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Malta M, AlMutiri R, Martin CS, Srour M. Holoprosencephaly: Review of Embryology, Clinical Phenotypes, Etiology and Management. CHILDREN 2023; 10:children10040647. [PMID: 37189898 DOI: 10.3390/children10040647] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 02/21/2023] [Accepted: 03/27/2023] [Indexed: 03/31/2023]
Abstract
Holoprosencephaly (HPE) is the most common malformation of the prosencephalon in humans. It is characterized by a continuum of structural brain anomalies resulting from the failure of midline cleavage of the prosencephalon. The three classic subtypes of HPE are alobar, semilobar and lobar, although a few additional categories have been added to this original classification. The severity of the clinical phenotype is broad and usually mirrors the radiologic and associated facial features. The etiology of HPE includes both environmental and genetic factors. Disruption of sonic hedgehog (SHH) signaling is the main pathophysiologic mechanism underlying HPE. Aneuploidies, chromosomal copy number variants and monogenic disorders are identified in a large proportion of HPE patients. Despite the high postnatal mortality and the invariable presence of developmental delay, recent advances in diagnostic methods and improvements in patient management over the years have helped to increase survival rates. In this review, we provide an overview of the current knowledge related to HPE, and discuss the classification, clinical features, genetic and environmental etiologies and management.
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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: 5] [Impact Index Per Article: 2.5] [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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Guo T, Han X, He J, Feng J, Jing J, Janečková E, Lei J, Ho TV, Xu J, Chai Y. KDM6B interacts with TFDP1 to activate P53 signalling in regulating mouse palatogenesis. eLife 2022; 11:74595. [PMID: 35212626 PMCID: PMC9007587 DOI: 10.7554/elife.74595] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2021] [Accepted: 02/24/2022] [Indexed: 11/13/2022] Open
Abstract
Epigenetic regulation plays extensive roles in diseases and development. Disruption of epigenetic regulation not only increases the risk of cancer, but can also cause various developmental defects. However, the question of how epigenetic changes lead to tissue-specific responses during neural crest fate determination and differentiation remains understudied. Using palatogenesis as a model, we reveal the functional significance of Kdm6b, an H3K27me3 demethylase, in regulating mouse embryonic development. Our study shows that Kdm6b plays an essential role in cranial neural crest development, and loss of Kdm6b disturbs P53 pathway-mediated activity, leading to complete cleft palate along with cell proliferation and differentiation defects in mice. Furthermore, activity of H3K27me3 on the promoter of Trp53 is antagonistically controlled by Kdm6b, and Ezh2 in cranial neural crest cells. More importantly, without Kdm6b, the transcription factor TFDP1, which normally binds to the promoter of Trp53, cannot activate Trp53 expression in palatal mesenchymal cells. Furthermore, the function of Kdm6b in activating Trp53 in these cells cannot be compensated for by the closely related histone demethylase Kdm6a. Collectively, our results highlight the important role of the epigenetic regulator KDM6B and how it specifically interacts with TFDP1 to achieve its functional specificity in regulating Trp53 expression, and further provide mechanistic insights into the epigenetic regulatory network during organogenesis.
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Affiliation(s)
- Tingwei Guo
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Xia Han
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Jinzhi He
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Jifan Feng
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Junjun Jing
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Eva Janečková
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Jie Lei
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Thach-Vu Ho
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Jian Xu
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
| | - Yang Chai
- Center for Craniofacial Molecular Biology, University of Southern California, Los Angeles, United States
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4
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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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5
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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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6
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Lo HF, Hong M, Szutorisz H, Hurd YL, Krauss RS. Δ9-Tetrahydrocannabinol inhibits Hedgehog-dependent patterning during development. Development 2021; 148:272342. [PMID: 34610637 DOI: 10.1242/dev.199585] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 08/23/2021] [Indexed: 12/20/2022]
Abstract
Many developmental disorders are thought to arise from an interaction between genetic and environmental risk factors. The Hedgehog (HH) signaling pathway regulates myriad developmental processes, and pathway inhibition is associated with birth defects, including holoprosencephaly (HPE). Cannabinoids are HH pathway inhibitors, but little is known of their effects on HH-dependent processes in mammalian embryos, and their mechanism of action is unclear. We report that the psychoactive cannabinoid Δ9-tetrahydrocannabinol (THC) induces two hallmark HH loss-of-function phenotypes (HPE and ventral neural tube patterning defects) in Cdon mutant mice, which have a subthreshold deficit in HH signaling. THC therefore acts as a 'conditional teratogen', dependent on a complementary but insufficient genetic insult. In vitro findings indicate that THC is a direct inhibitor of the essential HH signal transducer smoothened. The canonical THC receptor, cannabinoid receptor-type 1, is not required for THC to inhibit HH signaling. Cannabis consumption during pregnancy may contribute to a combination of risk factors underlying specific developmental disorders. These findings therefore have significant public health relevance.
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Affiliation(s)
- Hsiao-Fan Lo
- Department of Cell, Developmental, and Regenerative Biology, New York, NY 10029, USA
| | - Mingi Hong
- Department of Cell, Developmental, and Regenerative Biology, New York, NY 10029, USA
| | - Henrietta Szutorisz
- Addiction Institute and Departments of Psychiatry and Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Yasmin L Hurd
- Addiction Institute and Departments of Psychiatry and Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Robert S Krauss
- Department of Cell, Developmental, and Regenerative Biology, New York, NY 10029, USA
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7
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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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8
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Obara-Moszyńska M, Budny B, Kałużna M, Zawadzka K, Jamsheer A, Rohde A, Ruchała M, Ziemnicka K, Niedziela M. CDON gene contributes to pituitary stalk interruption syndrome associated with unilateral facial and abducens nerve palsy. J Appl Genet 2021; 62:621-629. [PMID: 34235642 PMCID: PMC8571149 DOI: 10.1007/s13353-021-00649-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 06/21/2021] [Accepted: 06/28/2021] [Indexed: 11/06/2022]
Abstract
The relationship between congenital defects of the brain and facial anomalies was proven. The Hedgehog signaling pathway plays a fundamental role in normal craniofacial development in humans. Mutations in the sonic hedgehog (SHH) signaling gene CDON have been recently reported in patients with holoprosencephaly and with pituitary stalk interruption syndrome (PSIS). This study’s aim was an elucidation of an 18-year-old patient presenting PSIS, multiple pituitary hormone deficiency, and congenital unilateral facial and abducens nerve palsy. Additionally, bilateral sensorineural hearing loss, dominating at the right site, was diagnosed. From the second year of life, growth deceleration was observed, and from the age of eight, anterior pituitary hormone deficiencies were gradually confirmed and substituted. At the MRI, characteristic triad for PSIS (anterior pituitary hypoplasia, interrupted pituitary stalk and ectopic posterior lobe) was diagnosed. We performed a comprehensive genomic screening, including microarrays for structural rearrangements and whole-exome sequencing for a monogenic defect. A novel heterozygous missense variant in the CDON gene (c.1814G > T; p.Gly605Val) was identified. The variant was inherited from the mother, who, besides short stature, did not show any disease symptoms. The variant was absent in control databases and 100 healthy subjects originating from the same population. We report a novel variant in the CDON gene associated with PSIS and congenital cranial nerve palsy. The variant revealed autosomal dominant inheritance with incomplete penetrance in concordance with previous studies reporting CDON defects.
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Affiliation(s)
- Monika Obara-Moszyńska
- Department of Pediatric Endocrinology and Rheumatology, Poznan University of Medical Sciences, 27/33 Szpitalna Str, 60-572, Poznan, Poland.
| | - Bartłomiej Budny
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 49 Przybyszewskiego Str., 60-355, Poznan, Poland
| | - Małgorzata Kałużna
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 49 Przybyszewskiego Str., 60-355, Poznan, Poland
| | - Katarzyna Zawadzka
- MNM Diagnostics Sp. z o.o., 64 Macieja Rataja Str., 61-695, Poznan, Poland
| | - Aleksander Jamsheer
- Department of Medical Genetics, Poznan University of Medical Sciences, 8 Rokietnicka Str, 60-806, Poznan, Poland
| | - Anna Rohde
- Department of Pediatric Endocrinology and Rheumatology, Poznan University of Medical Sciences, 27/33 Szpitalna Str, 60-572, Poznan, Poland
| | - Marek Ruchała
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 49 Przybyszewskiego Str., 60-355, Poznan, Poland
| | - Katarzyna Ziemnicka
- Department of Endocrinology, Metabolism and Internal Medicine, Poznan University of Medical Sciences, 49 Przybyszewskiego Str., 60-355, Poznan, Poland
| | - Marek Niedziela
- Department of Pediatric Endocrinology and Rheumatology, Poznan University of Medical Sciences, 27/33 Szpitalna Str, 60-572, Poznan, Poland
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9
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Riddle A, Nagaraj U, Hopkin RJ, Kline-Fath B, Venkatesan C. Fetal Magnetic Resonance Imaging (MRI) in Holoprosencephaly and Associations With Clinical Outcome: Implications for Fetal Counseling. J Child Neurol 2021; 36:357-364. [PMID: 33226281 DOI: 10.1177/0883073820972290] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Holoprosencephaly is the most common malformation of forebrain development and includes a wide spectrum of severity. The objective of this retrospective study was to evaluate fetal magnetic resonance imaging (MRI) associations with outcome. Of the 63 cases identified on antenatal ultrasonography, 28 cases were confirmed on fetal MRI. There were 17 live births; 9 patients died within the first month of life. There were 7 survivors. The vast majority were nonambulatory and required feeding support; none required respiratory support. We found that presence and number of non-holoprosencephaly-associated malformations was also associated with survival. Of 5 patients with 3 or more systemic anomalies, 4 died regardless of holoprosencephaly subtype and 1 was lost to follow-up. Patients with suspected holoprosencephaly on ultrasonography should have full body fetal MRI and echocardiogram to better evaluate systemic anomalies. Counseling should involve pediatric palliative care services to prepare families in caring for babies with limited life span.
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Affiliation(s)
- Artur Riddle
- Division of Neurology, 2518Cincinnati Children's Hospital, Cincinnati, OH, USA.,Division of Human Genetics, 2518Cincinnati Children's Hospital, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.,Division of Pediatric Neurology, 6684Oregon Health & Science University, Portland, OR, USA
| | - Usha Nagaraj
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.,Division of Radiology and Medical Imaging, Cincinnati Children's Hospital, Cincinnati, OH, USA
| | - Robert J Hopkin
- Division of Human Genetics, 2518Cincinnati Children's Hospital, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Beth Kline-Fath
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA.,Division of Radiology and Medical Imaging, Cincinnati Children's Hospital, Cincinnati, OH, USA
| | - Charu Venkatesan
- Division of Neurology, 2518Cincinnati Children's Hospital, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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10
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Abstract
Pituitary stalk interruption syndrome (PSIS) is a distinct developmental defect of the pituitary gland identified by magnetic resonance imaging and characterized by a thin, interrupted, attenuated or absent pituitary stalk, hypoplasia or aplasia of the adenohypophysis, and an ectopic posterior pituitary. The precise etiology of PSIS still remains elusive or incompletely confirmed in most cases. Adverse perinatal events, including breech delivery and hypoxia, were initially proposed as the underlying mechanism affecting the hypothalamic-pituitary axis. Nevertheless, recent findings have uncovered a wide variety of PSIS-associated molecular defects in genes involved in pituitary development, holoprosencephaly (HPE), neural development, and other important cellular processes such as cilia function. The application of whole exome sequencing (WES) in relatively large cohorts has identified an expanded pool of potential candidate genes, mostly related to the Wnt, Notch, and sonic hedgehog signaling pathways that regulate pituitary growth and development during embryogenesis. Importantly, WES has revealed coexisting pathogenic variants in a significant number of patients; therefore, pointing to a multigenic origin and inheritance pattern of PSIS. The disorder is characterized by inter- and intrafamilial variability and incomplete or variable penetrance. Overall, PSIS is currently viewed as a mild form of an expanded HPE spectrum. The wide and complex clinical manifestations include evolving pituitary hormone deficiencies (with variable timing of onset and progression) and extrapituitary malformations. Severe and life-threatening symptomatology is observed in a subset of patients with complete pituitary hormone deficiency during the neonatal period. Nevertheless, most patients are referred later in childhood for growth retardation. Prompt and appropriate hormone substitution therapy constitutes the cornerstone of treatment. Further studies are needed to uncover the etiopathogenesis of PSIS.
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Affiliation(s)
- Antonis Voutetakis
- Department of Pediatrics, School of Medicine, Democritus University of Thrace, Alexandroupolis, Thrace, Greece.
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11
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Hong M, Christ A, Christa A, Willnow TE, Krauss RS. Cdon mutation and fetal alcohol converge on Nodal signaling in a mouse model of holoprosencephaly. eLife 2020; 9:60351. [PMID: 32876567 PMCID: PMC7467722 DOI: 10.7554/elife.60351] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 08/10/2020] [Indexed: 02/07/2023] Open
Abstract
Holoprosencephaly (HPE), a defect in midline patterning of the forebrain and midface, arises ~1 in 250 conceptions. It is associated with predisposing mutations in the Nodal and Hedgehog (HH) pathways, with penetrance and expressivity graded by genetic and environmental modifiers, via poorly understood mechanisms. CDON is a multifunctional co-receptor, including for the HH pathway. In mice, Cdon mutation synergizes with fetal alcohol exposure, producing HPE phenotypes closely resembling those seen in humans. We report here that, unexpectedly, Nodal signaling is a major point of synergistic interaction between Cdon mutation and fetal alcohol. Window-of-sensitivity, genetic, and in vitro findings are consistent with a model whereby brief exposure of Cdon mutant embryos to ethanol during gastrulation transiently and partially inhibits Nodal pathway activity, with consequent effects on midline patterning. These results illuminate mechanisms of gene-environment interaction in a multifactorial model of a common birth defect.
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Affiliation(s)
- Mingi Hong
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, United States
| | - Annabel Christ
- Max-Delbruck-Center for Molecular Medicine, Berlin, Germany
| | - Anna Christa
- Max-Delbruck-Center for Molecular Medicine, Berlin, Germany
| | | | - Robert S Krauss
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, United States
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12
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Gounongbé C, Marangoni M, Gouder de Beauregard V, Delaunoy M, Jissendi P, Cassart M, Désir J. Middle interhemispheric variant of holoprosencephaly: First prenatal report of a ZIC2 missense mutation. Clin Case Rep 2020; 8:1287-1292. [PMID: 32695376 PMCID: PMC7364085 DOI: 10.1002/ccr3.2896] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Accepted: 01/24/2020] [Indexed: 12/22/2022] Open
Abstract
We present a case of a middle interhemispheric variant of antenatal discovery associated with a de novo missense variant (NM_007129.5: c.1109G>A p.(Cys370Tyr)) in the ZIC2 gene. Our case represents the first prenatal description of a ZIC2 missense mutation found in association with syntelencephaly.
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Affiliation(s)
| | - Martina Marangoni
- Center of Human GeneticsHôpital ErasmeUniversité Libre de BruxellesBrusselsBelgium
| | | | - Mélanie Delaunoy
- Center of Human GeneticsHôpital ErasmeUniversité Libre de BruxellesBrusselsBelgium
| | - Patrice Jissendi
- Department of RadiologyHôpitaux Iris Sud and CHU Saint‐PierreBrusselsBelgium
| | - Marie Cassart
- Department of Fetal MedicineCHU Saint‐PierreBrusselsBelgium
- Department of RadiologyHôpitaux Iris Sud and CHU Saint‐PierreBrusselsBelgium
| | - Julie Désir
- Center of Human GeneticsHôpital ErasmeUniversité Libre de BruxellesBrusselsBelgium
- Department of RadiologyHôpitaux Iris Sud and CHU Saint‐PierreBrusselsBelgium
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13
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Weiss K, Kruszka PS, Levey E, Muenke M. Holoprosencephaly from conception to adulthood. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2019; 178:122-127. [PMID: 30182446 DOI: 10.1002/ajmg.c.31624] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 04/11/2018] [Indexed: 01/15/2023]
Abstract
Holoprosencephaly (HPE) consists of a spectrum of malformations related to incomplete separation of the prosencephalon. There is a wide clinical variability depending on the HPE subtype seen on imaging. Early postnatal lethality is common, however a significant fraction of newborns diagnosed with HPE will survive into childhood and even adulthood. Here we will review the clinical management of HPE during different ages from the prenatal period to adulthood.
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Affiliation(s)
- Karin Weiss
- Genetics Institute, Rambam Health Care Campus, Haifa, Israel
| | - Paul S Kruszka
- National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Eric Levey
- Health Services for Children with Special Needs, Inc., Washington, DC
| | - Max Muenke
- National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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14
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Honey EM, Bütow KW, Zwahlen RA. Holoprosencephaly with Clefts: Data of 85 Patients, Treatment and Outcome: Part 1: History, Subdivisions, and Data on 85 Holoprosencephalic Cleft Patients. Ann Maxillofac Surg 2019; 9:140-145. [PMID: 31293943 PMCID: PMC6585219 DOI: 10.4103/ams.ams_50_19] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
CONTEXT Cleft patients with Holoprosencephaly (HPE) constitute a controversy due to a variable facial appearance. HPE appearance varies from only a columella to a prolabium-premaxilla complex agenesis up to a common unilateral or bilateral cleft lip and palate with a single central incisor, various brain deformities, and/or even normal brain development. It is challenging to designate such various appearances, to understand their etiopathogenesis, and to choose the most appropriate management. Literature was reviewed for diagnostic criteria, pregnancy history, clinical findings, brain development, survival rate, initial perioperative management, and postsurgical midfacial growth in cleft patients with HPE. The findings were compared with a clinical database of 85 cleft patients with HPE at the Department of Maxillofacial and Oral Surgery, University of Pretoria. AIMS OF PART 1 The aim of the study is to overcome disparities widely existing among clinicians regarding definitive diagnostic criteria, especially in cases with a common appearance of a uni- or bilateral cleft lip alveolus or cleft lip, alveolus and palate deformity, and cases presenting facial structural agenesis. MATERIALS AND METHODS A literature search related to diagnostic criteria was compared to results of a cleft HPE database from a single tertiary institution. RESULTS HPE cleft cases can be allocated to one of the following subdivisions: (1) columella complex agenesis (Ag-Colum), (2) prolabium-premaxilla-columella complex agenesis in cleft lip-alveolus deformities (Ag-CLA), (3) prolabium-premaxilla-columella agenesis in cases with complete cleft lip alveolus palate (Ag-CLAP), and (4) standard type (holoprosencephaly in patients with a standard cleft) with uni- or bilateral CLA or CLAP, hard and soft palate cleft (hPsP), and atrophic premaxillae, with or without single central incisor. Further, incidence, variation in brain development, and appearances in HPE cleft patients of different races and gender, epilepsy, and early death are discussed. Conclusion: This paper adds new data and facts to the existing literature related to cleft lip and palate patients suffering from HPE.
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Affiliation(s)
- Engela M. Honey
- Facial Cleft Deformity Clinic, Department of Maxillo-Facial and Oral Surgery, University of Pretoria, Pretoria, South Africa
- Department of Biochemistry, Genetics and Microbiology, Faculty of Natural and Agricultural Science, University of Pretoria, Pretoria, South Africa
| | - Kurt W. Bütow
- Facial Cleft Deformity Clinic, Department of Maxillo-Facial and Oral Surgery, University of Pretoria, Pretoria, South Africa
- Suite A2 Maxillo-Facial Surgery, The Life Wilgers Hospital, Pretoria, South Africa
| | - Roger Arthur Zwahlen
- Private Practice in Oral and Maxillofacial Surgery, Grand-Places 16, Fribourg, Switzerland
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Abstract
Disorders of the developing nervous system may be of genetic origin, comprising congenital malformations of spine and brain as well as metabolic or vascular disorders that affect normal brain development. Acquired causes include congenital infections, hypoxic-ischemic or traumatic brain injury, and a number of rare neoplasms. This chapter focuses on the clinical presentation and workup of neurogenetic disorders presenting in the fetal or neonatal period. After a summary of the most frequent clinical presentations, clues from history taking and clinical examination are illustrated with short case reports. This is followed by a discussion of the different tools available for the workup of neurogenetic disorders, including the various genetic techniques with their advantages and disadvantages. The implications of a molecular genetic diagnosis for the patient and family are addressed in the section on counseling. The chapter concludes with a proposed workflow that may help the clinician when confronted with a potential neurogenetic disorder in the fetal or neonatal period.
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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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17
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Solomon BD, Retterer K, Juusola J. Holoprosencephaly: A clinical genomics perspective. AMERICAN JOURNAL OF MEDICAL GENETICS. PART C, SEMINARS IN MEDICAL GENETICS 2018; 178:194-197. [PMID: 29749690 DOI: 10.1002/ajmg.c.31613] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 04/03/2018] [Accepted: 04/04/2018] [Indexed: 12/17/2023]
Abstract
New and rapidly evolving technologies have dramatically impacted the practice of clinical genetics as well as broader areas of medicine. To illustrate this trend from the perspective of a clinical molecular laboratory, we briefly summarize our general experience conducting exome testing for patients with holoprosencephaly (HPE). Though these cases are not representative of HPE more generally (i.e., cases undergoing exome sequencing represent a skewed sample), results include a 22% positive rate from exome testing. Of interest, 29% of reported results involved genes not considered to be classic HPE genes, indicating more evidence that HPE may fall within the severe spectrum of many other genetic conditions.
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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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Kousa YA, du Plessis AJ, Vezina G. Prenatal diagnosis of holoprosencephaly. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:206-213. [PMID: 29770996 DOI: 10.1002/ajmg.c.31618] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 04/12/2018] [Accepted: 04/16/2018] [Indexed: 11/09/2022]
Abstract
Holoprosencephaly is a spectrum of congenital defects of forebrain development characterized by incomplete separation of the cerebral hemispheres. In vivo diagnosis can be established with prenatal brain imaging and disease severity correlates with extent of abnormally developed brain tissue. Advances in magnetic resonance imaging (MRI) over the past 25 years and their application to the fetus have enabled diagnosis of holoprosencephaly in utero. Here, we report on the prenatal diagnosis of holoprosencephaly using MRI as part of a diagnostic and management evaluation at a tertiary and quaternary referral center. Using an advanced MRI protocol and a 1.5-Tesla magnet, we show radiographic data diagnostic for the holoprosencephaly spectrum, including alobar, semilobar, lobar, middle interhemispheric, and septopreoptic variant. Accurate prenatal evaluation is important because the severity of imaging findings correlates with postnatal morbidity and mortality in holoprosencephaly. Therefore, this work has implications for the evaluation, diagnosis, management, and genetic counseling that families can receive during a pregnancy.
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Affiliation(s)
- Youssef A Kousa
- Division of Neurology, Children's National Health System, Washington, DC
| | - Adré J du Plessis
- Division of Fetal and Transitional Medicine, Children's National Health System, Washington, DC
| | - Gilbert Vezina
- Division of Radiology, Children's National Health System, Washington, DC
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21
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Wotton D, Taniguchi K. Functions of TGIF homeodomain proteins and their roles in normal brain development and holoprosencephaly. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2018; 178:128-139. [PMID: 29749689 DOI: 10.1002/ajmg.c.31612] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 03/30/2018] [Accepted: 04/02/2018] [Indexed: 01/08/2023]
Abstract
Holoprosencephaly (HPE) is a frequent human forebrain developmental disorder with both genetic and environmental causes. Multiple loci have been associated with HPE in humans, and potential causative genes at 14 of these loci have been identified. Although TGIF1 (originally TGIF, for Thymine Guanine-Interacting Factor) is among the most frequently screened genes in HPE patients, an understanding of how mutations in this gene contribute to the pathogenesis of HPE has remained elusive. However, mouse models based on loss of function of Tgif1, and the related Tgif2 gene, have shed some light on how human TGIF1 variants might cause HPE. Functional analyses of TGIF proteins and of TGIF1 single nucleotide variants from HPE patients, combined with analysis of forebrain development in mouse embryos lacking both Tgif1 and Tgif2, suggest that TGIFs regulate the transforming growth factor ß/Nodal signaling pathway and sonic hedgehog (SHH) signaling independently. Although, some developmental processes that are regulated by TGIFs may be Nodal-dependent, it appears that the forebrain patterning defects and HPE in Tgif mutant mouse embryos is primarily due to altered signaling via the Shh pathway.
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Affiliation(s)
- David Wotton
- Department of Biochemistry and Molecular Genetics, Center for Cell Signaling, University of Virginia, Charlottesville, Virginia
| | - Kenichiro Taniguchi
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, Michigan
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22
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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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23
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Link between the causative genes of holoprosencephaly: Zic2 directly regulates Tgif1 expression. Sci Rep 2018; 8:2140. [PMID: 29391420 PMCID: PMC5794963 DOI: 10.1038/s41598-018-20242-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Accepted: 01/15/2018] [Indexed: 02/07/2023] Open
Abstract
One of the causal genes for holoprosencephaly (HPE) is ZIC2 (HPE5). It belongs to the zinc finger protein of the cerebellum (Zic) family of genes that share a C2H2-type zinc finger domain, similar to the GLI family of genes. In order to clarify the role of Zic2 in gene regulation, we searched for its direct target genes using chromatin immunoprecipitation (ChIP). We identified TGIF1 (HPE4), another holoprosencephaly-causative gene in humans. We identified Zic2-binding sites (ZBS) on the 5′ flanking region of Tgif1 by in vitro DNA binding assays. ZBS were essential for Zic2-dependent transcriptional activation in reporter gene assays. Zic2 showed a higher affinity to ZBS than GLI-binding sequences. Zic2-binding to the cis-regulatory element near the Tgif1 promoter may be involved in the mechanism underlying forebrain development and incidences of HPE.
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24
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Abstract
The ZIC2 transcription factor is one of the most commonly mutated genes in Holoprosencephaly (HPE) probands. HPE is a severe congenital defect of forebrain development which occurs when the cerebral hemispheres fail to separate during the early stages of organogenesis and is typically associated with mispatterning of the embryonic midline. Recent study of genotype-phenotype correlations in HPE cases has defined distinctive features of ZIC2-associated HPE presentation and genetics, revealing that ZIC2 mutation does not produce the craniofacial abnormalities generally thought to characterise HPE but leads to a range of non-forebrain phenotypes. Furthermore, the studies confirm the extent of ZIC2 allelic heterogeneity and that pathogenic variants of ZIC2 are associated with both classic and middle interhemispheric variant (MIHV) HPE which arise from defective ventral and dorsal forebrain patterning, respectively. An allelic series of mouse mutants has helped to delineate the cellular and molecular mechanisms by which one gene leads to defects in these related but distinct embryological processes.
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Affiliation(s)
- Kristen S Barratt
- Early Mammalian Development Laboratory, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Ruth M Arkell
- Early Mammalian Development Laboratory, John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.
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25
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Hong M, Srivastava K, Kim S, Allen BL, Leahy DJ, Hu P, Roessler E, Krauss RS, Muenke M. BOC is a modifier gene in holoprosencephaly. Hum Mutat 2017; 38:1464-1470. [PMID: 28677295 DOI: 10.1002/humu.23286] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 06/20/2017] [Accepted: 06/28/2017] [Indexed: 12/18/2022]
Abstract
Holoprosencephaly (HPE), a common developmental defect of the forebrain and midface, has a complex etiology. Heterozygous, loss-of-function mutations in the sonic hedgehog (SHH) pathway are associated with HPE. However, mutation carriers display highly variable clinical presentation, leading to an "autosomal dominant with modifier" model, in which the penetrance and expressivity of a predisposing mutation is graded by genetic or environmental modifiers. Such modifiers have not been identified. Boc encodes a SHH coreceptor and is a silent HPE modifier gene in mice. Here, we report the identification of missense BOC variants in HPE patients. Consistent with these alleles functioning as HPE modifiers, individual variant BOC proteins had either loss- or gain-of-function properties in cell-based SHH signaling assays. Therefore, in addition to heterozygous loss-of-function mutations in specific SHH pathway genes and an ill-defined environmental component, our findings identify a third variable in HPE: low-frequency modifier genes, BOC being the first identified.
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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
| | - Kshitij Srivastava
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Sungjin Kim
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Benjamin L Allen
- Department of Cell and Developmental Biology, University of Michigan, Ann Arbor, Michigan
| | - Daniel J Leahy
- Department of Molecular Biosciences, University of Texas at Austin, Austin, Texas
| | - Ping Hu
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Erich Roessler
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Robert S Krauss
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York
| | - Maximilian Muenke
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
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26
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Weiss K, Kruszka P, Guillen Sacoto MJ, Addissie YA, Hadley DW, Hadsall CK, Stokes B, Hu P, Roessler E, Solomon B, Wiggs E, Thurm A, Hufnagel RB, Zein WM, Hahn JS, Stashinko E, Levey E, Baldwin D, Clegg NJ, Delgado MR, Muenke M. In-depth investigations of adolescents and adults with holoprosencephaly identify unique characteristics. Genet Med 2017. [PMID: 28640243 PMCID: PMC5763157 DOI: 10.1038/gim.2017.68] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Purpose With improved medical care, some individuals with holoprosencephaly (HPE) are surviving into adulthood. We investigated the clinical manifestations of adolescents and adults with HPE and explored the underlying molecular causes. Methods Participants included 20 subjects 15 years of age and older. Clinical assessments included dysmorphology exams, cognitive testing, swallowing studies, ophthalmic examination, and brain magnetic resonance imaging. Genetic testing included chromosomal microarray, Sanger sequencing for SHH, ZIC2, SIX3, and TGIF, and whole-exome sequencing (WES) of 10 trios. Results Semilobar HPE was the most common subtype of HPE, seen in 50% of the participants. Neurodevelopmental disabilities were found to correlate with HPE subtype. Factors associated with long-term survival included HPE subtype not alobar, female gender, and nontypical facial features. Four participants had de novo pathogenic variants in ZIC2. WES analysis of 11 participants did not reveal plausible candidate genes, suggesting complex inheritance in these cases. Indeed, in two probands there was a history of uncontrolled maternal type 1 diabetes. Conclusion Individuals with various HPE subtypes can survive into adulthood and the neurodevelopmental outcomes are variable. Based on the facial characteristics and molecular evaluations, we suggest that classic genetic causes of HPE may play a smaller role in this cohort.
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Affiliation(s)
- Karin Weiss
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Paul Kruszka
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Maria J Guillen Sacoto
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Yonit A Addissie
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Donald W Hadley
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Casey K Hadsall
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Bethany Stokes
- 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
| | - Erich Roessler
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Beth Solomon
- Speech and Language Pathology Section, Department of Rehabilitation Medicine, Clinical Center, National Institutes of Health, Bethesda, Maryland, USA
| | - Edythe Wiggs
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, USA
| | - Audrey Thurm
- Pediatrics and Developmental Neuroscience Branch, National Institute of Mental Health, Bethesda, Maryland, USA
| | - Robert B Hufnagel
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Wadih M Zein
- Ophthalmic Genetics and Visual Function Branch, National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Jin S Hahn
- Stanford University School of Medicine and Lucile Packard Children's Hospital, Stanford, California, USA
| | - Elaine Stashinko
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Eric Levey
- Neurology and Developmental Medicine, Kennedy Krieger Institute, Baltimore, Maryland, USA
| | - Debbie Baldwin
- Department of Neurology, Texas Scottish Rite Hospital for Children, Dallas, Texas, USA
| | - Nancy J Clegg
- Department of Neurology, Texas Scottish Rite Hospital for Children, Dallas, Texas, USA
| | - Mauricio R Delgado
- Department of Neurology, Texas Scottish Rite Hospital for Children, Dallas, Texas, USA.,Neurology and Neurotherapeutics, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA
| | - Maximilian Muenke
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland, USA
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Hong M, Krauss RS. Ethanol itself is a holoprosencephaly-inducing teratogen. PLoS One 2017; 12:e0176440. [PMID: 28441416 PMCID: PMC5404885 DOI: 10.1371/journal.pone.0176440] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 04/10/2017] [Indexed: 02/05/2023] Open
Abstract
Ethanol is a teratogen, inducing a variety of structural defects in developing humans and animals that are exposed in utero. Mechanisms of ethanol teratogenicity in specific defects are not well understood. Oxidative metabolism of ethanol by alcohol dehydrogenase or cytochrome P450 2E1 has been implicated in some of ethanol's teratogenic effects, either via production of acetaldehyde or competitive inhibition of retinoic acid synthesis. Generalized oxidative stress in response to ethanol may also play a role in its teratogenicity. Among the developmental defects that ethanol has been implicated in is holoprosencephaly, a failure to define the midline of the forebrain and midface that is associated with a deficiency in Sonic hedgehog pathway function. Etiologically, holoprosencephaly is thought to arise from a complex combination of genetic and environmental factors. We have developed a gene-environment interaction model of holoprosencephaly in mice, in which mutation of the Sonic hedgehog coreceptor, Cdon, synergizes with transient in utero exposure to ethanol. This system was used to address whether oxidative metabolism is required for ethanol's teratogenic activity in holoprosencephaly. We report here that t-butyl alcohol, which is neither a substrate nor an inhibitor of alcohol dehydrogenases or Cyp2E1, is a potent inducer of holoprosencephaly in Cdon mutant mice. Additionally, antioxidant treatment did not prevent ethanol- or t-butyl alcohol-induced HPE in these mice. These findings are consistent with the conclusion that ethanol itself, rather than a consequence of its metabolism, is a holoprosencephaly-inducing teratogen.
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Affiliation(s)
- Mingi Hong
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America
| | - Robert S. Krauss
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY, United States of America
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Dubourg C, Carré W, Hamdi-Rozé H, Mouden C, Roume J, Abdelmajid B, Amram D, Baumann C, Chassaing N, Coubes C, Faivre-Olivier L, Ginglinger E, Gonzales M, Levy-Mozziconacci A, Lynch SA, Naudion S, Pasquier L, Poidvin A, Prieur F, Sarda P, Toutain A, Dupé V, Akloul L, Odent S, de Tayrac M, David V. Mutational Spectrum in Holoprosencephaly Shows That FGF is a New Major Signaling Pathway. Hum Mutat 2016; 37:1329-1339. [DOI: 10.1002/humu.23038] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Accepted: 06/22/2016] [Indexed: 12/31/2022]
Affiliation(s)
- Christèle Dubourg
- Service de Génétique Moléculaire et Génomique; CHU; Rennes France
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
| | - Wilfrid Carré
- Service de Génétique Moléculaire et Génomique; CHU; Rennes France
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
| | - Houda Hamdi-Rozé
- Service de Génétique Moléculaire et Génomique; CHU; Rennes France
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
| | - Charlotte Mouden
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
| | - Joëlle Roume
- Service de Génétique Médicale; CHI; Poissy France
| | | | - Daniel Amram
- Unité de Génétique Clinique; CHI; Créteil France
| | | | | | | | | | | | - Marie Gonzales
- Service de Génétique et Embryologie Médicales; Hôpital Armand Trousseau; Paris France
| | | | - Sally-Ann Lynch
- Medical Genetics; Our Lady's Children Hospital; Dublin Ireland
| | | | | | - Amélie Poidvin
- Service d'Endocrinologie; CHU Robert Debré; Paris France
| | | | - Pierre Sarda
- Département de Génétique Médicale; CHU; Montpellier France
| | | | - Valérie Dupé
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
| | - Linda Akloul
- Service de Génétique Clinique; CHU; Rennes France
| | - Sylvie Odent
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
- Service de Génétique Clinique; CHU; Rennes France
| | - Marie de Tayrac
- Service de Génétique Moléculaire et Génomique; CHU; Rennes France
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
| | - Véronique David
- Service de Génétique Moléculaire et Génomique; CHU; Rennes France
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
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29
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Mouden C, Dubourg C, Carré W, Rose S, Quelin C, Akloul L, Hamdi-Rozé H, Viot G, Salhi H, Darnault P, Odent S, Dupé V, David V. Complex mode of inheritance in holoprosencephaly revealed by whole exome sequencing. Clin Genet 2016; 89:659-68. [DOI: 10.1111/cge.12722] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 12/28/2015] [Accepted: 12/30/2015] [Indexed: 12/12/2022]
Affiliation(s)
- C. Mouden
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
| | - C. Dubourg
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
- Laboratoire de Génétique Moléculaire et Génomique; C.H.U. de Rennes; Rennes France
| | - W. Carré
- Laboratoire de Génétique Moléculaire et Génomique; C.H.U. de Rennes; Rennes France
| | - S. Rose
- UMR1085 Institut de Recherche sur la Santé, l'Environnement et le Travail; Université de Rennes 1; Rennes France
| | - C. Quelin
- Service de Génétique Clinique; C.H.U. de Rennes; Rennes France
| | - L. Akloul
- Service de Génétique Clinique; C.H.U. de Rennes; Rennes France
| | - H. Hamdi-Rozé
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
- Laboratoire de Génétique Moléculaire et Génomique; C.H.U. de Rennes; Rennes France
| | - G. Viot
- Service de Génétique Médicale; Maternité Port Royal; Paris France
| | - H. Salhi
- Foetopathologie et Anatomie Pathologique Pédiatrique; Hôpital Cochin; Paris France
| | - P. Darnault
- Service de Radiologie et Imagerie Médicale; C.H.U. de Rennes; Rennes France
| | - S. Odent
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
- Service de Génétique Clinique; C.H.U. de Rennes; Rennes France
| | - V. Dupé
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
| | - V. David
- UMR6290 Institut de Génétique et Développement de Rennes; Université de Rennes 1; Rennes France
- Laboratoire de Génétique Moléculaire et Génomique; C.H.U. de Rennes; Rennes France
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Abstract
It is thought that most structural birth defects are caused by a complex combination of genetic and environmental factors that interact to interfere with morphogenetic processes. It is important not only to identify individual genetic and environmental risk factors for particular defects but also to identify which environmental factors interact specifically with which genetic variants that predispose to the same defect. Genomic and epidemiological studies are critical to this end. Development and analysis of model systems will also be essential for this goal, as well as for understanding the mechanisms that underlie specific gene-environment interactions.
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31
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Hayashi Y, Suzumori N, Sugiura T, Sugiura-Ogasawara M. Prenatal findings of holoprosencephaly. Congenit Anom (Kyoto) 2015; 55:161-3. [PMID: 25620469 DOI: 10.1111/cga.12103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/16/2015] [Indexed: 11/28/2022]
Abstract
Holoprosencephaly (HPE) is a rare brain abnormality characterized by an incomplete cleavage of the primitive prosencephalon of forebrain during early embryogenesis. To determine the clinical characteristics and outcome of fetuses with HPE, we retrospectively analyzed nine patients who were prenatally diagnosed as fetal HPE by ultrasounds. The mean diagnostic weeks were 20 weeks of gestation. Two cases died within one day after birth. The chromosomal examinations were performed in seven cases (trisomy 18: n = 2; trisomy 13: n = 2; 45,XX,der(18)t(18;21)(p10;p10)mat: n = 1; normal karyotype: n = 2). In our HPE cases, most cases had serious facial anomalies and poor prognosis. Our data suggested that the early prenatal diagnosis of HPE allowed time for parental counseling and delivery planning.
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Affiliation(s)
- Yuko Hayashi
- Department of Obstetrics and Gynecology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Division of Clinical and Molecular Genetics, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Department of Obstetrics and Gynecology, Nagoya East Medical Center, Nagoya, Japan
| | - Nobuhiro Suzumori
- Department of Obstetrics and Gynecology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Division of Clinical and Molecular Genetics, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Tokio Sugiura
- Department of Pediatrics and Neonatology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
| | - Mayumi Sugiura-Ogasawara
- Department of Obstetrics and Gynecology, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.,Division of Clinical and Molecular Genetics, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan
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Savastano CP, El-Jaick KB, Costa-Lima MA, Abath CMB, Bianca S, Cavalcanti DP, Félix TM, Scarano G, Llerena JC, Vargas FR, Moreira MÂM, Seuánez HN, Castilla EE, Orioli IM. Molecular analysis of holoprosencephaly in South America. Genet Mol Biol 2014; 37:250-62. [PMID: 24764759 PMCID: PMC3983586 DOI: 10.1590/s1415-47572014000200011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Holoprosencephaly (HPE) is a spectrum of brain and facial malformations primarily reflecting genetic factors, such as chromosomal abnormalities and gene mutations. Here, we present a clinical and molecular analysis of 195 probands with HPE or microforms; approximately 72% of the patients were derived from the Latin American Collaborative Study of Congenital Malformations (ECLAMC), and 82% of the patients were newborns. Alobar HPE was the predominant brain defect in almost all facial defect categories, except for patients without oral cleft and median or lateral oral clefts. Ethmocephaly, cebocephaly, and premaxillary agenesis were primarily observed among female patients. Premaxillary agenesis occurred in six of the nine diabetic mothers. Recurrence of HPE or microform was approximately 19%. The frequency of microdeletions, detected using Multiplex Ligation-dependant Probe Amplification (MLPA) was 17% in patients with a normal karyotype. Cytogenetics or QF-PCR analyses revealed chromosomal anomalies in 27% of the probands. Mutational analyses in genes SHH, ZIC2, SIX3 and TGIF were performed in 119 patients, revealing eight mutations in SHH, two mutations in SIX3 and two mutations in ZIC2. Thus, a detailed clinical description of new HPE cases with identified genetic anomalies might establish genotypic and phenotypic correlations and contribute to the development of additional strategies for the analysis of new cases.
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Affiliation(s)
- Clarice Pagani Savastano
- Estudo Colaborativo Latino Americano de Malformações Congênitas, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil . ; Instituto Nacional de Genética Médica Populacional, Rio de Janeiro, RJ, Brazil
| | - Kênia Balbi El-Jaick
- Departamento de Genética e Biologia Molecular, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | | | | | - Sebastiano Bianca
- Centro di Consulenza Genetica e di Teratologia della Riproduzione, Dipartimento Materno Infantile, ARNAS Garibaldi Nesima, Catania, CT, Italy
| | | | - Têmis Maria Félix
- Serviço de Genética Médica, Hospital das Clínicas de Porto Alegre, Porto Alegre, RS, Brazil
| | - Gioacchino Scarano
- Registro Campano Difetti Congeniti, Azienda Ospedaliera "Gaetano Rummo", Benevento, BN, Italy
| | - Juan Clinton Llerena
- Centro de Genética Médica, Instituto Fernandes Figueira, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Fernando Regla Vargas
- Departamento de Genética e Biologia Molecular, Universidade Federal do Estado do Rio de Janeiro, Rio de Janeiro, RJ, Brazil . ; Estudo Colaborativo Latino Americano de Malformações Congênitas, Laboratório de Epidemiologia de Defeitos Congênitos, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | | | - Hector N Seuánez
- Programa de Genética, Instituto Nacional de Câncer, Rio de Janeiro, RJ, Brazil
| | - Eduardo Enrique Castilla
- Instituto Nacional de Genética Médica Populacional, Rio de Janeiro, RJ, Brazil . ; Estudio Colaborativo Latino Americano de Malformaciones Congenitas, Centro de Educación Médica e Investigación Clínica, Buenos Aires, Argentina
| | - Iêda Maria Orioli
- Estudo Colaborativo Latino Americano de Malformações Congênitas, Departamento de Genética, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil . ; Instituto Nacional de Genética Médica Populacional, Rio de Janeiro, RJ, Brazil
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33
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Savastano CP, Bernardi P, Seuánez HN, Moreira MÂM, Orioli IM. Rare nasal cleft in a patient with holoprosencephaly due to a mutation in the ZIC2 gene. ACTA ACUST UNITED AC 2014; 100:300-6. [PMID: 24677696 DOI: 10.1002/bdra.23216] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 12/08/2013] [Accepted: 12/12/2013] [Indexed: 01/13/2023]
Abstract
BACKGROUND Holoprosencephaly (HPE) is a spectrum of midline malformations of the prosencephalon generally reflected in a continuum of midline facial anomalies. Patients with mutation in the ZIC2 gene usually present a normal or mildly dysmorphic face associated with a severe brain malformation. Here we present a rare unilateral nasal cleft (Tessier cleft n. 1) with holoprosencephaly in a patient with a ZIC2 mutation. CASE The male newborn presented with alobar HPE, microcephaly, ocular hypertelorism, upslanting palpebral fissures, a bulky nose with a left paramedian alar cleft. Mutational screening for HPE genes revealed the occurrence of a frameshift mutation in the ZIC2 gene. The mutation was inherited from the father who presented only mild ocular hypotelorism but had an affected child with HPE from his first marriage. CONCLUSION The occurrence of oral clefts is common in patients with HPE, but unusual in patients with mutation in the ZIC2 gene. To our knowledge, clefts of the nasal alae have been reported only once or twice in patients with ZIC2 mutations. In documented patients from the literature, only 2% of individuals with described pathogenic mutations in the ZIC2 gene (3/171) presented facial clefts, one of them a nasal cleft, while common oral clefts were observed in 27% of individuals (7/26) described with nonpathogenic ZIC2 mutations or presenting a concomitant mutation in another HPE gene. When compared with the general population, nasal clefts are common in ZIC2 mutations and these mutations must be searched for in undiagnosed cases.
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Affiliation(s)
- Clarice Pagani Savastano
- Estudo Colaborativo Latino Americano de Malformações Congênitas (ECLAMC), Departamento de Genética, Universidade Federal do Rio de Janeiro, Brazil; INAGEMP - Instituto Nacional de Genética Médica Populacional, Rio de Janeiro, Brazil
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34
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Quintana A, Garabedian MJ, Wallerstein RJ. Antenatal detection of maternal unipartental disomy of chromosome 2 in a fetus with non-chromosomal, non-syndromic alobar holoprosencephaly. Am J Med Genet A 2013; 164A:276-8. [PMID: 24243683 DOI: 10.1002/ajmg.a.36204] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2013] [Accepted: 07/29/2013] [Indexed: 11/10/2022]
Affiliation(s)
- Andrea Quintana
- Department of Obstetrics and Gynecology, Santa Clara Valley Medical Center, San Jose, California
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35
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Hong M, Krauss RS. Rescue of holoprosencephaly in fetal alcohol-exposed Cdon mutant mice by reduced gene dosage of Ptch1. PLoS One 2013; 8:e79269. [PMID: 24244464 PMCID: PMC3823703 DOI: 10.1371/journal.pone.0079269] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Accepted: 09/25/2013] [Indexed: 11/18/2022] Open
Abstract
Holoprosencephaly (HPE) is a commonly occurring developmental defect in which midline patterning of the forebrain and midface is disrupted. Sonic hedgehog (SHH) signaling is required during multiple stages of rostroventral midline development, and heterozygous mutations in SHH pathway components are associated with HPE. However, clinical presentation of HPE is highly variable, and carriers of heterozygous mutations often lack apparent defects. It is therefore thought that such mutations must interact with more common modifiers, genetic and/or environmental. We have modeled this scenario in mice. Cdon mutant mice have a largely subthreshold defect in SHH signaling, rendering them sensitive to a wide spectrum of HPE phenotypes by additional hits that are themselves insufficient to produce HPE, including transient in utero exposure to ethanol. These variable HPE phenotypes may arise in embryos that fail to reach a threshold level of SHH signaling at a specific developmental stage. To provide evidence for this possibility, here we tested the effect of removing one copy of the negative regulator Ptch1 from Cdon(-/-) embryos and compared their response to ethanol with that of Cdon(-/-);Ptch1(+/+) embryos. Ptch1 heterozygosity decreased the penetrance of HPE in this system by >75%. The major effect of reduced Ptch1 gene dosage was on penetrance, as those Cdon(-/-);Ptch1(+/-) embryos that displayed HPE did not show major differences in phenotype from Cdon(-/-);Ptch1(+/+) embryos with ethanol-induced HPE. Our findings are consistent with the notion that even in an etiologically complex model of HPE, the level of SHH pathway activity is rate-limiting. Furthermore, the clinical outcome of an individual carrying a SHH pathway mutation will likely reflect the sum effect of both deleterious and protective modifier alleles and their interaction with non-genetic risk factors like fetal alcohol exposure.
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Affiliation(s)
- Mingi Hong
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
| | - Robert S. Krauss
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, New York, United States of America
- * E-mail:
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Simonis N, Migeotte I, Lambert N, Perazzolo C, de Silva DC, Dimitrov B, Heinrichs C, Janssens S, Kerr B, Mortier G, Van Vliet G, Lepage P, Casimir G, Abramowicz M, Smits G, Vilain C. FGFR1 mutations cause Hartsfield syndrome, the unique association of holoprosencephaly and ectrodactyly. J Med Genet 2013; 50:585-92. [PMID: 23812909 PMCID: PMC3756455 DOI: 10.1136/jmedgenet-2013-101603] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Background Harstfield syndrome is the rare and unique association of holoprosencephaly (HPE) and ectrodactyly, with or without cleft lip and palate, and variable additional features. All the reported cases occurred sporadically. Although several causal genes of HPE and ectrodactyly have been identified, the genetic cause of Hartsfield syndrome remains unknown. We hypothesised that a single key developmental gene may underlie the co-occurrence of HPE and ectrodactyly. Methods We used whole exome sequencing in four isolated cases including one case-parents trio, and direct Sanger sequencing of three additional cases, to investigate the causative variants in Hartsfield syndrome. Results We identified a novel FGFR1 mutation in six out of seven patients. Affected residues are highly conserved and are located in the extracellular binding domain of the receptor (two homozygous mutations) or the intracellular tyrosine kinase domain (four heterozygous de novo variants). Strikingly, among the six novel mutations, three are located in close proximity to the ATP's phosphates or the coordinating magnesium, with one position required for kinase activity, and three are adjacent to known mutations involved in Kallmann syndrome plus other developmental anomalies. Conclusions Dominant or recessive FGFR1 mutations are responsible for Hartsfield syndrome, consistent with the known roles of FGFR1 in vertebrate ontogeny and conditional Fgfr1-deficient mice. Our study shows that, in humans, lack of accurate FGFR1 activation can disrupt both brain and hand/foot midline development, and that FGFR1 loss-of-function mutations are responsible for a wider spectrum of clinical anomalies than previously thought, ranging in severity from seemingly isolated hypogonadotropic hypogonadism, through Kallmann syndrome with or without additional features, to Hartsfield syndrome at its most severe end.
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Affiliation(s)
- Nicolas Simonis
- Laboratoire de Bioinformatique des Génomes et des Réseaux (BiGRe), Université Libre de Bruxelles (ULB), Brussels, Belgium
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Mercier S, David V, Ratié L, Gicquel I, Odent S, Dupé V. NODAL and SHH dose-dependent double inhibition promotes an HPE-like phenotype in chick embryos. Dis Model Mech 2012; 6:537-43. [PMID: 23264560 PMCID: PMC3597036 DOI: 10.1242/dmm.010132] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Holoprosencephaly (HPE) is a common congenital defect that results from failed or incomplete forebrain cleavage. HPE is characterized by a wide clinical spectrum, with inter- and intrafamilial variability. This heterogeneity is not well understood and it has been suggested that HPE involves a combination of multiple gene mutations. In this model, several mutated alleles or modifying factors are presumed to act in synergy to cause and determine the severity of HPE. This could explain the various clinical phenotypes. Screening for HPE-associated genes in humans suggests the involvement of NODAL or SHH signaling, or both. To test this multigenic hypothesis, we investigated the effects of chemical inhibition of these two main HPE signaling pathways in a chick embryo model. SB-505124, a selective inhibitor of transforming growth factor-B type I receptors was used to inhibit the NODAL pathway. Cyclopamine was used to inhibit the SHH pathway. We report that both inhibitors caused HPE-like defects that were dependent on the drug concentration and on the developmental stage at the time of treatment. We also investigated double inhibition of NODAL and SHH pathways from the onset of gastrulation by using subthreshold inhibitor concentrations. The inhibitors of the NODAL and SHH pathways, even at low concentration, acted synergistically to promote an HPE-like phenotype. These findings support the view that genetic heterogeneity is important in the etiology of HPE and may contribute to the phenotypic variability.
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Affiliation(s)
- Sandra Mercier
- Institut de Génétique et Développement, CNRS UMR6290, Université de Rennes 1, IFR140 GFAS, Faculté de Médecine, 35043 Rennes, France
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38
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Hong M, Krauss RS. Cdon mutation and fetal ethanol exposure synergize to produce midline signaling defects and holoprosencephaly spectrum disorders in mice. PLoS Genet 2012; 8:e1002999. [PMID: 23071453 PMCID: PMC3469434 DOI: 10.1371/journal.pgen.1002999] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 08/14/2012] [Indexed: 11/18/2022] Open
Abstract
Holoprosencephaly (HPE) is a remarkably common congenital anomaly characterized by failure to define the midline of the forebrain and midface. HPE is associated with heterozygous mutations in Sonic hedgehog (SHH) pathway components, but clinical presentation is extremely variable and many mutation carriers are unaffected. It has been proposed that these observations are best explained by a multiple-hit model, in which the penetrance and expressivity of an HPE mutation is enhanced by a second mutation or the presence of cooperating, but otherwise silent, modifier genes. Non-genetic risk factors are also implicated in HPE, and gene-environment interactions may provide an alternative multiple-hit model to purely genetic multiple-hit models; however, there is little evidence for this contention. We report here a mouse model in which there is dramatic synergy between mutation of a bona fide HPE gene (Cdon, which encodes a SHH co-receptor) and a suspected HPE teratogen, ethanol. Loss of Cdon and in utero ethanol exposure in 129S6 mice give little or no phenotype individually, but together produce defects in early midline patterning, inhibition of SHH signaling in the developing forebrain, and a broad spectrum of HPE phenotypes. Our findings argue that ethanol is indeed a risk factor for HPE, but genetically predisposed individuals, such as those with SHH pathway mutations, may be particularly susceptible. Furthermore, gene-environment interactions are likely to be important in the multifactorial etiology of HPE.
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Affiliation(s)
| | - Robert S. Krauss
- Department of Developmental and Regenerative Biology, Mount Sinai School of Medicine, New York, New York, United States of America
- * E-mail:
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39
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Roessler E, Hu P, Hong SK, Srivastava K, Carrington B, Sood R, Petrykowska H, Elnitski L, Ribeiro LA, Richieri-Costa A, Feldman B, Odenwald WF, Muenke M. Unique alterations of an ultraconserved non-coding element in the 3'UTR of ZIC2 in holoprosencephaly. PLoS One 2012; 7:e39026. [PMID: 22859937 PMCID: PMC3409191 DOI: 10.1371/journal.pone.0039026] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 05/15/2012] [Indexed: 01/23/2023] Open
Abstract
Coding region alterations of ZIC2 are the second most common type of mutation in holoprosencephaly (HPE). Here we use several complementary bioinformatic approaches to identify ultraconserved cis-regulatory sequences potentially driving the expression of human ZIC2. We demonstrate that an 804 bp element in the 3′ untranslated region (3′UTR) is highly conserved across the evolutionary history of vertebrates from fish to humans. Furthermore, we show that while genetic variation of this element is unexpectedly common among holoprosencephaly subjects (6/528 or >1%), it is not present in control individuals. Two of six proband-unique variants are de novo, supporting their pathogenic involvement in HPE outcomes. These findings support a general recommendation that the identification and analysis of key ultraconserved elements should be incorporated into the genetic risk assessment of holoprosencephaly cases.
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Affiliation(s)
- Erich Roessler
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ping Hu
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Sung-Kook Hong
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Kshitij Srivastava
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Blake Carrington
- Zebrafish Core Facility, Genetics and Molecular Biology Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Raman Sood
- Zebrafish Core Facility, Genetics and Molecular Biology Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Hanna Petrykowska
- Genome Technology Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Laura Elnitski
- Genome Technology Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Lucilene A. Ribeiro
- Molecular Genetics Laboratory and Clinical Genetics Service, Hospital for Rehabilitation and Craniofacial Anomalies, USP, Bauru, Brazil
| | - Antonio Richieri-Costa
- Molecular Genetics Laboratory and Clinical Genetics Service, Hospital for Rehabilitation and Craniofacial Anomalies, USP, Bauru, Brazil
| | - Benjamin Feldman
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
| | - Ward F. Odenwald
- Neural Cell-Fate Determinants Section, National Institute of Neurological Diseases and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Maximilian Muenke
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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Ribeiro LA, Roessler E, Hu P, Pineda-Alvarez DE, Zhou N, Jones M, Chandrasekharappa S, Richieri-Costa A, Muenke M. Comparison of mutation findings in ZIC2 between microform and classical holoprosencephaly in a Brazilian cohort. ACTA ACUST UNITED AC 2012; 94:912-7. [PMID: 22847929 DOI: 10.1002/bdra.23047] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 05/10/2012] [Accepted: 05/23/2012] [Indexed: 01/05/2023]
Abstract
BACKGROUND Holoprosencephaly is the most frequent congenital malformation of the forebrain in humans. It is anatomically classified by the relative degree of abnormal formation and separation of the developing central nervous system. Mutations of ZIC2 are the second most common heterozygous variations detected in holoprosencephaly (HPE) patients. Mutations in most known HPE genes typically result in variable phenotypes that rage from classic alobar HPE to microforms represented by hypotelorism, solitary central maxillary incisor (SCMI), and cleft lip/palate, among others. Patients with HPE owing to ZIC2 mutations have recently been described by a distinct phenotype compared with mutations in other HPE causative genes. METHODS We report the comparison of ZIC2 molecular findings by Sanger bidirectional DNA sequencing and ad hoc genotyping in a cohort of 105 Brazilian patients within the clinical spectrum of HPE, including classic and microform groups. RESULTS We detected a total of five variants in the ZIC2 gene: a common histidine tract expansion c.716_718dup (p.His239dup), a rare c.1377_1391del_homozygous (p.Ala466_470del, or Ala 15 to 10 contraction), a novel intronic c.1239+18G>A variant, a novel frameshift c.1215dupC (p.Ser406Glnfs*11), and a c.1401_1406dup (p.Ala469_470dup, or alanine tract expansion to 17 residues). CONCLUSIONS From these patients, only the latter two mutations found in classic HPE are likely to be medically significant. In contrast, variants detected in the microform group are not likely to be pathogenic. We show conclusively that the histidine tract expansion is a polymorphic alteration that demonstrates considerable differences in allele frequencies across different ethnic groups. Therefore, careful population studies of rare variants can improve genotype-phenotype correlations. Birth Defects Research (Part A) 2012.
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Affiliation(s)
- Lucilene A Ribeiro
- Molecular Genetics Laboratory and Clinical Genetics Service, Hospital for Rehabilitation and Craniofacial Anomalies, University of Sao Paolo, Bauru, Sao Paolo, Brazil
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Srivastava K, Hu P, Solomon BD, Ming JE, Roessler E, Muenke M. Molecular analysis of the Noggin (NOG) gene in holoprosencephaly patients. Mol Genet Metab 2012; 106:241-3. [PMID: 22503063 PMCID: PMC3356444 DOI: 10.1016/j.ymgme.2012.03.008] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 03/14/2012] [Accepted: 03/14/2012] [Indexed: 11/19/2022]
Abstract
Holoprosencephaly (HPE) is the most common structural anomaly of the human forebrain. Various genetic and teratogenic causes have been implicated in its pathogenesis. A recent report in mice described Noggin (NOG) as a candidate gene involved in the etiogenesis of microform HPE. Here, we present for the first time genetic analysis of a large HPE cohort for sequence variations in NOG. On the basis of our study, we conclude that mutations in the coding region of NOG are rare, and play at most an uncommon role in human HPE.
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Affiliation(s)
- Kshitij Srivastava
- 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
| | - Benjamin D. Solomon
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, Maryland
| | - Jeffrey E. Ming
- The Children’s Hospital of Philadelphia, Division of Human Genetics and Molecular Biology, Philadelphia, Pennsylvania
| | - Erich Roessler
- 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
- Correspondence: Maximilian Muenke, MD, Chief, Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, 35 Convent Drive, Building 35, Room 1B-203, Bethesda, MD-20892, , Phone: 301-402-8167, FAX: 301-496-7184
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Vaaralahti K, Raivio T, Koivu R, Valanne L, Laitinen EM, Tommiska J. Genetic Overlap between Holoprosencephaly and Kallmann Syndrome. Mol Syndromol 2012; 3:1-5. [PMID: 22855648 DOI: 10.1159/000338706] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/03/2012] [Indexed: 11/19/2022] Open
Abstract
Patients with Kallmann syndrome (KS; congenital hypogonadotropic hypogonadism and decreased/absent sense of smell), septo-optic dysplasia (SOD), or holoprosencephaly (HPE) reportedly have midline defects. In this study, we investigate a genetic overlap between KS, SOD, and HPE. Nineteen subjects (18 males, 1 female) with KS and without mutations in the known KS genes were screened for mutations in SOX2, SHH, SIX3,TGIF1,TDGF1,FOXH1,GLI2, and GLI3. One male carried 2 heterozygous missense changes, one in SIX3 (c.428G>A, p.G143D) and the other in GLI2 (c.2509G>A, p.E837K). Both of these genes have been implicated in the etiology of HPE and neither of these changes were present in 200 control subjects. Other variants found among the subjects were known polymorphisms. KS and HPE may display a genetic overlap. The involvement of genes implicated in the etiology of midline defects in patients with KS warrants further studies.
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Affiliation(s)
- K Vaaralahti
- Institute of Biomedicine/Physiology, University of Helsinki, Finland
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