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Lipinski RJ, Krauss RS. Gene-environment interactions in birth defect etiology: Challenges and opportunities. Curr Top Dev Biol 2023; 152:1-30. [PMID: 36707208 PMCID: PMC9942595 DOI: 10.1016/bs.ctdb.2022.10.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Birth defects are relatively common congenital outcomes that significantly impact affected individuals, their families, and communities. Effective development and deployment of prevention and therapeutic strategies for these conditions requires sufficient understanding of etiology, including underlying genetic and environmental causes. Tremendous progress has been made in defining the genetic basis of familial and syndromic forms of birth defects. However, the majority of birth defect cases are considered nonsyndromic and thought to result from multifactorial gene-environment interactions. While substantial advances have been made in elucidating the genetic landscape of these etiologically complex conditions, significant biological and technical constraints have stymied progress toward a refined knowledge of environmental risk factors. Defining specific gene-environment interactions in birth defect etiology is even more challenging. However, progress has been made, including demonstration of critical proofs of concept and development of new conceptual and technical approaches for resolving complex gene-environment interactions. In this review, we discuss current views of multifactorial birth defect etiology, comparing them with other diseases that also involve gene-environment interactions, including primary immunodeficiency and cancer. We describe how various model systems have illuminated mechanisms of multifactorial etiology and these models' individual strengths and weaknesses. Finally, suggestions for areas of future emphasis are proposed.
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Affiliation(s)
- Robert J. Lipinski
- Department of Comparative Biosciences, School of Veterinary Medicine, University of Wisconsin, Madison, WI, United States,Corresponding authors: ;
| | - Robert S. Krauss
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, United States,Corresponding authors: ;
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2
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Brain Organization and Human Diseases. Cells 2022; 11:cells11101642. [PMID: 35626679 PMCID: PMC9139716 DOI: 10.3390/cells11101642] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 05/09/2022] [Accepted: 05/12/2022] [Indexed: 02/06/2023] Open
Abstract
The cortex is a highly organized structure that develops from the caudal regions of the segmented neural tube. Its spatial organization sets the stage for future functional arealization. Here, we suggest using a developmental perspective to describe and understand the etiology of common cortical malformations and their manifestation in the human brain.
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3
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Barratt KS, Drover KA, Thomas ZM, Arkell RM. Patterning of the antero-ventral mammalian brain: Lessons from holoprosencephaly comparative biology in man and mouse. WIREs Mech Dis 2022; 14:e1552. [PMID: 35137563 DOI: 10.1002/wsbm.1552] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 11/30/2021] [Accepted: 12/21/2021] [Indexed: 12/13/2022]
Abstract
Adult form and function are dependent upon the activity of specialized signaling centers that act early in development at the embryonic midline. These centers instruct the surrounding cells to adopt a positional fate and to form the patterned structures of the phylotypic embryo. Abnormalities in these processes have devastating consequences for the individual, as exemplified by holoprosencephaly in which anterior midline development fails, leading to structural defects of the brain and/or face. In the 25 years since the first association between human holoprosencephaly and the sonic hedgehog gene, a combination of human and animal genetic studies have enhanced our understanding of the genetic and embryonic causation of this congenital defect. Comparative biology has extended the holoprosencephaly network via the inclusion of gene mutations from multiple signaling pathways known to be required for anterior midline formation. It has also clarified aspects of holoprosencephaly causation, showing that it arises when a deleterious variant is present within a permissive genome, and that environmental factors, as well as embryonic stochasticity, influence the phenotypic outcome of the variant. More than two decades of research can now be distilled into a framework of embryonic and genetic causation. This framework means we are poised to move beyond our current understanding of variants in signaling pathway molecules. The challenges now at the forefront of holoprosencephaly research include deciphering how the mutation of genes involved in basic cell processes can also cause holoprosencephaly, determining the important constituents of the holoprosencephaly permissive genome, and identifying environmental compounds that promote holoprosencephaly. This article is categorized under: Congenital Diseases > Stem Cells and Development Congenital Diseases > Genetics/Genomics/Epigenetics Congenital Diseases > Molecular and Cellular Physiology Congenital Diseases > Environmental Factors.
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Affiliation(s)
- Kristen S Barratt
- John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Kyle A Drover
- John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Zoe M Thomas
- John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory, Australia
| | - Ruth M Arkell
- John Curtin School of Medical Research, The Australian National University, Canberra, Australian Capital Territory, Australia
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4
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Lo HF, Hong M, Krauss RS. Concepts in Multifactorial Etiology of Developmental Disorders: Gene-Gene and Gene-Environment Interactions in Holoprosencephaly. Front Cell Dev Biol 2022; 9:795194. [PMID: 35004690 PMCID: PMC8727999 DOI: 10.3389/fcell.2021.795194] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 11/29/2021] [Indexed: 12/17/2022] Open
Abstract
Many common developmental disorders are thought to arise from a complex set of genetic and environmental risk factors. These factors interact with each other to affect the strength and duration of key developmental signaling pathways, thereby increasing the possibility that they fail to achieve the thresholds required for normal embryonic patterning. One such disorder, holoprosencephaly (HPE), serves as a useful model system in understanding various forms of multifactorial etiology. Genomic analysis of HPE cases, epidemiology, and mechanistic studies of animal models have illuminated multiple potential ways that risk factors interact to produce adverse developmental outcomes. Among these are: 1) interactions between driver and modifier genes; 2) oligogenic inheritance, wherein each parent provides predisposing variants in one or multiple distinct loci; 3) interactions between genetic susceptibilities and environmental risk factors that may be insufficient on their own; and 4) interactions of multiple genetic variants with multiple non-genetic risk factors. These studies combine to provide concepts that illuminate HPE and are also applicable to additional disorders with complex etiology, including neural tube defects, congenital heart defects, and oro-facial clefting.
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Affiliation(s)
- Hsiao-Fan Lo
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Mingi Hong
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
| | - Robert S Krauss
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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5
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Loo CKC, Pearen MA, Ramm GA. The Role of Sonic Hedgehog in Human Holoprosencephaly and Short-Rib Polydactyly Syndromes. Int J Mol Sci 2021; 22:ijms22189854. [PMID: 34576017 PMCID: PMC8468456 DOI: 10.3390/ijms22189854] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/03/2021] [Accepted: 09/09/2021] [Indexed: 12/18/2022] Open
Abstract
The Hedgehog (HH) signalling pathway is one of the major pathways controlling cell differentiation and proliferation during human development. This pathway is complex, with HH function influenced by inhibitors, promotors, interactions with other signalling pathways, and non-genetic and cellular factors. Many aspects of this pathway are not yet clarified. The main features of Sonic Hedgehog (SHH) signalling are discussed in relation to its function in human development. The possible role of SHH will be considered using examples of holoprosencephaly and short-rib polydactyly (SRP) syndromes. In these syndromes, there is wide variability in phenotype even with the same genetic mutation, so that other factors must influence the outcome. SHH mutations were the first identified genetic causes of holoprosencephaly, but many other genes and environmental factors can cause malformations in the holoprosencephaly spectrum. Many patients with SRP have genetic defects affecting primary cilia, structures found on most mammalian cells which are thought to be necessary for canonical HH signal transduction. Although SHH signalling is affected in both these genetic conditions, there is little overlap in phenotype. Possible explanations will be canvassed, using data from published human and animal studies. Implications for the understanding of SHH signalling in humans will be discussed.
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Affiliation(s)
- Christine K. C. Loo
- South Eastern Area Laboratory Services, Department of Anatomical Pathology, NSW Health Pathology, Prince of Wales Hospital, Sydney, NSW 2031, Australia
- Correspondence: ; Tel.: +61-2-93829015
| | - Michael A. Pearen
- Hepatic Fibrosis Group, Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia; (M.A.P.); (G.A.R.)
| | - Grant A. Ramm
- Hepatic Fibrosis Group, Department of Cell and Molecular Biology, QIMR Berghofer Medical Research Institute, Brisbane, QLD 4006, Australia; (M.A.P.); (G.A.R.)
- Faculty of Medicine, The University of Queensland, Brisbane, QLD 4006, Australia
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6
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de Castro VF, Mattos D, de Carvalho FM, Cavalcanti DP, Duenas-Roque MM, Llerena J, Cosentino VR, Honjo RS, Leite JCL, Sanseverino MT, de Souza MPA, Bernardi P, Bolognese AM, Santana da Silva LC, Barbero P, Correia PS, Bueno LSM, Savastano CP, Orioli IM. New SHH and Known SIX3 Variants in a Series of Latin American Patients with Holoprosencephaly. Mol Syndromol 2021; 12:219-233. [PMID: 34421500 DOI: 10.1159/000515044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 02/04/2021] [Indexed: 11/19/2022] Open
Abstract
Holoprosencephaly (HPE) is the failure of the embryonic forebrain to develop into 2 hemispheres promoting midline cerebral and facial defects. The wide phenotypic variability and causal heterogeneity make genetic counseling difficult. Heterozygous variants with incomplete penetrance and variable expressivity in the SHH, SIX3, ZIC2, and TGIF1 genes explain ∼25% of the known causes of nonchromosomal HPE. We studied these 4 genes and clinically described 27 Latin American families presenting with nonchromosomal HPE. Three new SHH variants and a third known SIX3 likely pathogenic variant found by Sanger sequencing explained 15% of our cases. Genotype-phenotype correlation in these 4 families and published families with identical or similar driver gene, mutated domain, conservation of residue in other species, and the type of variant explain the pathogenicity but not the phenotypic variability. Nine patients, including 2 with SHH pathogenic variants, presented benign variants of the SHH, SIX3, ZIC2, and TGIF1 genes with potential alteration of splicing, a causal proposition in need of further studies. Finding more families with the same SIX3 variant may allow further identification of genetic or environmental modifiers explaining its variable phenotypic expression.
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Affiliation(s)
- Viviane Freitas de Castro
- ECLAMC at Departamento de Genética, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Genética Médica Populacional INAGEMP, Porto Alegre, Brazil
| | - Daniel Mattos
- ECLAMC at Departamento de Genética, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Genética Médica Populacional INAGEMP, Porto Alegre, Brazil
| | - Flavia Martinez de Carvalho
- Instituto Nacional de Genética Médica Populacional INAGEMP, Porto Alegre, Brazil.,ECLAMC at Laboratorio Epidemiol. Malformações Congênitas, IOC/FIOCRUZ, Rio de Janeiro, Brazil
| | | | - Milagros M Duenas-Roque
- ECLAMC at Servicio de Genética, Hospital Nacional Edgardo Rebagliati Martins/EsSalud, Lima, Peru
| | - Juan Llerena
- Instituto Nacional de Genética Médica Populacional INAGEMP, Porto Alegre, Brazil.,ECLAMC at Centro de Genética Médica, IFF/FIOCRUZ, Rio de Janeiro, Brazil
| | | | | | | | | | | | - Pricila Bernardi
- Núcleo de Genética Clínica, Departamento de Clínica Médica/UFSC, Florianópolis, Brazil
| | - Ana Maria Bolognese
- Departamento de Ortodontia, Faculdade de Odontologia/UFRJ, Rio de Janeiro, Brazil
| | - Luiz Carlos Santana da Silva
- Instituto Nacional de Genética Médica Populacional INAGEMP, Porto Alegre, Brazil.,Laboratório de Erros Inatos de Metabolismo, Instituto de Ciências Biológicas/UFP, Belém, Brazil
| | - Pablo Barbero
- RENAC, Centro Nacional de Genética Médica Dr. Eduardo E. Castilla/MS, Buenos Aires, Argentina
| | | | | | | | - Iêda Maria Orioli
- ECLAMC at Departamento de Genética, UFRJ, Rio de Janeiro, Brazil.,Instituto Nacional de Genética Médica Populacional INAGEMP, Porto Alegre, Brazil
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7
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Yan X, Wu HH, Chen Z, Du GW, Bai XJ, Tuoheti K, Liu TZ. Construction and Validation of an Autophagy-Related Prognostic Signature and a Nomogram for Bladder Cancer. Front Oncol 2021; 11:632387. [PMID: 34221960 PMCID: PMC8252967 DOI: 10.3389/fonc.2021.632387] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Accepted: 05/05/2021] [Indexed: 12/13/2022] Open
Abstract
Objective Bladder cancer (BC) is one of the top ten cancers endangering human health but we still lack accurate tools for BC patients’ risk stratification. This study aimed to develop an autophagy-related signature that could predict the prognosis of BC. In order to provide clinical doctors with a visual tool that could precisely predict the survival probability of BC patients, we also attempted to establish a nomogram based on the risk signature. Methods We screened out autophagy-related genes (ARGs) combining weighted gene co-expression network analysis (WGCNA) and differentially expressed gene (DEG) in BC. Based on the screened ARGs, we performed survival analysis and Cox regression analysis to identify potential prognostic biomarkers. A risk signature based on the prognostic ARGs by multivariate Cox regression analysis was established, which was validated by using seven datasets. To provide clinical doctors with a useful tool for survival possibility prediction, a nomogram assessed by the ARG-based signature and clinicopathological features was constructed, verified using four independent datasets. Results Three prognostic biomarkers including BOC (P = 0.008, HR = 1.104), FGF7(P = 0.030, HR = 1.066), and MAP1A (P = 0.001, HR = 1.173) were identified and validated. An autophagy-related risk signature was established and validated. This signature could act as an independent prognostic feature in patients with BC (P = 0.047, HR = 1.419). We then constructed two nomograms with and without ARG-based signature and subsequent analysis indicated that the nomogram with ARG signature showed high accuracy for overall survival probability prediction of patients with BC (C-index = 0.732, AUC = 0.816). These results proved that the ARG signature improved the clinical net benefit of the standard model based on clinicopathological features (age, pathologic stage). Conclusions Three ARGs were identified as prognosis biomarkers in BC. An ARG-based signature was established for the first time, showing strong potential for prognosis prediction in BC. This signature was proven to improve the clinical net benefit of the standard model. A nomogram was established using this signature, which could lead to more effective prognosis prediction for BC patients.
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Affiliation(s)
- Xin Yan
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Hua-Hui Wu
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Zhao Chen
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Guo-Wei Du
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Xiao-Jie Bai
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Kurerban Tuoheti
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Tong-Zu Liu
- Department of Urology, Zhongnan Hospital of Wuhan University, Wuhan, China
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8
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Echevarría-Andino ML, Allen BL. The hedgehog co-receptor BOC differentially regulates SHH signaling during craniofacial development. Development 2020; 147:dev.189076. [PMID: 33060130 DOI: 10.1242/dev.189076] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 10/06/2020] [Indexed: 12/31/2022]
Abstract
The Hedgehog (HH) pathway controls multiple aspects of craniofacial development. HH ligands signal through the canonical receptor PTCH1, and three co-receptors: GAS1, CDON and BOC. Together, these co-receptors are required during embryogenesis to mediate proper HH signaling. Here, we investigated the individual and combined contributions of GAS1, CDON and BOC to HH-dependent mammalian craniofacial development. Notably, individual deletion of either Gas1 or Cdon results in variable holoprosencephaly phenotypes in mice, even on a congenic background. In contrast, we find that Boc deletion results in facial widening that correlates with increased HH target gene expression. In addition, Boc deletion in a Gas1 null background partially ameliorates the craniofacial defects observed in Gas1 single mutants; a phenotype that persists over developmental time, resulting in significant improvements to a subset of craniofacial structures. This contrasts with HH-dependent phenotypes in other tissues that significantly worsen following combined deletion of Gas1 and Boc Together, these data indicate that BOC acts as a multi-functional regulator of HH signaling during craniofacial development, alternately promoting or restraining HH pathway activity in a tissue-specific fashion.
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Affiliation(s)
| | - Benjamin L Allen
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, MI 48109, USA
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9
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Nagai-Tanima M, Hong S, Hu P, Carrington B, Sood R, Roessler E, Muenke M. Rare hypomorphic human variation in the heptahelical domain of SMO contributes to holoprosencephaly phenotypes. Hum Mutat 2020; 41:2105-2118. [PMID: 32906187 DOI: 10.1002/humu.24103] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 08/14/2020] [Accepted: 08/28/2020] [Indexed: 12/19/2022]
Abstract
Holoprosencephaly (HPE) is the most common congenital anomaly affecting the forebrain and face in humans and occurs as frequently as 1:250 conceptions or 1:10,000 livebirths. Sonic Hedgehog signaling molecule is one of the best characterized HPE genes that plays crucial roles in numerous developmental processes including midline neural patterning and craniofacial development. The Frizzled class G-protein coupled receptor Smoothened (SMO), whose signaling activity is tightly regulated, is the sole obligate transducer of Hedgehog-related signals. However, except for previous reports of somatic oncogenic driver mutations in human cancers (or mosaic tumors in rare syndromes), any potential disease-related role of SMO genetic variation in humans is largely unknown. To our knowledge, ours is the first report of a human hypomorphic variant revealed by functional testing of seven distinct nonsynonymous SMO variants derived from HPE molecular and clinical data. Here we describe several zebrafish bioassays developed and guided by a systems biology analysis. This analysis strategy, and detection of hypomorphic variation in human SMO, demonstrates the necessity of integrating the genomic variant findings in HPE probands with other components of the Hedgehog gene regulatory network in overall medical interpretations.
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Affiliation(s)
- Momoko Nagai-Tanima
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Sungkook Hong
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Ping Hu
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Blake Carrington
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
- Zebrafish Core, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Raman Sood
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
- Zebrafish Core, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Erich Roessler
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Maximilian Muenke
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
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10
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Hamdi-Rozé H, Ware M, Guyodo H, Rizzo A, Ratié L, Rupin M, Carré W, Kim A, Odent S, Dubourg C, David V, de Tayrac M, Dupé V. Disrupted Hypothalamo-Pituitary Axis in Association With Reduced SHH Underlies the Pathogenesis of NOTCH-Deficiency. J Clin Endocrinol Metab 2020; 105:5836893. [PMID: 32403133 DOI: 10.1210/clinem/dgaa249] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/03/2020] [Accepted: 05/10/2020] [Indexed: 12/16/2022]
Abstract
CONTEXT In human, Sonic hedgehog (SHH) haploinsufficiency is the predominant cause of holoprosencephaly, a structural malformation of the forebrain midline characterized by phenotypic heterogeneity and incomplete penetrance. The NOTCH signaling pathway has recently been associated with holoprosencephaly in humans, but the precise mechanism involving NOTCH signaling during early brain development remains unknown. OBJECTIVE The aim of this study was to evaluate the relationship between SHH and NOTCH signaling to determine the mechanism by which NOTCH dysfunction could cause midline malformations of the forebrain. DESIGN In this study, we have used a chemical inhibition approach in the chick model and a genetic approach in the mouse model. We also reported results obtained from the clinical diagnosis of a cohort composed of 141 holoprosencephaly patients. RESULTS We demonstrated that inhibition of NOTCH signaling in chick embryos as well as in mouse embryos induced a specific downregulation of SHH in the anterior hypothalamus. Our data in the mouse also revealed that the pituitary gland was the most sensitive tissue to Shh insufficiency and that haploinsufficiency of the SHH and NOTCH signaling pathways synergized to produce a malformed pituitary gland. Analysis of a large holoprosencephaly cohort revealed that some patients possessed multiple heterozygous mutations in several regulators of both pathways. CONCLUSIONS These results provided new insights into molecular mechanisms underlying the extreme phenotypic variability observed in human holoprosencephaly. They showed how haploinsufficiency of the SHH and NOTCH activity could contribute to specific congenital hypopituitarism that was associated with a sella turcica defect.
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Affiliation(s)
- Houda Hamdi-Rozé
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
- Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Michelle Ware
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
| | - Hélène Guyodo
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
| | - Aurélie Rizzo
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
| | - Leslie Ratié
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
| | - Maïlys Rupin
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
| | - Wilfrid Carré
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
- Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Artem Kim
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
| | - Sylvie Odent
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
- Service de Génétique Clinique, CHU, Rennes, France
| | - Christèle Dubourg
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
- Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Véronique David
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
| | - Marie de Tayrac
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
- Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Valérie Dupé
- Univ Rennes, CNRS, IGDR - Institut de Génétique et Développement de Rennes - UMR6290, Rennes, France
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11
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Sasai N, Toriyama M, Kondo T. Hedgehog Signal and Genetic Disorders. Front Genet 2019; 10:1103. [PMID: 31781166 PMCID: PMC6856222 DOI: 10.3389/fgene.2019.01103] [Citation(s) in RCA: 81] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 10/11/2019] [Indexed: 12/12/2022] Open
Abstract
The hedgehog (Hh) family comprises sonic hedgehog (Shh), Indian hedgehog (Ihh), and desert hedgehog (Dhh), which are versatile signaling molecules involved in a wide spectrum of biological events including cell differentiation, proliferation, and survival; establishment of the vertebrate body plan; and aging. These molecules play critical roles from embryogenesis to adult stages; therefore, alterations such as abnormal expression or mutations of the genes involved and their downstream factors cause a variety of genetic disorders at different stages. The Hh family involves many signaling mediators and functions through complex mechanisms, and achieving a comprehensive understanding of the entire signaling system is challenging. This review discusses the signaling mediators of the Hh pathway and their functions at the cellular and organismal levels. We first focus on the roles of Hh signaling mediators in signal transduction at the cellular level and the networks formed by these factors. Then, we analyze the spatiotemporal pattern of expression of Hh pathway molecules in tissues and organs, and describe the phenotypes of mutant mice. Finally, we discuss the genetic disorders caused by malfunction of Hh signaling-related molecules in humans.
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Affiliation(s)
- Noriaki Sasai
- Developmental Biomedical Science, Division of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Japan
| | - Michinori Toriyama
- Systems Neurobiology and Medicine, Division of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Japan
- Department of Biomedical Chemistry, School of Science and Technology, Kwansei Gakuin University, Sanda, Japan
| | - Toru Kondo
- Division of Stem Cell Biology, Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
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12
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Kim A, Savary C, Dubourg C, Carré W, Mouden C, Hamdi-Rozé H, Guyodo H, Douce JL, Pasquier L, Flori E, Gonzales M, Bénéteau C, Boute O, Attié-Bitach T, Roume J, Goujon L, Akloul L, Odent S, Watrin E, Dupé V, de Tayrac M, David V. Integrated clinical and omics approach to rare diseases: novel genes and oligogenic inheritance in holoprosencephaly. Brain 2019; 142:35-49. [PMID: 30508070 DOI: 10.1093/brain/awy290] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 09/28/2018] [Indexed: 12/27/2022] Open
Abstract
Holoprosencephaly is a pathology of forebrain development characterized by high phenotypic heterogeneity. The disease presents with various clinical manifestations at the cerebral or facial levels. Several genes have been implicated in holoprosencephaly but its genetic basis remains unclear: different transmission patterns have been described including autosomal dominant, recessive and digenic inheritance. Conventional molecular testing approaches result in a very low diagnostic yield and most cases remain unsolved. In our study, we address the possibility that genetically unsolved cases of holoprosencephaly present an oligogenic origin and result from combined inherited mutations in several genes. Twenty-six unrelated families, for whom no genetic cause of holoprosencephaly could be identified in clinical settings [whole exome sequencing and comparative genomic hybridization (CGH)-array analyses], were reanalysed under the hypothesis of oligogenic inheritance. Standard variant analysis was improved with a gene prioritization strategy based on clinical ontologies and gene co-expression networks. Clinical phenotyping and exploration of cross-species similarities were further performed on a family-by-family basis. Statistical validation was performed on 248 ancestrally similar control trios provided by the Genome of the Netherlands project and on 574 ancestrally matched controls provided by the French Exome Project. Variants of clinical interest were identified in 180 genes significantly associated with key pathways of forebrain development including sonic hedgehog (SHH) and primary cilia. Oligogenic events were observed in 10 families and involved both known and novel holoprosencephaly genes including recurrently mutated FAT1, NDST1, COL2A1 and SCUBE2. The incidence of oligogenic combinations was significantly higher in holoprosencephaly patients compared to two control populations (P < 10-9). We also show that depending on the affected genes, patients present with particular clinical features. This study reports novel disease genes and supports oligogenicity as clinically relevant model in holoprosencephaly. It also highlights key roles of SHH signalling and primary cilia in forebrain development. We hypothesize that distinction between different clinical manifestations of holoprosencephaly lies in the degree of overall functional impact on SHH signalling. Finally, we underline that integrating clinical phenotyping in genetic studies is a powerful tool to specify the clinical relevance of certain mutations.
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Affiliation(s)
- Artem Kim
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Clara Savary
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Christèle Dubourg
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France.,Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Wilfrid Carré
- Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Charlotte Mouden
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Houda Hamdi-Rozé
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France.,Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Hélène Guyodo
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Jerome Le Douce
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | | | | | | | - Elisabeth Flori
- Laboratoire de Cytogénétique, Cytologie et Histologie Quantitative, Hôpital de Hautepierre, HUS, Strasbourg, France
| | - Marie Gonzales
- Service de Génétique et Embryologie Médicales, Hôpital Armand Trousseau, Paris, France
| | | | | | - Tania Attié-Bitach
- Service d'Histologie-Embryologie-Cytogénétique, Hôpital Necker-Enfants-Malades, Université Paris Descartes, 149, rue de Sèvres, Paris, France
| | - Joelle Roume
- Department of Clinical Genetics, Centre de Référence “AnDDI Rares”, Poissy Hospital GHU PIFO, Poissy, France
| | | | - Linda Akloul
- Service de Génétique Clinique, CHU, Rennes, France
| | - Sylvie Odent
- Service de Génétique Clinique, CHU, Rennes, France
| | - Erwan Watrin
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Valérie Dupé
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France
| | - Marie de Tayrac
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France.,Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Véronique David
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F-35000 Rennes, France.,Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
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13
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Zakaria M, Ferent J, Hristovska I, Laouarem Y, Zahaf A, Kassoussi A, Mayeur ME, Pascual O, Charron F, Traiffort E. The Shh receptor Boc is important for myelin formation and repair. Development 2019; 146:146/9/dev172502. [PMID: 31048318 DOI: 10.1242/dev.172502] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 03/28/2019] [Indexed: 12/25/2022]
Abstract
Myelination leads to the formation of myelin sheaths surrounding neuronal axons and is crucial for function, plasticity and repair of the central nervous system (CNS). It relies on the interaction of the axons and the oligodendrocytes: the glial cells producing CNS myelin. Here, we have investigated the role of a crucial component of the Sonic hedgehog (Shh) signalling pathway, the co-receptor Boc, in developmental and repairing myelination. During development, Boc mutant mice display a transient decrease in oligodendroglial cell density together with delayed myelination. Despite recovery of oligodendroglial cells at later stages, adult mutants still exhibit a lower production of myelin basic protein correlated with a significant decrease in the calibre of callosal axons and a reduced amount of the neurofilament NF-M. During myelin repair, the altered OPC differentiation observed in the mutant is reminiscent of the phenotype observed after blockade of Shh signalling. In addition, Boc mutant microglia/macrophages unexpectedly exhibit the apparent inability to transition from a highly to a faintly ramified morphology in vivo Altogether, these results identify Boc as an important component of myelin formation and repair.
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Affiliation(s)
- Mary Zakaria
- INSERM-University Paris-Sud/Paris-Saclay; Diseases and Hormones of the Nervous System, U1195, 80 rue du Général Leclerc, F-94276, Le Kremlin-Bicêtre, France
| | - Julien Ferent
- IRCM, Molecular Biology of Neural Development, 110 Pine Avenue West, Montreal, Quebec H2W 1R7, Canada; Department of Medicine, University of Montreal, Montreal, Quebec, Canada; McGill University, Montreal, Quebec, Canada
| | - Ines Hristovska
- Institut NeuroMyoGène CNRS UMR 5310-INSERM U1217-Université Claude Bernard Lyon 1, Faculté de Médecine et de Pharmacie 69008 Lyon, France
| | - Yousra Laouarem
- INSERM-University Paris-Sud/Paris-Saclay; Diseases and Hormones of the Nervous System, U1195, 80 rue du Général Leclerc, F-94276, Le Kremlin-Bicêtre, France
| | - Amina Zahaf
- INSERM-University Paris-Sud/Paris-Saclay; Diseases and Hormones of the Nervous System, U1195, 80 rue du Général Leclerc, F-94276, Le Kremlin-Bicêtre, France
| | - Abdelmoumen Kassoussi
- INSERM-University Paris-Sud/Paris-Saclay; Diseases and Hormones of the Nervous System, U1195, 80 rue du Général Leclerc, F-94276, Le Kremlin-Bicêtre, France
| | - Marie-Eve Mayeur
- Institut NeuroMyoGène CNRS UMR 5310-INSERM U1217-Université Claude Bernard Lyon 1, Faculté de Médecine et de Pharmacie 69008 Lyon, France
| | - Olivier Pascual
- Institut NeuroMyoGène CNRS UMR 5310-INSERM U1217-Université Claude Bernard Lyon 1, Faculté de Médecine et de Pharmacie 69008 Lyon, France
| | - Frederic Charron
- IRCM, Molecular Biology of Neural Development, 110 Pine Avenue West, Montreal, Quebec H2W 1R7, Canada; Department of Medicine, University of Montreal, Montreal, Quebec, Canada; McGill University, Montreal, Quebec, Canada
| | - Elisabeth Traiffort
- INSERM-University Paris-Sud/Paris-Saclay; Diseases and Hormones of the Nervous System, U1195, 80 rue du Général Leclerc, F-94276, Le Kremlin-Bicêtre, France
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14
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Hong S, Hu P, Roessler E, Hu T, Muenke M. Loss-of-function mutations in FGF8 can be independent risk factors for holoprosencephaly. Hum Mol Genet 2019; 27:1989-1998. [PMID: 29584859 DOI: 10.1093/hmg/ddy106] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Accepted: 03/19/2018] [Indexed: 12/27/2022] Open
Abstract
The utilization of next generation sequencing has been shown to accelerate gene discovery in human disease. However, our confidence in the correct disease-associations of rare variants continues to depend on functional analysis. Here, we employ a sensitive assay of human FGF8 variants in zebrafish to demonstrate that the spectrum of isoforms of FGF8 produced by alternative splicing can provide key insights into the genetic susceptibility to human malformations. In addition, we describe novel mutations in the FGF core structure that have both subtle and profound effects on ligand posttranslational processing and biological activity. Finally, we solve a case of apparent digenic inheritance of novel variants in SHH and FGF8, two genes known to functionally coregulate each other in the developing forebrain, as a simpler case of FGF8 diminished function.
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Affiliation(s)
- Sungkook Hong
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-3717, USA
| | - Ping Hu
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-3717, USA
| | - Erich Roessler
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-3717, USA
| | - Tommy Hu
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-3717, USA
| | - Maximilian Muenke
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-3717, USA
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15
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Merkuri F, Fish JL. Developmental processes regulate craniofacial variation in disease and evolution. Genesis 2018; 57:e23249. [PMID: 30207415 DOI: 10.1002/dvg.23249] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/29/2018] [Accepted: 09/06/2018] [Indexed: 12/30/2022]
Abstract
Variation in development mediates phenotypic differences observed in evolution and disease. Although the mechanisms underlying phenotypic variation are still largely unknown, recent research suggests that variation in developmental processes may play a key role. Developmental processes mediate genotype-phenotype relationships and consequently play an important role regulating phenotypes. In this review, we provide an example of how shared and interacting developmental processes may explain convergence of phenotypes in spliceosomopathies and ribosomopathies. These data also suggest a shared pathway to disease treatment. We then discuss three major mechanisms that contribute to variation in developmental processes: genetic background (gene-gene interactions), gene-environment interactions, and developmental stochasticity. Finally, we comment on evolutionary alterations to developmental processes, and the evolution of disease buffering mechanisms.
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Affiliation(s)
- Fjodor Merkuri
- Department of Biological Sciences, University of Massachusetts Lowell, Lowell, Massachusetts
| | - Jennifer L Fish
- Department of Biological Sciences, University of Massachusetts Lowell, Lowell, Massachusetts
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16
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Cavodeassi F, Creuzet S, Etchevers HC. The hedgehog pathway and ocular developmental anomalies. Hum Genet 2018; 138:917-936. [PMID: 30073412 PMCID: PMC6710239 DOI: 10.1007/s00439-018-1918-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 07/24/2018] [Indexed: 12/18/2022]
Abstract
Mutations in effectors of the hedgehog signaling pathway are responsible for a wide variety of ocular developmental anomalies. These range from massive malformations of the brain and ocular primordia, not always compatible with postnatal life, to subtle but damaging functional effects on specific eye components. This review will concentrate on the effects and effectors of the major vertebrate hedgehog ligand for eye and brain formation, Sonic hedgehog (SHH), in tissues that constitute the eye directly and also in those tissues that exert indirect influence on eye formation. After a brief overview of human eye development, the many roles of the SHH signaling pathway during both early and later morphogenetic processes in the brain and then eye and periocular primordia will be evoked. Some of the unique molecular biology of this pathway in vertebrates, particularly ciliary signal transduction, will also be broached within this developmental cellular context.
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Affiliation(s)
- Florencia Cavodeassi
- Institute for Medical and Biomedical Education, St. George´s University of London, Cranmer Terrace, London, SW17 0RE, UK
| | - Sophie Creuzet
- Institut des Neurosciences Paris-Saclay (Neuro-PSI), UMR 9197, CNRS, Université Paris-Sud, 1 Avenue de la Terrasse, 91198, Gif-sur-Yvette Cedex, France
| | - Heather C Etchevers
- Aix-Marseille Univ, Marseille Medical Genetics (MMG), INSERM, Faculté de Médecine, 27 boulevard Jean Moulin, 13005, Marseille, France.
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17
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Roessler E, Hu P, Marino J, Hong S, Hart R, Berger S, Martinez A, Abe Y, Kruszka P, Thomas JW, Mullikin JC, Wang Y, Wong WSW, Niederhuber JE, Solomon BD, Richieri-Costa A, Ribeiro-Bicudo LA, Muenke M. Common genetic causes of holoprosencephaly are limited to a small set of evolutionarily conserved driver genes of midline development coordinated by TGF-β, hedgehog, and FGF signaling. Hum Mutat 2018; 39:1416-1427. [PMID: 29992659 DOI: 10.1002/humu.23590] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 06/05/2018] [Accepted: 07/05/2018] [Indexed: 01/01/2023]
Abstract
Here, we applied targeted capture to examine 153 genes representative of all the major vertebrate developmental pathways among 333 probands to rank their relative significance as causes for holoprosencephaly (HPE). We now show that comparisons of variant transmission versus nontransmission among 136 HPE Trios indicates some reported genes now lack confirmation, while novel genes are implicated. Furthermore, we demonstrate that variation of modest intrinsic effect can synergize with these driver mutations as gene modifiers.
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Affiliation(s)
- Erich Roessler
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Ping Hu
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | | | - Sungkook Hong
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Rachel Hart
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Seth Berger
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Ariel Martinez
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Yu Abe
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Paul Kruszka
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - James W Thomas
- NIH Intramural Sequencing Center, NISC, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - James C Mullikin
- NIH Intramural Sequencing Center, NISC, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | -
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Yupeng Wang
- Inova Translational Medicine Institute, Virginia Commonwealth University School of Medicine, Falls Church, Virginia
| | - Wendy S W Wong
- Inova Translational Medicine Institute, Virginia Commonwealth University School of Medicine, Falls Church, Virginia
| | - John E Niederhuber
- Inova Translational Medicine Institute, Virginia Commonwealth University School of Medicine, Falls Church, Virginia
| | - Benjamin D Solomon
- Inova Translational Medicine Institute, Virginia Commonwealth University School of Medicine, Falls Church, Virginia.,Presently the Managing Director, GeneDx, Gaithersburg, Maryland
| | - Antônio Richieri-Costa
- Hospital for the Rehabilitation of Craniofacial Anomalies, São Paulo University, São Paulo, Brazil
| | - L A Ribeiro-Bicudo
- Institute of Bioscience, Department of Genetics, Federal University of Goias, Goias, Brazil
| | - Maximilian Muenke
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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18
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Dubourg C, Kim A, Watrin E, de Tayrac M, Odent S, David V, Dupé V. Recent advances in understanding inheritance of holoprosencephaly. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:258-269. [PMID: 29785796 DOI: 10.1002/ajmg.c.31619] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 04/13/2018] [Accepted: 04/16/2018] [Indexed: 12/16/2022]
Abstract
Holoprosencephaly (HPE) is a complex genetic disorder of the developing forebrain characterized by high phenotypic and genetic heterogeneity. HPE was initially defined as an autosomal dominant disease, but recent research has shown that its mode of transmission is more complex. The past decade has witnessed rapid development of novel genetic technologies and significant progresses in clinical studies of HPE. In this review, we recapitulate genetic epidemiological studies of the largest European HPE cohort and summarize the novel genetic discoveries of HPE based on recently developed diagnostic methods. Our main purpose is to present different inheritance patterns that exist for HPE with a particular emphasis on oligogenic inheritance and its implications in genetic counseling.
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Affiliation(s)
- Christèle Dubourg
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F - 35000, Rennes, France.,Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Artem Kim
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F - 35000, Rennes, France
| | - Erwan Watrin
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F - 35000, Rennes, France
| | - Marie de Tayrac
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F - 35000, Rennes, France.,Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Sylvie Odent
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F - 35000, Rennes, France.,Service de Génétique Clinique, CHU, Rennes, France
| | - Véronique David
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F - 35000, Rennes, France.,Service de Génétique Moléculaire et Génomique, CHU, Rennes, France
| | - Valérie Dupé
- Univ Rennes, CNRS, IGDR (Institut de génétique et développement de Rennes) - UMR 6290, F - 35000, Rennes, France
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19
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Roessler E, Hu P, Muenke M. Holoprosencephaly in the genomics era. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:165-174. [PMID: 29770992 DOI: 10.1002/ajmg.c.31615] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 04/06/2018] [Accepted: 04/11/2018] [Indexed: 01/08/2023]
Abstract
Holoprosencephaly (HPE) is the direct consequence of specific genetic and/or environmental insults interrupting the midline specification of the nascent forebrain. Such disturbances can lead to a broad range of phenotypic consequences for the brain and face in humans. This malformation sequence is remarkably common in utero (1 in 250 human fetuses), but 97% typically do not survive to birth. The precise molecular pathogenesis of HPE in these early human embryos remains largely unknown. Here, we outline our current understanding of the principal driving factors leading to HPE pathologies and elaborate our multifactorial integrated genomics approach. Overall, our understanding of the pathogenesis continues to become simpler, rather than more complicated. Genomic technologies now provide unprecedented insight into disease-associated variation, including the overall extent of genetic interactions (coding and noncoding) predicted to explain divergent phenotypes.
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Affiliation(s)
- Erich Roessler
- Medical Genetics Branch, National Human, Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Ping Hu
- Medical Genetics Branch, National Human, Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Maximilian Muenke
- Medical Genetics Branch, National Human, Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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20
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Martinez AF, Kruszka PS, Muenke M. Extracephalic manifestations of nonchromosomal, nonsyndromic holoprosencephaly. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:246-257. [PMID: 29761634 DOI: 10.1002/ajmg.c.31616] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 03/29/2018] [Accepted: 04/11/2018] [Indexed: 12/13/2022]
Abstract
Nonchromosomal, nonsyndromic holoprosencephaly (NCNS-HPE) has traditionally been considered as a condition of brain and craniofacial maldevelopment. In this review, we present the results of a comprehensive literature search supporting a wide spectrum of extracephalic manifestations identified in patients with NCNS-HPE. These manifestations have been described in case reports and in large cohorts of patients with "single-gene" mutations, suggesting that the NCNS-HPE phenotype can be more complex than traditionally thought. Likely, a complex network of interacting genetic variants and environmental factors is responsible for these systemic abnormalities that deviate from the usual brain and craniofacial findings in NCNS-HPE. In addition to the systemic consequences of pituitary dysfunction (as a direct result of brain midline defects), here we describe a number of extracephalic findings of NCNS-HPE affecting various organ systems. It is our goal to provide a guide of extracephalic features for clinicians given the important clinical implications of these manifestations for the management and care of patients with HPE and their mutation-positive relatives. The health risks associated with some manifestations (e.g., fatty liver disease) may have historically been neglected in affected families.
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Affiliation(s)
- Ariel F Martinez
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Paul S Kruszka
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Maximilian Muenke
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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21
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Hong M, Krauss RS. Modeling the complex etiology of holoprosencephaly in mice. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:140-150. [PMID: 29749693 DOI: 10.1002/ajmg.c.31611] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 03/28/2018] [Accepted: 04/02/2018] [Indexed: 12/14/2022]
Abstract
Holoprosencephaly (HPE) is a common developmental defect caused by failure to define the midline of the forebrain and/or midface. HPE is associated with heterozygous mutations in Nodal and Sonic hedgehog (SHH) pathway components, but clinical presentation is highly variable, and many mutation carriers are unaffected. It is therefore thought that such mutations interact with more common modifiers, genetic and/or environmental, to produce severe patterning defects. Modifiers are difficult to identify, as their effects are context-dependent and occur within the complex genetic and environmental landscapes that characterize human populations. This has made a full understanding of HPE etiology challenging. We discuss here the use of mice, a genetically tractable model sensitive to teratogens, as a system to address this challenge. Mice carrying mutations in human HPE genes often display wide variations in phenotypic penetrance and expressivity when placed on different genetic backgrounds, demonstrating the existence of silent HPE modifier genes. Studies with mouse lines carrying SHH pathway mutations on appropriate genetic backgrounds have led to identification of both genetic and environmental modifiers that synergize with the mutations to produce a spectrum of HPE phenotypes. These models favor a scenario in which multiple modifying influences-both genetic and environmental, sensitizing and protective-interact with bona fide HPE mutations to grade phenotypic outcomes. Despite the complex interplay of HPE risk factors, mouse models have helped establish some clear concepts in HPE etiology. A combination of mouse and human cohort studies should improve our understanding of this fascinating and medically important issue.
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Affiliation(s)
- Mingi Hong
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Robert S Krauss
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York
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