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Xu Z, Li Q, Marchionni L, Wang K. PhenoSV: interpretable phenotype-aware model for the prioritization of genes affected by structural variants. Nat Commun 2023; 14:7805. [PMID: 38016949 PMCID: PMC10684511 DOI: 10.1038/s41467-023-43651-y] [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: 06/05/2023] [Accepted: 11/15/2023] [Indexed: 11/30/2023] Open
Abstract
Structural variants (SVs) represent a major source of genetic variation associated with phenotypic diversity and disease susceptibility. While long-read sequencing can discover over 20,000 SVs per human genome, interpreting their functional consequences remains challenging. Existing methods for identifying disease-related SVs focus on deletion/duplication only and cannot prioritize individual genes affected by SVs, especially for noncoding SVs. Here, we introduce PhenoSV, a phenotype-aware machine-learning model that interprets all major types of SVs and genes affected. PhenoSV segments and annotates SVs with diverse genomic features and employs a transformer-based architecture to predict their impacts under a multiple-instance learning framework. With phenotype information, PhenoSV further utilizes gene-phenotype associations to prioritize phenotype-related SVs. Evaluation on extensive human SV datasets covering all SV types demonstrates PhenoSV's superior performance over competing methods. Applications in diseases suggest that PhenoSV can determine disease-related genes from SVs. A web server and a command-line tool for PhenoSV are available at https://phenosv.wglab.org .
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Affiliation(s)
- Zhuoran Xu
- Graduate Group in Genomics and Computational Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, 19104, USA
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Quan Li
- Princess Margaret Cancer Centre, University Health Network, University of Toronto, Toronto, ON, M5G2C1, Canada
| | - Luigi Marchionni
- Department of Pathology and Laboratory Medicine, Weill Cornell Medicine, New York, NY, 10065, USA
| | - Kai Wang
- Raymond G. Perelman Center for Cellular and Molecular Therapeutics, Children's Hospital of Philadelphia, Philadelphia, PA, 19104, USA.
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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2
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Shankar P, Villeneuve DL. AOP Report: Aryl Hydrocarbon Receptor Activation Leads to Early-Life Stage Mortality via Sox9 Repression-Induced Craniofacial and Cardiac Malformations. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2023; 42:2063-2077. [PMID: 37341548 PMCID: PMC10772968 DOI: 10.1002/etc.5699] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 06/15/2023] [Indexed: 06/22/2023]
Abstract
The aryl hydrocarbon receptors (Ahrs) are evolutionarily conserved ligand-dependent transcription factors that are activated by structurally diverse endogenous compounds as well as environmental chemicals such as polycyclic aromatic hydrocarbons and halogenated aromatic hydrocarbons. Activation of the Ahr leads to several transcriptional changes that can cause developmental toxicity resulting in mortality. Evidence was assembled and evaluated for two novel adverse outcome pathways (AOPs) which describe how Ahr activation (molecular initiating event) can lead to early-life stage mortality (adverse outcome), via either SOX9-mediated craniofacial malformations (AOP 455) or cardiovascular toxicity (AOP 456). Using a key event relationship (KER)-by-KER approach, we collected evidence using both a narrative search and a systematic review based on detailed search terms. Weight of evidence for each KER was assessed to inform overall confidence of the AOPs. The AOPs link to previous descriptions of Ahr activation and connect them to two novel key events (KEs), increase in slincR expression, a newly characterized long noncoding RNA with regulatory functions, and suppression of SOX9, a critical transcription factor implicated in chondrogenesis and cardiac development. In general, confidence levels for KERs ranged between medium and strong, with few inconsistencies, as well as several opportunities for future research identified. While the majority of KEs have only been demonstrated in zebrafish with 2,3,7,8-tetrachlorodibenzo-p-dioxin as an Ahr activator, evidence suggests that the two AOPs likely apply to most vertebrates and many Ahr-activating chemicals. Addition of the AOPs into the AOP-Wiki (https://aopwiki.org/) helps expand the growing Ahr-related AOP network to 19 individual AOPs, of which six are endorsed or in progress and the remaining 13 relatively underdeveloped. Environ Toxicol Chem 2023;42:2063-2077. © 2023 SETAC. This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.
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Affiliation(s)
- Prarthana Shankar
- Great Lakes Toxicology and Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA
- University of Wisconsin Madison Sea Grant Fellow at Great Lakes Toxicology and Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA
| | - Daniel L. Villeneuve
- Great Lakes Toxicology and Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA
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3
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Selleri L, Rijli FM. Shaping faces: genetic and epigenetic control of craniofacial morphogenesis. Nat Rev Genet 2023; 24:610-626. [PMID: 37095271 DOI: 10.1038/s41576-023-00594-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/14/2023] [Indexed: 04/26/2023]
Abstract
Major differences in facial morphology distinguish vertebrate species. Variation of facial traits underlies the uniqueness of human individuals, and abnormal craniofacial morphogenesis during development leads to birth defects that significantly affect quality of life. Studies during the past 40 years have advanced our understanding of the molecular mechanisms that establish facial form during development, highlighting the crucial roles in this process of a multipotent cell type known as the cranial neural crest cell. In this Review, we discuss recent advances in multi-omics and single-cell technologies that enable genes, transcriptional regulatory networks and epigenetic landscapes to be closely linked to the establishment of facial patterning and its variation, with an emphasis on normal and abnormal craniofacial morphogenesis. Advancing our knowledge of these processes will support important developments in tissue engineering, as well as the repair and reconstruction of the abnormal craniofacial complex.
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Affiliation(s)
- Licia Selleri
- Program in Craniofacial Biology, Department of Orofacial Sciences, School of Dentistry, University of California, San Francisco, CA, USA.
- Department of Anatomy, School of Medicine, University of California, San Francisco, CA, USA.
| | - Filippo M Rijli
- Laboratory of Developmental Neuroepigenetics, Friedrich Miescher Institute for Biomedical Research, Basel, Switzerland.
- University of Basel, Basel, Switzerland.
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4
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Marincak Vrankova Z, Krivanek J, Danek Z, Zelinka J, Brysova A, Izakovicova Holla L, Hartsfield JK, Borilova Linhartova P. Candidate genes for obstructive sleep apnea in non-syndromic children with craniofacial dysmorphisms - a narrative review. Front Pediatr 2023; 11:1117493. [PMID: 37441579 PMCID: PMC10334820 DOI: 10.3389/fped.2023.1117493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 06/06/2023] [Indexed: 07/15/2023] Open
Abstract
Pediatric obstructive sleep apnea (POSA) is a complex disease with multifactorial etiopathogenesis. The presence of craniofacial dysmorphisms influencing the patency of the upper airway is considered a risk factor for POSA development. The craniofacial features associated with sleep-related breathing disorders (SRBD) - craniosynostosis, retrognathia and micrognathia, midface and maxillary hypoplasia - have high heritability and, in a less severe form, could be also found in non-syndromic children suffering from POSA. As genetic factors play a role in both POSA and craniofacial dysmorphisms, we hypothesize that some genes associated with specific craniofacial features that are involved in the development of the orofacial area may be also considered candidate genes for POSA. The genetic background of POSA in children is less explored than in adults; so far, only one genome-wide association study for POSA has been conducted; however, children with craniofacial disorders were excluded from that study. In this narrative review, we discuss syndromes that are commonly associated with severe craniofacial dysmorphisms and a high prevalence of sleep-related breathing disorders (SRBD), including POSA. We also summarized information about their genetic background and based on this, proposed 30 candidate genes for POSA affecting craniofacial development that may play a role in children with syndromes, and identified seven of these genes that were previously associated with craniofacial features risky for POSA development in non-syndromic children. The evidence-based approach supports the proposition that variants of these candidate genes could lead to POSA phenotype even in these children, and, thus, should be considered in future research in the general pediatric population.
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Affiliation(s)
- Zuzana Marincak Vrankova
- Clinic of Stomatology, Institution Shared with St. Anne's University Hospital, Faculty of Medicine, Masaryk University, Brno, Czech Republic
- Clinic of Maxillofacial Surgery, Institution Shared with the University Hospital Brno, Faculty of Medicine, Masaryk University, Brno, Czech Republic
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
| | - Jan Krivanek
- Department of Histology and Embryology, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Zdenek Danek
- Clinic of Maxillofacial Surgery, Institution Shared with the University Hospital Brno, Faculty of Medicine, Masaryk University, Brno, Czech Republic
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
| | - Jiri Zelinka
- Clinic of Maxillofacial Surgery, Institution Shared with the University Hospital Brno, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Alena Brysova
- Clinic of Stomatology, Institution Shared with St. Anne's University Hospital, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - Lydie Izakovicova Holla
- Clinic of Stomatology, Institution Shared with St. Anne's University Hospital, Faculty of Medicine, Masaryk University, Brno, Czech Republic
| | - James K. Hartsfield
- E. Preston Hicks Professor of Orthodontics and Oral Health Research, University of Kentucky Center for the Biologic Basis of Oral/Systemic Diseases, Hereditary Genetics/Genomics Core, Lexington, KE, United States
| | - Petra Borilova Linhartova
- Clinic of Stomatology, Institution Shared with St. Anne's University Hospital, Faculty of Medicine, Masaryk University, Brno, Czech Republic
- Clinic of Maxillofacial Surgery, Institution Shared with the University Hospital Brno, Faculty of Medicine, Masaryk University, Brno, Czech Republic
- RECETOX, Faculty of Science, Masaryk University, Kotlarska 2, Brno, Czech Republic
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5
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Chen LF, Long HK, Park M, Swigut T, Boettiger AN, Wysocka J. Structural elements promote architectural stripe formation and facilitate ultra-long-range gene regulation at a human disease locus. Mol Cell 2023; 83:1446-1461.e6. [PMID: 36996812 DOI: 10.1016/j.molcel.2023.03.009] [Citation(s) in RCA: 20] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 02/15/2023] [Accepted: 03/07/2023] [Indexed: 03/31/2023]
Abstract
Enhancer clusters overlapping disease-associated mutations in Pierre Robin sequence (PRS) patients regulate SOX9 expression at genomic distances over 1.25 Mb. We applied optical reconstruction of chromatin architecture (ORCA) imaging to trace 3D locus topology during PRS-enhancer activation. We observed pronounced changes in locus topology between cell types. Subsequent analysis of single-chromatin fiber traces revealed that these ensemble-average differences arise through changes in the frequency of commonly sampled topologies. We further identified two CTCF-bound elements, internal to the SOX9 topologically associating domain, which promote stripe formation, are positioned near the domain's 3D geometric center, and bridge enhancer-promoter contacts in a series of chromatin loops. Ablation of these elements results in diminished SOX9 expression and altered domain-wide contacts. Polymer models with uniform loading across the domain and frequent cohesin collisions recapitulate this multi-loop, centrally clustered geometry. Together, we provide mechanistic insights into architectural stripe formation and gene regulation over ultra-long genomic ranges.
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Affiliation(s)
- Liang-Fu Chen
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Hannah Katherine Long
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Minhee Park
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Tomek Swigut
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Alistair Nicol Boettiger
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA.
| | - Joanna Wysocka
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94305, USA.
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6
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Chen Q, Dai J, Bian Q. Integration of 3D genome topology and local chromatin features uncovers enhancers underlying craniofacial-specific cartilage defects. SCIENCE ADVANCES 2022; 8:eabo3648. [PMID: 36417512 PMCID: PMC9683718 DOI: 10.1126/sciadv.abo3648] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Aberrations in tissue-specific enhancers underlie many developmental defects. Disrupting a noncoding region distal from the human SOX9 gene causes the Pierre Robin sequence (PRS) characterized by the undersized lower jaw. Such a craniofacial-specific defect has been previously linked to enhancers transiently active in cranial neural crest cells (CNCCs). We demonstrate that the PRS region also strongly regulates Sox9 in CNCC-derived Meckel's cartilage (MC), but not in limb cartilages, even after decommissioning of CNCC enhancers. Such an MC-specific regulatory effect correlates with the MC-specific chromatin contacts between the PRS region and Sox9, highlighting the importance of lineage-dependent chromatin topology in instructing enhancer usage. By integrating the enhancer signatures and chromatin topology, we uncovered >10,000 enhancers that function differentially between MC and limb cartilages and demonstrated their association with human diseases. Our findings provide critical insights for understanding the choreography of gene regulation during development and interpreting the genetic basis of craniofacial pathologies.
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Affiliation(s)
- Qiming Chen
- Department of Oral and Cranio-maxillofacial Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases; Shanghai Key Laboratory of Stomatology, Shanghai, 200011, China
| | - Jiewen Dai
- Department of Oral and Cranio-maxillofacial Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases; Shanghai Key Laboratory of Stomatology, Shanghai, 200011, China
- Shanghai University of Medicine and Health Sciences, Shanghai, 201318, China
- Corresponding author. (J.D.); (Q.B.)
| | - Qian Bian
- Department of Oral and Cranio-maxillofacial Surgery, Shanghai Ninth People’s Hospital, Shanghai Jiao Tong University School of Medicine, College of Stomatology, Shanghai Jiao Tong University, National Center for Stomatology, National Clinical Research Center for Oral Diseases; Shanghai Key Laboratory of Stomatology, Shanghai, 200011, China
- Shanghai Institute of Precision Medicine, Shanghai, 200125, China
- Shanghai Key Laboratory of Reproductive Medicine, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
- Corresponding author. (J.D.); (Q.B.)
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7
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Ming Z, Vining B, Bagheri-Fam S, Harley V. SOX9 in organogenesis: shared and unique transcriptional functions. Cell Mol Life Sci 2022; 79:522. [PMID: 36114905 PMCID: PMC9482574 DOI: 10.1007/s00018-022-04543-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Revised: 08/13/2022] [Accepted: 08/31/2022] [Indexed: 11/28/2022]
Abstract
The transcription factor SOX9 is essential for the development of multiple organs including bone, testis, heart, lung, pancreas, intestine and nervous system. Mutations in the human SOX9 gene led to campomelic dysplasia, a haploinsufficiency disorder with several skeletal malformations frequently accompanied by 46, XY sex reversal. The mechanisms underlying the diverse SOX9 functions during organ development including its post-translational modifications, the availability of binding partners, and tissue-specific accessibility to target gene chromatin. Here we summarize the expression, activities, and downstream target genes of SOX9 in molecular genetic pathways essential for organ development, maintenance, and function. We also provide an insight into understanding the mechanisms that regulate the versatile roles of SOX9 in different organs.
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Affiliation(s)
- Zhenhua Ming
- Sex Development Laboratory, Hudson Institute of Medical Research, PO Box 5152, Melbourne, VIC, 3168, Australia
- Department of Molecular and Translational Science, Monash University, Melbourne, VIC, 3800, Australia
| | - Brittany Vining
- Sex Development Laboratory, Hudson Institute of Medical Research, PO Box 5152, Melbourne, VIC, 3168, Australia
- Department of Molecular and Translational Science, Monash University, Melbourne, VIC, 3800, Australia
| | - Stefan Bagheri-Fam
- Sex Development Laboratory, Hudson Institute of Medical Research, PO Box 5152, Melbourne, VIC, 3168, Australia
- Department of Molecular and Translational Science, Monash University, Melbourne, VIC, 3800, Australia
| | - Vincent Harley
- Sex Development Laboratory, Hudson Institute of Medical Research, PO Box 5152, Melbourne, VIC, 3168, Australia.
- Department of Molecular and Translational Science, Monash University, Melbourne, VIC, 3800, Australia.
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8
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van Heyningen V. A Journey Through Genetics to Biology. Annu Rev Genomics Hum Genet 2022; 23:1-27. [PMID: 35567277 DOI: 10.1146/annurev-genom-010622-095109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Although my engagement with human genetics emerged gradually, and sometimes serendipitously, it has held me spellbound for decades. Without my teachers, students, postdocs, colleagues, and collaborators, I would not be writing this review of my scientific adventures. Early gene and disease mapping was a satisfying puzzle-solving exercise, but building biological insight was my main goal. The project trajectory was hugely influenced by the evolutionarily conserved nature of the implicated genes and by the pace of progress in genetic technologies. The rich detail of clinical observations, particularly in eye disease, makes humans an excellent model, especially when complemented by the use of multiple other animal species for experimental validation. The contributions of collaborators and rivals also influenced our approach. We are very fortunate to work in this era of unprecedented progress in genetics and genomics. Expected final online publication date for the Annual Review of Genomics and Human Genetics, Volume 23 is October 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Veronica van Heyningen
- UCL Institute of Ophthalmology, University College London, London, United Kingdom.,MRC Human Genetics Unit, Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, United Kingdom;
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9
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Classification of non-coding variants with high pathogenic impact. PLoS Genet 2022; 18:e1010191. [PMID: 35486646 PMCID: PMC9094564 DOI: 10.1371/journal.pgen.1010191] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2021] [Revised: 05/11/2022] [Accepted: 04/05/2022] [Indexed: 01/22/2023] Open
Abstract
Whole genome sequencing is increasingly used to diagnose medical conditions of genetic origin. While both coding and non-coding DNA variants contribute to a wide range of diseases, most patients who receive a WGS-based diagnosis today harbour a protein-coding mutation. Functional interpretation and prioritization of non-coding variants represents a persistent challenge, and disease-causing non-coding variants remain largely unidentified. Depending on the disease, WGS fails to identify a candidate variant in 20–80% of patients, severely limiting the usefulness of sequencing for personalised medicine. Here we present FINSURF, a machine-learning approach to predict the functional impact of non-coding variants in regulatory regions. FINSURF outperforms state-of-the-art methods, owing in particular to optimized control variants selection during training. In addition to ranking candidate variants, FINSURF breaks down the score for each variant into contributions from individual annotations, facilitating the evaluation of their functional relevance. We applied FINSURF to a diverse set of 30 diseases with described causative non-coding mutations, and correctly identified the disease-causative non-coding variant within the ten top hits in 22 cases. FINSURF is implemented as an online server to as well as custom browser tracks, and provides a quick and efficient solution to prioritize candidate non-coding variants in realistic clinical settings.
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10
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Sood A, Shamim U, Kharbanda OP, Kabra M, Gupta N, Mathur A, Joshi A, Parveen S, Zahra S, Sharma P, Seth M, Khan A, Faruq M, Mishra D. Next Generation Sequencing and Cytogenetic Based Evaluation of Indian Pierre Robin Sequence Families Reveals CNV Regions of Modest Effect and a Novel LOXL3 Mutation. Cleft Palate Craniofac J 2021; 59:1329-1339. [PMID: 34787502 DOI: 10.1177/10556656211052781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Pierre Robin Sequence (PRS) affects approximately 1 per 8500 to 14000 new-borns worldwide. Although the clinical entity is well defined, the pathogenesis of PRS is debated. The present study aims to understand the contribution of genomic imbalances and genetic variants in patients clinically diagnosed of PRS. METHODOLOGY A total of 7 independent patients with nonsyndromic PRS thoroughly evaluated by a medical geneticist at a tertiary care hospital, were included in the study. Blood samples were collected from these patients and their family members. Array CGH was performed on all 7 patients and their respective family members for detection of underlying cytogenetic defects. Whole exome sequencing (WES) was performed for 5 families to capture single nucleotide variants or small indels. RESULTS Cytogenetic analyses did not detect any previously reported gross chromosomal aberrations for PRS in the patient cohort. However, copy number variations (CNVs) of size <1 Mb were detected in patients which may have implications in PRS. The present study provided evidence for the occurrence of de novo deletions at 7p14.1 locus in PRS patients: further validating the candidate loci susceptibility in oral clefts. WES data identified LOXL3 as candidate gene, carrying novel deleterious variant, which is suggestive of the role of point mutations in the pathogenesis of PRS. CONCLUSION The present study offered considerable insight into the contribution of cytogenetic defects and novel point mutation in the etiology of nonsyndromic PRS. Studies comprising large number of cases are required to fully elucidate the genetic mechanisms underlying the PRS phenotype.
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Affiliation(s)
- Anubhuti Sood
- Centre for Dental Education and Research, 28730All India Institute of Medical Sciences, Delhi, India
| | - Uzma Shamim
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Om P Kharbanda
- Centre for Dental Education and Research, 28730All India Institute of Medical Sciences, Delhi, India
| | | | - Neerja Gupta
- 28730All India Institute of Medical Sciences, Delhi, India
| | - Aradhana Mathur
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Aditi Joshi
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Shaista Parveen
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Sana Zahra
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Pooja Sharma
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Malika Seth
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Afreen Khan
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Mohammed Faruq
- Genomics and Molecular Medicine, 28840CSIR-Institute of Genomics and Integrative Biology, Delhi, India
| | - Deepika Mishra
- Centre for Dental Education and Research, 28730All India Institute of Medical Sciences, Delhi, India
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11
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Marí-Beffa M, Mesa-Román AB, Duran I. Zebrafish Models for Human Skeletal Disorders. Front Genet 2021; 12:675331. [PMID: 34490030 PMCID: PMC8418114 DOI: 10.3389/fgene.2021.675331] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/08/2021] [Indexed: 12/17/2022] Open
Abstract
In 2019, the Nosology Committee of the International Skeletal Dysplasia Society provided an updated version of the Nosology and Classification of Genetic Skeletal Disorders. This is a reference list of recognized diseases in humans and their causal genes published to help clinician diagnosis and scientific research advances. Complementary to mammalian models, zebrafish has emerged as an interesting species to evaluate chemical treatments against these human skeletal disorders. Due to its versatility and the low cost of experiments, more than 80 models are currently available. In this article, we review the state-of-art of this “aquarium to bedside” approach describing the models according to the list provided by the Nosology Committee. With this, we intend to stimulate research in the appropriate direction to efficiently meet the actual needs of clinicians under the scope of the Nosology Committee.
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Affiliation(s)
- Manuel Marí-Beffa
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, University of Málaga, IBIMA, Málaga, Spain.,Networking Biomedical Research Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Andalusian Centre for Nanomedicine and Biotechnology-BIONAND, Málaga, Spain
| | - Ana B Mesa-Román
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, University of Málaga, IBIMA, Málaga, Spain
| | - Ivan Duran
- Department of Cell Biology, Genetics and Physiology, Faculty of Sciences, University of Málaga, IBIMA, Málaga, Spain.,Networking Biomedical Research Center in Bioengineering, Biomaterials and Nanomedicine (CIBER-BBN), Andalusian Centre for Nanomedicine and Biotechnology-BIONAND, Málaga, Spain
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12
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Santoro M, Coi A, Barišić I, Pierini A, Addor MC, Baldacci S, Ballardini E, Boban L, Braz P, Cavero-Carbonell C, de Walle HEK, Draper ES, Gatt M, Haeusler M, Klungsøyr K, Kurinczuk JJ, Materna-Kiryluk A, Lanzoni M, Lelong N, Luyt K, Mokoroa O, Mullaney C, Nelen V, O'Mahony MT, Perthus I, Randrianaivo H, Rankin J, Rissmann A, Rouget F, Schaub B, Tucker D, Wellesley D, Zymak-Zakutnia N, Garne E. Epidemiology of Pierre-Robin sequence in Europe: A population-based EUROCAT study. Paediatr Perinat Epidemiol 2021; 35:530-539. [PMID: 34132407 DOI: 10.1111/ppe.12776] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 04/22/2021] [Accepted: 04/25/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND Pierre Robin sequence (PRS) is a rare congenital anomaly. Respiratory disorders and feeding difficulties represent the main burden. OBJECTIVE The aim of this study was to investigate the epidemiology of PRS using a cohort of cases from EUROCAT, the European network of population-based registries of congenital anomalies. METHODS We analysed cases of PRS born in the period 1998-2017 collected by 29 population-based congenital anomaly registries in 17 different countries. We calculated prevalence estimates, prenatal detection rate, survival up to 1 week, and proportions of associated anomalies. The effect of maternal age was tested using a Poisson regression model. RESULTS Out of 11 669 155 surveyed births, a total of 1294 cases of PRS were identified. The estimate of the overall prevalence was 12.0 per 100 000 births (95% CI 9.9, 14.5). There was a total of 882 (68.2%) isolated cases, and the prevalence was 7.8 per 100 000 births (95% CI 6.7, 9.2). A total of 250 cases (19.3%) were associated with other structural congenital anomalies, 77 cases (6.0%) were associated with chromosomal anomalies and 77 (6.0%) with genetic syndromes. The prenatal detection rate in isolated cases was 12.0% (95% CI 9.8, 14.5) and increased to 16.0% (95% CI 12.7, 19.7) in the sub-period 2008-2017. The prevalence rate ratio of non-chromosomal cases with maternal age ≥35 was higher than in cases with maternal age <25 for total (PRR 1.26, 95% CI 1.05, 1.51) and isolated cases (PRR 1.33, 95% CI 1.00, 1.64). Survival of chromosomal cases (94.2%) and multiple anomaly cases (95.3%) were lower than survival of isolated cases (99.4%). CONCLUSIONS This epidemiological study using a large series of cases of PRS provides insights into the epidemiological profile of PRS in Europe. We observed an association with higher maternal age, but further investigations are needed to test potential risk factors for PRS.
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Affiliation(s)
- Michele Santoro
- Unit of Epidemiology of Rare diseases and Congenital anomalies, Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Alessio Coi
- Unit of Epidemiology of Rare diseases and Congenital anomalies, Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Ingeborg Barišić
- Children's Hospital Zagreb, Centre of Excellence for Reproductive and Regenerative Medicine, Medical School University of Zagreb, Zagreb, Croatia
| | - Anna Pierini
- Unit of Epidemiology of Rare diseases and Congenital anomalies, Institute of Clinical Physiology, National Research Council, Pisa, Italy.,Fondazione Toscana Gabriele Monasterio, Pisa, Italy
| | - Marie-Claude Addor
- Department of Woman-Mother-Child University Medical Center CHUV Lausanne, Switzerland
| | - Silvia Baldacci
- Unit of Epidemiology of Rare diseases and Congenital anomalies, Institute of Clinical Physiology, National Research Council, Pisa, Italy
| | - Elisa Ballardini
- Neonatal Intensive Care Unit, Paediatric Section, IMER Registry (Emilia Romagna Registry of Birth Defects), Dep. of Medical Sciences, University of Ferrara, Ferrara, Italy
| | - Ljubica Boban
- Children's Hospital Zagreb, Centre of Excellence for Reproductive and Regenerative Medicine, Medical School University of Zagreb, Zagreb, Croatia
| | - Paula Braz
- Epidemiology Department, National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
| | - Clara Cavero-Carbonell
- Rare Diseases Research Unit, Foundation for the Promotion of Health and Biomedical Research in the Valencian Region, Valencia, Spain
| | - Hermien E K de Walle
- University Medical Center Groningen, Department of Genetics, University of Groningen, Groningen, the Netherlands
| | - Elizabeth S Draper
- Department Health Sciences, College of Life Sciences, University of Leicester, Leicester, UK
| | - Miriam Gatt
- Malta Congenital Anomalies Registry, Directorate for Health Information and Research, G'Mangia, Malta
| | | | - Kari Klungsøyr
- Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway.,Division of Mental and Physical Health, Norwegian Institute of Public Health, Bergen, Norway
| | - Jennifer J Kurinczuk
- National Perinatal Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
| | - Anna Materna-Kiryluk
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
| | - Monica Lanzoni
- European Commission, Joint Research Centre (JRC), Ispra, Italy
| | - Nathalie Lelong
- Epidemiology and Statistics Research Center - CRESS, INSERM, Obstetrical, Perinatal and Pediatric Epidemiology Research Team (EPOPé), Université de Paris, Paris, France
| | - Karen Luyt
- South West Congenital Anomaly Register, Bristol Medical School, University of Bristol, Bristol, UK
| | - Olatz Mokoroa
- Public Health Division of Gipuzkoa, Biodonostia Research Institute, Donostia-San Sebastian, Spain
| | - Carmel Mullaney
- Department of Public Health, HSE South East, Lacken, Kilkenny, Ireland
| | - Vera Nelen
- Provincial Institute of Hygiene, Antwerp, Belgium
| | - Mary T O'Mahony
- Department of Public Health, HSE South (Cork & Kerry), Ireland
| | - Isabelle Perthus
- Auvergne registry of congenital anomalies (CEMC-Auvergne), Department of clinical genetics, Centre de Référence des Maladies Rares, University Hospital of Clermont-Ferrand, Clermont-Ferrand, France
| | - Hanitra Randrianaivo
- Register of Congenital Malformations Isle of Reunion Island, CHU St Pierre, la Reunion, France
| | - Judith Rankin
- Population Health Sciences Institute, Newcastle University/National Congenital Anomaly and Rare Disease Registration Service (NCARDRS), Public Health England, Newcastle upon Tyne, UK
| | - Anke Rissmann
- Malformation Monitoring Centre Saxony-Anhalt, Medical Faculty Otto-von-Guericke University, Magdeburg, Germany
| | - Florence Rouget
- Brittany Registry of Congenital Malformations, CHU Rennes, Univ Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, Environnement et Travail) - UMR_S 1085, Rennes, France
| | - Bruno Schaub
- French West Indies Registry, Registre des Malformations des Antilles (REMALAN), Maison de la Femme de la Mère et de l'Enfant, University Hospital of Martinique, Fort-de-France, France
| | - David Tucker
- Congenital Anomaly Register & Information Service for Wales (CARIS), Public Health Wales, Swansea, UK
| | - Diana Wellesley
- Wessex Clinical Genetics Service, University Hospitals Southampton, Southampton, UK
| | | | - Ester Garne
- Paediatric Department, Hospital Lillebaelt, Kolding, Denmark
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13
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Leypold NA, Speicher MR. Evolutionary conservation in noncoding genomic regions. Trends Genet 2021; 37:903-918. [PMID: 34238591 DOI: 10.1016/j.tig.2021.06.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 05/25/2021] [Accepted: 06/07/2021] [Indexed: 12/28/2022]
Abstract
Humans may share more genomic commonalities with other species than previously thought. According to current estimates, ~5% of the human genome is functionally constrained, which is a much larger fraction than the ~1.5% occupied by annotated protein-coding genes. Hence, ~3.5% of the human genome comprises likely functional conserved noncoding elements (CNEs) preserved among organisms, whose common ancestors existed throughout hundreds of millions of years of evolution. As whole-genome sequencing emerges as a standard procedure in genetic analyses, interpretation of variations in CNEs, including the elucidation of mechanistic and functional roles, becomes a necessity. Here, we discuss the phenomenon of noncoding conservation via four dimensions (sequence, regulatory conservation, spatiotemporal expression, and structure) and the potential significance of CNEs in phenotype variation and disease.
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Affiliation(s)
- Nicole A Leypold
- Institute of Human Genetics, Diagnostic and Research Center for Molecular Biomedicine, Medical University of Graz, 8010 Graz, Austria.
| | - Michael R Speicher
- Institute of Human Genetics, Diagnostic and Research Center for Molecular Biomedicine, Medical University of Graz, 8010 Graz, Austria; BioTechMed-Graz, Graz, Austria.
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14
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Simna SP, Han Z. Prospects Of Non-Coding Elements In Genomic Dna Based Gene Therapy. Curr Gene Ther 2021; 22:89-103. [PMID: 33874871 DOI: 10.2174/1566523221666210419090357] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 11/22/2022]
Abstract
Gene therapy has made significant development since the commencement of the first clinical trials a few decades ago and has remained a dynamic area of research regardless of obstacles such as immune response and insertional mutagenesis. Progression in various technologies like next-generation sequencing (NGS) and nanotechnology has established the importance of non-coding segments of a genome, thereby taking gene therapy to the next level. In this review, we have summarized the importance of non-coding elements, highlighting the advantages of using full-length genomic DNA loci (gDNA) compared to complementary DNA (cDNA) or minigene, currently used in gene therapy. The focus of this review is to provide an overview of the advances and the future of potential use of gDNA loci in gene therapy, expanding the therapeutic repertoire in molecular medicine.
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Affiliation(s)
- S P Simna
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC 27599. United States
| | - Zongchao Han
- Department of Ophthalmology, the University of North Carolina at Chapel Hill, Chapel Hill, NC 27599. United States
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15
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Agrawal P, Rao S. Super-Enhancers and CTCF in Early Embryonic Cell Fate Decisions. Front Cell Dev Biol 2021; 9:653669. [PMID: 33842482 PMCID: PMC8027350 DOI: 10.3389/fcell.2021.653669] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Accepted: 02/18/2021] [Indexed: 12/04/2022] Open
Abstract
Cell fate decisions are the backbone of many developmental and disease processes. In early mammalian development, precise gene expression changes underly the rapid division of a single cell that leads to the embryo and are critically dependent on autonomous cell changes in gene expression. To understand how these lineage specifications events are mediated, scientists have had to look past protein coding genes to the cis regulatory elements (CREs), including enhancers and insulators, that modulate gene expression. One class of enhancers, termed super-enhancers, is highly active and cell-type specific, implying their critical role in modulating cell-type specific gene expression. Deletion or mutations within these CREs adversely affect gene expression and development and can cause disease. In this mini-review we discuss recent studies describing the potential roles of two CREs, enhancers and binding sites for CTCF, in early mammalian development.
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Affiliation(s)
- Puja Agrawal
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI, United States
- Versiti Blood Research Institute, Milwaukee, WI, United States
| | - Sridhar Rao
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI, United States
- Versiti Blood Research Institute, Milwaukee, WI, United States
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, WI, United States
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16
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Wymeersch FJ, Wilson V, Tsakiridis A. Understanding axial progenitor biology in vivo and in vitro. Development 2021; 148:148/4/dev180612. [PMID: 33593754 DOI: 10.1242/dev.180612] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The generation of the components that make up the embryonic body axis, such as the spinal cord and vertebral column, takes place in an anterior-to-posterior (head-to-tail) direction. This process is driven by the coordinated production of various cell types from a pool of posteriorly-located axial progenitors. Here, we review the key features of this process and the biology of axial progenitors, including neuromesodermal progenitors, the common precursors of the spinal cord and trunk musculature. We discuss recent developments in the in vitro production of axial progenitors and their potential implications in disease modelling and regenerative medicine.
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Affiliation(s)
- Filip J Wymeersch
- Laboratory for Human Organogenesis, RIKEN Center for Biosystems Dynamics Research, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan
| | - Valerie Wilson
- Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Anestis Tsakiridis
- Centre for Stem Cell Biology, Department of Biomedical Science, The University of Sheffield, Western Bank, Sheffield S10 2TN UK .,Neuroscience Institute, The University of Sheffield, Western Bank, Sheffield, S10 2TN UK
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17
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Motch Perrine SM, Wu M, Holmes G, Bjork BC, Jabs EW, Richtsmeier JT. Phenotypes, Developmental Basis, and Genetics of Pierre Robin Complex. J Dev Biol 2020; 8:E30. [PMID: 33291480 PMCID: PMC7768358 DOI: 10.3390/jdb8040030] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 11/20/2020] [Accepted: 11/30/2020] [Indexed: 02/08/2023] Open
Abstract
The phenotype currently accepted as Pierre Robin syndrome/sequence/anomalad/complex (PR) is characterized by mandibular dysmorphology, glossoptosis, respiratory obstruction, and in some cases, cleft palate. A causative sequence of developmental events is hypothesized for PR, but few clear causal relationships between discovered genetic variants, dysregulated gene expression, precise cellular processes, pathogenesis, and PR-associated anomalies are documented. This review presents the current understanding of PR phenotypes, the proposed pathogenetic processes underlying them, select genes associated with PR, and available animal models that could be used to better understand the genetic basis and phenotypic variation of PR.
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Affiliation(s)
- Susan M. Motch Perrine
- Department of Anthropology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Meng Wu
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (M.W.); (G.H.); (E.W.J.)
| | - Greg Holmes
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (M.W.); (G.H.); (E.W.J.)
| | - Bryan C. Bjork
- Department of Biochemistry and Molecular Genetics, Chicago College of Osteopathic Medicine, Midwestern University, Downers Grove, IL 60515, USA;
| | - Ethylin Wang Jabs
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; (M.W.); (G.H.); (E.W.J.)
| | - Joan T. Richtsmeier
- Department of Anthropology, The Pennsylvania State University, University Park, PA 16802, USA
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18
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Long HK, Osterwalder M, Welsh IC, Hansen K, Davies JOJ, Liu YE, Koska M, Adams AT, Aho R, Arora N, Ikeda K, Williams RM, Sauka-Spengler T, Porteus MH, Mohun T, Dickel DE, Swigut T, Hughes JR, Higgs DR, Visel A, Selleri L, Wysocka J. Loss of Extreme Long-Range Enhancers in Human Neural Crest Drives a Craniofacial Disorder. Cell Stem Cell 2020; 27:765-783.e14. [PMID: 32991838 PMCID: PMC7655526 DOI: 10.1016/j.stem.2020.09.001] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 06/09/2020] [Accepted: 09/02/2020] [Indexed: 01/09/2023]
Abstract
Non-coding mutations at the far end of a large gene desert surrounding the SOX9 gene result in a human craniofacial disorder called Pierre Robin sequence (PRS). Leveraging a human stem cell differentiation model, we identify two clusters of enhancers within the PRS-associated region that regulate SOX9 expression during a restricted window of facial progenitor development at distances up to 1.45 Mb. Enhancers within the 1.45 Mb cluster exhibit highly synergistic activity that is dependent on the Coordinator motif. Using mouse models, we demonstrate that PRS phenotypic specificity arises from the convergence of two mechanisms: confinement of Sox9 dosage perturbation to developing facial structures through context-specific enhancer activity and heightened sensitivity of the lower jaw to Sox9 expression reduction. Overall, we characterize the longest-range human enhancers involved in congenital malformations, directly demonstrate that PRS is an enhanceropathy, and illustrate how small changes in gene expression can lead to morphological variation.
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Affiliation(s)
- Hannah K Long
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Marco Osterwalder
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Ian C Welsh
- Program in Craniofacial Biology, Department of Orofacial Sciences and Department of Anatomy, Institute of Human Genetics, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
| | - Karissa Hansen
- Program in Craniofacial Biology, Department of Orofacial Sciences and Department of Anatomy, Institute of Human Genetics, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
| | - James O J Davies
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Yiran E Liu
- Cancer Biology Program, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Mervenaz Koska
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Alexander T Adams
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Robert Aho
- Program in Craniofacial Biology, Department of Orofacial Sciences and Department of Anatomy, Institute of Human Genetics, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
| | - Neha Arora
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Kazuya Ikeda
- Department of Pediatrics, Stanford University, Stanford, CA 94305, USA
| | - Ruth M Williams
- MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Tatjana Sauka-Spengler
- MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Matthew H Porteus
- Department of Pediatrics, Stanford University, Stanford, CA 94305, USA
| | - Tim Mohun
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, Mill Hill, London NW7 1AA, UK
| | - Diane E Dickel
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Tomek Swigut
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Jim R Hughes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Douglas R Higgs
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK; Laboratory of Gene Regulation, MRC Weatherall Institute of Molecular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Axel Visel
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; US Department of Energy Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; School of Natural Sciences, University of California, Merced, Merced, CA 95343, USA
| | - Licia Selleri
- Program in Craniofacial Biology, Department of Orofacial Sciences and Department of Anatomy, Institute of Human Genetics, Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco, San Francisco, CA, USA
| | - Joanna Wysocka
- Department of Chemical and Systems Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA 94305, USA; Institute of Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA 94305, USA.
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19
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Interpreting the impact of noncoding structural variation in neurodevelopmental disorders. Genet Med 2020; 23:34-46. [PMID: 32973355 PMCID: PMC7790743 DOI: 10.1038/s41436-020-00974-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 09/03/2020] [Accepted: 09/14/2020] [Indexed: 12/21/2022] Open
Abstract
The emergence of novel sequencing technologies has greatly improved the identification of structural variation, revealing that a human genome harbors tens of thousands of structural variants (SVs). Since these SVs primarily impact noncoding DNA sequences, the next challenge is one of interpretation, not least to improve our understanding of human disease etiology. However, this task is severely complicated by the intricacy of the gene regulatory landscapes embedded within these noncoding regions, their incomplete annotation, as well as their dependence on the three-dimensional (3D) conformation of the genome. Also in the context of neurodevelopmental disorders (NDDs), reports of putatively causal, noncoding SVs are accumulating and understanding their impact on transcriptional regulation is presenting itself as the next step toward improved genetic diagnosis.
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20
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van der Lee R, Correard S, Wasserman WW. Deregulated Regulators: Disease-Causing cis Variants in Transcription Factor Genes. Trends Genet 2020; 36:523-539. [DOI: 10.1016/j.tig.2020.04.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Revised: 04/15/2020] [Accepted: 04/16/2020] [Indexed: 12/12/2022]
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21
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Liu S, Narumi R, Ikeda N, Morita O, Tasaki J. Chemical-induced craniofacial anomalies caused by disruption of neural crest cell development in a zebrafish model. Dev Dyn 2020; 249:794-815. [PMID: 32314458 PMCID: PMC7384000 DOI: 10.1002/dvdy.179] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 04/12/2020] [Accepted: 04/13/2020] [Indexed: 12/11/2022] Open
Abstract
Background Craniofacial anomalies are among the most frequent birth defects worldwide, and are thought to be caused by gene‐environment interactions. Genetically manipulated zebrafish simulate human diseases and provide great advantages for investigating the etiology and pathology of craniofacial anomalies. Although substantial advances have been made in understanding genetic factors causing craniofacial disorders, limited information about the etiology by which environmental factors, such as teratogens, induce craniofacial anomalies is available in zebrafish. Results Zebrafish embryos displayed craniofacial malformations after teratogen treatments. Further observations revealed characteristic disruption of chondrocyte number, shape and stacking. These findings suggested aberrant development of cranial neural crest (CNC) cells, which was confirmed by gene expression analysis of the CNC. Notably, these observations suggested conserved etiological pathways between zebrafish and mammals including human. Furthermore, several of these chemicals caused malformations of the eyes, otic vesicle, and/or heart, representing a phenocopy of neurocristopathy, and these chemicals altered the expression levels of the responsible genes. Conclusions Our results demonstrate that chemical‐induced craniofacial malformation is caused by aberrant development of neural crest. This study indicates that zebrafish provide a platform for investigating contributions of environmental factors as causative agents of craniofacial anomalies and neurocristopathy.
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Affiliation(s)
- Shujie Liu
- R&D, Safety Science Research, Kao Corporation, Tochigi, Japan
| | - Rika Narumi
- R&D, Safety Science Research, Kao Corporation, Tochigi, Japan
| | - Naohiro Ikeda
- R&D, Safety Science Research, Kao Corporation, Tochigi, Japan
| | - Osamu Morita
- R&D, Safety Science Research, Kao Corporation, Tochigi, Japan
| | - Junichi Tasaki
- R&D, Safety Science Research, Kao Corporation, Tochigi, Japan
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22
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Wilderman A, VanOudenhove J, Kron J, Noonan JP, Cotney J. High-Resolution Epigenomic Atlas of Human Embryonic Craniofacial Development. Cell Rep 2019; 23:1581-1597. [PMID: 29719267 PMCID: PMC5965702 DOI: 10.1016/j.celrep.2018.03.129] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Revised: 12/05/2017] [Accepted: 03/28/2018] [Indexed: 11/29/2022] Open
Abstract
Defects in patterning during human embryonic development frequently result in craniofacial abnormalities. The gene regulatory programs that build the craniofacial complex are likely controlled by information located between genes and within intronic sequences. However, systematic identification of regulatory sequences important for forming the human face has not been performed. Here, we describe comprehensive epigenomic annotations from human embryonic craniofacial tissues and systematic comparisons with multiple tissues and cell types. We identified thousands of tissue-specific craniofacial regulatory sequences and likely causal regions for rare craniofacial abnormalities. We demonstrate significant enrichment of common variants associated with orofacial clefting in enhancers active early in embryonic development, while those associated with normal facial variation are enriched near the end of the embryonic period. These data are provided in easily accessible formats for both craniofacial researchers and clinicians to aid future experimental design and interpretation of noncoding variation in those affected by craniofacial abnormalities.
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Affiliation(s)
- Andrea Wilderman
- Graduate Program in Genetics and Developmental Biology, UConn Health, Farmington, CT 06030, USA; Department of Genetics and Genome Sciences, UConn Health, Farmington, CT 06030, USA
| | | | - Jeffrey Kron
- Department of Genetics and Genome Sciences, UConn Health, Farmington, CT 06030, USA
| | - James P Noonan
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06510, USA; Kavli Institute for Neuroscience, Yale University, New Haven, CT 06520, USA
| | - Justin Cotney
- Department of Genetics and Genome Sciences, UConn Health, Farmington, CT 06030, USA; Institute for Systems Genomics, University of Connecticut, Storrs, CT 06269, USA.
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23
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Ho EYK, Cao Q, Gu M, Chan RWL, Wu Q, Gerstein M, Yip KY. Shaping the nebulous enhancer in the era of high-throughput assays and genome editing. Brief Bioinform 2019; 21:836-850. [PMID: 30895290 DOI: 10.1093/bib/bbz030] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Revised: 02/15/2019] [Accepted: 02/26/2019] [Indexed: 01/22/2023] Open
Abstract
Since the 1st discovery of transcriptional enhancers in 1981, their textbook definition has remained largely unchanged in the past 37 years. With the emergence of high-throughput assays and genome editing, which are switching the paradigm from bottom-up discovery and testing of individual enhancers to top-down profiling of enhancer activities genome-wide, it has become increasingly evidenced that this classical definition has left substantial gray areas in different aspects. Here we survey a representative set of recent research articles and report the definitions of enhancers they have adopted. The results reveal that a wide spectrum of definitions is used usually without the definition stated explicitly, which could lead to difficulties in data interpretation and downstream analyses. Based on these findings, we discuss the practical implications and suggestions for future studies.
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Affiliation(s)
| | - Qin Cao
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong
| | - Mengting Gu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
| | - Ricky Wai-Lun Chan
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong
| | - Qiong Wu
- Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong.,School of Biomedical Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Mark Gerstein
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA.,Program in Computational Biology and Bioinformatics.,Department of Computer Science, Yale University, New Haven, Connecticut, USA
| | - Kevin Y Yip
- Department of Biomedical Engineering.,Department of Computer Science and Engineering, The Chinese University of Hong Kong, Hong Kong.,Hong Kong Bioinformatics Centre.,CUHK-BGI Innovation Institute of Trans-omics.,Hong Kong Institute of Diabetes and Obesity, The Chinese University of Hong Kong, Hong Kong
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Manocha S, Farokhnia N, Khosropanah S, Bertol JW, Santiago J, Fakhouri WD. Systematic review of hormonal and genetic factors involved in the nonsyndromic disorders of the lower jaw. Dev Dyn 2019; 248:162-172. [PMID: 30576023 DOI: 10.1002/dvdy.8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Revised: 11/30/2018] [Accepted: 12/14/2018] [Indexed: 12/14/2022] Open
Abstract
Mandibular disorders are among the most common birth defects in humans, yet the etiological factors are largely unknown. Most of the neonates affected by mandibular abnormalities have a sequence of secondary anomalies, including airway obstruction and feeding problems, that reduce the quality of life. In the event of lacking corrective surgeries, patients with mandibular congenital disorders suffer from additional lifelong problems such as sleep apnea and temporomandibular disorders, among others. The goal of this systematic review is to gather evidence on hormonal and genetic factors that are involved in signaling pathways and interactions that are potentially associated with the nonsyndromic mandibular disorders. We found that members of FGF and BMP pathways, including FGF8/10, FGFR2/3, BMP2/4/7, BMPR1A, ACVR1, and ACVR2A/B, have a prominent number of gene-gene interactions among all identified genes in this review. Gene ontology of the 154 genes showed that the functional gene sets are involved in all aspects of cellular processes and organogenesis. Some of the genes identified by the genome-wide association studies of common mandibular disorders are involved in skeletal formation and growth retardation based on animal models, suggesting a potential direct role as genetic risk factors in the common complex jaw disorders. Developmental Dynamics 248:162-172, 2019. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Srishti Manocha
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas
| | - Nadia Farokhnia
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas
| | - Sepideh Khosropanah
- Ostrow School of Dentistry, University of Southern California, California, Los Angeles
| | - Jessica W Bertol
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas
| | - Joel Santiago
- Pró-Reitoria de Pesquisa e Pós-graduação (PRPPG), Universidade do Sagrado Coração, Jardim Brasil, Bauru, Sao Paulo, Brazil
| | - Walid D Fakhouri
- Center for Craniofacial Research, Department of Diagnostic and Biomedical Sciences, School of Dentistry, University of Texas Health Science Center at Houston, Houston, Texas.,Department of Pediatrics, McGovern Medical School, University of Texas Health Science Center, Houston, Texas
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25
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Yip RK, Chan D, Cheah KS. Mechanistic insights into skeletal development gained from genetic disorders. Curr Top Dev Biol 2019; 133:343-385. [DOI: 10.1016/bs.ctdb.2019.02.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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26
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Pierre Robin sequence: A comprehensive narrative review of the literature over time. JOURNAL OF STOMATOLOGY, ORAL AND MAXILLOFACIAL SURGERY 2018; 119:419-428. [DOI: 10.1016/j.jormas.2018.05.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 05/11/2018] [Indexed: 12/12/2022]
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de Blacam C, Duggan L, Rea D, Beddy P, Orr DJA. Descent of the human larynx: An unrecognized factor in airway distress in babies with cleft palate? Int J Pediatr Otorhinolaryngol 2018; 113:208-212. [PMID: 30173987 DOI: 10.1016/j.ijporl.2018.07.052] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Revised: 07/28/2018] [Accepted: 07/29/2018] [Indexed: 11/15/2022]
Abstract
The intranarial epiglottis, a feature of all newborn mammals, allows suckling and breathing to continue almost simultaneously by separating an oral food stream from a nasal airstream. In contrast to other mammals, the human larynx descends in the neck between birth and six months, extending the distance between the caudal aspect of the soft palate and the cephalic tip of the epiglottis. The mechanism of airway protection changes from a pattern in which an upright epiglottis is grasped by an intact palatopharyngeal sphincter to one in which the epiglottis folds down over the laryngeal aditus and the adducted vocal folds. The comparative anatomy and anthropological literature describing laryngeal descent was reviewed. A series of MRI images were used to illustrate the normal descent of the human larynx, which take place in infants in the first six months of life. Based on this information, we hypothesize that a cleft palate, by interrupting the sphincter function of palatopharyngeus on a high neonatal epiglottis, precipitates a need for premature and rapid maturation of the neonate's airway protection pattern, particularly during feeding. This may explain why, even in the absence of Robin sequence, some babies with cleft palates suffer respiratory distress during feeding.
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Affiliation(s)
- Catherine de Blacam
- Dublin Cleft Centre, Our Lady's Children's Hospital Crumlin, Dublin, Ireland.
| | - Laura Duggan
- Dublin Cleft Centre, Our Lady's Children's Hospital Crumlin, Dublin, Ireland
| | - David Rea
- Department of Radiology, Our Lady's Children's Hospital Crumlin, Dublin, Ireland
| | - Peter Beddy
- Department of Radiology, St James's Hospital, Dublin, Ireland
| | - David J A Orr
- Dublin Cleft Centre, Our Lady's Children's Hospital Crumlin, Dublin, Ireland; Department of Surgery and Paediatrics, Trinity College Dublin, Ireland
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28
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Cha S, Lim JE, Park AY, Do JH, Lee SW, Shin C, Cho NH, Kang JO, Nam JM, Kim JS, Woo KM, Lee SH, Kim JY, Oh B. Identification of five novel genetic loci related to facial morphology by genome-wide association studies. BMC Genomics 2018; 19:481. [PMID: 29921221 PMCID: PMC6008943 DOI: 10.1186/s12864-018-4865-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 06/12/2018] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Face morphology is strongly determined by genetic factors. However, only a small number of genes related to face morphology have been identified to date. Here, we performed a two-stage genome-wide association study (GWAS) of 85 face morphological traits in 7569 Koreans (5643 in the discovery set and 1926 in the replication set). RESULTS In this study, we analyzed 85 facial traits, including facial angles. After discovery GWAS, 128 single nucleotide polymorphisms (SNPs) showing an association of P < 5 × 10- 6 were selected to determine the replication of the associations, and meta-analysis of discovery GWAS and the replication analysis resulted in five genome-wide significant loci. The OSR1-WDR35 [rs7567283, G allele, beta (se) = -0.536 (0.096), P = 2.75 × 10- 8] locus was associated with the facial frontal contour; the HOXD1-MTX2 [rs970797, A allele, beta (se) = 0.015 (0.003), P = 3.97 × 10- 9] and WDR27 [rs3736712, C allele, beta (se) = 0.293 (0.048), P = 8.44 × 10- 10] loci were associated with eye shape; and the SOX9 [rs2193054, C allele, beta (se) (ln-transformed) = -0.007 (0.001), P = 6.17 × 10- 17] and DHX35 [rs2206437, A allele, beta (se) = -0.283 (0.047), P = 1.61 × 10- 9] loci were associated with nose shape. WDR35 and SOX9 were related to known craniofacial malformations, i.e., cranioectodermal dysplasia 2 and campomelic dysplasia, respectively. In addition, we found three independent association signals in the SOX9 locus, and six known loci for nose size and shape were replicated in this study population. Interestingly, four SNPs within these five face morphology-related loci showed discrepancies in allele frequencies among ethnic groups. CONCLUSIONS We identified five novel face morphology loci that were associated with facial frontal contour, nose shape, and eye shape. Our findings provide useful genetic information for the determination of face morphology.
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Affiliation(s)
- Seongwon Cha
- Future Medicine Division, Korea Institute of Oriental Medicine, Daejeon, 34054, Republic of Korea
| | - Ji Eun Lim
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Ah Yeon Park
- Mibyeong Research Center, Korea Institute of Oriental Medicine, Daejeon, 34054, Republic of Korea
| | - Jun-Hyeong Do
- Future Medicine Division, Korea Institute of Oriental Medicine, Daejeon, 34054, Republic of Korea
| | - Si Woo Lee
- Future Medicine Division, Korea Institute of Oriental Medicine, Daejeon, 34054, Republic of Korea
| | - Chol Shin
- Division of Pulmonary Sleep and Critical Care Medicine, Department of Internal Medicine, Korea University Ansan Hospital and Institute of Human Genomic Study, Korea University Ansan Hospital, Ansan, 15355, Republic of Korea
| | - Nam Han Cho
- Department of Preventive Medicine, Ajou University School of Medicine, Suwon, 16499, Republic of Korea
| | - Ji-One Kang
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Jeong Min Nam
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea
| | - Jong-Sik Kim
- DNA Forensic Division, Supreme Prosecutors' Office, Seoul, 06590, Republic of Korea
| | - Kwang-Man Woo
- DNA Forensic Division, Supreme Prosecutors' Office, Seoul, 06590, Republic of Korea
| | - Seung-Hwan Lee
- DNA Forensic Division, Supreme Prosecutors' Office, Seoul, 06590, Republic of Korea
| | - Jong Yeol Kim
- KM Fundamental Research Division, Korea Institute of Oriental Medicine, Daejeon, 34054, Republic of Korea
| | - Bermseok Oh
- Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, 02447, Republic of Korea.
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29
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Logjes RJH, Breugem CC, Van Haaften G, Paes EC, Sperber GH, van den Boogaard MJH, Farlie PG. The ontogeny of Robin sequence. Am J Med Genet A 2018; 176:1349-1368. [PMID: 29696787 DOI: 10.1002/ajmg.a.38718] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Revised: 12/17/2017] [Accepted: 03/23/2018] [Indexed: 02/06/2023]
Abstract
The triad of micrognathia, glossoptosis, and concomitant airway obstruction defined as "Robin sequence" (RS) is caused by oropharyngeal developmental events constrained by a reduced stomadeal space. This sequence of abnormal embryonic development also results in an anatomical configuration that might predispose the fetus to a cleft palate. RS is heterogeneous and many different etiologies have been described including syndromic, RS-plus, and isolated forms. For an optimal diagnosis, subsequent treatment and prognosis, a thorough understanding of the embryology and pathogenesis is necessary. This manuscript provides an update about our current understanding of the development of the mandible, tongue, and palate and possible mechanisms involved in the development of RS. Additionally, we provide the reader with an up-to-date summary of the different etiologies of this phenotype and link this to the embryologic, developmental, and genetic mechanisms.
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Affiliation(s)
- Robrecht J H Logjes
- Department of Plastic and Reconstructive Surgery, University Medical Center Utrecht, Wilhelmina Children's Hospital Utrecht, Utrecht, The Netherlands
| | - Corstiaan C Breugem
- Department of Plastic and Reconstructive Surgery, University Medical Center Utrecht, Wilhelmina Children's Hospital Utrecht, Utrecht, The Netherlands
| | - Gijs Van Haaften
- Department of Genetics, Center for Molecular Medicine, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Emma C Paes
- Department of Plastic and Reconstructive Surgery, University Medical Center Utrecht, Wilhelmina Children's Hospital Utrecht, Utrecht, The Netherlands
| | - Geoffrey H Sperber
- Faculty of Medicine and Dentistry, University of Alberta, Alberta, Canada
| | | | - Peter G Farlie
- Royal Children's Hospital, Murdoch Children's Research Institute, Parkville, Australia
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30
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Enhancer redundancy provides phenotypic robustness in mammalian development. Nature 2018; 554:239-243. [PMID: 29420474 PMCID: PMC5808607 DOI: 10.1038/nature25461] [Citation(s) in RCA: 389] [Impact Index Per Article: 64.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Accepted: 12/18/2017] [Indexed: 12/30/2022]
Abstract
Distant-acting tissue-specific enhancers vastly outnumber protein-coding genes in mammalian genomes, but the functional significance of this regulatory complexity remains insufficiently understood1,2. Here we show that the pervasive presence of multiple enhancers with similar activities near the same gene confers phenotypic robustness to loss-of-function mutations in individual enhancers. We used genome editing to create 23 mouse deletion lines and inter-crosses, including both single and combinatorial enhancer deletions at seven distinct loci required for limb development. Surprisingly, none of ten deletions of individual enhancers caused noticeable changes in limb morphology. In contrast, removal of pairs of limb enhancers near the same gene resulted in discernible phenotypes, indicating that enhancers function redundantly in establishing normal morphology. In a genetic background sensitized by reduced baseline expression of the target gene, even single enhancer deletions caused limb abnormalities, suggesting that functional redundancy is conferred by additive effects of enhancers on gene expression levels. A genome-wide analysis integrating epigenomic and transcriptomic data from 29 developmental mouse tissues revealed that mammalian genes are very commonly associated with multiple enhancers that have similar spatiotemporal activity. Systematic exploration of three representative developmental structures (limb, brain, heart) uncovered more than a thousand cases in which five or more enhancers with redundant activity patterns were found near the same gene. Taken together, our data indicate that enhancer redundancy is a remarkably widespread feature of mammalian genomes and provides an effective regulatory buffer preventing deleterious phenotypic consequences upon loss of individual enhancers.
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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.
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32
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Morozumi K, Ainoya K, Takemoto J, Sakai K. Newly Identified t(2;17)(p15;q24.2) Chromosomal Translocation Is Associated with Dysgenetic Gonads and Multiple Somatic Anomalies. TOHOKU J EXP MED 2018; 245:187-191. [DOI: 10.1620/tjem.245.187] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Kento Morozumi
- Department of Urology, Yamagata Prefectural Central Hospital
| | - Keiko Ainoya
- Department of Urology, Miyagi Children’s Hospital
| | - Jun Takemoto
- Department of Urology, Miyagi Children’s Hospital
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Wang JS, Infante CR, Park S, Menke DB. PITX1 promotes chondrogenesis and myogenesis in mouse hindlimbs through conserved regulatory targets. Dev Biol 2017; 434:186-195. [PMID: 29273440 DOI: 10.1016/j.ydbio.2017.12.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 12/05/2017] [Accepted: 12/18/2017] [Indexed: 10/18/2022]
Abstract
The PITX1 transcription factor is expressed during hindlimb development, where it plays a critical role in directing hindlimb growth and the specification of hindlimb morphology. While it is known that PITX1 regulates hindlimb formation, in part, through activation of the Tbx4 gene, other transcriptional targets remain to be elucidated. We have used a combination of ChIP-seq and RNA-seq to investigate enhancer regions and target genes that are directly regulated by PITX1 in embryonic mouse hindlimbs. In addition, we have analyzed PITX1 binding sites in hindlimbs of Anolis lizards to identify ancient PITX1 regulatory targets. We find that PITX1-bound regions in both mouse and Anolis hindlimbs are strongly associated with genes implicated in limb and skeletal system development. Gene expression analyses reveal a large number of misexpressed genes in the hindlimbs of Pitx1-/- mouse embryos. By intersecting misexpressed genes with genes that have neighboring mouse PITX1 binding sites, we identified 440 candidate targets of PITX1. Of these candidates, 68 exhibit ultra-conserved PITX1 binding events that are shared between mouse and Anolis hindlimbs. Among the ancient targets of PITX1 are important regulators of cartilage and skeletal muscle development, including Sox9 and Six1. Our data suggest that PITX1 promotes chondrogenesis and myogenesis in the hindlimb by direct regulation of several key members of the cartilage and muscle transcriptional networks.
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Affiliation(s)
- Jialiang S Wang
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Carlos R Infante
- Department of Genetics, University of Georgia, Athens, GA 30602, USA; Department of Molecular and Cellular Biology, University of Arizona, Tucson, AZ 85721, USA
| | - Sungdae Park
- Department of Genetics, University of Georgia, Athens, GA 30602, USA
| | - Douglas B Menke
- Department of Genetics, University of Georgia, Athens, GA 30602, USA.
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34
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Di Pasquo E, Amiel J, Roth P, Malan V, Lind K, Chalouhi C, Soupre V, Gordon CT, Lyonnet S, Salomon LJ, Abadie V. Efficiency of prenatal diagnosis in Pierre Robin sequence. Prenat Diagn 2017; 37:1169-1175. [DOI: 10.1002/pd.5162] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 09/13/2017] [Accepted: 09/19/2017] [Indexed: 01/26/2023]
Affiliation(s)
- Elvira Di Pasquo
- Gynecology and Obstetrics Unit, Prenatal Diagnosis Centre; Necker Hospital; Paris France
| | - Jeanne Amiel
- Laboratory of Embryology and Genetics of Congenital Malformations; Institut National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine; Paris France
- Paris Descartes-Sorbonne Paris Cité University; Paris France
| | - Philippe Roth
- Gynecology and Obstetrics Unit, Prenatal Diagnosis Centre; Necker Hospital; Paris France
| | - Valérie Malan
- Cytogenetics Laboratory; Necker Hospital; Paris France
| | - Katia Lind
- General Pediatrics Department and Rare Disease Reference Centre “Syndrome de Pierre Robin et Troubles de Succion Déglutition Congénitaux”; Necker Hospital; Paris France
| | - Christel Chalouhi
- General Pediatrics Department and Rare Disease Reference Centre “Syndrome de Pierre Robin et Troubles de Succion Déglutition Congénitaux”; Necker Hospital; Paris France
| | | | - Christopher T. Gordon
- Laboratory of Embryology and Genetics of Congenital Malformations; Institut National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine; Paris France
- Paris Descartes-Sorbonne Paris Cité University; Paris France
| | - Stanislas Lyonnet
- Laboratory of Embryology and Genetics of Congenital Malformations; Institut National de la Santé et de la Recherche Médicale (INSERM) UMR 1163, Institut Imagine; Paris France
- Paris Descartes-Sorbonne Paris Cité University; Paris France
| | - Laurent J. Salomon
- Gynecology and Obstetrics Unit, Prenatal Diagnosis Centre; Necker Hospital; Paris France
- Paris Descartes-Sorbonne Paris Cité University; Paris France
| | - Véronique Abadie
- Paris Descartes-Sorbonne Paris Cité University; Paris France
- General Pediatrics Department and Rare Disease Reference Centre “Syndrome de Pierre Robin et Troubles de Succion Déglutition Congénitaux”; Necker Hospital; Paris France
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35
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Thieme F, Ludwig K. The Role of Noncoding Genetic Variation in Isolated Orofacial Clefts. J Dent Res 2017; 96:1238-1247. [DOI: 10.1177/0022034517720403] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
In the past decade, medical genetic research has generated multiple discoveries, many of which were obtained via genome-wide association studies (GWASs). A major GWAS finding is that the majority of risk variants for complex traits map to noncoding regions. This has resulted in a paradigm shift in terms of the interpretation of human genomic sequence variation, with more attention now being paid to what was previously termed “junk DNA.” Translation of genetic findings into biologically meaningful results requires 1) large-scale and cell-specific efforts to annotate non-protein–coding regions and 2) the integration of comprehensive genomic data sets. However, this represents an enormous challenge, particularly in the case of human traits that arise during embryonic development, such as orofacial clefts (OFCs). OFC is a multifactorial trait and ranks among the most common of all human congenital malformations. These 2 attributes apply in particular to its isolated forms (nonsyndromic OFC [nsOFC]). Although genetic studies (including GWASs) have yielded novel insights into the genetic architecture of nsOFC, few data are available concerning causality and affected biological pathways. Reasons for this deficiency include the complex genetic architecture at risk loci and the limited availability of functional data sets from human tissues that represent relevant embryonic sites and time points. The present review summarizes current knowledge of the role of noncoding regions in nsOFC etiology. We describe the identification of genetic risk factors for nsOFC and several of the approaches used to identify causal variants at these loci. These strategies include the use of biological and genetic information from public databases, the assessment of the full spectrum of genetic variability within 1 locus, and comprehensive in vitro and in vivo experiments. This review also highlights the role of the emerging research field “functional genomics” and its increasing contribution to our biological understanding of nsOFC.
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Affiliation(s)
- F. Thieme
- Institute of Human Genetics, University of Bonn, Bonn, Germany
- Department of Genomics, Life & Brain Center, University of Bonn, Bonn, Germany
| | - K.U. Ludwig
- Institute of Human Genetics, University of Bonn, Bonn, Germany
- Department of Genomics, Life & Brain Center, University of Bonn, Bonn, Germany
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36
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Matthews DG, Albertson RC. Effect of craniofacial genotype on the relationship between morphology and feeding performance in cichlid fishes. Evolution 2017; 71:2050-2061. [PMID: 28598501 DOI: 10.1111/evo.13289] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 05/12/2017] [Accepted: 05/22/2017] [Indexed: 01/11/2023]
Abstract
The relationship between morphology and performance is complex, but important for understanding the adaptive nature of morphological variation. Recent studies have sought to better understand this system by illuminating the interconnectedness of different functional systems; however, the role of genetics is often overlooked. In this study, we attempt to gain insights into this relationship by examining the effect of genotypic variation at putative craniofacial loci on the relationship between morphology and feeding performance in cichlids. We studied two morphologically disparate species, as well as a morphologically intermediate hybrid population. We assessed feeding performance, jaw protrusion, and general facial morphology for each fish. We also genotyped hybrid animals at six previously identified craniofacial loci. Cichlid species were found to differ in facial geometry, kinematic morphology, and performance. Significant correlations were also noted between these variables; however, the explanatory power of facial geometry in predicting performance was relatively poor. Notably, when hybrids were grouped by genotype, the relationship between shape and performance improved. This relationship was especially robust in animals with the specialist allele at sox9b, a well-characterized regulator of craniofacial development. These data suggest a novel role for genotype in influencing complex relationships between form and function.
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Affiliation(s)
- David G Matthews
- Department of Biology, University of Massachusetts Amherst, Amherst, Massachusetts, 01003
| | - R Craig Albertson
- Department of Biology, University of Massachusetts Amherst, Amherst, Massachusetts, 01003
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37
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Symon A, Harley V. SOX9: A genomic view of tissue specific expression and action. Int J Biochem Cell Biol 2017; 87:18-22. [DOI: 10.1016/j.biocel.2017.03.005] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 03/09/2017] [Accepted: 03/11/2017] [Indexed: 11/29/2022]
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38
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Hojo H, Chung UI, Ohba S. Identification of the gene-regulatory landscape in skeletal development and potential links to skeletal regeneration. Regen Ther 2017; 6:100-107. [PMID: 30271844 PMCID: PMC6134913 DOI: 10.1016/j.reth.2017.04.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 04/03/2017] [Accepted: 04/06/2017] [Indexed: 12/21/2022] Open
Abstract
A class of gene-regulatory elements called enhancers are the main mediators controlling quantitative, temporal and spatial gene expressions. In the course of evolution, the enhancer landscape of higher organisms such as mammals has become quite complex, exerting biological functions precisely and coordinately. In mammalian skeletal development, the master transcription factors Sox9, Runx2 and Sp7/Osterix function primarily through enhancers on the genome to achieve specification and differentiation of skeletal cells. Recently developed genome-scale analyses have shed light on multiple layers of gene regulations, uncovering not only the primary mode of actions of these transcription factors on skeletal enhancers, but also the relation of the epigenetic landscape to three-dimensional chromatin architecture. Here, we review findings on the emerging framework of gene-regulatory networks involved in skeletal development. We further discuss the power of genome-scale analyses to provide new insights into genetic diseases and regenerative medicine in skeletal tissues. Skeletal development is coordinated by master transcription factors. ChIP-seq analyses for the skeletal regulators identified their modes of actions. Analyses of epigenetic landscape features distinct cell types in skeletal tissues. Integrated analyses of the gene regulatory networks link to skeletal regeneration.
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Affiliation(s)
- Hironori Hojo
- Department of Bioengineering, The University of Tokyo Graduate School of Engineering, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Ung-Il Chung
- Department of Bioengineering, The University of Tokyo Graduate School of Engineering, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.,Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
| | - Shinsuke Ohba
- Department of Bioengineering, The University of Tokyo Graduate School of Engineering, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.,Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
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Smyk M, Akdemir KC, Stankiewicz P. SOX9 chromatin folding domains correlate with its real and putative distant cis-regulatory elements. Nucleus 2017; 8:182-187. [PMID: 28085555 DOI: 10.1080/19491034.2017.1279776] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Evolutionary conserved transcription factor SOX9, encoded by the dosage sensitive SOX9 gene on chromosome 17q24.3, plays an important role in development of multiple organs, including bones and testes. Heterozygous point mutations and genomic copy-number variant (CNV) deletions involving SOX9 have been reported in patients with campomelic dysplasia (CD), a skeletal malformation syndrome often associated with male-to-female sex reversal. Balanced and unbalanced structural genomic variants with breakpoints mapping up to 1.3 Mb up- and downstream to SOX9 have been described in patients with milder phenotypes, including acampomelic campomelic dysplasia, sex reversal, and Pierre Robin sequence. Based on the localization of breakpoints of genomic rearrangements causing different phenotypes, 5 genomic intervals mapping upstream to SOX9 have been defined. We have analyzed the publically available database of high-throughput chromosome conformation capture (Hi-C) in multiple cell lines in the genomic regions flanking SOX9. Consistent with the literature data, chromatin domain boundaries in the SOX9 locus exhibit conservation across species and remain largely constant across multiple cell types. Interestingly, we have found that chromatin folding domains in the SOX9 locus associate with the genomic intervals harboring real and putative regulatory elements of SOX9, implicating that variation in intra-domain interactions may be critical for dynamic regulation of SOX9 expression in a cell type-specific fashion. We propose that tissue-specific enhancers for other transcription factor genes may similarly utilize chromatin folding sub-domains in gene regulation.
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Affiliation(s)
- Marta Smyk
- a Department of Medical Genetics , Institute of Mother and Child , Warsaw , Poland
| | - Kadir Caner Akdemir
- b Genomic Medicine Department , MD Anderson Cancer Center , Houston , TX , USA
| | - Paweł Stankiewicz
- c Department of Molecular and Human Genetics , Baylor College of Medicine , Houston , TX , USA
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Abstract
SOX9 is a pivotal transcription factor in developing and adult cartilage. Its gene is expressed from the multipotent skeletal progenitor stage and is active throughout chondrocyte differentiation. While it is repressed in hypertrophic chondrocytes in cartilage growth plates, it remains expressed throughout life in permanent chondrocytes of healthy articular cartilage. SOX9 is required for chondrogenesis: it secures chondrocyte lineage commitment, promotes cell survival, and transcriptionally activates the genes for many cartilage-specific structural components and regulatory factors. Since heterozygous mutations within and around SOX9 were shown to cause the severe skeletal malformation syndrome called campomelic dysplasia, researchers around the world have worked assiduously to decipher the many facets of SOX9 actions and regulation in chondrogenesis. The more we learn, the more we realize the complexity of the molecular networks in which SOX9 fulfills its functions and is regulated at the levels of its gene, RNA, and protein, and the more we measure the many gaps remaining in knowledge. At the same time, new technologies keep giving us more means to push further the frontiers of knowledge. Research efforts must be pursued to fill these gaps and to better understand and treat many types of cartilage diseases in which SOX9 has or could have a critical role. These diseases include chondrodysplasias and cartilage degeneration diseases, namely osteoarthritis, a prevalent and still incurable joint disease. We here review the current state of knowledge of SOX9 actions and regulation in the chondrocyte lineage, and propose new directions for future fundamental and translational research projects.
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Affiliation(s)
- Véronique Lefebvre
- Department of Cellular & Molecular Medicine, Cleveland Clinic Lerner Research Institute, Cleveland, OH
| | - Mona Dvir-Ginzberg
- Institute of Dental Sciences, Faculty of Dental Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
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Ordulu Z, Kammin T, Brand H, Pillalamarri V, Redin CE, Collins RL, Blumenthal I, Hanscom C, Pereira S, Bradley I, Crandall BF, Gerrol P, Hayden MA, Hussain N, Kanengisser-Pines B, Kantarci S, Levy B, Macera MJ, Quintero-Rivera F, Spiegel E, Stevens B, Ulm JE, Warburton D, Wilkins-Haug LE, Yachelevich N, Gusella JF, Talkowski ME, Morton CC. Structural Chromosomal Rearrangements Require Nucleotide-Level Resolution: Lessons from Next-Generation Sequencing in Prenatal Diagnosis. Am J Hum Genet 2016; 99:1015-1033. [PMID: 27745839 PMCID: PMC5097935 DOI: 10.1016/j.ajhg.2016.08.022] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Accepted: 08/26/2016] [Indexed: 12/27/2022] Open
Abstract
In this exciting era of "next-gen cytogenetics," integrating genomic sequencing into the prenatal diagnostic setting is possible within an actionable time frame and can provide precise delineation of balanced chromosomal rearrangements at the nucleotide level. Given the increased risk of congenital abnormalities in newborns with de novo balanced chromosomal rearrangements, comprehensive interpretation of breakpoints could substantially improve prediction of phenotypic outcomes and support perinatal medical care. Herein, we present and evaluate sequencing results of balanced chromosomal rearrangements in ten prenatal subjects with respect to the location of regulatory chromatin domains (topologically associated domains [TADs]). The genomic material from all subjects was interpreted to be "normal" by microarray analyses, and their rearrangements would not have been detected by cell-free DNA (cfDNA) screening. The findings of our systematic approach correlate with phenotypes of both pregnancies with untoward outcomes (5/10) and with healthy newborns (3/10). Two pregnancies, one with a chromosomal aberration predicted to be of unknown clinical significance and another one predicted to be likely benign, were terminated prior to phenotype-genotype correlation (2/10). We demonstrate that the clinical interpretation of structural rearrangements should not be limited to interruption, deletion, or duplication of specific genes and should also incorporate regulatory domains of the human genome with critical ramifications for the control of gene expression. As detailed in this study, our molecular approach to both detecting and interpreting the breakpoints of structural rearrangements yields unparalleled information in comparison to other commonly used first-tier diagnostic methods, such as non-invasive cfDNA screening and microarray analysis, to provide improved genetic counseling for phenotypic outcome in the prenatal setting.
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Affiliation(s)
- Zehra Ordulu
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Tammy Kammin
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Harrison Brand
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA
| | - Vamsee Pillalamarri
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Claire E Redin
- Harvard Medical School, Boston, MA 02115, USA; Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA
| | - Ryan L Collins
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Ian Blumenthal
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Carrie Hanscom
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Shahrin Pereira
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - India Bradley
- Department of Psychiatry, Prenatal Diagnosis Center, David Geffen School of Medicine, University of California, Los Angeles, Medical Plaza, Los Angeles, CA 90095, USA
| | - Barbara F Crandall
- Department of Psychiatry, Prenatal Diagnosis Center, David Geffen School of Medicine, University of California, Los Angeles, Medical Plaza, Los Angeles, CA 90095, USA
| | - Pamela Gerrol
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Mark A Hayden
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Naveed Hussain
- Department of Pediatrics, Connecticut Children's Medical Center, University of Connecticut, Farmington, CT 06030, USA
| | | | - Sibel Kantarci
- Department of Pathology and Laboratory Medicine, UCLA Clinical Genomics Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Brynn Levy
- Department of Pathology and Cell Biology, College of Physicians and Surgeons, Columbia University, New York, NY 10032, USA
| | - Michael J Macera
- New York Presbyterian Hospital, Columbia University Medical Center, New York, NY 10032, USA
| | - Fabiola Quintero-Rivera
- Department of Pathology and Laboratory Medicine, UCLA Clinical Genomics Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Erica Spiegel
- Department of Maternal Fetal Medicine, Columbia University Medical Center, New York, NY 10032, USA
| | - Blair Stevens
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas Medical School at Houston, Houston, TX 77030, USA
| | - Janet E Ulm
- Regional Obstetrical Consultants, Chattanooga, TN 37403, USA
| | - Dorothy Warburton
- Department of Genetics and Development, Columbia University, New York, NY 10032, USA; Department of Pediatrics, Columbia University, New York, NY 10032, USA
| | - Louise E Wilkins-Haug
- Department of Obstetrics, Gynecology, and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115, USA; Harvard Medical School, Boston, MA 02115, USA
| | - Naomi Yachelevich
- Department of Pediatrics, Clinical Genetics Services, New York University School of Medicine, New York, NY 10003, USA
| | - James F Gusella
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA; Department of Genetics, Harvard Medical School, Boson, MA 02115, USA
| | - Michael E Talkowski
- Harvard Medical School, Boston, MA 02115, USA; Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Boston, MA 02142, USA; Departments of Psychiatry and Pathology, Massachusetts General Hospital, Boston, MA 02114, 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 MIT and Harvard, Boston, MA 02142, USA; Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA; Division of Evolution and Genomic Science, School of Biological Sciences, University of Manchester, Manchester Academic Health Science Center, Manchester 03101, UK.
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42
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An Emerging Regulatory Landscape for Skeletal Development. Trends Genet 2016; 32:774-787. [PMID: 27814929 DOI: 10.1016/j.tig.2016.10.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 09/21/2016] [Accepted: 10/04/2016] [Indexed: 02/02/2023]
Abstract
Skeletal development creates the physical framework that shapes our body and its actions. In the past two decades, genetic studies have provided important insights into the molecular processes at play, including the roles of signaling pathways and transcriptional effectors that coordinate an orderly, progressive emergence and expansion of distinct cartilage and bone cell fates in an invariant temporal and spatial pattern for any given skeletal element within that specific vertebrate species. Genome-scale studies have provided additional layers of understanding, moving from individual genes to the gene regulatory landscape, integrating regulatory information through cis-regulatory modules into cell type-specific gene regulatory programs. This review discusses our current understanding of the transcriptional control of mammalian skeletal development, focusing on recent genome-scale studies.
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Formation of new chromatin domains determines pathogenicity of genomic duplications. Nature 2016; 538:265-269. [DOI: 10.1038/nature19800] [Citation(s) in RCA: 455] [Impact Index Per Article: 56.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 08/23/2016] [Indexed: 01/10/2023]
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Xu JX, Kilpatrick N, Baker NL, Penington A, Farlie PG, Tan TY. Clinical and Molecular Characterisation of Children with Pierre Robin Sequence and Additional Anomalies. Mol Syndromol 2016; 7:322-328. [PMID: 27920635 DOI: 10.1159/000449115] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/25/2016] [Indexed: 12/21/2022] Open
Abstract
Pierre Robin Sequence (PRS) is usually classified into syndromic and nonsyndromic groups, with a further subclassification of the nonsyndromic group into isolated PRS and PRS with additional anomalies (PRS-Plus). The aim of this research is to provide an accurate phenotypic characterisation of nonsyndromic PRS, specifically the PRS-Plus subgroup. We sought to examine the frequency of sequence variants in previously defined conserved noncoding elements (CNEs) in the putative enhancer region upstream of SOX9, the regulation of which has been associated with PRS phenotypes. We identified 141 children with nonsyndromic PRS at the Royal Children's Hospital, Melbourne from 1985 to 2012 using 2 databases. Clinical and demographic data were extracted by file review and children categorized as 'isolated PRS' or 'PRS-Plus'. A subset of children with PRS-Plus was selected for detailed phenotyping and DNA sequencing of the upstream SOX9 CNEs. We found 83 children with isolated PRS and 58 with PRS-Plus. The most common PRS-Plus malformations involved the musculoskeletal and ocular systems. The most common coexisting craniofacial malformation was choanal stenosis/atresia. We identified 10 children with a family history of PRS or cleft palate. We found a single nucleotide substitution in a putative GATA1-binding site in one patient, but it was inherited from his phenotypically unaffected mother. PRS-Plus represents a broad phenotypic spectrum with uncertain pathogenesis. Dysmorphology assessment by a clinical geneticist is recommended. SOX9 CNE sequence variants are rare in our cohort and are unlikely to play a significant role in the pathogenesis of PRS-Plus.
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Affiliation(s)
- Jessie X Xu
- Murdoch Childrens Research Institute, University of Melbourne, Melbourne, Vic., Australia; Department of Paediatrics, University of Melbourne, Melbourne, Vic., Australia
| | - Nicky Kilpatrick
- Murdoch Childrens Research Institute, University of Melbourne, Melbourne, Vic., Australia; Department of Paediatrics, University of Melbourne, Melbourne, Vic., Australia; Royal Children's Hospital, Melbourne, Vic., Australia
| | - Naomi L Baker
- Murdoch Childrens Research Institute, University of Melbourne, Melbourne, Vic., Australia
| | - Anthony Penington
- Murdoch Childrens Research Institute, University of Melbourne, Melbourne, Vic., Australia; Department of Paediatrics, University of Melbourne, Melbourne, Vic., Australia; Royal Children's Hospital, Melbourne, Vic., Australia
| | - Peter G Farlie
- Murdoch Childrens Research Institute, University of Melbourne, Melbourne, Vic., Australia; Department of Paediatrics, University of Melbourne, Melbourne, Vic., Australia
| | - Tiong Yang Tan
- Murdoch Childrens Research Institute, University of Melbourne, Melbourne, Vic., Australia; Department of Paediatrics, University of Melbourne, Melbourne, Vic., Australia; Royal Children's Hospital, Melbourne, Vic., Australia; Victorian Clinical Genetics Services, Melbourne, Vic., Australia
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Brinkley JF, Fisher S, Harris MP, Holmes G, Hooper JE, Jabs EW, Jones KL, Kesselman C, Klein OD, Maas RL, Marazita ML, Selleri L, Spritz RA, van Bakel H, Visel A, Williams TJ, Wysocka J, Chai Y. The FaceBase Consortium: a comprehensive resource for craniofacial researchers. Development 2016; 143:2677-88. [PMID: 27287806 PMCID: PMC4958338 DOI: 10.1242/dev.135434] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2016] [Accepted: 05/22/2016] [Indexed: 12/13/2022]
Abstract
The FaceBase Consortium, funded by the National Institute of Dental and Craniofacial Research, National Institutes of Health, is designed to accelerate understanding of craniofacial developmental biology by generating comprehensive data resources to empower the research community, exploring high-throughput technology, fostering new scientific collaborations among researchers and human/computer interactions, facilitating hypothesis-driven research and translating science into improved health care to benefit patients. The resources generated by the FaceBase projects include a number of dynamic imaging modalities, genome-wide association studies, software tools for analyzing human facial abnormalities, detailed phenotyping, anatomical and molecular atlases, global and specific gene expression patterns, and transcriptional profiling over the course of embryonic and postnatal development in animal models and humans. The integrated data visualization tools, faceted search infrastructure, and curation provided by the FaceBase Hub offer flexible and intuitive ways to interact with these multidisciplinary data. In parallel, the datasets also offer unique opportunities for new collaborations and training for researchers coming into the field of craniofacial studies. Here, we highlight the focus of each spoke project and the integration of datasets contributed by the spokes to facilitate craniofacial research.
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Affiliation(s)
- James F Brinkley
- Structural Informatics Group, Department of Biological Structure, University of Washington, Seattle, WA 98195, USA
| | - Shannon Fisher
- Department of Pharmacology and Experimental Therapeutics, Boston University School of Medicine, Boston, MA 02118, USA
| | - Matthew P Harris
- Department of Orthopedic Research, Boston Children's Hospital and Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Greg Holmes
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Joan E Hooper
- Cell and Developmental Biology, School of Medicine, University of Colorado, Aurora, CO 80045, USA
| | - Ethylin Wang Jabs
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Kenneth L Jones
- Department of Biochemistry and Molecular Genetics, School of Medicine, University of Colorado, Aurora, CO 80045, USA
| | - Carl Kesselman
- Information Sciences Institute, Viterbi School of Engineering, University of Southern California, Marina del Rey, CA 90292, USA
| | - Ophir D Klein
- Program in Craniofacial Biology, Departments of Orofacial Sciences and Pediatrics, Institute for Human Genetics, University of California San Francisco, San Francisco, CA 94143, USA
| | - Richard L Maas
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Mary L Marazita
- Center for Craniofacial and Dental Genetics, Department of Oral Biology, School of Dental Medicine, University of Pittsburgh, Pittsburgh, PA 15213, USA Department of Human Genetics, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Licia Selleri
- Program in Craniofacial Biology, Departments of Orofacial Sciences and Pediatrics, Institute for Human Genetics, University of California San Francisco, San Francisco, CA 94143, USA
| | - Richard A Spritz
- Human Medical Genetics and Genomics Program, School of Medicine, University of Colorado, Aurora, CO 80045, USA
| | - Harm van Bakel
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Axel Visel
- Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA 94598, USA School of Natural Sciences, University of California Merced, Merced, CA 95343, USA
| | - Trevor J Williams
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado, Aurora, CO 80045, USA
| | - Joanna Wysocka
- Department of Chemical and Systems Biology and of Developmental Biology, School of Medicine, Stanford University, Stanford, CA 94305, USA
| | - Yang Chai
- Center for Craniofacial Molecular Biology, Herman Ostrow School of Dentistry, University of Southern California, Los Angeles, CA 90033, USA
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Van Otterloo E, Williams T, Artinger KB. The old and new face of craniofacial research: How animal models inform human craniofacial genetic and clinical data. Dev Biol 2016; 415:171-187. [PMID: 26808208 DOI: 10.1016/j.ydbio.2016.01.017] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Revised: 01/16/2016] [Accepted: 01/21/2016] [Indexed: 12/31/2022]
Abstract
The craniofacial skeletal structures that comprise the human head develop from multiple tissues that converge to form the bones and cartilage of the face. Because of their complex development and morphogenesis, many human birth defects arise due to disruptions in these cellular populations. Thus, determining how these structures normally develop is vital if we are to gain a deeper understanding of craniofacial birth defects and devise treatment and prevention options. In this review, we will focus on how animal model systems have been used historically and in an ongoing context to enhance our understanding of human craniofacial development. We do this by first highlighting "animal to man" approaches; that is, how animal models are being utilized to understand fundamental mechanisms of craniofacial development. We discuss emerging technologies, including high throughput sequencing and genome editing, and new animal repository resources, and how their application can revolutionize the future of animal models in craniofacial research. Secondly, we highlight "man to animal" approaches, including the current use of animal models to test the function of candidate human disease variants. Specifically, we outline a common workflow deployed after discovery of a potentially disease causing variant based on a select set of recent examples in which human mutations are investigated in vivo using animal models. Collectively, these topics will provide a pipeline for the use of animal models in understanding human craniofacial development and disease for clinical geneticist and basic researchers alike.
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Affiliation(s)
- Eric Van Otterloo
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
| | - Trevor Williams
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Kristin Bruk Artinger
- Department of Craniofacial Biology, School of Dental Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
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Castori M, Bottillo I, Morlino S, Barone C, Cascone P, Grammatico P, Laino L. Variability in a three-generation family with Pierre Robin sequence, acampomelic campomelic dysplasia, and intellectual disability due to a novel ∼1 Mb deletion upstream of SOX9, and including KCNJ2 and KCNJ16. ACTA ACUST UNITED AC 2015; 106:61-8. [PMID: 26663529 DOI: 10.1002/bdra.23463] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND Campomelic dysplasia and acampomelic campomelic dysplasia (ACD) are allelic disorders due to heterozygous mutations in or around SOX9. Translocations and deletions involving the SOX9 5' regulatory region are rare causes of these disorders, as well as Pierre Robin sequence (PRS) and 46,XY gonadal dysgenesis. Genotype-phenotype correlations are not straightforward due to the complex epigenetic regulation of SOX9 expression during development. METHODS We report a three-generation pedigree with a novel ∼1 Mb deletion upstream of SOX9 and including KCNJ2 and KCNJ16, and ascertained for dominant transmission of PRS. RESULTS Further characterization of the family identified subtle appendicular anomalies and a variable constellation of axial skeletal features evocative of ACD in several members. Affected males showed learning disability. CONCLUSION The identified deletion was smaller than all other chromosome rearrangements associated with ACD. Comparison with other reported translocations and deletions involving this region allowed further refining of genotype-phenotype correlations and an update of the smallest regions of overlap associated with the different phenotypes. Intrafamilial variability in this pedigree suggests a phenotypic continuity between ACD and PRS in patients carrying mutations in the SOX9 5' regulatory region.
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Affiliation(s)
- Marco Castori
- Division of Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Rome, Italy
| | - Irene Bottillo
- Division of Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Rome, Italy
| | - Silvia Morlino
- Division of Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Rome, Italy
| | - Chiara Barone
- Center for Genetic Counseling and Reproductive Teratology, Maternal and Child Health Department, Garibaldi Nesima Hospital, Catania, Italy
| | - Piero Cascone
- Division of Maxillo-Facial Surgery, Sapienza University, Policlinico Umberto I Hospital, Rome, Italy
| | | | - Paola Grammatico
- Division of Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Rome, Italy
| | - Luigi Laino
- Division of Medical Genetics, Department of Molecular Medicine, Sapienza University, San Camillo-Forlanini Hospital, Rome, Italy
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Abstract
PURPOSE OF REVIEW Clinical diagnostic sequencing currently focuses on identifying causal mutations in the exome, wherein most disease-causing mutations are known to occur. The rest of the genome is mostly comprised of regulatory elements that control gene expression, but these have remained largely unexplored in clinical diagnostics due to the high cost of whole genome sequencing and interpretive challenges. The purpose of this review is to illustrate examples of diseases caused by mutations in regulatory elements and introduce the diagnostic potential for whole genome sequencing. Different classes of functional elements and chromatin structure are described to provide the clinician with a foundation for understanding the basis of these mutations. RECENT FINDINGS The utilization of whole-genome sequence data, epigenomic maps and induced pluripotent stem (IPS) cell technologies facilitated the discovery that mutations in the pancreas-specific transcription factor 1a enhancer can cause isolated pancreatic agenesis. High resolution array comparative genomic hybridisation (CGH), whole-genome sequencing, maps of 3-D chromatin architecture, and mouse models generated using clustered regularly interspaced short palindromic repeats (CRISPR)/Cas were used to show that disruption of topological-associated domain boundary elements cause limb defects. Structural variants that reposition enhancers in somatic cells have also been described in cancer. SUMMARY Although not ready for diagnostics, new technologies, epigenomic maps, and improved knowledge of chromatin architecture will soon enable a better understanding and diagnostic solutions for currently unexplained genetic disorders.
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Abstract
The formation of the face and skull involves a complex series of developmental events mediated by cells derived from the neural crest, endoderm, mesoderm, and ectoderm. Although vertebrates boast an enormous diversity of adult facial morphologies, the fundamental signaling pathways and cellular events that sculpt the nascent craniofacial skeleton in the embryo have proven to be highly conserved from fish to man. The zebrafish Danio rerio, a small freshwater cyprinid fish from eastern India, has served as a popular model of craniofacial development since the 1990s. Unique strengths of the zebrafish model include a simplified skeleton during larval stages, access to rapidly developing embryos for live imaging, and amenability to transgenesis and complex genetics. In this chapter, we describe the anatomy of the zebrafish craniofacial skeleton; its applications as models for the mammalian jaw, middle ear, palate, and cranial sutures; the superior imaging technology available in fish that has provided unprecedented insights into the dynamics of facial morphogenesis; the use of the zebrafish to decipher the genetic underpinnings of craniofacial biology; and finally a glimpse into the most promising future applications of zebrafish craniofacial research.
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Poot M, Haaf T. Mechanisms of Origin, Phenotypic Effects and Diagnostic Implications of Complex Chromosome Rearrangements. Mol Syndromol 2015; 6:110-34. [PMID: 26732513 DOI: 10.1159/000438812] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/23/2015] [Indexed: 01/08/2023] Open
Abstract
Complex chromosome rearrangements (CCRs) are currently defined as structural genome variations that involve more than 2 chromosome breaks and result in exchanges of chromosomal segments. They are thought to be extremely rare, but their detection rate is rising because of improvements in molecular cytogenetic technology. Their population frequency is also underestimated, since many CCRs may not elicit a phenotypic effect. CCRs may be the result of fork stalling and template switching, microhomology-mediated break-induced repair, breakage-fusion-bridge cycles, or chromothripsis. Patients with chromosomal instability syndromes show elevated rates of CCRs due to impaired DNA double-strand break responses during meiosis. Therefore, the putative functions of the proteins encoded by ATM, BLM, WRN, ATR, MRE11, NBS1, and RAD51 in preventing CCRs are discussed. CCRs may exert a pathogenic effect by either (1) gene dosage-dependent mechanisms, e.g. haploinsufficiency, (2) mechanisms based on disruption of the genomic architecture, such that genes, parts of genes or regulatory elements are truncated, fused or relocated and thus their interactions disturbed - these mechanisms will predominantly affect gene expression - or (3) mixed mutation mechanisms in which a CCR on one chromosome is combined with a different type of mutation on the other chromosome. Such inferred mechanisms of pathogenicity need corroboration by mRNA sequencing. Also, future studies with in vitro models, such as inducible pluripotent stem cells from patients with CCRs, and transgenic model organisms should substantiate current inferences regarding putative pathogenic effects of CCRs. The ramifications of the growing body of information on CCRs for clinical and experimental genetics and future treatment modalities are briefly illustrated with 2 cases, one of which suggests KDM4C (JMJD2C) as a novel candidate gene for mental retardation.
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Affiliation(s)
- Martin Poot
- Department of Human Genetics, University of Würzburg, Würzburg, Germany
| | - Thomas Haaf
- Department of Human Genetics, University of Würzburg, Würzburg, Germany
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