1
|
Farris J, Khanna C, Smadbeck JB, Johnson SH, Bothun E, Kaplan T, Hoffman F, Polonis K, Oliver G, Reis LM, Semina EV, Rust L, Hoppman NL, Vasmatzis G, Marcou CA, Schimmenti LA, Klee EW. Complex balanced intrachromosomal rearrangement involving PITX2 identified as a cause of Axenfeld-Rieger Syndrome. Am J Med Genet A 2024; 194:e63542. [PMID: 38234180 PMCID: PMC11003841 DOI: 10.1002/ajmg.a.63542] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 12/15/2023] [Accepted: 01/07/2024] [Indexed: 01/19/2024]
Abstract
Axenfeld-Rieger Syndrome (ARS) type 1 is a rare autosomal dominant condition characterized by anterior chamber anomalies, umbilical defects, dental hypoplasia, and craniofacial anomalies, with Meckel's diverticulum in some individuals. Here, we describe a clinically ascertained female of childbearing age with ARS for whom clinical targeted sequencing and deletion/duplication analysis followed by clinical exome and genome sequencing resulted in no pathogenic variants or variants of unknown significance in PITX2 or FOXC1. Advanced bioinformatic analysis of the genome data identified a complex, balanced rearrangement disrupting PITX2. This case is the first reported intrachromosomal rearrangement leading to ARS, illustrating that for patients with compelling clinical phenotypes but negative genomic testing, additional bioinformatic analysis are essential to identify subtle genomic abnormalities in target genes.
Collapse
Affiliation(s)
- Joseph Farris
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Cheryl Khanna
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
| | - James B Smadbeck
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Sarah H Johnson
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Erick Bothun
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
| | - Tyler Kaplan
- Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, USA
| | - Francis Hoffman
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Katarzyna Polonis
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Gavin Oliver
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Linda M Reis
- Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Wisconsin, Milwaukee, Wisconsin, USA
| | - Elena V Semina
- Department of Pediatrics and Children's Research Institute, Medical College of Wisconsin and Children's Wisconsin, Milwaukee, Wisconsin, USA
- Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Laura Rust
- Department of Clinical Genomics, Mayo Clinic, Rochester, Minnesota, USA
| | - Nicole L Hoppman
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - George Vasmatzis
- Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, USA
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota, USA
| | - Cherisse A Marcou
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | - Lisa A Schimmenti
- Department of Clinical Genomics, Mayo Clinic, Rochester, Minnesota, USA
| | - Eric W Klee
- Center for Individualized Medicine, Mayo Clinic, Rochester, Minnesota, USA
- Department of Quantitative Health Sciences, Mayo Clinic, Rochester, Minnesota, USA
| |
Collapse
|
2
|
David D, Fino J, Oliveira R, Dória S, Morton CC. Balanced chromosomal rearrangements implicate YIPF5 and SPATC1L in non-obstructive oligoasthenozoospermia and oligozoospermia and of a derivative chromosome 22 in recurrent miscarriage. Gene 2023; 887:147737. [PMID: 37625567 DOI: 10.1016/j.gene.2023.147737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/10/2023] [Accepted: 08/22/2023] [Indexed: 08/27/2023]
Abstract
Naturally occurring balanced, unbalanced, and complex chromosomal rearrangements have been reported to cause pathogenic genomic or genetic variants leading to infertility and recurrent miscarriage. Therefore, balanced chromosomal rearrangements were used as genomic signposts for identification of candidate genes or genomic loci associated with male infertility due to defects of spermatogenesis, or with recurrent miscarriage. In three male probands, structural chromosomal variants and copy number variants were identified at nucleotide resolution by long-insert genome sequencing approaches and Sanger sequencing. The pathogenic potential of these and affected candidate genes was assessed based on convergent genomic and genotype-phenotype correlation data. Identification of balanced chromosomal rearrangement breakpoints and interpretation in the context of their genomic background of structural and copy number variants led us to conclude that the infertility due to oligoasthenozoospermia and oligozoospermia is most likely associated with a position effect on YIPF5 and SPATC1L, respectively. In a third proband with intellectual disability and recurrent miscarriage, disruption of CAMK2B causing autosomal dominant, intellectual developmental disorder 54 and increased meiotic segregation during gametogenesis of a der(22) are responsible for the reported phenotype. Our data further support the existence of loci at 5q23 and 21q22.3 for these spermatogenesis defects and highlight the importance of the naturally occurring balanced chromosomal rearrangements for assessment of the pathogenic mechanisms. Furthermore, we show comorbidities due to the same balanced chromosomal rearrangement caused by different pathogenic mechanisms.
Collapse
Affiliation(s)
- Dezső David
- Department of Human Genetics, National Institute of Health Doctor Ricardo Jorge, 1649-016 Lisbon, Portugal.
| | - Joana Fino
- Department of Human Genetics, National Institute of Health Doctor Ricardo Jorge, 1649-016 Lisbon, Portugal
| | - Renata Oliveira
- Medical Genetics Service, University Hospital Centre of São João, 4200-319 Porto, Portugal
| | - Sofia Dória
- Department of Pathology, Genetics Service, Faculty of Medicine, University of Porto, 4200-450 Porto, Portugal; I3S-Health Research and Innovation Institute, University of Porto, 4200-135 Porto, Portugal
| | - Cynthia C Morton
- Department of Obstetrics and Gynecology and of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Manchester Centre for Audiology and Deafness (ManCAD), University of Manchester M13 9PL, UK
| |
Collapse
|
3
|
Allou L, Mundlos S. Disruption of regulatory domains and novel transcripts as disease-causing mechanisms. Bioessays 2023; 45:e2300010. [PMID: 37381881 DOI: 10.1002/bies.202300010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 05/24/2023] [Accepted: 06/06/2023] [Indexed: 06/30/2023]
Abstract
Deletions, duplications, insertions, inversions, and translocations, collectively called structural variations (SVs), affect more base pairs of the genome than any other sequence variant. The recent technological advancements in genome sequencing have enabled the discovery of tens of thousands of SVs per human genome. These SVs primarily affect non-coding DNA sequences, but the difficulties in interpreting their impact limit our understanding of human disease etiology. The functional annotation of non-coding DNA sequences and methodologies to characterize their three-dimensional (3D) organization in the nucleus have greatly expanded our understanding of the basic mechanisms underlying gene regulation, thereby improving the interpretation of SVs for their pathogenic impact. Here, we discuss the various mechanisms by which SVs can result in altered gene regulation and how these mechanisms can result in rare genetic disorders. Beyond changing gene expression, SVs can produce novel gene-intergenic fusion transcripts at the SV breakpoints.
Collapse
Affiliation(s)
- Lila Allou
- RG Development & Disease, Max Planck Institute for Molecular Genetics, Berlin, Germany
- Institute for Medical and Human Genetics, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Stefan Mundlos
- RG Development & Disease, Max Planck Institute for Molecular Genetics, Berlin, Germany
- Institute for Medical and Human Genetics, Charité-Universitätsmedizin Berlin, Berlin, Germany
- Berlin-Brandenburg Center for Regenerative Therapies, Charité-Universitätsmedizin Berlin, Berlin, Germany
| |
Collapse
|
4
|
Di-Battista A, Favilla BP, Zamariolli M, Nunes N, Defelicibus A, Armelin-Correa L, da Silva IT, Reymond A, Moyses-Oliveira M, Melaragno MI. Premature ovarian insufficiency is associated with global alterations in the regulatory landscape and gene expression in balanced X-autosome translocations. Epigenetics Chromatin 2023; 16:19. [PMID: 37202802 DOI: 10.1186/s13072-023-00493-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 05/04/2023] [Indexed: 05/20/2023] Open
Abstract
BACKGROUND Patients with balanced X-autosome translocations and premature ovarian insufficiency (POI) constitute an interesting paradigm to study the effect of chromosome repositioning. Their breakpoints are clustered within cytobands Xq13-Xq21, 80% of them in Xq21, and usually, no gene disruption can be associated with POI phenotype. As deletions within Xq21 do not cause POI, and since different breakpoints and translocations with different autosomes lead to this same gonadal phenotype, a "position effect" is hypothesized as a possible mechanism underlying POI pathogenesis. OBJECTIVE AND METHODS To study the effect of the balanced X-autosome translocations that result in POI, we fine-mapped the breakpoints in six patients with POI and balanced X-autosome translocations and addressed gene expression and chromatin accessibility changes in four of them. RESULTS We observed differential expression in 85 coding genes, associated with protein regulation, multicellular regulation, integrin signaling, and immune response pathways, and 120 differential peaks for the three interrogated histone marks, most of which were mapped in high-activity chromatin state regions. The integrative analysis between transcriptome and chromatin data pointed to 12 peaks mapped less than 2 Mb from 11 differentially expressed genes in genomic regions not related to the patients' chromosomal rearrangement, suggesting that translocations have broad effects on the chromatin structure. CONCLUSION Since a wide impact on gene regulation was observed in patients, our results observed in this study support the hypothesis of position effect as a pathogenic mechanism for premature ovarian insufficiency associated with X-autosome translocations. This work emphasizes the relevance of chromatin changes in structural variation, since it advances our knowledge of the impact of perturbations in the regulatory landscape within interphase nuclei, resulting in the position effect pathogenicity.
Collapse
Affiliation(s)
- Adriana Di-Battista
- Genetics Division, Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, 04023-900, Brazil
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Bianca Pereira Favilla
- Genetics Division, Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, 04023-900, Brazil
| | - Malú Zamariolli
- Genetics Division, Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, 04023-900, Brazil
| | - Natália Nunes
- Genetics Division, Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, 04023-900, Brazil
| | - Alexandre Defelicibus
- Laboratory of Bioinformatics and Computational Biology, A. C. Camargo Cancer Center, São Paulo, Brazil
| | - Lucia Armelin-Correa
- Department of Biological Sciences, Universidade Federal São Paulo, Diadema, Brazil
| | - Israel Tojal da Silva
- Laboratory of Bioinformatics and Computational Biology, A. C. Camargo Cancer Center, São Paulo, Brazil
| | - Alexandre Reymond
- Center for Integrative Genomics, University of Lausanne, Lausanne, Switzerland
| | - Mariana Moyses-Oliveira
- Genetics Division, Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, 04023-900, Brazil
- Sleep Institute, Associação Fundo de Incentivo à Pesquisa, São Paulo, Brazil
| | - Maria Isabel Melaragno
- Genetics Division, Department of Morphology and Genetics, Universidade Federal de São Paulo, São Paulo, 04023-900, Brazil.
| |
Collapse
|
5
|
Poszewiecka B, Pienkowski VM, Nowosad K, Robin JD, Gogolewski K, Gambin A. TADeus2: a web server facilitating the clinical diagnosis by pathogenicity assessment of structural variations disarranging 3D chromatin structure. Nucleic Acids Res 2022; 50:W744-W752. [PMID: 35524567 PMCID: PMC9252839 DOI: 10.1093/nar/gkac318] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Revised: 04/12/2022] [Accepted: 04/21/2022] [Indexed: 01/01/2023] Open
Abstract
In recent years great progress has been made in identification of structural variants (SV) in the human genome. However, the interpretation of SVs, especially located in non-coding DNA, remains challenging. One of the reasons stems in the lack of tools exclusively designed for clinical SVs evaluation acknowledging the 3D chromatin architecture. Therefore, we present TADeus2 a web server dedicated for a quick investigation of chromatin conformation changes, providing a visual framework for the interpretation of SVs affecting topologically associating domains (TADs). This tool provides a convenient visual inspection of SVs, both in a continuous genome view as well as from a rearrangement’s breakpoint perspective. Additionally, TADeus2 allows the user to assess the influence of analyzed SVs within flaking coding/non-coding regions based on the Hi-C matrix. Importantly, the SVs pathogenicity is quantified and ranked using TADA, ClassifyCNV tools and sampling-based P-value. TADeus2 is publicly available at https://tadeus2.mimuw.edu.pl.
Collapse
Affiliation(s)
- Barbara Poszewiecka
- Faculty of Mathematics, Informatics, and Mechanics, University of Warsaw, 2 Banacha street, 02-097 Warsaw, Poland
| | - Victor Murcia Pienkowski
- Aix Marseille Univ, INSERM, Marseille Medical Genetics, MMG, Marseille, France.,Department of Medical Genetics, Medical University of Warsaw, Adolfa Pawińskiego 3c, 02-106 Warsaw, Poland
| | - Karol Nowosad
- Department of Cell Biology, Erasmus Medical Center, Doctor Molewaterplein 40, 3015 GD Rotterdam, Netherlands.,Department of Biomedical Sciences, Laboratory of Molecular Genetics, Medical University of Lublin, Doktora Witolda Chodźki 1, 20-400 Lublin, Poland.,The Postgraduate School of Molecular Medicine, Medical University of Warsaw, Żwirki i Wigury 61, 02-091 Warsaw, Poland
| | - Jérôme D Robin
- Aix Marseille Univ, INSERM, Marseille Medical Genetics, MMG, Marseille, France
| | - Krzysztof Gogolewski
- Faculty of Mathematics, Informatics, and Mechanics, University of Warsaw, 2 Banacha street, 02-097 Warsaw, Poland
| | - Anna Gambin
- Faculty of Mathematics, Informatics, and Mechanics, University of Warsaw, 2 Banacha street, 02-097 Warsaw, Poland
| |
Collapse
|
6
|
Khan K, Ahram DF, Liu YP, Westland R, Sampogna RV, Katsanis N, Davis EE, Sanna-Cherchi S. Multidisciplinary approaches for elucidating genetics and molecular pathogenesis of urinary tract malformations. Kidney Int 2022; 101:473-484. [PMID: 34780871 PMCID: PMC8934530 DOI: 10.1016/j.kint.2021.09.034] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 09/15/2021] [Accepted: 09/30/2021] [Indexed: 12/28/2022]
Abstract
Advances in clinical diagnostics and molecular tools have improved our understanding of the genetically heterogeneous causes underlying congenital anomalies of kidney and urinary tract (CAKUT). However, despite a sharp incline of CAKUT reports in the literature within the past 2 decades, there remains a plateau in the genetic diagnostic yield that is disproportionate to the accelerated ability to generate robust genome-wide data. Explanations for this observation include (i) diverse inheritance patterns with incomplete penetrance and variable expressivity, (ii) rarity of single-gene drivers such that large sample sizes are required to meet the burden of proof, and (iii) multigene interactions that might produce either intra- (e.g., copy number variants) or inter- (e.g., effects in trans) locus effects. These challenges present an opportunity for the community to implement innovative genetic and molecular avenues to explain the missing heritability and to better elucidate the mechanisms that underscore CAKUT. Here, we review recent multidisciplinary approaches at the intersection of genetics, genomics, in vivo modeling, and in vitro systems toward refining a blueprint for overcoming the diagnostic hurdles that are pervasive in urinary tract malformation cohorts. These approaches will not only benefit clinical management by reducing age at molecular diagnosis and prompting early evaluation for comorbid features but will also serve as a springboard for therapeutic development.
Collapse
Affiliation(s)
- Kamal Khan
- Center for Human Disease Modeling, Duke University, Durham, North Carolina, USA.,Stanley Manne Children’s Research Institute, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, Illinois, USA (current address)
| | - Dina F. Ahram
- Division of Nephrology, Columbia University, New York, USA
| | - Yangfan P. Liu
- Center for Human Disease Modeling, Duke University, Durham, North Carolina, USA
| | - Rik Westland
- Division of Nephrology, Columbia University, New York, USA.,Department of Pediatric Nephrology, Amsterdam UMC- Emma Children’s Hospital, Amsterdam, NL
| | | | - Nicholas Katsanis
- Center for Human Disease Modeling, Duke University, Durham, North Carolina, USA; Stanley Manne Children's Research Institute, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, Illinois, USA (current address); Department of Pediatrics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA; Department of Cell and Developmental Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.
| | - Erica E. Davis
- Center for Human Disease Modeling, Duke University, Durham, North Carolina, USA.,Stanley Manne Children’s Research Institute, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, Illinois, USA (current address).,Department of Pediatrics and Department of Cell and Molecular Biology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA.,To whom correspondence should be addressed: ADDRESS CORRESPONDENCE TO: Simone Sanna-Cherchi, MD, Division of Nephrology, Columbia University, College of Physicians and Surgeons, New York, NY 10032, USA; Phone: 212-851-4925; Fax: 212-851-5461; . Erica E. Davis, PhD, Stanley Manne Children’s Research Institute, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL 60611, USA; Phone: 312-503-7662; Fax: 312-503-7343; , Nicholas Katsanis, PhD, Stanley Manne Children’s Research Institute, Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago, IL 60611, USA; Phone: 312-503-7339; Fax: 312-503-7343;
| | - Simone Sanna-Cherchi
- Department of Medicine, Division of Nephrology, Columbia University Irving Medical Center, New York, New York, USA.
| |
Collapse
|
7
|
Kovaleva NV, Cotter PD. Factors affecting clinical manifestation of chromosomal imbalance in carriers of segmental autosomal mosaicism: differential impact of gender. J Appl Genet 2022; 63:281-291. [PMID: 34973130 PMCID: PMC8979927 DOI: 10.1007/s13353-021-00673-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 11/03/2021] [Accepted: 11/25/2021] [Indexed: 11/25/2022]
Abstract
Mosaicism for unbalanced chromosomal rearrangements segmental mosaicism (SM) is rare, both in patients referred for cytogenetic testing and in prenatal diagnoses. In contrast, in preimplantation embryos SM is a frequent finding and, therefore, is even more challenging. However, there is no consistency among results of published studies on the clinical outcomes of embryos with SM, primarily due to the small number of reported cases. Moreover, there is the problem of predicting the potential for the optimal development of a mosaic embryo to a healthy individual. Therefore, we suggested comparing factors predisposing to favorable and poor prognoses, identified in postnatal and prenatal cohorts of SM carriers, with those obtained from studies on preimplantation embryos. We analyzed 580 published cases of SM including (i) postnatally diagnosed affected carriers, (ii) clinically asymptomatic carriers, (iii) prenatally diagnosed carriers, and (iv) miscarriages. We observed a concordance with preimplantation diagnoses regarding the clinical significance of the extent of mosaicism as well as a predominance of deletions over other types of rearrangements. However, there is no concordance regarding excessive involvement of chromosomes 1, 5, and 9 in unbalanced rearrangements and a preferential involvement of larger chromosomes compared to short ones. Paternal age was not found to be associated with SM in postnatally disease-defined individuals. We have identified maternal age and preferential involvement of chromosome 18 in rearrangements associated with clinical manifestations. Male predominance was found among normal pregnancy outcomes and among disease-defined carriers of rearrangements resulting in a gain of genomic material. Female predominance was found among abnormal pregnancy outcomes, among disease-defined carriers of loss and gain/loss rearrangements, and among transmitting carriers of gonadal SM, both affected and asymptomatic. According to data obtained from “post-embryo” studies, clinical manifestations of chromosomal imbalance are associated with a high proportion of abnormal cells, female gender, the type of rearrangement and involved chromosome(s), and maternal age. We believe these data are instructive in the challenging medical genetic counseling of parents faced with no option other than transfer of an embryo with segmental mosaicism.
Collapse
Affiliation(s)
- Natalia V Kovaleva
- Academy of Molecular Medicine, Mytninskaya str., 12/44, St. Petersburg, 191144, Russian Federation.
| | | |
Collapse
|
8
|
Fino J, Marques B, Dong Z, David D. SVInterpreter: A Comprehensive Topologically Associated Domain-Based Clinical Outcome Prediction Tool for Balanced and Unbalanced Structural Variants. Front Genet 2021; 12:757170. [PMID: 34925449 PMCID: PMC8671832 DOI: 10.3389/fgene.2021.757170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 10/12/2021] [Indexed: 11/13/2022] Open
Abstract
With the advent of genomic sequencing, a number of balanced and unbalanced structural variants (SVs) can be detected per individual. Mainly due to incompleteness and the scattered nature of the available annotation data of the human genome, manual interpretation of the SV's clinical significance is laborious and cumbersome. Since bioinformatic tools developed for this task are limited, a comprehensive tool to assist clinical outcome prediction of SVs is warranted. Herein, we present SVInterpreter, a free Web application, which analyzes both balanced and unbalanced SVs using topologically associated domains (TADs) as genome units. Among others, gene-associated data (as function and dosage sensitivity), phenotype similarity scores, and copy number variants (CNVs) scoring metrics are retrieved for an informed SV interpretation. For evaluation, we retrospectively applied SVInterpreter to 97 balanced (translocations and inversions) and 125 unbalanced (deletions, duplications, and insertions) previously published SVs, and 145 SVs identified from 20 clinical samples. Our results showed the ability of SVInterpreter to support the evaluation of SVs by (1) confirming more than half of the predictions of the original studies, (2) decreasing 40% of the variants of uncertain significance, and (3) indicating several potential position effect events. To our knowledge, SVInterpreter is the most comprehensive TAD-based tool to identify the possible disease-causing candidate genes and to assist prediction of the clinical outcome of SVs. SVInterpreter is available at http://dgrctools-insa.min-saude.pt/cgi-bin/SVInterpreter.py.
Collapse
Affiliation(s)
- Joana Fino
- Department of Human Genetics, National Health Institute Doutor Ricardo Jorge, Lisbon, Portugal
| | - Bárbara Marques
- Department of Human Genetics, National Health Institute Doutor Ricardo Jorge, Lisbon, Portugal
| | - Zirui Dong
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong, China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China.,Hong Kong Hub of Pediatric Excellence, The Chinese University of Hong Kong, Hong Kong, China
| | - Dezső David
- Department of Human Genetics, National Health Institute Doutor Ricardo Jorge, Lisbon, Portugal
| |
Collapse
|
9
|
Srikanth S, Jain L, Zepeda-Mendoza C, Cascio L, Jones K, Pauly R, DuPont B, Rogers C, Sarasua S, Phelan K, Morton C, Boccuto L. Position effects of 22q13 rearrangements on candidate genes in Phelan-McDermid syndrome. PLoS One 2021; 16:e0253859. [PMID: 34228749 PMCID: PMC8259982 DOI: 10.1371/journal.pone.0253859] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 06/15/2021] [Indexed: 11/19/2022] Open
Abstract
Phelan-McDermid syndrome (PMS) is a multi-system disorder characterized by significant variability in clinical presentation. The genetic etiology is also variable with differing sizes of deletions in the chromosome 22q13 region and types of genetic abnormalities (e.g., terminal or interstitial deletions, translocations, ring chromosomes, or SHANK3 variants). Position effects have been shown to affect gene expression and function and play a role in the clinical presentation of various genetic conditions. This study employed a topologically associating domain (TAD) analysis approach to investigate position effects of chromosomal rearrangements on selected candidate genes mapped to 22q13 in 81 individuals with PMS. Data collected were correlated with clinical information from these individuals and with expression and metabolic profiles of lymphoblastoid cells from selected cases. The data confirmed TAD predictions for genes encompassed in the deletions and the clinical and molecular data indicated clear differences among individuals with different 22q13 deletion sizes. The results of the study indicate a positive correlation between deletion size and phenotype severity in PMS and provide evidence of the contribution of other genes to the clinical variability in this developmental disorder by reduced gene expression and altered metabolomics.
Collapse
Affiliation(s)
- Sujata Srikanth
- Greenwood Genetic Center, Greenwood, SC, United States of America
| | - Lavanya Jain
- School of Nursing, Healthcare Genetics Program, Clemson University, Clemson, SC, United States of America
| | - Cinthya Zepeda-Mendoza
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women’s Hospital, Boston, MA, United States of America
- Harvard Medical School, Boston, MA, United States of America
| | - Lauren Cascio
- Greenwood Genetic Center, Greenwood, SC, United States of America
| | - Kelly Jones
- Greenwood Genetic Center, Greenwood, SC, United States of America
| | - Rini Pauly
- Greenwood Genetic Center, Greenwood, SC, United States of America
| | - Barb DuPont
- Greenwood Genetic Center, Greenwood, SC, United States of America
| | - Curtis Rogers
- Greenwood Genetic Center, Greenwood, SC, United States of America
| | - Sara Sarasua
- School of Nursing, Healthcare Genetics Program, Clemson University, Clemson, SC, United States of America
| | - Katy Phelan
- Genetics Laboratory, Florida Cancer Specialists and Research Institute, Fort Myers, FL, United States of America
| | - Cynthia Morton
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women’s Hospital, Boston, MA, United States of America
- Harvard Medical School, Boston, MA, United States of America
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA, United States of America
- Department of Pathology, Brigham and Women’s Hospital, Boston, MA, United States of America
- Division of Human Communication, Development and Hearing, School of Biological Sciences, Manchester Academic Health Science Center, Manchester, United Kingdom
| | - Luigi Boccuto
- Greenwood Genetic Center, Greenwood, SC, United States of America
- School of Nursing, College of Behavioral, Social and Health Sciences, Clemson University, Clemson, SC, United States of America
| |
Collapse
|
10
|
Villela D, Mazzonetto PC, Migliavacca MP, Perrone E, Guida G, Milanezi MFG, Jorge AAL, Ribeiro-Bicudo LA, Kok F, Campagnari F, de Rosso-Giuliani L, da Costa SS, Vianna-Morgante AM, Pearson PL, Krepischi ACV, Rosenberg C. Congenital chromoanagenesis in the routine postnatal chromosomal microarray analyses. Am J Med Genet A 2021; 185:2335-2344. [PMID: 33988290 DOI: 10.1002/ajmg.a.62237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 02/19/2021] [Accepted: 02/26/2021] [Indexed: 11/07/2022]
Abstract
Chromosomal microarray analyses (CMA) have greatly increased both the yield and diagnostic accuracy of postnatal analysis; it has been used as a first-tier cytogenetic test in patients with intellectual disability, autism spectrum disorder, and multiple congenital abnormalities. During the last 15 years, we performed CMA in approximately 8,000 patients with neurodevelopmental and/or congenital disorders, of which 13 (0.16%) genetically catastrophic complex chromosomal rearrangements were identified. These ultrarare rearrangements showed clustering of breakpoints, characteristic of chromoanagenesis events. Al1 13 complex events display underlying formation mechanisms, originating either by a synchronization of the shattering of clustered chromosome regions in which regional asynchrony of DNA replication may be one of the main causes of disruption. We provide an overview of the copy number profiling in these patients. Although several previous studies have suggested that chromoanagenesis is often a genetic disease source in postnatal diagnostic screening, due to either the challenge of clinical interpretation of these complex rearrangements or the limitation of microarray resolution relative to the small size and complexity of chromogenic induced chromosome abnormalities, bringing further attention and to study its occurrence in the clinical setting is extremely important.
Collapse
Affiliation(s)
- Darine Villela
- The Human Genome and Stem Cell Research Center, Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil.,GeneOne, DASA, Brazil
| | | | | | - Eduardo Perrone
- GeneOne, DASA, Brazil.,Department of Clinical Genetics, Federal University of São Paulo (UNIFESP), São Paulo, Brazil
| | | | | | - Alexander A L Jorge
- Genetic Endocrinology Unit, Laboratory of Cellular and Molecular Endocrinology LIM25, Division of Endocrinology and Metabology, Clinical Hospital of University of São Paulo Medical School (FMUSP), São Paulo, Brazil
| | | | | | | | - Liane de Rosso-Giuliani
- University Hospital Maria Aparecida Pedrossian, Federal University of Mato Grosso Do Sul (HUMAP-UFMS), Campo Grande, Brazil
| | - Silvia Souza da Costa
- The Human Genome and Stem Cell Research Center, Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Angela M Vianna-Morgante
- The Human Genome and Stem Cell Research Center, Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Peter L Pearson
- The Human Genome and Stem Cell Research Center, Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Ana C V Krepischi
- The Human Genome and Stem Cell Research Center, Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Carla Rosenberg
- The Human Genome and Stem Cell Research Center, Department of Genetics and Evolutionary Biology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil.,GeneOne, DASA, Brazil
| |
Collapse
|
11
|
Vorstman J, Scherer SW. What a finding of gene copy number variation can add to the diagnosis of developmental neuropsychiatric disorders. Curr Opin Genet Dev 2021; 68:18-25. [PMID: 33454514 DOI: 10.1016/j.gde.2020.12.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 12/14/2020] [Accepted: 12/22/2020] [Indexed: 11/26/2022]
Abstract
Among medical disciplines, diagnosis in psychiatry depends highly upon descriptive signs and symptoms, rather than biomarkers. Clear descriptions of specific genetic etiologies have been lacking; genomic technologies, however, are rapidly changing that landscape. Notably, chromosomal microarrays-which detect gene copy number variants (CNVs)-are a recommended standard of care for neurodevelopmental disorders. As a result, an increasing number of patients now receive a clinical diagnosis based on the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) and an identified genetic etiological variant. However, psychiatric and genetic diagnoses are frequently communicated and managed as two disconnected diagnostic parameters. Here, we advocate for a transition model, allowing the integration of genetic etiological information-starting with diagnostically proven CNVs-within the DSM-5 classification framework.
Collapse
Affiliation(s)
- Jacob Vorstman
- Department of Psychiatry, Hospital for Sick Children University of Toronto, Toronto, ON, Canada; Program in Genetics and Genome Biology, Hospital for Sick Children, Canada; The Centre for Applied Genomics, Hospital for Sick Children, Canada
| | - Stephen W Scherer
- Program in Genetics and Genome Biology, Hospital for Sick Children, Canada; The Centre for Applied Genomics, Hospital for Sick Children, Canada; McLaughlin Centre and Department of Molecular Genetics, University of Toronto, Canada.
| |
Collapse
|
12
|
Marcou CA, Pitel B, Hagen CE, Boczek NJ, Rowsey RA, Baughn LB, Hoppman NL, Thorland EC, Kearney HM. Limited diagnostic impact of duplications <1 Mb of uncertain clinical significance: a 10-year retrospective analysis of reporting practices at the Mayo Clinic. Genet Med 2020; 22:2120-2124. [PMID: 32820244 DOI: 10.1038/s41436-020-0932-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 07/26/2020] [Accepted: 07/28/2020] [Indexed: 11/09/2022] Open
Abstract
PURPOSE Copy-number variants (CNVs) of uncertain clinical significance are routinely reported in a clinical setting only when exceeding predetermined reporting thresholds, typically based on CNV size. Given that very few genes are associated with triplosensitive phenotypes, it is not surprising that many interstitial duplications <1 Mb are found to be inherited and anticipated to be of limited or no clinical significance. METHODS In an effort to further refine our reporting criteria to maximize diagnostic yield while minimizing the return of uncertain variants, we performed a retrospective analysis of all clinical microarray cases reported in a 10-year window. A total of 1112 reported duplications had parental follow-up, and these were compared by size, RefSeq gene content, and inheritance pattern. De novo origin was used as a rough proxy for pathogenicity. RESULTS Approximately 6% of duplications 500 kb-1 Mb were de novo observations, compared with approximately 14% for 1-2 Mb duplications (p = 0.0005). On average, de novo duplications had higher gene counts than inherited duplications. CONCLUSION Our data reveal limited diagnostic utility for duplications of uncertain significance <1 Mb. Considerations for revised reporting criteria are discussed and are applicable to CNVs detected by any genome-wide exploratory methodology, including exome/genome sequencing.
Collapse
Affiliation(s)
- Cherisse A Marcou
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
| | - Beth Pitel
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Clinton E Hagen
- Department of Health Sciences Research, Mayo Clinic, Rochester, MN, USA
| | - Nicole J Boczek
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Ross A Rowsey
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Linda B Baughn
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Nicole L Hoppman
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Erik C Thorland
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| | - Hutton M Kearney
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA
| |
Collapse
|
13
|
Sánchez-Gaya V, Mariner-Faulí M, Rada-Iglesias A. Rare or Overlooked? Structural Disruption of Regulatory Domains in Human Neurocristopathies. Front Genet 2020; 11:688. [PMID: 32765580 PMCID: PMC7379850 DOI: 10.3389/fgene.2020.00688] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 06/04/2020] [Indexed: 12/15/2022] Open
Abstract
In the last few years, the role of non-coding regulatory elements and their involvement in human disease have received great attention. Among the non-coding regulatory sequences, enhancers are particularly important for the proper establishment of cell type-specific gene-expression programs. Furthermore, the disruption of enhancers can lead to human disease through two main mechanisms: (i) Mutations or copy number variants can directly alter the enhancer sequences and thereby affect expression of their target genes; (ii) structural variants can provoke changes in 3-D chromatin organization that alter neither the enhancers nor their target genes, but rather the physical communication between them. In this review, these pathomechanisms are mostly discussed in the context of neurocristopathies, congenital disorders caused by defects that occur during neural crest development. We highlight why, due to its contribution to multiple tissues and organs, the neural crest represents an important, yet understudied, cell type involved in multiple congenital disorders. Moreover, we discuss currently available resources and experimental models for the study of human neurocristopathies. Last, we provide some practical guidelines that can be followed when investigating human neurocristopathies caused by structural variants. Importantly, these guidelines can be useful not only to uncover the etiology of human neurocristopathies, but also of other human congenital disorders in which enhancer disruption is involved.
Collapse
Affiliation(s)
- Víctor Sánchez-Gaya
- Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), Consejo Superior de Investigaciones Científicas-University of Cantabria-Sociedad para el Desarrollo de Cantabria, Santander, Spain
| | - Maria Mariner-Faulí
- Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), Consejo Superior de Investigaciones Científicas-University of Cantabria-Sociedad para el Desarrollo de Cantabria, Santander, Spain
| | - Alvaro Rada-Iglesias
- Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), Consejo Superior de Investigaciones Científicas-University of Cantabria-Sociedad para el Desarrollo de Cantabria, Santander, Spain
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Cologne, Germany
- Cluster of Excellence Cellular Stress Responses in Aging-Associated Diseases (CECAD), University of Cologne, Cologne, Germany
| |
Collapse
|
14
|
Genotoxic potential of a novel PDE-4B inhibitor Apremilast by chromosomal aberration and micronucleus assay in mice. Saudi Pharm J 2020; 28:615-620. [PMID: 32435143 PMCID: PMC7229325 DOI: 10.1016/j.jsps.2020.03.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Accepted: 03/29/2020] [Indexed: 11/20/2022] Open
Abstract
Objective Researchers have confirmed that chronic administration of drugs at high doses causes genotoxicity which serve as first step in development of cancers. Apremilast, a phosphodiesterase-4 inhibitor is Food and Drug Administration (FDA) approved drug for Psoriatic Arthritis. The present study designed to conduct genotoxicity testing using the genotoxic study which give simple, sensitive, economical and fast tools for the assessment of damage of genetic material. Methods To conduct genotoxicity study of Apremilast, 60 Swiss albino male mice divided into 6 groups (n = 10). Group1 served as a normal control group without any treatment, Group 2 treated as a disease control and administered with cyclophosphamide 40 mg/kg, IP. Group 3, 4, 5 and 6 treated as test groups and received 10, 20, 40 and 80 mg/kg/day Apremilast respectively. The total duration of study was 13 weeks. At termination day animals were sacrificed and chromosomal aberration assay (BMCAA) and micronucleus assay (BMMNA) were performed to know the genotoxicity potential of Apremilast. Results The results indicates significant rise in chromosomal aberrations (CA) frequency in bone marrow cells and decrease in the MI of the disease control animals as well as Apremilast treated groups. Further significant (p < 0.001; p < 0.0001) increase in score of micronucleated polychromatic erythrocytes (MNPCEs) and percentage of micronucleated PCEs per 1000 PCEs and decrease in the ratio of polychromatic/normochromatic erythrocytes (PCE/NCE) was observed in micronucleus assay. Genotoxic effect increases with the increase of Apremilast dose. Conclusion: Finding of present indicates that Apremilast shows genotoxic potential on high administration although further detailed toxicity studies required for confirmations.
Collapse
|
15
|
Wang H, Dong Z, Zhang R, Chau MHK, Yang Z, Tsang KYC, Wong HK, Gui B, Meng Z, Xiao K, Zhu X, Wang Y, Chen S, Leung TY, Cheung SW, Kwok YK, Morton CC, Zhu Y, Choy KW. Low-pass genome sequencing versus chromosomal microarray analysis: implementation in prenatal diagnosis. Genet Med 2020; 22:500-510. [PMID: 31447483 PMCID: PMC7042067 DOI: 10.1038/s41436-019-0634-7] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Accepted: 07/26/2019] [Indexed: 11/12/2022] Open
Abstract
PURPOSE Emerging studies suggest that low-pass genome sequencing (GS) provides additional diagnostic yield of clinically significant copy-number variants (CNVs) compared with chromosomal microarray analysis (CMA). However, a prospective back-to-back comparison evaluating accuracy, efficacy, and incremental yield of low-pass GS compared with CMA is warranted. METHODS A total of 1023 women undergoing prenatal diagnosis were enrolled. Each sample was subjected to low-pass GS and CMA for CNV analysis in parallel. CNVs were classified according to guidelines of the American College of Medical Genetics and Genomics. RESULTS Low-pass GS not only identified all 124 numerical disorders or pathogenic or likely pathogenic (P/LP) CNVs detected by CMA in 121 cases (11.8%, 121/1023), but also defined 17 additional and clinically relevant P/LP CNVs in 17 cases (1.7%, 17/1023). In addition, low-pass GS significantly reduced the technical repeat rate from 4.6% (47/1023) for CMA to 0.5% (5/1023) and required less DNA (50 ng) as input. CONCLUSION In the context of prenatal diagnosis, low-pass GS identified additional and clinically significant information with enhanced resolution and increased sensitivity of detecting mosaicism as compared with the CMA platform used. This study provides strong evidence for applying low-pass GS as an alternative prenatal diagnostic test.
Collapse
Affiliation(s)
- Huilin Wang
- Maternal-Fetal Medicine Institute, Bao'an Maternity and Child Health Hospital Affiliated to Jinan University School of Medicine, Key Laboratory of Birth Defects Research, Birth Defects Prevention Research and Transformation Team, Shenzhen, China
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
| | - Zirui Dong
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
| | - Rui Zhang
- Maternal-Fetal Medicine Institute, Bao'an Maternity and Child Health Hospital Affiliated to Jinan University School of Medicine, Key Laboratory of Birth Defects Research, Birth Defects Prevention Research and Transformation Team, Shenzhen, China
| | - Matthew Hoi Kin Chau
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
| | - Zhenjun Yang
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
| | - Kathy Yin Ching Tsang
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
| | - Hoi Kin Wong
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
| | - Baoheng Gui
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
| | - Zhuo Meng
- Maternal-Fetal Medicine Institute, Bao'an Maternity and Child Health Hospital Affiliated to Jinan University School of Medicine, Key Laboratory of Birth Defects Research, Birth Defects Prevention Research and Transformation Team, Shenzhen, China
| | - Kelin Xiao
- Maternal-Fetal Medicine Institute, Bao'an Maternity and Child Health Hospital Affiliated to Jinan University School of Medicine, Key Laboratory of Birth Defects Research, Birth Defects Prevention Research and Transformation Team, Shenzhen, China
| | - Xiaofan Zhu
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
| | - Yanfang Wang
- Maternal-Fetal Medicine Institute, Bao'an Maternity and Child Health Hospital Affiliated to Jinan University School of Medicine, Key Laboratory of Birth Defects Research, Birth Defects Prevention Research and Transformation Team, Shenzhen, China
| | - Shaoyun Chen
- Maternal-Fetal Medicine Institute, Bao'an Maternity and Child Health Hospital Affiliated to Jinan University School of Medicine, Key Laboratory of Birth Defects Research, Birth Defects Prevention Research and Transformation Team, Shenzhen, China
| | - Tak Yeung Leung
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China
- The Chinese University of Hong Kong-Baylor College of Medicine Joint Center For Medical Genetics, Hong Kong, China
| | - Sau Wai Cheung
- The Chinese University of Hong Kong-Baylor College of Medicine Joint Center For Medical Genetics, Hong Kong, China
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Yvonne K Kwok
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China
| | - Cynthia C Morton
- Department of Obstetrics and Gynecology, Brigham and Women's Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA.
- Department of Pathology, Brigham and Women's Hospital, Boston, MA, USA.
- Manchester Center for Audiology and Deafness, University of Manchester, Manchester Academic Health Science Center, Manchester, UK.
| | - Yuanfang Zhu
- Maternal-Fetal Medicine Institute, Bao'an Maternity and Child Health Hospital Affiliated to Jinan University School of Medicine, Key Laboratory of Birth Defects Research, Birth Defects Prevention Research and Transformation Team, Shenzhen, China.
| | - Kwong Wai Choy
- Department of Obstetrics & Gynaecology, The Chinese University of Hong Kong, Hong Kong, China.
- Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China.
- The Chinese University of Hong Kong-Baylor College of Medicine Joint Center For Medical Genetics, Hong Kong, China.
| |
Collapse
|
16
|
Middelkamp S, Vlaar JM, Giltay J, Korzelius J, Besselink N, Boymans S, Janssen R, de la Fonteijne L, van Binsbergen E, van Roosmalen MJ, Hochstenbach R, Giachino D, Talkowski ME, Kloosterman WP, Cuppen E. Prioritization of genes driving congenital phenotypes of patients with de novo genomic structural variants. Genome Med 2019; 11:79. [PMID: 31801603 PMCID: PMC6894143 DOI: 10.1186/s13073-019-0692-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Accepted: 11/14/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND Genomic structural variants (SVs) can affect many genes and regulatory elements. Therefore, the molecular mechanisms driving the phenotypes of patients carrying de novo SVs are frequently unknown. METHODS We applied a combination of systematic experimental and bioinformatic methods to improve the molecular diagnosis of 39 patients with multiple congenital abnormalities and/or intellectual disability harboring apparent de novo SVs, most with an inconclusive diagnosis after regular genetic testing. RESULTS In 7 of these cases (18%), whole-genome sequencing analysis revealed disease-relevant complexities of the SVs missed in routine microarray-based analyses. We developed a computational tool to predict the effects on genes directly affected by SVs and on genes indirectly affected likely due to the changes in chromatin organization and impact on regulatory mechanisms. By combining these functional predictions with extensive phenotype information, candidate driver genes were identified in 16/39 (41%) patients. In 8 cases, evidence was found for the involvement of multiple candidate drivers contributing to different parts of the phenotypes. Subsequently, we applied this computational method to two cohorts containing a total of 379 patients with previously detected and classified de novo SVs and identified candidate driver genes in 189 cases (50%), including 40 cases whose SVs were previously not classified as pathogenic. Pathogenic position effects were predicted in 28% of all studied cases with balanced SVs and in 11% of the cases with copy number variants. CONCLUSIONS These results demonstrate an integrated computational and experimental approach to predict driver genes based on analyses of WGS data with phenotype association and chromatin organization datasets. These analyses nominate new pathogenic loci and have strong potential to improve the molecular diagnosis of patients with de novo SVs.
Collapse
Affiliation(s)
- Sjors Middelkamp
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands
| | - Judith M Vlaar
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands
| | - Jacques Giltay
- Department of Genetics, University Medical Center Utrecht, 3584 EA, Utrecht, the Netherlands
| | - Jerome Korzelius
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands
- Max Planck Institute for Biology of Aging, Cologne, Germany
| | - Nicolle Besselink
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands
| | - Sander Boymans
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands
| | - Roel Janssen
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands
| | - Lisanne de la Fonteijne
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands
| | - Ellen van Binsbergen
- Department of Genetics, University Medical Center Utrecht, 3584 EA, Utrecht, the Netherlands
| | - Markus J van Roosmalen
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands
| | - Ron Hochstenbach
- Department of Genetics, University Medical Center Utrecht, 3584 EA, Utrecht, the Netherlands
| | - Daniela Giachino
- Medical Genetics Unit, Department of Clinical and Biological Sciences, University of Torino, 10043, Orbassano, Italy
| | - Michael E Talkowski
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA
- Program in Medical and Population Genetics and Stanley Center for Psychiatric Research, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Wigard P Kloosterman
- Department of Genetics, University Medical Center Utrecht, 3584 EA, Utrecht, the Netherlands
| | - Edwin Cuppen
- Center for Molecular Medicine and Oncode Institute, University Medical Center Utrecht, 3584 CX, Utrecht, the Netherlands.
| |
Collapse
|
17
|
Belokopytova PS, Nuriddinov MA, Mozheiko EA, Fishman D, Fishman V. Quantitative prediction of enhancer-promoter interactions. Genome Res 2019; 30:72-84. [PMID: 31804952 PMCID: PMC6961579 DOI: 10.1101/gr.249367.119] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 11/25/2019] [Indexed: 11/24/2022]
Abstract
Recent experimental and computational efforts have provided large data sets describing three-dimensional organization of mouse and human genomes and showed the interconnection between the expression profile, epigenetic state, and spatial interactions of loci. These interconnections were utilized to infer the spatial organization of chromatin, including enhancer–promoter contacts, from one-dimensional epigenetic marks. Here, we show that the predictive power of some of these algorithms is overestimated due to peculiar properties of the biological data. We propose an alternative approach, which provides high-quality predictions of chromatin interactions using information on gene expression and CTCF-binding alone. Using multiple metrics, we confirmed that our algorithm could efficiently predict the three-dimensional architecture of both normal and rearranged genomes.
Collapse
Affiliation(s)
- Polina S Belokopytova
- Institute of Cytology and Genetics SB RAS 630090, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia 630090
| | | | | | - Daniil Fishman
- Novosibirsk State University, Novosibirsk, Russia 630090
| | - Veniamin Fishman
- Institute of Cytology and Genetics SB RAS 630090, Novosibirsk, Russia.,Novosibirsk State University, Novosibirsk, Russia 630090
| |
Collapse
|
18
|
Chai H, DiAdamo A, Grommisch B, Xu F, Zhou Q, Wen J, Mahoney M, Bale A, McGrath J, Spencer-Manzon M, Li P, Zhang H. A Retrospective Analysis of 10-Year Data Assessed the Diagnostic Accuracy and Efficacy of Cytogenomic Abnormalities in Current Prenatal and Pediatric Settings. Front Genet 2019; 10:1162. [PMID: 31850057 PMCID: PMC6902283 DOI: 10.3389/fgene.2019.01162] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 10/23/2019] [Indexed: 01/01/2023] Open
Abstract
Background: Array comparative genomic hybridization (aCGH), karyotyping and fluorescence in situ hybridization (FISH) analyses have been used in a clinical cytogenetic laboratory. A systematic analysis on diagnostic findings of cytogenomic abnormalities in current prenatal and pediatric settings provides approaches for future improvement. Methods: A retrospective analysis was performed on abnormal findings by aCGH, karyotyping, and FISH from 3,608 prenatal cases and 4,509 pediatric cases during 2008–2017. The diagnostic accuracy was evaluated by comparing the abnormality detection rate (ADR) and the relative frequency (RF) of different types of cytogenomic abnormalities between prenatal and pediatric cases. A linear regression correlation between known prevalence and ADR of genomic disorders was used to extrapolate the prevalence of other genomic disorders. The diagnostic efficacy was estimated as percentage of detected abnormal cases by expected abnormal cases from served population. Results: The composite ADR for numerical chromosome abnormalities, structural chromosome abnormalities, recurrent genomic disorders, and sporadic pathogenic copy number variants (pCNVs) in prenatal cases were 13.03%, 1.77%, 1.69%, and 0.9%, respectively, and were 5.13%, 2.84%, 7.08%, and 2.69% in pediatric cases, respectively. The chromosomal abnormalities detected in prenatal cases (14.80%) were significantly higher than that of pediatric cases (7.97%) (p < 0.05), while the pCNVs detected in prenatal cases (2.59%) were significantly lower than that of pediatric cases (9.77%) (p < 0.05). The prevalence of recurrent genomic disorders and total pCNVs was estimated to be 1/396 and 1/291, respectively. Approximately, 29% and 35% of cytogenomic abnormalities expected from the population served were detected in current prenatal and pediatric diagnostic practice, respectively. Conclusion: For chromosomal abnormalities, effective detection of Down syndrome (DS) and Turner syndrome (TS) and under detection of sex chromosome numerical abnormalities in both prenatal and pediatric cases were noted. For pCNVs, under detection of pCNVs in prenatal cases and effective detection of DiGeorge syndrome (DGS) and variable efficacy in detecting other pCNVs in pediatric cases were noted. Extend aCGH analysis to more prenatal cases with fetal ultrasonographic anomalies, enhanced non-invasive prenatal (NIPT) testing screening for syndromic genomic disorders, and better clinical indications for pCNVs are approaches that could improve diagnostic yield of cytogenomic abnormalities.
Collapse
Affiliation(s)
- Hongyan Chai
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - Autumn DiAdamo
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - Brittany Grommisch
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - Fang Xu
- Prevention Genetics, Marshfield, WI, United States
| | - Qinghua Zhou
- The First Affiliated Hospital, Biomedical Translational Research Institute, Jinan University, Guangzhou, China
| | - Jiadi Wen
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - Maurice Mahoney
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - Allen Bale
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - James McGrath
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - Michele Spencer-Manzon
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - Peining Li
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| | - Hui Zhang
- Department of Genetics, Yale University School of Medicine, New Haven, CT, United States
| |
Collapse
|
19
|
Abstract
Structural and quantitative chromosomal rearrangements, collectively referred to as structural variation (SV), contribute to a large extent to the genetic diversity of the human genome and thus are of high relevance for cancer genetics, rare diseases and evolutionary genetics. Recent studies have shown that SVs can not only affect gene dosage but also modulate basic mechanisms of gene regulation. SVs can alter the copy number of regulatory elements or modify the 3D genome by disrupting higher-order chromatin organization such as topologically associating domains. As a result of these position effects, SVs can influence the expression of genes distant from the SV breakpoints, thereby causing disease. The impact of SVs on the 3D genome and on gene expression regulation has to be considered when interpreting the pathogenic potential of these variant types.
Collapse
Affiliation(s)
- Malte Spielmann
- Department of Genome Sciences, University of Washington, Seattle, WA, USA
| | - Darío G Lupiáñez
- Epigenetics and Sex Development Group, Berlin Institute for Medical Systems Biology, Max-Delbrück Center for Molecular Medicine, Berlin-Buch, Germany
| | - Stefan Mundlos
- Max Planck Institute for Molecular Genetics, RG Development & Disease, Berlin, Germany. .,Institute for Medical and Human Genetics, Charité Universitätsmedizin Berlin, Berlin, Germany.
| |
Collapse
|
20
|
Bick D, Jones M, Taylor SL, Taft RJ, Belmont J. Case for genome sequencing in infants and children with rare, undiagnosed or genetic diseases. J Med Genet 2019; 56:783-791. [PMID: 31023718 PMCID: PMC6929710 DOI: 10.1136/jmedgenet-2019-106111] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 03/19/2019] [Indexed: 01/01/2023]
Abstract
Up to 350 million people worldwide suffer from a rare disease, and while the individual diseases are rare, in aggregate they represent a substantial challenge to global health systems. The majority of rare disorders are genetic in origin, with children under the age of five disproportionately affected. As these conditions are difficult to identify clinically, genetic and genomic testing have become the backbone of diagnostic testing in this population. In the last 10 years, next-generation sequencing technologies have enabled testing of multiple disease genes simultaneously, ranging from targeted gene panels to exome sequencing (ES) and genome sequencing (GS). GS is quickly becoming a practical first-tier test, as cost decreases and performance improves. A growing number of studies demonstrate that GS can detect an unparalleled range of pathogenic abnormalities in a single laboratory workflow. GS has the potential to deliver unbiased, rapid and accurate molecular diagnoses to patients across diverse clinical indications and complex presentations. In this paper, we discuss clinical indications for testing and historical testing paradigms. Evidence supporting GS as a diagnostic tool is supported by superior genomic coverage, types of pathogenic variants detected, simpler laboratory workflow enabling shorter turnaround times, diagnostic and reanalysis yield, and impact on healthcare.
Collapse
Affiliation(s)
- David Bick
- HudsonAlpha Institute for Biotechnology, Huntsville, Alabama, USA
| | - Marilyn Jones
- Rady Children's Hospital San Diego, San Diego, California, USA
| | | | | | | |
Collapse
|
21
|
Zepeda-Mendoza CJ, Morton CC. The Iceberg under Water: Unexplored Complexity of Chromoanagenesis in Congenital Disorders. Am J Hum Genet 2019; 104:565-577. [PMID: 30951674 DOI: 10.1016/j.ajhg.2019.02.024] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 02/25/2019] [Indexed: 01/16/2023] Open
Abstract
Structural variation, composed of balanced and unbalanced genomic rearrangements, is an important contributor to human genetic diversity with prominent roles in somatic and congenital disease. At the nucleotide level, structural variants (SVs) have been shown to frequently harbor additional breakpoints and copy-number imbalances, a complexity predicted to emerge wholly as a single-cell division event. Chromothripsis, chromoplexy, and chromoanasynthesis, collectively referred to as chromoanagenesis, are three major mechanisms that explain the occurrence of complex germline and somatic SVs. While chromothripsis and chromoplexy have been shown to be key signatures of cancer, chromoanagenesis has been detected in numerous cases of developmental disease and phenotypically normal individuals. Such observations advocate for a deeper study of the polymorphic and pathogenic properties of complex germline SVs, many of which go undetected by traditional clinical molecular and cytogenetic methods. This review focuses on congenital chromoanagenesis, mechanisms leading to occurrence of these complex rearrangements, and their impact on chromosome organization and genome function. We highlight future applications of routine screening of complex and balanced SVs in the clinic, as these represent a potential and often neglected genetic disease source, a true "iceberg under water."
Collapse
Affiliation(s)
- Cinthya J Zepeda-Mendoza
- Division of Laboratory Genetics, Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55902, USA
| | - Cynthia C Morton
- Departments of Obstetrics and Gynecology and of Pathology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA; Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA 02142, USA; Manchester Center for Audiology and Deafness, School of Health Sciences, Manchester Academic Health Science Centre, University of Manchester, Manchester M13 9NT, UK.
| |
Collapse
|
22
|
Cicatiello R, Pignataro P, Izzo A, Mollo N, Pezone L, Maruotti GM, Sarno L, Sglavo G, Conti A, Genesio R, Nitsch L. Chromosomal Microarray Analysis versus Karyotyping in Fetuses with Increased Nuchal Translucency. Med Sci (Basel) 2019; 7:medsci7030040. [PMID: 30818867 PMCID: PMC6473420 DOI: 10.3390/medsci7030040] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2018] [Revised: 02/01/2019] [Accepted: 02/15/2019] [Indexed: 11/26/2022] Open
Abstract
We have carried out a retrospective study of chromosome anomalies associated with increased nuchal translucency (NT) in order to compare yield rates of karyotype, chromosome microarray analysis (CMA), and non-invasive prenatal testing (NIPT) in this condition. Presenting with increased NT or cystic hygroma ≥3.5 mm as an isolated sign, 249 fetuses underwent karyotype and/or CMA from 11 to 18 gestational weeks. Karyotype and fluorescence in situ hybridization (FISH) analyses detected 103 chromosomal anomalies including 95 aneuploidies and eight chromosomal rearrangements or derivatives. Further, seven pathogenic copy number variants (CNV), five likely pathogenic CNVs, and 15 variants of unknown significance (VOUS) were detected by CMA in fetuses with normal karyotype. Genetic testing is now facing new challenges due to results with uncertain clinical impacts. Additional investigations will be necessary to interpret these findings. More than 15% of the anomalies that we have diagnosed with invasive techniques could not be detected by NIPT. It is therefore definitely not recommended in the case of ultrasound anomalies. These results, while corroborating the use of CMA in fetuses with increased NT as a second tier after rapid aneuploidy testing, do not suggest a dismissal of karyotype analysis.
Collapse
Affiliation(s)
- Rita Cicatiello
- Dept. Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Piero Pignataro
- Dept. Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Antonella Izzo
- Dept. Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Nunzia Mollo
- Dept. Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Lucia Pezone
- Dept. Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Giuseppe Maria Maruotti
- Maternal-child Department, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Laura Sarno
- Maternal-child Department, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Gabriella Sglavo
- Maternal-child Department, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Anna Conti
- Dept. Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Rita Genesio
- Dept. Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Lucio Nitsch
- Dept. Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
- Institute of Experimental Endocrinology and Oncology, National Research Council, 80131 Naples, Italy.
| |
Collapse
|
23
|
Abstract
Noncoding DNA sequences play crucial roles in gene regulation, including via three-dimensional genome organization where they define chromatin boundaries and segment the genome into a sequence of insulated neighborhoods. However, the relative importance of noncoding DNA elements, particularly in comparison with protein-coding DNA sequences, remains more poorly characterized. Here, we systematically test if chromatin boundary disruptions are under purifying selection. Our analyses uncover a genomewide depletion of structural variants that would have the potential to alter chromatin structure. This in turn has implications for predicting not only which variants are likely pathogenic in clinical genetics settings, but also which are likely key innovations in primate evolution, and argues for expanding the current gene-centric paradigm for interpreting structural variants. The potential impact of structural variants includes not only the duplication or deletion of coding sequences, but also the perturbation of noncoding DNA regulatory elements and structural chromatin features, including topological domains (TADs). Structural variants disrupting TAD boundaries have been implicated both in cancer and developmental disease; this likely occurs via “enhancer hijacking,” whereby removal of the TAD boundary exposes enhancers to new target transcription start sites (TSSs). With this functional role, we hypothesized that boundaries would display evidence for negative selection. Here we demonstrate that the chromatin landscape constrains structural variation both within healthy humans and across primate evolution. In contrast, in patients with developmental delay, variants occur remarkably uniformly across genomic features, suggesting a potentially broad role for enhancer hijacking in human disease.
Collapse
|
24
|
Tzschach A. X-chromosomale Intelligenzminderung. MED GENET-BERLIN 2018. [DOI: 10.1007/s11825-018-0207-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Zusammenfassung
X-chromosomale Intelligenzminderung („X-linked intellectual disability“, XLID) ist eine heterogene Krankheitsgruppe; inzwischen sind mehr als 100 XLID-Gene identifiziert worden. Das Fragile-X-Syndrom mit CGG-Repeatexpansion in der 5’-UTR des FMR1-Gens ist die häufigste monogene Ursache für Intelligenzminderung. Weitere X‑chromosomale Gene mit vergleichsweise hohen Mutationsprävalenzen sind ATRX, RPS6KA3, GPC3, SLC16A2, SLC6A8 und ARX. Die Ursachen für XLID verteilen sich zu ca. 90 % auf molekulargenetisch nachweisbare Mutationen und zu ca. 10 % auf chromosomale Kopienzahlvarianten („copy-number variants“, CNVs). Häufige CNVs sind Duplikationen in Xq28 unter Einschluss von MECP2 sowie das Xp11.22-Duplikations-Syndrom mit Überexpression von HUWE1. Mit den aktuellen Untersuchungsmethoden kann bei ca. 10 % der männlichen Patienten mit Intelligenzminderung eine X‑chromosomale Ursache nachgewiesen werden. Neue Erkenntnisse zu XLID sind für die nächsten Jahre am ehesten in den nicht kodierenden Regionen zu erwarten, wo wahrscheinlich ein weiterer Teil der Ursachen für das bislang nicht vollständig erklärte Überwiegen männlicher Patienten zu suchen ist.
Collapse
Affiliation(s)
- Andreas Tzschach
- Aff1 0000 0001 2111 7257 grid.4488.0 Institut für Klinische Genetik Technische Universität Dresden Fetscherstr. 74 01307 Dresden Deutschland
| |
Collapse
|
25
|
Affiliation(s)
- David R Adams
- From the Office of the Clinical Director, National Human Genome Research Institute, and the Undiagnosed Diseases Program, National Institutes of Health, Bethesda, MD (D.R.A.); and the Department of Molecular and Human Genetics, Baylor College of Medicine, and Baylor Genetics - both in Houston (C.M.E.)
| | - Christine M Eng
- From the Office of the Clinical Director, National Human Genome Research Institute, and the Undiagnosed Diseases Program, National Institutes of Health, Bethesda, MD (D.R.A.); and the Department of Molecular and Human Genetics, Baylor College of Medicine, and Baylor Genetics - both in Houston (C.M.E.)
| |
Collapse
|
26
|
Krefting J, Andrade-Navarro MA, Ibn-Salem J. Evolutionary stability of topologically associating domains is associated with conserved gene regulation. BMC Biol 2018; 16:87. [PMID: 30086749 PMCID: PMC6091198 DOI: 10.1186/s12915-018-0556-x] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 07/26/2018] [Indexed: 12/18/2022] Open
Abstract
Background The human genome is highly organized in the three-dimensional nucleus. Chromosomes fold locally into topologically associating domains (TADs) defined by increased intra-domain chromatin contacts. TADs contribute to gene regulation by restricting chromatin interactions of regulatory sequences, such as enhancers, with their target genes. Disruption of TADs can result in altered gene expression and is associated to genetic diseases and cancers. However, it is not clear to which extent TAD regions are conserved in evolution and whether disruption of TADs by evolutionary rearrangements can alter gene expression. Results Here, we hypothesize that TADs represent essential functional units of genomes, which are stable against rearrangements during evolution. We investigate this using whole-genome alignments to identify evolutionary rearrangement breakpoints of different vertebrate species. Rearrangement breakpoints are strongly enriched at TAD boundaries and depleted within TADs across species. Furthermore, using gene expression data across many tissues in mouse and human, we show that genes within TADs have more conserved expression patterns. Disruption of TADs by evolutionary rearrangements is associated with changes in gene expression profiles, consistent with a functional role of TADs in gene expression regulation. Conclusions Together, these results indicate that TADs are conserved building blocks of genomes with regulatory functions that are often reshuffled as a whole instead of being disrupted by rearrangements. Electronic supplementary material The online version of this article (10.1186/s12915-018-0556-x) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Jan Krefting
- Faculty of Biology, Johannes Gutenberg University of Mainz, 55128, Mainz, Germany.,Institute of Molecular Biology, 55128, Mainz, Germany
| | - Miguel A Andrade-Navarro
- Faculty of Biology, Johannes Gutenberg University of Mainz, 55128, Mainz, Germany.,Institute of Molecular Biology, 55128, Mainz, Germany
| | - Jonas Ibn-Salem
- Faculty of Biology, Johannes Gutenberg University of Mainz, 55128, Mainz, Germany. .,Institute of Molecular Biology, 55128, Mainz, Germany.
| |
Collapse
|
27
|
Lazar NH, Nevonen KA, O'Connell B, McCann C, O'Neill RJ, Green RE, Meyer TJ, Okhovat M, Carbone L. Epigenetic maintenance of topological domains in the highly rearranged gibbon genome. Genome Res 2018; 28:983-997. [PMID: 29914971 PMCID: PMC6028127 DOI: 10.1101/gr.233874.117] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 06/01/2018] [Indexed: 12/27/2022]
Abstract
The relationship between evolutionary genome remodeling and the three-dimensional structure of the genome remain largely unexplored. Here, we use the heavily rearranged gibbon genome to examine how evolutionary chromosomal rearrangements impact genome-wide chromatin interactions, topologically associating domains (TADs), and their epigenetic landscape. We use high-resolution maps of gibbon–human breaks of synteny (BOS), apply Hi-C in gibbon, measure an array of epigenetic features, and perform cross-species comparisons. We find that gibbon rearrangements occur at TAD boundaries, independent of the parameters used to identify TADs. This overlap is supported by a remarkable genetic and epigenetic similarity between BOS and TAD boundaries, namely presence of CpG islands and SINE elements, and enrichment in CTCF and H3K4me3 binding. Cross-species comparisons reveal that regions orthologous to BOS also correspond with boundaries of large (400–600 kb) TADs in human and other mammalian species. The colocalization of rearrangement breakpoints and TAD boundaries may be due to higher chromatin fragility at these locations and/or increased selective pressure against rearrangements that disrupt TAD integrity. We also examine the small portion of BOS that did not overlap with TAD boundaries and gave rise to novel TADs in the gibbon genome. We postulate that these new TADs generally lack deleterious consequences. Last, we show that limited epigenetic homogenization occurs across breakpoints, irrespective of their time of occurrence in the gibbon lineage. Overall, our findings demonstrate remarkable conservation of chromatin interactions and epigenetic landscape in gibbons, in spite of extensive genomic shuffling.
Collapse
Affiliation(s)
- Nathan H Lazar
- Bioinformatics and Computational Biology Division, Department of Medical Informatics and Clinical Epidemiology, Oregon Health and Science University, Portland, Oregon 97239, USA
| | - Kimberly A Nevonen
- Department of Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon 97239, USA
| | - Brendan O'Connell
- Department of Biomolecular Engineering, University of California, Santa Cruz, California 95064, USA
| | - Christine McCann
- Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269, USA.,Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut 06269, USA
| | - Rachel J O'Neill
- Institute for Systems Genomics, University of Connecticut, Storrs, Connecticut 06269, USA.,Department of Molecular and Cell Biology, University of Connecticut, Storrs, Connecticut 06269, USA
| | - Richard E Green
- Department of Biomolecular Engineering, University of California, Santa Cruz, California 95064, USA
| | - Thomas J Meyer
- Bioinformatics and Computational Biology Division, Department of Medical Informatics and Clinical Epidemiology, Oregon Health and Science University, Portland, Oregon 97239, USA
| | - Mariam Okhovat
- Department of Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon 97239, USA
| | - Lucia Carbone
- Bioinformatics and Computational Biology Division, Department of Medical Informatics and Clinical Epidemiology, Oregon Health and Science University, Portland, Oregon 97239, USA.,Department of Medicine, Knight Cardiovascular Institute, Oregon Health and Science University, Portland, Oregon 97239, USA.,Department of Molecular and Medical Genetics, Oregon Health and Science University, Portland, Oregon 97239, USA.,Oregon National Primate Research Center, Beaverton, Oregon 97006, USA
| |
Collapse
|
28
|
Halgren C, Nielsen NM, Nazaryan-Petersen L, Silahtaroglu A, Collins RL, Lowther C, Kjaergaard S, Frisch M, Kirchhoff M, Brøndum-Nielsen K, Lind-Thomsen A, Mang Y, El-Schich Z, Boring CA, Mehrjouy MM, Jensen PK, Fagerberg C, Krogh LN, Hansen J, Bryndorf T, Hansen C, Talkowski ME, Bak M, Tommerup N, Bache I. Risks and Recommendations in Prenatally Detected De Novo Balanced Chromosomal Rearrangements from Assessment of Long-Term Outcomes. Am J Hum Genet 2018; 102:1090-1103. [PMID: 29805044 DOI: 10.1016/j.ajhg.2018.04.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 04/06/2018] [Indexed: 12/20/2022] Open
Abstract
The 6%-9% risk of an untoward outcome previously established by Warburton for prenatally detected de novo balanced chromosomal rearrangements (BCRs) does not account for long-term morbidity. We performed long-term follow-up (mean 17 years) of a registry-based nationwide cohort of 41 individuals carrying a prenatally detected de novo BCR with normal first trimester screening/ultrasound scan. We observed a significantly higher frequency of neurodevelopmental and/or neuropsychiatric disorders than in a matched control group (19.5% versus 8.3%, p = 0.04), which was increased to 26.8% upon clinical follow-up. Chromosomal microarray of 32 carriers revealed no pathogenic imbalances, illustrating a low prognostic value when fetal ultrasound scan is normal. In contrast, mate-pair sequencing revealed disrupted genes (ARID1B, NPAS3, CELF4), regulatory domains of known developmental genes (ZEB2, HOXC), and complex BCRs associated with adverse outcomes. Seven unmappable autosomal-autosomal BCRs with breakpoints involving pericentromeric/heterochromatic regions may represent a low-risk group. We performed independent phenotype-aware and blinded interpretation, which accurately predicted benign outcomes (specificity = 100%) but demonstrated relatively low sensitivity for prediction of the clinical outcome in affected carriers (sensitivity = 45%-55%). This sensitivity emphasizes the challenges associated with prenatal risk prediction for long-term morbidity in the absence of phenotypic data given the still immature annotation of the morbidity genome and poorly understood long-range regulatory mechanisms. In conclusion, we upwardly revise the previous estimates of Warburton to a morbidity risk of 27% and recommend sequencing of the chromosomal breakpoints as the first-tier diagnostic test in pregnancies with a de novo BCR.
Collapse
|
29
|
Zepeda-Mendoza CJ, Menon S, Morton CC. Computational Prediction of Position Effects of Human Chromosome Rearrangements. CURRENT PROTOCOLS IN HUMAN GENETICS 2018; 97:e57. [PMID: 30038699 PMCID: PMC6054318 DOI: 10.1002/cphg.57] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Balanced and apparently balanced chromosome abnormalities (BCAs) have long been known to generate disease through position effects, either by altering local networks of gene regulation or positioning genes in architecturally different chromosome domains. Despite these observations, identification of distally affected genes by BCAs is oftentimes neglected, especially when predicted gene disruptions are found elsewhere in the genome. In this unit, we provide detailed instructions on how to run a computational pipeline that identifies relevant candidates of non-coding BCA position effects. This methodology facilitates quick identification of genes potentially involved in disease by non-coding BCAs and other types of rearrangements, and expands on the importance of considering the long-range consequences of genomic lesions.
Collapse
Affiliation(s)
- Cinthya J. Zepeda-Mendoza
- Laboratory Genetics and Genomics, Mayo Clinic School of Graduate Medical Education, Mayo Clinic, Rochester, MN 55902, USA
| | - Shreya Menon
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women’s Hospital, Boston, MA 02115, USA
| | - Cynthia C. Morton
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women’s Hospital, Boston, MA 02115, USA,Harvard Medical School, Boston, MA 02115, USA,Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, MA02142, USA,Department of Pathology, Brigham and Women’s Hospital, Boston, MA 02115, USA,Division of Evolution and Genomic Science, School of Biological Sciences, Manchester Academic Health Science Centre, Manchester M13 9NT, UK,Corresponding author
| |
Collapse
|
30
|
McCartney DL, Walker RM, Morris SW, Anderson SM, Duff BJ, Marioni RE, Millar JK, McCarthy SE, Ryan NM, Lawrie SM, Watson AR, Blackwood DHR, Thomson PA, McIntosh AM, McCombie WR, Porteous DJ, Evans KL. Altered DNA methylation associated with a translocation linked to major mental illness. NPJ SCHIZOPHRENIA 2018; 4:5. [PMID: 29555928 PMCID: PMC5859082 DOI: 10.1038/s41537-018-0047-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 02/16/2018] [Accepted: 02/22/2018] [Indexed: 01/03/2023]
Abstract
Recent work has highlighted a possible role for altered epigenetic modifications, including differential DNA methylation, in susceptibility to psychiatric illness. Here, we investigate blood-based DNA methylation in a large family where a balanced translocation between chromosomes 1 and 11 shows genome-wide significant linkage to psychiatric illness. Genome-wide DNA methylation was profiled in whole-blood-derived DNA from 41 individuals using the Infinium HumanMethylation450 BeadChip (Illumina Inc., San Diego, CA). We found significant differences in DNA methylation when translocation carriers (n = 17) were compared to related non-carriers (n = 24) at 13 loci. All but one of the 13 significant differentially methylated positions (DMPs) mapped to the regions surrounding the translocation breakpoints. Methylation levels of five DMPs were associated with genotype at SNPs in linkage disequilibrium with the translocation. Two of the five genes harbouring significant DMPs, DISC1 and DUSP10, have been previously shown to be differentially methylated in schizophrenia. Gene Ontology analysis revealed enrichment for terms relating to neuronal function and neurodevelopment among the genes harbouring the most significant DMPs. Differentially methylated region (DMR) analysis highlighted a number of genes from the MHC region, which has been implicated in psychiatric illness previously through genetic studies. We show that inheritance of a translocation linked to major mental illness is associated with differential DNA methylation at loci implicated in neuronal development/function and in psychiatric illness. As genomic rearrangements are over-represented in individuals with psychiatric illness, such analyses may be valuable more widely in the study of these conditions.
Collapse
Affiliation(s)
- Daniel L McCartney
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Rosie M Walker
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Stewart W Morris
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Susan M Anderson
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Barbara J Duff
- Division of Psychiatry, Royal Edinburgh Hospital, University of Edinburgh, Edinburgh, EH10 5HF, UK
| | - Riccardo E Marioni
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
- Department of Psychology, Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, 7 George Square, Edinburgh, EH8 9JZ, UK
| | - J Kirsty Millar
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Shane E McCarthy
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - Niamh M Ryan
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
| | - Stephen M Lawrie
- Division of Psychiatry, Royal Edinburgh Hospital, University of Edinburgh, Edinburgh, EH10 5HF, UK
| | - Andrew R Watson
- Division of Psychiatry, Royal Edinburgh Hospital, University of Edinburgh, Edinburgh, EH10 5HF, UK
| | - Douglas H R Blackwood
- Division of Psychiatry, Royal Edinburgh Hospital, University of Edinburgh, Edinburgh, EH10 5HF, UK
| | - Pippa A Thomson
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
- Department of Psychology, Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, 7 George Square, Edinburgh, EH8 9JZ, UK
| | - Andrew M McIntosh
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
- Division of Psychiatry, Royal Edinburgh Hospital, University of Edinburgh, Edinburgh, EH10 5HF, UK
- Department of Psychology, Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, 7 George Square, Edinburgh, EH8 9JZ, UK
| | - W Richard McCombie
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | - David J Porteous
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK
- Department of Psychology, Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, 7 George Square, Edinburgh, EH8 9JZ, UK
| | - Kathryn L Evans
- Medical Genetics Section, Centre for Genomic and Experimental Medicine, Institute of Genetics and Molecular Medicine, Western General Hospital, University of Edinburgh, Crewe Road, Edinburgh, EH4 2XU, UK.
- Department of Psychology, Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, 7 George Square, Edinburgh, EH8 9JZ, UK.
| |
Collapse
|
31
|
Dong Z, Ye L, Yang Z, Chen H, Yuan J, Wang H, Guo X, Li Y, Wang J, Chen F, Cheung SW, Morton CC, Jiang H, Choy KW. Balanced Chromosomal Rearrangement Detection by Low-Pass Whole-Genome Sequencing. ACTA ACUST UNITED AC 2018; 96:8.18.1-8.18.16. [PMID: 29364520 DOI: 10.1002/cphg.51] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Balanced chromosomal rearrangements (or balanced chromosome abnormalities, BCAs) are common chromosomal structural variants. Emerging studies have demonstrated the feasibility of using whole-genome sequencing (WGS) for detection of BCA-associated breakpoints, but the requirement for a priori knowledge of the rearranged regions from G-banded chromosome analysis limits its application. The protocols described here are based on low-pass WGS for detecting BCA events independent from chromosome analysis, and has been validated using genomic data from the 1000 Genomes Project. This approach adopts non-size-selected mate-pair library (3∼8 kb) with 2∼3 μg DNA as input, and requires only 30 million read-pairs (50 bp, equivalent to 1-fold base-coverage) for each sample. The complete procedure takes 13 days and the total cost is estimated to be less than $600 (USD) per sample. © 2018 by John Wiley & Sons, Inc.
Collapse
Affiliation(s)
- Zirui Dong
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong, China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China.,BGI-Shenzhen, Shenzhen, China
| | - Lingfei Ye
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China
| | - Zhenjun Yang
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China.,School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Haixiao Chen
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China
| | - Jianying Yuan
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China
| | - Huilin Wang
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong, China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China.,Department of Central Laboratory, Bao'an Maternity and Child Healthcare Hospital, Jinan University School of Medicine, Key Laboratory of Birth Defects Research, Birth Defects Prevention Research and Transformation Team, Shenzhen, China
| | - Xiaosen Guo
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China
| | - Yun Li
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China
| | - Jun Wang
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China
| | - Fang Chen
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China
| | - Sau Wai Cheung
- The Chinese University of Hong Kong-Baylor College of Medicine Joint Center for Medical Genetics, Hong Kong, China.,Department of Molecular and Human Genetics, Baylor College of Medicine Houston, Texas
| | - Cynthia C Morton
- Departments of Pathology and of Obstetrics and Gynecology, Brigham and Women's Hospital, Boston, Massachusetts.,Harvard Medical School, Boston, Massachusetts.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, Massachusetts.,Division of Evolution and Genomic Sciences, School of Biological Sciences, University of Manchester, Manchester Academic Health Science Center, Manchester, United Kingdom
| | - Hui Jiang
- BGI-Shenzhen, Shenzhen, China.,China National Genebank-Shenzhen, BGI-Shenzhen, Shenzhen, China
| | - Kwong Wai Choy
- Department of Obstetrics and Gynaecology, The Chinese University of Hong Kong, Hong Kong, China.,Shenzhen Research Institute, The Chinese University of Hong Kong, Shenzhen, China.,The Chinese University of Hong Kong-Baylor College of Medicine Joint Center for Medical Genetics, Hong Kong, China
| |
Collapse
|
32
|
David D, Anand D, Araújo C, Gloss B, Fino J, Dinger M, Lindahl P, Pöyhönen M, Hannele L, Lavinha J. Identification of OAF and PVRL1 as candidate genes for an ocular anomaly characterized by Peters anomaly type 2 and ectopia lentis. Exp Eye Res 2018; 168:161-170. [PMID: 29305299 DOI: 10.1016/j.exer.2017.12.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 12/21/2017] [Accepted: 12/27/2017] [Indexed: 01/10/2023]
Abstract
Keratolenticular dysgenesis (KLD) and ectopia lentis are congenital eye defects. The aim of this study is the identification of molecular genetic alterations responsible for those ocular anomalies with neurologic impairment in an individual with a de novo balanced chromosome translocation t(11;18)(q23.3;q11.2)dn. Disruption of OAF, the human orthologue of the Drosophila oaf, by the 11q23.3 breakpoint results in reduced expression of this transcriptional regulator. Furthermore, four most likely nonfunctional chimeric transcripts comprising up to OAF exon 3, derived from the der(11) allele, have also been identified. This locus has been implicated by publicly available genome-wide association data in corneal disease and corneal topography. The expression of the poliovirus receptor-related 1(PVRL1) or nectin cell adhesion molecule 1 (NECTIN1), a paralogue of nectin cell adhesion molecule 3 (PVRL3) associated with congenital ocular defects, situated 500 kb upstream from 11q23.3 breakpoint, is increased. The 18q11.2 breakpoint is localized between cutaneous T-cell lymphoma-associated antigen 1(CTAGE1) and retinoblastoma binding protein 8 (RBBP8) genes. Genomic imbalance that could contribute to the observed phenotype was excluded. Analysis of gene expression datasets throughout normal murine ocular lens embryogenesis suggests that OAF expression is significantly enriched in the lens from early stages of development through adulthood, whereas PVRL1 is lens-enriched until E12.5 and then down-regulated. This contrasts with the observation that the proposita's lymphoblastoid cell lines exhibit low OAF and high PVRL1 expression as compared to control, which offers further support that the alterations described above are most likely responsible for the clinical phenotype. Finally, gene interaction topology data for PVRL1 also agree with our proposal that disruption of OAF by the translocation breakpoint and misregulation of PVRL1 due to a position effect contribute to the observed ocular and neurological phenotype.
Collapse
Affiliation(s)
- Dezső David
- Department of Human Genetics, National Health Institute Doutor Ricardo Jorge, Lisbon, Portugal.
| | - Deepti Anand
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Carlos Araújo
- Department of Human Genetics, National Health Institute Doutor Ricardo Jorge, Lisbon, Portugal
| | - Brian Gloss
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Darlinghurst, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW, Kensington, Australia
| | - Joana Fino
- Department of Human Genetics, National Health Institute Doutor Ricardo Jorge, Lisbon, Portugal
| | - Marcel Dinger
- Genomics and Epigenetics Division, Garvan Institute of Medical Research, Darlinghurst, Australia; St Vincent's Clinical School, Faculty of Medicine, UNSW, Kensington, Australia
| | - Päivi Lindahl
- Ophthalmology, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Minna Pöyhönen
- Clinical Genetics, University of Helsinki and Helsinki University Hospital, Helsinki, Finland
| | - Laivuori Hannele
- Medical and Clinical Genetics, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Institute for Molecular Medicine Finland, University of Helsinki, Helsinki, Finland
| | - João Lavinha
- Department of Human Genetics, National Health Institute Doutor Ricardo Jorge, Lisbon, Portugal
| |
Collapse
|
33
|
Historical and Clinical Perspectives on Chromosomal Translocations. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1044:1-14. [PMID: 29956287 DOI: 10.1007/978-981-13-0593-1_1] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Chromosomal translocations, rearrangements involving the exchange of segments between chromosomes, were documented in humans in 1959. The first accurately reported clinical phenotype resulting from a translocation was that of Down syndrome. In a small percentage of Down syndrome cases, an extra 21q is provided by a Robertsonian translocation chromosome, either occurring de novo or inherited from a phenotypically normal parent with the translocation chromosome and a balanced genome of 45 chromosomes. Balanced translocations, including both Robertsonian and reciprocal translocations, are typically benign, but meiosis in germ cells with balanced translocations may result in meiotic arrest and subsequent infertility, or in unbalanced gametes, with attendant risks of miscarriage and unbalanced progeny. Most reciprocal translocations are unique. A few to several percent of translocations disrupt haploinsufficient genes or their regulatory regions and result in clinical phenotypes. Balanced translocations from patients with clinical phenotypes have been valuable in mapping disease genes and in illuminating cis-regulatory regions. Mapping of discordant mate pairs from long-insert, low-pass genome sequencing now permits efficient and cost-effective discovery and nucleotide-level resolution of rearrangement breakpoints, information that is absolutely necessary for interpreting the etiology of clinical phenotypes in patients with rearrangements. Pathogenic translocations and other balanced chromosomal rearrangements constitute a class of typically highly penetrant mutation that is cryptic to both clinical microarray and exome sequencing. A significant proportion of rearrangements include additional complexity that is not visible by conventional karyotype analysis. Some proportion of patients with negative findings on exome/genome sequencing and clinical microarray will be found to have etiologic balanced rearrangements only discoverable by genome sequencing with analysis pipelines optimized to recover rearrangement breakpoints.
Collapse
|
34
|
Regulatory variants of FOXG1 in the context of its topological domain organisation. Eur J Hum Genet 2017; 26:186-196. [PMID: 29289958 DOI: 10.1038/s41431-017-0011-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 08/28/2017] [Accepted: 08/31/2017] [Indexed: 02/02/2023] Open
Abstract
FOXG1 syndrome is caused by FOXG1 intragenic point mutations, or by long-range position effects (LRPE) of intergenic structural variants. However, the size of the FOXG1 regulatory landscape is uncertain, because the associated topologically associating domain (TAD) in fibroblasts is split into two domains in embryonic stem cells (hESC). Indeed, it has been suggested that the pathogenetic mechanism of deletions that remove the stem-cell-specific TAD boundary may be enhancer adoption due to ectopic activity of enhancer(s) located in the distal hESC-TAD. Herein we map three de novo translocation breakpoints to the proximal regulatory domain of FOXG1. The classical FOXG1 syndrome in these and in other translocation patients, and in a patient with an intergenic deletion that removes the hESC-specific TAD boundary, do not support the hypothesised enhancer adoption as a main contributor to the FOXG1 syndrome. Also, virtual 4 C and HiC-interaction data suggest that the hESC-specific TAD boundary may not be critical for FOXG1 regulation in a majority of human cells and tissues, including brain tissues and a neuronal progenitor cell line. Our data support the importance of a critical regulatory region (SRO) proximal to the hESC-specific TAD boundary. We further narrow this critical region by a deletion distal to the hESC-specific boundary, associated with a milder clinical phenotype. The distance from FOXG1 to the SRO ( > 500 kb) highlight a limitation of ENCODE DNase hypersensitivity data for functional prediction of LRPE. Moreover, the SRO has little overlap with a cluster of frequently associating regions (FIREs) located in the proximal hESC-TAD.
Collapse
|
35
|
Schilit SLP, Morton CC. 3C-PCR: a novel proximity ligation-based approach to phase chromosomal rearrangement breakpoints with distal allelic variants. Hum Genet 2017; 137:55-62. [PMID: 29196799 DOI: 10.1007/s00439-017-1853-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2017] [Accepted: 11/11/2017] [Indexed: 01/07/2023]
Abstract
Recent advances in molecular cytogenetics highlight the importance of noncoding structural variation in human disease. Genomic rearrangements can disrupt chromatin architecture, leading to long-range alterations in gene expression. With increasing ability to assess distal gene dysregulation comes new challenges in clinical interpretation of rearrangements. While haplotyping methods to determine compound heterozygosity in a single gene with two pathogenic variants are established, such methods are insufficient for phasing larger distances between a pathogenic variant and a genomic rearrangement breakpoint. Herein, we present an inexpensive and efficient proximity ligation-based method called 3C-PCR for phasing chromosomal rearrangement breakpoints with distal allelic variants. 3C-PCR uses canonical chromosome conformation capture (3C) libraries for targeted distal phasing by implementing a novel nested PCR strategy with primers anchored across the rearrangement breakpoints and subsequent Sanger sequencing. As a proof of concept, 3C-PCR was used to phase a highly variable region 1.3 Mb upstream of a chromosomal rearrangement breakpoint in a balanced translocation. We found that the nested PCR approach amplified the derivative chromosome substrate exclusively and identified the same haplotype by Sanger sequencing reliably. Given its efficacy and versatility, 3C-PCR is ideal for use in phasing chromosomal rearrangement breakpoints with allelic variants located at a genomic distance over a megabase.
Collapse
Affiliation(s)
- Samantha L P Schilit
- Biological and Biomedical Sciences Program, Graduate School of Arts and Sciences, Harvard University, Cambridge, MA, USA
- Program in Genetics and Genomics, Department of Genetics, Harvard Medical School, Boston, MA, USA
- Leder Human Biology and Translational Medicine Program, Division of Medical Sciences, Harvard Medical School, Boston, MA, USA
| | - Cynthia C Morton
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA, USA.
- Division of Evolution and Genomic Science, School of Biological Sciences, Manchester Academic Health Science Centre, Manchester, UK.
- Departments of Obstetrics and Gynecology and of Pathology, Brigham and Women's Hospital and Harvard Medical School, New Research Building, Room 160D, 77 Avenue Louis Pasteur, Boston, MA, 02115, USA.
| |
Collapse
|