Whole-genome Sequencing of Common Salivary Gland Carcinomas: Subtype Restricted and Shared Genetic Alterations.

Abstract Pathogenesis of autonomous steroid secretion and adrenocortical tumorigenesis remains partially obscure. Our aim was to identify novel genetic alterations in adrenocortical adenomas (ACA) without somatic mutations in known driver genes. Whole-genome sequencing was performed on 26 ACA/blood-derived DNA pairs without driver mutations in PRKACA, GNAS and CTNNB1 genes at previous WES (ENSAT study JCEM 2016). These included 12 cortisol-producing adenomas with Cushing syndrome (CS-CPAs), 7 with mild autonomous cortisol secretion (MACS-CPAs), and 7 endocrine-inactive ACAs (EIAs). Seven adrenocortical carcinomas (ACC) were added to the cohort. We developed a bioinformatics pipeline for a comprehensive genome analysis and to reveal differences in variant distribution. Strelka, VarScan2 and ANNOVAR software and an in-house confidence score were used for variant calling and functional annotation. Combined Annotation-Dependent-Depletion (CADD) values were used to prioritize pathogenic variants. Additional focus relied on variants in pathogenically known pathways (Wnt/β-catenin, cAMP/PKA pathway). NovoBreak algorithm was applied to discover structural variations. Two hypermutated CS-CPA samples were excluded from further analysis. Using different filters, we detected variants in driver genes not observed at WES (one p.S45P in CTNNB1 and one p.R206L in PRKACA in two different CS-CPAs). In total, we report 179,830 variations (179,598 SNVs; 232 indels) throughout all samples, being more abundant in ACC (88,954) compared to ACA (CS-CPAs: 31,821; MACS-CPAs: 35,008; EIAs: 29,963). Most alterations were in intergenic (>50%), followed by intronic and ncRNA intronic regions. A total of 32 predicted pathogenic variants were found in both coding (CADD values ≥ 15) and non-coding (CADD values ≥ 5) regions. We found 3,301 possibly damaging and recurrent variants (intergenic mutations removed) (CS-CPAs: 1,463; MACS-CPAs: 1,549; EIAs: 1,268; ACC: 1,660), mostly accumulated in intronic regions. Some of these were detected in members of the Wnt/β-catenin (CS-CPAs: 6; MACS-CPAs: 2; EIA: 1) and cAMP/PKA (CS-CPAs: 6; MACS-CPAs: 7; EIA: 4) pathways (e.g. ADCY1, ADCY2, GNA13, PDE11A). We also found a slightly higher number of structural variations in EIA (3,620) and ACC (3,486) compared to CS-CPAs (977) and MACS-CPAs (2,119). In conclusion, still unrevealed genetic alterations, especially in intronic regions, may accompany early adrenal tumorigenesis and/or autonomous cortisol secretion.

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Integrated Molecular Analysis of Myelodysplastic Syndromes Using Whole Genome Sequencing

Blood ◽

10.1182/blood.v128.22.5512.5512 ◽

2016 ◽

Vol 128 (22) ◽

pp. 5512-5512

Author(s):

Yasuito Nannya ◽

Yoshida Kenichi ◽

Keisuke Kataoka ◽

Yasunobu Nagata ◽

Tetsuichi Yoshizato ◽

...

Keyword(s):

Whole Genome Sequencing ◽

Genome Sequencing ◽

Research Funding ◽

Genetic Alterations ◽

Whole Genome ◽

Structural Variations ◽

Coding Regions ◽

Molecular Events ◽

Targeted Capture ◽

Capture Sequencing

Abstract Background Myelodysplastic syndromes (MDS) are a heterogeneous group of myeloid malignancies characterized by refractory cytopenias with marrow dysplasia, which frequently progress to acute myeloid leukemia (AML). Although poorly understood in the previous era, the molecular events that underlie the pathogenesis of MDS have been intensively studied using advanced genomics in the past decade and are now fully catalogued into an array of well-defined functional pathways. However, mostly obtained through exome/targeted-capture sequencing, our knowledge about these molecular events is largely confined to those of single nucleotide variations (SNVs) and short indels, as well as arm-level copy number lesions, mostly within the coding sequences. Alterations in the non-coding regions, particularly a diversity of structural variations, in MDS genomes remain to be investigated in most part, even though the relevance of such lesions has recently been unequivocally demonstrated for other cancer types through large-scale whole genome sequencing (WGS) studies. Unfortunately, however, only a small number of MDS samples have been fully analyzes and inspected for genetic alterations using WGS. Patients and Methods In the present study, we performed an integrated, unbiased molecular study of 60 MDS cases, using whole genome sequencing (WGS) in combination with exome and transcriptome sequencing as well as methylome analysis. Paired tumor/germline DNA were obtained from patients' bone marrow and buccal smear samples. Sequencing data were analyzed using novel in-house pipelines, which were tuned to optimize detection of complex structural variations (SVs) and abnormalities in non-coding sequences. For some patients, multiple longitudinal materials were obtained along with their clinical course. Results WGS identified SNVs across the entire genome with a mean of 5.7/Mb/genome with a clear predominance of age-related C to T transitions, followed by other signatures. The spectrum of major targets of somatic mutations successfully recapitulated the previously reported one in MDS, including those involving splicing factors (SRSF2, SF3B1, U2AF1, and ZRSR2), epigenetic regulators (DNMT3A, ASXL1, TET2, BCOR, and EZH2), transcription factors (RUNX1, ETV6, and CUX1), signal transducing molecules (NRAS, KRAS, FLT3, PTPN11, CBL), and other critical molecules (TP53, NPM1, and STAG2). Moreover, other somatic variants within the coding regions were also identified that had already been reported in other human cancers but not in MDS, such as NCOR2X, MUC6, and TIAM2. The analysis of SVs unexpectedly revealed the complexity of MDS genomes. Most of the MDS genomes analyzed had a heavy burden of SVs including tandem duplications, deletions, translocations, and inversions, with a mean of 7.2/genome, which was far more than expected from conventional cytogenetics and array-based karyotyping. Complex rearrangements were common, frequently converging into particular chromosomes, suggesting multiple genetic events at a single genetic insult. Known targets of SNVs and indels were often affected by SVs, which largely escaped from conventional exome and targeted-capture sequencing, including RUNX1, TET2, FHITand other genes, suggesting that conventional platforms may substantially underestimate the frequency of alterations for some genes. Concomitant transcriptome analysis allowed to correlated abnormal splicing with somatic intronic events otherwise undetectable. Furthermore, comprehensive analysis of genomic aberrations in longitudinal samples enabled us to delineate the clonal architecture of the cellular population in MDS and their dynamics during the AML progression or clonal changes caused by AZA treatment. Conclusions Integrated molecular analysis using WGS and other platforms revealed the complexity of MDS genomes previously unexpected and reveal novel genetic alterations. Our results should help to extend our knowledge about the genomic landscape of MDS and provide novel insights into the molecular pathogenesis and clonal dynamics of MDS. Disclosures Kataoka: Kyowa Hakko Kirin: Honoraria; Boehringer Ingelheim: Honoraria; Yakult: Honoraria. Naoe:Pfizer Inc.: Research Funding; CMIC Co., Ltd.: Research Funding; Kyowa-Hakko Kirin Co.,Ltd.: Honoraria, Patents & Royalties, Research Funding; Otsuka Pharmaceutical Co.,Ltd.: Honoraria, Research Funding; Nippon Boehringer Ingelheim Co., Ltd.: Honoraria, Research Funding; Amgen Astellas BioPharma K.K.: Honoraria; TOYAMA CHEMICAL CO.,LTD.: Research Funding; Chugai Pharmaceutical Co.,LTD.: Honoraria, Patents & Royalties; Celgene K.K.: Honoraria, Research Funding; Sumitomo Dainippon Pharma Co.,Ltd.: Honoraria, Research Funding; Fujifilm Corporation: Honoraria, Patents & Royalties, Research Funding; Bristol-Myers Squibb: Honoraria; Astellas Pharma Inc.: Research Funding. Kiyoi:Celgene Corporation: Consultancy; MSD K.K.: Research Funding; Mochida Pharmaceutical Co., Ltd.: Research Funding; Nippon Boehringer Ingelheim Co., Ltd.: Research Funding; Kyowa-Hakko Kirin Co.LTD.: Research Funding; Fujifilm Corporation: Patents & Royalties, Research Funding; JCR Pharmaceutlcals Co.,Ltd.: Research Funding; Alexion Pharmaceuticals: Research Funding; Yakult Honsha Co.,Ltd.: Research Funding; Eisai Co., Ltd.: Research Funding; Chugai Pharmaceutical Co. LTD.: Research Funding; Toyama Chemikal Co.,Ltd.: Research Funding; Astellas Pharma Inc.: Consultancy, Research Funding; Phizer Japan Inc.: Research Funding; Novartis Pharma K.K.: Research Funding; Nippon Shinyaku Co., Ltd.: Research Funding; Takeda Pharmaceutical Co., Ltd.: Research Funding; Sumitomo Dainippon Pharma Co., Ltd.: Research Funding; Zenyaku Kogyo Co.LTD.: Research Funding; AlexionpharmaLLC.: Research Funding. Ogawa:Kan research institute: Consultancy, Research Funding; Takeda Pharmaceuticals: Consultancy, Research Funding; Sumitomo Dainippon Pharma: Research Funding.

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Identification of Genetic Alterations Associated with Acquired Colistin Resistance in Klebsiella pneumoniae Isogenic Strains by Whole-Genome Sequencing

Antibiotics ◽

10.3390/antibiotics9070374 ◽

2020 ◽

Vol 9 (7) ◽

pp. 374

Author(s):

Myeongjin Choi ◽

Kwan Soo Ko

Keyword(s):

Amino Acid ◽

Klebsiella Pneumoniae ◽

Whole Genome Sequencing ◽

Candidate Genes ◽

Genome Sequencing ◽

Parental Strain ◽

Genetic Alterations ◽

Amino Acid Substitutions ◽

Whole Genome ◽

Colistin Resistance

The present study was undertaken to find novel genes associated with colistin resistance in Klebsiella pneumoniae. Five colistin-resistant mutants were derived from four colistin-susceptible parental K. pneumoniae strains belonging to different clones. Whole-genome sequencing was performed for the nine K. pneumoniae strains to screen altered candidate genes. Expression levels of genes with amino acid alterations in derivative strains were determined using quantitative real-time Polymerase chain reaction (PCR). Colistin susceptibility was examined in a parental strain complemented with altered candidate genes. Overall, 13 genetic alterations were identified in five pairs of isogenic K. pneumoniae strains. Genetic alterations related to KP1_3468, including the insertion of an IS5-like element in an intergenic or coding region and amino acid substitutions, were identified in three separate derivative strains. Amino acid substitutions and deletion of PhoQ were determined in one derivative strain. With inactivation of CrrA and substituted CrrB, amino acid substitutions and deletion were identified in a repressor of galETK operon (KP1_0061) and hypothetical protein (KP1_3620), respectively. Decreased colistin susceptibility was observed in a parental strain complemented with KP1-0061, but not a KP1-3620 gene. This study demonstrated diverse genetic paths to colistin resistance in K. pneumoniae. Our results suggest that a repressor of galETK operon may play an important role in colistin resistance in K. pneumoniae.

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Whole Genome Sequencing of a Vietnamese Family from a Dioxin Contamination Hotspot Reveals Novel Variants in the Son with Undiagnosed Intellectual Disability

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15122629 ◽

2018 ◽

Vol 15 (12) ◽

pp. 2629 ◽

Cited By ~ 1

Author(s):

Dang Nguyen ◽

Hai Nguyen ◽

Thuy Nguyen ◽

Thi Nguyen ◽

Kaoru Nakano ◽

...

Keyword(s):

Intellectual Disability ◽

Whole Genome Sequencing ◽

Genome Sequencing ◽

De Novo ◽

Genetic Alterations ◽

Whole Genome ◽

Missense Mutations ◽

De Novo Mutations ◽

Bioinformatics Analyses ◽

Dioxin Contamination

Although it has been a half-century since dioxin-contaminated herbicides were used to defoliate the landscape during the Vietnam War, dioxin contamination “hotspots” still remain in Vietnam. Environmental and health impacts of these hotspots need to be evaluated. Intellectual disability (ID) is one of the diseases found in the children of people exposed to the herbicides. This study aims to identify genetic alterations of a patient whose family lived in a dioxin hotspot. The patient’s father had a highly elevated dioxin concentration. He was affected with undiagnosed moderate ID. To analyze de novo mutations and genetic variations, and to identify causal gene(s) for ID, we performed whole genome sequencing (WGS) of the proband and his parents. Two de novo missense mutations were detected, each one in ETS2 and ZNF408 genes, respectively. Compound heterozygosity was identified in CENPF and TTN genes. Existing knowledge on the genes and bioinformatics analyses suggest that EST2, ZNF408, and CENPF might be promising candidates for ID causative genes.

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Integrating Whole-Genome Sequencing in Clinical Genetics: A Novel Disruptive Structural Rearrangement Identified in the Dystrophin Gene (DMD)

International Journal of Molecular Sciences ◽

10.3390/ijms23010059 ◽

2021 ◽

Vol 23 (1) ◽

pp. 59

Author(s):

Ana Gonçalves ◽

Ana Fortuna ◽

Yavuz Ariyurek ◽

Márcia E. Oliveira ◽

Goreti Nadais ◽

...

Keyword(s):

Whole Genome Sequencing ◽

Genome Sequencing ◽

Clinical Laboratory ◽

Dystrophin Gene ◽

Genetic Alterations ◽

Molecular Techniques ◽

Clinical Genetics ◽

Whole Genome ◽

Transcript Analysis ◽

Mild Intellectual Disability

While in most patients the identification of genetic alterations causing dystrophinopathies is a relatively straightforward task, a significant number require genomic and transcriptomic approaches that go beyond a routine diagnostic set-up. In this work, we present a Becker Muscular Dystrophy patient with elevated creatinine kinase levels, progressive muscle weakness, mild intellectual disability and a muscle biopsy showing dystrophic features and irregular dystrophin labelling. Routine molecular techniques (Southern-blot analysis, multiplex PCR, MLPA and genomic DNA sequencing) failed to detect a defect in the DMD gene. Muscle DMD transcript analysis (RT-PCR and cDNA-MLPA) showed the absence of exons 75 to 79, seen to be present at the genomic level. These results prompted the application of low-coverage linked-read whole-genome sequencing (WGS), revealing a possible rearrangement involving DMD intron 74 and a region located upstream of the PRDX4 gene. Breakpoint PCR and Sanger sequencing confirmed the presence of a ~8 Mb genomic inversion. Aberrant DMD transcripts were subsequently identified, some of which contained segments from the region upstream of PRDX4. Besides expanding the mutational spectrum of the disorder, this study reinforces the importance of transcript analysis in the diagnosis of dystrophinopathies and shows how WGS has a legitimate role in clinical laboratory genetics.

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