scholarly journals A small gene sequencing panel realises a high diagnostic rate in patients with congenital nystagmus following basic phenotyping

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Luke O’Gorman ◽  
Chelsea S. Norman ◽  
Luke Michaels ◽  
Tutte Newall ◽  
Andrew H. Crosby ◽  
...  
Keyword(s):  
Diagnostic Yield ◽  
Congenital Nystagmus ◽  
High Diagnostic Yield ◽  
Infantile Nystagmus ◽  
Targeted Ngs ◽  
Causal Variants ◽  
Next Generation Sequencing Ngs ◽  
Changing Role ◽  
Generation Sequencing

Abstract Nystagmus is a disorder of uncontrolled eye movement and can occur as an isolated trait (idiopathic INS, IINS) or as part of multisystem disorders such as albinism, significant visual disorders or neurological disease. Eighty-one unrelated patients with nystagmus underwent routine ocular phenotyping using commonly available phenotyping methods and were grouped into four sub-cohorts according to the level of phenotyping information gained and their findings. DNA was extracted and sequenced using a broad utility next generation sequencing (NGS) gene panel. A clinical subpanel of genes for nystagmus/albinism was utilised and likely causal variants were prioritised according to methods currently employed by clinical diagnostic laboratories. We determine the likely underlying genetic cause for 43.2% of participants with similar yields regardless of prior phenotyping. This study demonstrates that a diagnostic workflow combining basic ocular phenotyping and a clinically available targeted NGS panel, can provide a high diagnostic yield for patients with infantile nystagmus, enabling access to disease specific management at a young age and reducing the need for multiple costly, often invasive tests. By describing diagnostic yield for groups of patients with incomplete phenotyping data, it also permits the subsequent design of ‘real-world’ diagnostic workflows and illustrates the changing role of genetic testing in modern diagnostic workflows for heterogeneous ophthalmic disorders.

scholarly journals Progressive Myoclonus Epilepsies

2021 ◽  
Vol 7 (6) ◽  
pp. e641
Author(s):  
Laura Canafoglia ◽  
Silvana Franceschetti ◽  
Antonio Gambardella ◽  
Pasquale Striano ◽  
Anna Teresa Giallonardo ◽  
...  
Keyword(s):  
Late Onset ◽  
Diagnostic Yield ◽  
Homozygosity Mapping ◽  
Genetic Origin ◽  
Pathogenic Variants ◽  
Whole Exome ◽  
Progressive Ataxia ◽  
Targeted Ngs ◽  
Next Generation Sequencing Ngs ◽  
Generation Sequencing

Background and ObjectivesTo assess the current diagnostic yield of genetic testing for the progressive myoclonus epilepsies (PMEs) of an Italian series described in 2014 where Unverricht-Lundborg and Lafora diseases accounted for ∼50% of the cohort.MethodsOf 47/165 unrelated patients with PME of indeterminate genetic origin, 38 underwent new molecular evaluations. Various next-generation sequencing (NGS) techniques were applied including gene panel analysis (n = 7) and/or whole-exome sequencing (WES) (WES singleton n = 29, WES trio n = 7, and WES sibling n = 4). In 1 family, homozygosity mapping was followed by targeted NGS. Clinically, the patients were grouped in 4 phenotypic categories: “Unverricht-Lundborg disease-like PME,” “late-onset PME,” “PME plus developmental delay,” and “PME plus dementia.”ResultsSixteen of 38 (42%) unrelated patients reached a positive diagnosis, increasing the overall proportion of solved families in the total series from 72% to 82%. Likely pathogenic variants were identified in NEU1 (2 families), CERS1 (1 family), and in 13 nonfamilial patients in KCNC1 (3), DHDDS (3), SACS, CACNA2D2, STUB1, AFG3L2, CLN6, NAXE, and CHD2. Across the different phenotypic categories, the diagnostic rate was similar, and the same gene could be found in different phenotypic categories.DiscussionThe application of NGS technology to unsolved patients with PME has revealed a collection of very rare genetic causes. Pathogenic variants were detected in both established PME genes and in genes not previously associated with PME, but with progressive ataxia or with developmental encephalopathies. With a diagnostic yield >80%, PME is one of the best genetically defined epilepsy syndromes.

scholarly journals CSF3R T618I, SETBP1 G870S, SRSF2 P95H, and ASXL1 Q780* tetramutation co-contribute to myeloblast transformation in a chronic neutrophilic leukemia

2021 ◽  
Author(s):  
Yi Qian ◽  
Yan Chen ◽  
Xiaoming Li
Keyword(s):  
Alpha Interferon ◽  
Past Medical History ◽  
Variant Allele Frequency ◽  
Significant Past Medical History ◽  
Chronic Neutrophilic Leukemia ◽  
Hypercellular Marrow ◽  
Next Generation Sequencing Ngs ◽  
Generation Sequencing ◽  
Stat Pathway

AbstractChronic neutrophilic leukemia (CNL) is a rare but serious myeloid malignancy. In a review of reported cases for WHO-defined CNL, CSF3R mutation is found in about 90% cases and confirmed as the molecular basis of CNL. Concurrent mutations are observed in CSF3R-mutated CNL patients, including ASXL1, SETBP1, SRSF2, JAK2, CALR, TET2, NRAS, U2AF1, and CBL. Both ASXL1 and SETBP1 mutations in CNL have been associated with a poor prognosis, whereas, SRSF2 mutation was undetermined. Our patient was a 77-year-old man and had no significant past medical history and symptoms with leukocytosis. Bone marrow (BM) aspirate and biopsy revealed a markedly hypercellular marrow with prominent left-shifted granulopoiesis. Next-generation sequencing (NGS) of DNA from the BM aspirate of a panel of 28 genes, known to be pathogenic in MDS/MPN, detected mutations in CSF3R, SETBP1, and SRSF2, and a diagnosis of CNL was made. The patient did not use a JAK-STAT pathway inhibitor (ruxolitinib) but started on hydroxyurea and alpha-interferon and developed pruritus after 4 months of diagnosis and nasal hemorrhage 1 month later. Then, the patient was diagnosed with CNL with AML transformation and developed intracranial hemorrhage and died. We repeated NGS and found that three additional mutations were detected: ASXL1, PRKDC, MYOM2; variant allele frequency (VAF) of the prior mutations in CSF3R, SETBP1, and SRSF2 increased. The concurrence of CSF3RT618I, ASXL1, SETBP1, and SRSF2 mutation may be a mutationally detrimental combination and contribute to disease progression and AML transformation, as well as the nonspecific treatment of hydroxyurea and alpha-interferon, but the significance and role of PRKDC and MYOM2 mutations were not undetermined.

High diagnostic yield of syndromic intellectual disability by targeted next-generation sequencing

2016 ◽  
Vol 54 (2) ◽  
pp. 87-92 ◽  
Author(s):  
Francisco Martínez ◽  
Alfonso Caro-Llopis ◽  
Mónica Roselló ◽  
Silvestre Oltra ◽  
Sonia Mayo ◽  
...  
Keyword(s):  
Intellectual Disability ◽  
Next Generation Sequencing ◽  
Diagnostic Yield ◽  
Next Generation ◽  
Targeted Next Generation Sequencing ◽  
High Diagnostic Yield ◽  
Generation Sequencing

scholarly journals The ICR96 exon CNV validation series: a resource for orthogonal assessment of exon CNV calling in NGS data

2017 ◽  
Vol 2 ◽  
pp. 35 ◽  
Author(s):  
Shazia Mahamdallie ◽  
Elise Ruark ◽  
Shawn Yost ◽  
Emma Ramsay ◽  
Imran Uddin ◽  
...  
Keyword(s):  
Sequencing Data ◽  
Targeted Next Generation Sequencing ◽  
Negative Results ◽  
Targeted Ngs ◽  
Predisposition Genes ◽  
Next Generation Sequencing Ngs ◽  
Ngs Data ◽  
Validation Series ◽  
Generation Sequencing ◽  
Dependent Probe

Detection of deletions and duplications of whole exons (exon CNVs) is a key requirement of genetic testing. Accurate detection of this variant type has proved very challenging in targeted next-generation sequencing (NGS) data, particularly if only a single exon is involved. Many different NGS exon CNV calling methods have been developed over the last five years. Such methods are usually evaluated using simulated and/or in-house data due to a lack of publicly-available datasets with orthogonally generated results. This hinders tool comparisons, transparency and reproducibility. To provide a community resource for assessment of exon CNV calling methods in targeted NGS data, we here present the ICR96 exon CNV validation series. The dataset includes high-quality sequencing data from a targeted NGS assay (the TruSight Cancer Panel) together with Multiplex Ligation-dependent Probe Amplification (MLPA) results for 96 independent samples. 66 samples contain at least one validated exon CNV and 30 samples have validated negative results for exon CNVs in 26 genes. The dataset includes 46 exon CNVs in BRCA1, BRCA2, TP53, MLH1, MSH2, MSH6, PMS2, EPCAM or PTEN, giving excellent representation of the cancer predisposition genes most frequently tested in clinical practice. Moreover, the validated exon CNVs include 25 single exon CNVs, the most difficult type of exon CNV to detect. The FASTQ files for the ICR96 exon CNV validation series can be accessed through the European-Genome phenome Archive (EGA) under the accession number EGAS00001002428.

Role of Ancillary Techniques in Biliary Cytopathology Specimens

2019 ◽  
Vol 64 (1-2) ◽  
pp. 175-181 ◽  
Author(s):  
Lester Layfield
Keyword(s):  
Mutational Analysis ◽  
Diagnostic Sensitivity ◽  
Individual Gene ◽  
Duct Systems ◽  
Brushing Cytology ◽  
Standard Of Practice ◽  
Next Generation Sequencing Ngs ◽  
Generation Sequencing

Biliary brushing cytology has become the standard of practice for the investigation of strictures of the biliary and pancreatic duct systems. The methodology however has a limitation in that it has low diagnostic sensitivity when only cytologic evaluation is used. A number of testing methodologies have been applied to brushing specimens in an attempt to improve overall sensitivity without loss of specificity. These have included DNA ploidy analysis, immunocytochemistry, individual gene mutational analysis, fluorescence in-situ hybridization (FISH), and next generation sequencing (NGS). Currently, FISH coupled with routine cytology appears to be the method of choice for improving diagnostic sensitivity. NGS shows significant promise for improvement of diagnostic sensitivity.

scholarly journals Next Generation Sequencing Identifies Five Novel Mutations in Lebanese Patients with Bardet–Biedl and Usher Syndromes

Genes ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 1047 ◽  
Author(s):  
Lama Jaffal ◽  
Wissam H Joumaa ◽  
Alexandre Assi ◽  
Charles Helou ◽  
George Cherfan ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Usher Syndrome ◽  
Bioinformatic Analysis ◽  
Next Generation ◽  
Novel Mutations ◽  
Pathogenic Variants ◽  
Whole Exome ◽  
Targeted Ngs ◽  
Next Generation Sequencing Ngs ◽  
Generation Sequencing

Aim: To identify disease-causing mutations in four Lebanese families: three families with Bardet–Biedl and one family with Usher syndrome (BBS and USH respectively), using next generation sequencing (NGS). Methods: We applied targeted NGS in two families and whole exome sequencing (WES) in two other families. Pathogenicity of candidate mutations was evaluated according to frequency, conservation, in silico prediction tools, segregation with disease, and compatibility with inheritance pattern. The presence of pathogenic variants was confirmed via Sanger sequencing followed by segregation analysis. Results: Most likely disease-causing mutations were identified in all included patients. In BBS patients, we found (M1): c.2258A > T, p. (Glu753Val) in BBS9, (M2): c.68T > C; p. (Leu23Pro) in ARL6, (M3): c.265_266delTT; p. (Leu89Valfs*11) and (M4): c.880T > G; p. (Tyr294Asp) in BBS12. A previously known variant (M5): c.551A > G; p. (Asp184Ser) was also detected in BBS5. In the USH patient, we found (M6): c.188A > C, p. (Tyr63Ser) in CLRN1. M2, M3, M4, and M6 were novel. All of the candidate mutations were shown to be likely disease-causing through our bioinformatic analysis. They also segregated with the corresponding phenotype in available family members. Conclusion: This study expanded the mutational spectrum and showed the genetic diversity of BBS and USH. It also spotlighted the efficiency of NGS techniques in revealing mutations underlying clinically and genetically heterogeneous disorders.

scholarly journals New Challenges in Tumor Mutation Heterogeneity in Advanced Ovarian Cancer by a Targeted Next-Generation Sequencing (NGS) Approach

Cells ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 584 ◽  
Author(s):  
Marica Garziera ◽  
Rossana Roncato ◽  
Marcella Montico ◽  
Elena De Mattia ◽  
Sara Gagno ◽  
...  
Keyword(s):  
Ovarian Cancer ◽  
Next Generation Sequencing ◽  
Residual Disease ◽  
Advanced Ovarian Cancer ◽  
Genetic Profile ◽  
Next Generation ◽  
Platinum Based Chemotherapy ◽  
Targeted Ngs ◽  
Next Generation Sequencing Ngs ◽  
Generation Sequencing

Next-generation sequencing (NGS) technology has advanced knowledge of the genomic landscape of ovarian cancer, leading to an innovative molecular classification of the disease. However, patient survival and response to platinum-based treatments are still not predictable based on the tumor genetic profile. This retrospective study characterized the repertoire of somatic mutations in advanced ovarian cancer to identify tumor genetic markers predictive of platinum chemo-resistance and prognosis. Using targeted NGS, 79 primary advanced (III–IV stage, tumor grade G2-3) ovarian cancer tumors, including 64 high-grade serous ovarian cancers (HGSOCs), were screened with a 26 cancer-genes panel. Patients, enrolled between 1995 and 2011, underwent primary debulking surgery (PDS) with optimal residual disease (RD < 1 cm) and platinum-based chemotherapy as first-line treatment. We found a heterogeneous mutational landscape in some uncommon ovarian histotypes and in HGSOC tumor samples with relevance in predicting platinum sensitivity. In particular, we identified a poor prognostic signature in patients with HGSOC harboring concurrent mutations in two driver actionable genes of the panel. The tumor heterogeneity described, sheds light on the translational potential of targeted NGS approach for the identification of subgroups of patients with distinct therapeutic vulnerabilities, that are modulated by the specific mutational profile expressed by the ovarian tumor.

scholarly journals NGS and phenotypic ontology-based approaches increase the diagnostic yield in syndromic retinal diseases

2021 ◽  
Author(s):  
I. Perea-Romero ◽  
F. Blanco-Kelly ◽  
I. Sanchez-Navarro ◽  
I. Lorda-Sanchez ◽  
S. Tahsin-Swafiri ◽  
...  
Keyword(s):  
Exome Sequencing ◽  
Diagnostic Yield ◽  
A Priori ◽  
Retinal Diseases ◽  
Human Phenotype ◽  
Whole Exome ◽  
Next Generation Sequencing Ngs ◽  
Generation Sequencing ◽  
Clinical Category ◽  
Selection Of

AbstractSyndromic retinal diseases (SRDs) are a group of complex inherited systemic disorders, with challenging molecular underpinnings and clinical management. Our main goal is to improve clinical and molecular SRDs diagnosis, by applying a structured phenotypic ontology and next-generation sequencing (NGS)-based pipelines. A prospective and retrospective cohort study was performed on 100 probands with an a priori diagnosis of non-Usher SRDs, using available clinical data, including Human Phenotype Ontology annotation, and further classification into seven clinical categories (ciliopathies, specific syndromes and five others). Retrospective molecular diagnosis was assessed using different molecular and bioinformatic methods depending on availability. Subsequently, uncharacterized probands were prospectively screened using other NGS approaches to extend the number of analyzed genes. After phenotypic classification, ciliopathies were the most common SRD (35%). A global characterization rate of 52% was obtained, with six cases incompletely characterized for a gene that partially explained the phenotype. An improved characterization rate was achieved addressing prospective cases (83%) and well-recognizable syndrome (62%) subgroups. The 27% of the fully characterized cases were reclassified into a different clinical category after identification of the disease-causing gene. Clinical-exome sequencing is the most appropriate first-tier approach for prospective cases, whereas whole-exome sequencing and bioinformatic reanalysis increases the diagnosis of uncharacterized retrospective cases to 45%, mostly those with unspecific symptoms. Our study describes a comprehensive approach to SRDs in daily clinical practice and the importance of thorough clinical assessment and selection of the most appropriate molecular test to be used to solve these complex cases and elucidate novel associations.

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