medical Center, Dallas, Texas; and French Institute of Health and Medical Research (INSERM) U1163, Paris Descartes-Sorbonne Paris Cité University, Imagine Institute, and Necker Hospital, Paris, France.

Background: The utility of whole-exome sequencing (WES) for the diagnosis and management of adult-onset constitutional disorders has not been adequately studied. Genetic diagnostics may be advantageous in adults with chronic kidney disease (CKD), in whom the cause of kidney failure often remains unknown.

Objective: To study the diagnostic utility of WES in a selected referral population of adults with CKD.

Design: Observational cohort.

Setting: A major academic medical center.

Patients: 92 adults with CKD of unknown cause or familial nephropathy or hypertension.

Measurements: The diagnostic yield of WES and its potential effect on clinical management.

Results: Whole-exome sequencing provided a diagnosis in 22 of 92 patients (24%), including 9 probands with CKD of unknown cause and encompassing 13 distinct genetic disorders. Among these, loss-of-function mutations were identified in PARN in 2 probands with tubulointerstitial fibrosis. PARN mutations have been implicated in a short telomere syndrome characterized by lung, bone marrow, and liver fibrosis; these findings extend the phenotype of PARN mutations to renal fibrosis. In addition, review of the American College of Medical Genetics actionable genes identified a pathogenic BRCA2 mutation in a proband who was diagnosed with breast cancer on follow-up. The results affected clinical management in most identified cases, including initiation of targeted surveillance, familial screening to guide donor selection for transplantation, and changes in therapy.

Limitation: The small sample size and recruitment at a tertiary care academic center limit generalizability of findings among the broader CKD population.

Conclusion: Whole-exome sequencing identified diagnostic mutations in a substantial number of adults with CKD of many causes. Further study of the utility of WES in the evaluation and care of patients with CKD in additional settings is warranted.

Primary Funding Source: New York State Empire Clinical Research Investigator Program, Renal Research Institute, and National Human Genome Research Institute of the National Institutes of Health.
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http://dx.doi.org/10.7326/M17-1319DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5947852PMC
January 2018

Impact of Receiving Secondary Results from Genomic Research: A 12-Month Longitudinal Study.

J Genet Couns 2018 06 22;27(3):709-722. Epub 2017 Nov 22.

Department of Pediatrics, Columbia University Medical Center, New York, NY, USA.

The impact of returning secondary results from exome sequencing (ES) on patients/participants is important to understand as ES is increasingly utilized in clinical care and research. Participants were recruited from studies using ES and were separated into two arms: 107 who had ES and were offered the choice to learn secondary results (ES group) and 85 who had not yet had ES (No ES group). Questionnaires were administered at baseline and 1 and 12 months, following results disclosure (ES group) or enrollment (No ES group). While the majority (65%) elected to learn all results following pre-test counseling, it was reduced from the 76% who indicated a desire for all results at baseline. Thirty-seven percent received results associated with an increased personal disease risk. There were no differences in changes in any of the psychological and social measures from baseline to post-results disclosure between the ES and No ES groups. Receiving a wide range of secondary findings appeared to have little measurable impact on most participants. The experience of learning secondary results may be related to participants' previous experiences with genetics, as well as the genetic counseling provided. Future research with a more diverse, genetically naïve group, as well as scalable methods of delivery, is needed.
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http://dx.doi.org/10.1007/s10897-017-0172-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5945295PMC
June 2018

Pancreatic intraductal tubulopapillary neoplasm is genetically distinct from intraductal papillary mucinous neoplasm and ductal adenocarcinoma.

Mod Pathol 2017 12 4;30(12):1760-1772. Epub 2017 Aug 4.

Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY, USA.

Intraductal tubulopapillary neoplasm is a relatively recently described member of the pancreatic intraductal neoplasm family. The more common member of this family, intraductal papillary mucinous neoplasm, often carries genetic alterations typical of pancreatic infiltrating ductal adenocarcinoma (KRAS, TP53, and CDKN2A) but additionally has mutations in GNAS and RNF43 genes. However, the genetic characteristics of intraductal tubulopapillary neoplasm have not been well characterized. Twenty-two intraductal tubulopapillary neoplasms were analyzed by either targeted next-generation sequencing, which enabled the identification of sequence mutations, copy number alterations, and selected structural rearrangements involving all targeted (≥300) genes, or whole-exome sequencing. Three of these intraductal tubulopapillary neoplasms were also subjected to whole-genome sequencing. All intraductal tubulopapillary neoplasms revealed the characteristic histologic (cellular intraductal nodules of back-to-back tubular glands lined by predominantly cuboidal cells with atypical nuclei and no obvious intracellular mucin) and immunohistochemical (immunolabeled with MUC1 and MUC6 but were negative for MUC2 and MUC5AC) features. By genomic analyses, there was loss of CDKN2A in 5/20 (25%) of these cases. However, the majority of the previously reported intraductal papillary mucinous neoplasm-related alterations were absent. Moreover, in contrast to most ductal neoplasms of the pancreas, MAP-kinase pathway was not involved. In fact, 2/22 (9%) of intraductal tubulopapillary neoplasms did not reveal any mutations in the tested genes. However, certain chromatin remodeling genes (MLL1, MLL2, MLL3, BAP1, PBRM1, EED, and ATRX) were found to be mutated in 7/22 (32%) of intraductal tubulopapillary neoplasms and 27% harbored phosphatidylinositol 3-kinase (PI3K) pathway (PIK3CA, PIK3CB, INPP4A, and PTEN) mutations. In addition, 4/18 (18%) of intraductal tubulopapillary neoplasms had FGFR2 fusions (FGFR2-CEP55, FGFR2-SASS6, DISP1-FGFR2, FGFR2-TXLNA, and FGFR2-VCL) and 1/18 (5.5%) had STRN-ALK fusion. Intraductal tubulopapillary neoplasm is a distinct clinicopathologic entity in the pancreas. Although its intraductal nature and some clinicopathologic features resemble those of intraductal papillary mucinous neoplasm, our results suggest that intraductal tubulopapillary neoplasm has distinguishing genetic characteristics. Some of these mutated genes are potentially targetable. Future functional studies will be needed to determine the consequences of these gene alterations.
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http://dx.doi.org/10.1038/modpathol.2017.60DOI Listing
December 2017

Comparing sequencing assays and human-machine analyses in actionable genomics for glioblastoma.

Neurol Genet 2017 Aug 11;3(4):e164. Epub 2017 Jul 11.

New York Genome Center (K.O.W., M.O.F., N.R., A.-K.E., B.-J.C., K.A., M.S., V.V., E.A.B., J.L.M.V., M.C.Z., V.J., R.B.D.); IBM Thomas J. Watson Research Center (T.K., K.R., F.U., R.N., E.B., L.P., A.K.R.); Columbia University Medical Center (J.N.B., A.B.L., P.C., V.J.); Memorial Sloan-Kettering Cancer Center (C.G.), New York, NY; IBM Watson Health (S.H., V.V.M.), Boca Raton, FL; Laboratory of Molecular Neuro-Oncology (M.O.F., R.B.D.), and Howard Hughes Medical Institute (R.B.D.), The Rockefeller University, New York, NY. B.-J.C. is currently affiliated with Google, New York, NY. V.V. is currently affiliated with 23andMe, Inc., Mountain View, CA. E.A.B. is currently affiliated with Max Planck Institute of Immunobiology and Epigenetics, Freiburg, Germany.

Objective: To analyze a glioblastoma tumor specimen with 3 different platforms and compare potentially actionable calls from each.

Methods: Tumor DNA was analyzed by a commercial targeted panel. In addition, tumor-normal DNA was analyzed by whole-genome sequencing (WGS) and tumor RNA was analyzed by RNA sequencing (RNA-seq). The WGS and RNA-seq data were analyzed by a team of bioinformaticians and cancer oncologists, and separately by IBM Watson Genomic Analytics (WGA), an automated system for prioritizing somatic variants and identifying drugs.

Results: More variants were identified by WGS/RNA analysis than by targeted panels. WGA completed a comparable analysis in a fraction of the time required by the human analysts.

Conclusions: The development of an effective human-machine interface in the analysis of deep cancer genomic datasets may provide potentially clinically actionable calls for individual patients in a more timely and efficient manner than currently possible.

Clinicaltrialsgov Identifier: NCT02725684.
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http://dx.doi.org/10.1212/NXG.0000000000000164DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5506390PMC
August 2017

Indel variant analysis of short-read sequencing data with Scalpel.

Nat Protoc 2016 Dec 17;11(12):2529-2548. Epub 2016 Nov 17.

Simons Center for Quantitative Biology, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, USA.

As the second most common type of variation in the human genome, insertions and deletions (indels) have been linked to many diseases, but the discovery of indels of more than a few bases in size from short-read sequencing data remains challenging. Scalpel (http://scalpel.sourceforge.net) is an open-source software for reliable indel detection based on the microassembly technique. It has been successfully used to discover mutations in novel candidate genes for autism, and it is extensively used in other large-scale studies of human diseases. This protocol gives an overview of the algorithm and describes how to use Scalpel to perform highly accurate indel calling from whole-genome and whole-exome sequencing data. We provide detailed instructions for an exemplary family-based de novo study, but we also characterize the other two supported modes of operation: single-sample and somatic analysis. Indel normalization, visualization and annotation of the mutations are also illustrated. Using a standard server, indel discovery and characterization in the exonic regions of the example sequencing data can be completed in ∼5 h after read mapping.
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http://dx.doi.org/10.1038/nprot.2016.150DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5507611PMC
December 2016
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