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Apam-Garduño D, Cortés-González V, Quintana-Fernández L, Martínez-Anaya D, Pérez-Vera P, Villanueva-Mendoza C. The relevance of the cytogenetic analysis in syndromic microphthalmia/anophthalmia. Ophthalmic Genet 2019; 40:584-587. [PMID: 31809626 DOI: 10.1080/13816810.2019.1698618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- David Apam-Garduño
- Genetics, Hospital "Dr. Luis Sánchez Bulnes" Asociación para Evitar la Ceguera en México, Mexico
| | - Vianney Cortés-González
- Genetics, Hospital "Dr. Luis Sánchez Bulnes" Asociación para Evitar la Ceguera en México, Mexico
| | - Luis Quintana-Fernández
- Ophthalmology, Hospital "Dr. Luis Sánchez Bulnes" Asociación para Evitar la Ceguera en México, Mexico
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2
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Genetics of anophthalmia and microphthalmia. Part 1: Non-syndromic anophthalmia/microphthalmia. Hum Genet 2019; 138:799-830. [PMID: 30762128 DOI: 10.1007/s00439-019-01977-y] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 01/30/2019] [Indexed: 12/22/2022]
Abstract
Eye formation is the result of coordinated induction and differentiation processes during embryogenesis. Disruption of any one of these events has the potential to cause ocular growth and structural defects, such as anophthalmia and microphthalmia (A/M). A/M can be isolated or occur with systemic anomalies, when they may form part of a recognizable syndrome. Their etiology includes genetic and environmental factors; several hundred genes involved in ocular development have been identified in humans or animal models. In humans, around 30 genes have been repeatedly implicated in A/M families, although many other genes have been described in single cases or families, and some genetic syndromes include eye anomalies occasionally as part of a wider phenotype. As a result of this broad genetic heterogeneity, with one or two notable exceptions, each gene explains only a small percentage of cases. Given the overlapping phenotypes, these genes can be most efficiently tested on panels or by whole exome/genome sequencing for the purposes of molecular diagnosis. However, despite whole exome/genome testing more than half of patients currently remain without a molecular diagnosis. The proportion of undiagnosed cases is even higher in those individuals with unilateral or milder phenotypes. Furthermore, even when a strong gene candidate is available for a patient, issues of incomplete penetrance and germinal mosaicism make diagnosis and genetic counseling challenging. In this review, we present the main genes implicated in non-syndromic human A/M phenotypes and, for practical purposes, classify them according to the most frequent or predominant phenotype each is associated with. Our intention is that this will allow clinicians to rank and prioritize their molecular analyses and interpretations according to the phenotypes of their patients.
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Ledford KL, Martinez-De Luna RI, Theisen MA, Rawlins KD, Viczian AS, Zuber ME. Distinct cis-acting regions control six6 expression during eye field and optic cup stages of eye formation. Dev Biol 2017; 426:418-428. [PMID: 28438336 PMCID: PMC5500183 DOI: 10.1016/j.ydbio.2017.04.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Revised: 04/07/2017] [Accepted: 04/12/2017] [Indexed: 02/06/2023]
Abstract
The eye field transcription factor, Six6, is essential for both the early (specification and proliferative growth) phase of eye formation, as well as for normal retinal progenitor cell differentiation. While genomic regions driving six6 optic cup expression have been described, the sequences controlling eye field and optic vesicle expression are unknown. Two evolutionary conserved regions 5' and a third 3' to the six6 coding region were identified, and together they faithfully replicate the endogenous X. laevis six6 expression pattern. Transgenic lines were generated and used to determine the onset and expression patterns controlled by the regulatory regions. The conserved 3' region was necessary and sufficient for eye field and optic vesicle expression. In contrast, the two conserved enhancer regions located 5' of the coding sequence were required together for normal optic cup and mature retinal expression. Gain-of-function experiments indicate endogenous six6 and GFP expression in F1 transgenic embryos are similarly regulated in response to candidate trans-acting factors. Importantly, CRISPR/CAS9-mediated deletion of the 3' eye field/optic vesicle enhancer in X. laevis, resulted in a reduction in optic vesicle size. These results identify the cis-acting regions, demonstrate the modular nature of the elements controlling early versus late retinal expression, and identify potential regulators of six6 expression during the early stages of eye formation.
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Affiliation(s)
- Kelley L Ledford
- Department of Ophthalmology and The Center for Vision Research, SUNY Upstate Medical University, Syracuse, NY 13210, United States; Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, United States
| | - Reyna I Martinez-De Luna
- Department of Ophthalmology and The Center for Vision Research, SUNY Upstate Medical University, Syracuse, NY 13210, United States
| | - Matthew A Theisen
- Department of Ophthalmology and The Center for Vision Research, SUNY Upstate Medical University, Syracuse, NY 13210, United States
| | - Karisa D Rawlins
- Department of Ophthalmology and The Center for Vision Research, SUNY Upstate Medical University, Syracuse, NY 13210, United States
| | - Andrea S Viczian
- Department of Ophthalmology and The Center for Vision Research, SUNY Upstate Medical University, Syracuse, NY 13210, United States; Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, United States; Department of Cell & Developmental Biology, SUNY Upstate Medical University, Syracuse, NY 13210, United States; Department of Neuroscience & Physiology, SUNY Upstate Medical University, Syracuse, NY 13210, United States.
| | - Michael E Zuber
- Department of Ophthalmology and The Center for Vision Research, SUNY Upstate Medical University, Syracuse, NY 13210, United States; Department of Biochemistry & Molecular Biology, SUNY Upstate Medical University, Syracuse, NY 13210, United States; Department of Neuroscience & Physiology, SUNY Upstate Medical University, Syracuse, NY 13210, United States
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4
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Latypova X, Bordereau S, Bleriot A, Pichon O, Poulain D, Briand A, Le Caignec C, Isidor B. Mandibular dysostosis without microphthalmia caused by OTX2 deletion. Am J Med Genet A 2016; 170:2466-70. [PMID: 27378064 DOI: 10.1002/ajmg.a.37837] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/23/2016] [Indexed: 11/06/2022]
Abstract
Mutations in OTX2 are mostly identified in patients with anophthalmia/microphthalmia with variable severity. The OTX2 homeobox gene plays a crucial role in craniofacial morphogenesis during early embryo development. We report for the first time a patient with a mandibular dysostosis caused by a 120 kb deletion including the entire coding sequence of OTX2, identified by array CGH. No ocular malformations were identified after extended ophthalmologic examination. Our data refine the clinical spectrum associated with OTX2 mutations and suggests that OTX2 haploinsufficiency should be considered as a possible cause for isolated mandibular dysostosis. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Xénia Latypova
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Sylvain Bordereau
- Service d'Ophtalmologie, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Alice Bleriot
- Service d'Ophtalmologie, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Olivier Pichon
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Damien Poulain
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Annaïg Briand
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Cédric Le Caignec
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France.,INSERM, Laboratoire de Physiopathologie de la Résorption Osseuse et Thérapie des Tumeurs Osseuses Primitives, Nantes, France
| | - Bertrand Isidor
- Service de Génétique Médicale, Centre Hospitalier Universitaire de Nantes, Nantes, France.,INSERM, Laboratoire de Physiopathologie de la Résorption Osseuse et Thérapie des Tumeurs Osseuses Primitives, Nantes, France
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5
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Mauri L, Franzoni A, Scarcello M, Sala S, Garavelli L, Modugno A, Grammatico P, Patrosso MC, Piozzi E, Del Longo A, Gesu GP, Manfredini E, Primignani P, Damante G, Penco S. SOX2, OTX2 and PAX6 analysis in subjects with anophthalmia and microphthalmia. Eur J Med Genet 2014; 58:66-70. [PMID: 25542770 DOI: 10.1016/j.ejmg.2014.12.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 12/04/2014] [Indexed: 01/31/2023]
Abstract
Anophthalmia (A) and microphthalmia (M) are rare developmental anomalies that have significant effects on visual activity. In fraction of A/M subjects, single genetic defects have been identified as causative. In this study we analysed 65 Italian A/M patients, 21 of whom are syndromic, for mutations in SOX2, OTX2 and PAX6 genes. In syndromic patients the presence of genome imbalances through array CGH was also investigated. No mutations were found for OTX2 and PAX6 genes. Three causative SOX2 mutations were found in subjects with syndromic A. In a subject with syndromic signs and monolateral M, two de novo 6.26 Mb and 1.37 Mb deletions in 4q13.2q13.3 have been identified. A SOX2 missense (p.Ala161Ser) mutation was found in 1 out of 39 a subject with non-syndromic monolateral M. Alanine at position 161 is conserved along phylogeny and the p.Ala161Ser mutation is estimated pathogenic by in silico analysis. However, this mutation was also present in the unaffected patient's daughter.
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Affiliation(s)
- Lucia Mauri
- Department of Laboratory Medicine, Medical Genetics, Niguarda Ca' Granda Hospital, Milan, Italy
| | - Alessandra Franzoni
- Institute of Genetics, Azienda Ospedaliero-Universitaria Udine, Udine, Italy
| | - Manuela Scarcello
- Department of Laboratory Medicine, Medical Genetics, Niguarda Ca' Granda Hospital, Milan, Italy
| | - Stefano Sala
- Department of Laboratory Medicine, Medical Genetics, Niguarda Ca' Granda Hospital, Milan, Italy
| | - Livia Garavelli
- Clinical Genetics Unit, IRCCS Arcispedale S. Maria Nuova, Reggio Emilia, Italy
| | | | - Paola Grammatico
- Department of Molecular Medicine, "La Sapienza" University, Rome, Italy
| | - Maria Cristina Patrosso
- Department of Laboratory Medicine, Medical Genetics, Niguarda Ca' Granda Hospital, Milan, Italy
| | - Elena Piozzi
- Pediatric Ophthalmology, Niguarda Ca' Granda Hospital, Milan, Italy
| | | | - Giovanni P Gesu
- Department of Laboratory Medicine, Medical Genetics, Niguarda Ca' Granda Hospital, Milan, Italy
| | - Emanuela Manfredini
- Department of Laboratory Medicine, Medical Genetics, Niguarda Ca' Granda Hospital, Milan, Italy
| | - Paola Primignani
- Department of Laboratory Medicine, Medical Genetics, Niguarda Ca' Granda Hospital, Milan, Italy
| | - Giuseppe Damante
- Institute of Genetics, Azienda Ospedaliero-Universitaria Udine, Udine, Italy; Department of Medical and Biological Sciences, Udine University, Udine, Italy.
| | - Silvana Penco
- Department of Laboratory Medicine, Medical Genetics, Niguarda Ca' Granda Hospital, Milan, Italy.
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6
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Severino M, Allegri AEM, Pistorio A, Roviglione B, Di Iorgi N, Maghnie M, Rossi A. Midbrain-hindbrain involvement in septo-optic dysplasia. AJNR Am J Neuroradiol 2014; 35:1586-92. [PMID: 24763416 DOI: 10.3174/ajnr.a3959] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
BACKGROUND AND PURPOSE Midbrain-hindbrain involvement in septo-optic dysplasia has not been well described, despite reported mutations of genes regulating brain stem patterning. We aimed to describe midbrain-hindbrain involvement in patients with septo-optic dysplasia and to identify possible clinical-neuroimaging correlations. MATERIALS AND METHODS Using MR imaging, we categorized 38 patients (21 males) based on the presence (group A, 21 patients) or absence (group B, 17 patients) of visible brain stem anomalies. We measured height and anteroposterior diameter of midbrain, pons, and medulla, anteroposterior midbrain/pons diameter (M/P ratio), vermian height, and tegmento-vermian angle, and compared the results with 114 healthy age-matched controls. Furthermore, patients were subdivided based on the type of midline anomalies. The associations between clinical and neuroradiological features were investigated. Post hoc tests were corrected according to Bonferroni adjustment (pB). RESULTS Patients with brain stem abnormalities had smaller anteroposterior pons diameter than controls (pB < .0001) and group B (pB = .012), higher M/P ratio than controls (pB < .0001) and group B (pB < .0001), and smaller anteroposterior medulla diameter (pB = .001), pontine height (pB = .00072), and vermian height (pB = .0009) than controls. Six of 21 patients in group A had thickened quadrigeminal plate, aqueductal stenosis, and hydrocephalus; 3 also had agenesis of the epithalamus. One patient had a short midbrain with long pons and large superior vermis. There was a statistically significant association between brain stem abnormalities and callosal dysgenesis (P = .011) and developmental delay (P = .035), respectively. CONCLUSION Midbrain-hindbrain abnormalities are a significant, albeit underrecognized, component of the septo-optic dysplasia spectrum, and are significantly associated with developmental delay in affected patients.
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Affiliation(s)
- M Severino
- From the Neuroradiology Unit (M.S., A.R.)
| | | | - A Pistorio
- Epidemiology and Biostatistics Unit (A.P.), Istituto Giannina Gaslini, Università di Genova, Genoa, Italy
| | | | - N Di Iorgi
- Pediatric Department (A.E.M.A., N.D.I., M.M.)
| | - M Maghnie
- Pediatric Department (A.E.M.A., N.D.I., M.M.)
| | - A Rossi
- From the Neuroradiology Unit (M.S., A.R.)
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7
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Martínez-Frías ML, Ocejo-Vinyals JG, Arteaga R, Martínez-Fernández ML, MacDonald A, Pérez-Belmonte E, Bermejo-Sánchez E, Martínez S. Interstitial deletion 14q22.3-q23.2: Genotype-phenotype correlation. Am J Med Genet A 2013; 164A:639-47. [DOI: 10.1002/ajmg.a.36330] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2013] [Accepted: 10/04/2013] [Indexed: 11/11/2022]
Affiliation(s)
- María Luisa Martínez-Frías
- Departamento de Farmacología; Facultad de Medicina; Universidad Complutense de Madrid; Madrid Spain
- Spanish Collaborative Study of Congenital Malformations (ECEMC); CIAC (Research Center on Congenital Anomalies); Instituto de Salud Carlos III; Madrid Spain
- CIBER de Enfermedades Raras (CIBERER) (U724); Instituto de Salud Carlos III; Ministerio de Economía y Competitividad; Madrid Spain
| | | | - Rosa Arteaga
- Servicio de Neurología; Hospital Universitario Marqués de Valdecilla; Santander Spain
| | - María Luisa Martínez-Fernández
- Spanish Collaborative Study of Congenital Malformations (ECEMC); CIAC (Research Center on Congenital Anomalies); Instituto de Salud Carlos III; Madrid Spain
- CIBER de Enfermedades Raras (CIBERER) (U724); Instituto de Salud Carlos III; Ministerio de Economía y Competitividad; Madrid Spain
| | - Alexandra MacDonald
- Spanish Collaborative Study of Congenital Malformations (ECEMC); CIAC (Research Center on Congenital Anomalies); Instituto de Salud Carlos III; Madrid Spain
| | - Elena Pérez-Belmonte
- Servicio de Pediatría; Hospital Universitario Marqués de Valdecilla; Santander Spain
| | - Eva Bermejo-Sánchez
- Spanish Collaborative Study of Congenital Malformations (ECEMC); CIAC (Research Center on Congenital Anomalies); Instituto de Salud Carlos III; Madrid Spain
- CIBER de Enfermedades Raras (CIBERER) (U724); Instituto de Salud Carlos III; Ministerio de Economía y Competitividad; Madrid Spain
- Instituto de Investigación de Enfermedades Raras (IIER); Instituto de Salud Carlos III. Ministerio de Economía y Competitividad; Madrid Spain
| | - Salvador Martínez
- Instituto de Neurociencias de Alicante; CSIC-UMH; San Juan de Alicante Spain
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8
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Martínez-Fernández ML, Bermejo-Sánchez E, Fernández B, MacDonald A, Fernández-Toral J, Martínez-Frías ML. Haploinsufficiency ofBMP4gene may be the underlying cause of Frías syndrome. Am J Med Genet A 2013; 164A:338-45. [DOI: 10.1002/ajmg.a.36224] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 08/07/2013] [Indexed: 11/05/2022]
Affiliation(s)
- María Luisa Martínez-Fernández
- CIBER de Enfermedades Raras (CIBERER) (U724); Instituto de Salud Carlos III, Ministerio de Economía y Competitividad; Madrid Spain
- Spanish Collaborative Study of Congenital Malformations (ECEMC); CIAC (Research Center on Congenital Anomalies), Instituto de Salud Carlos III; Madrid Spain
| | - Eva Bermejo-Sánchez
- CIBER de Enfermedades Raras (CIBERER) (U724); Instituto de Salud Carlos III, Ministerio de Economía y Competitividad; Madrid Spain
- Spanish Collaborative Study of Congenital Malformations (ECEMC); CIAC (Research Center on Congenital Anomalies), Instituto de Salud Carlos III; Madrid Spain
- Instituto de Investigación de Enfermedades Raras (IIER); Instituto de Salud Carlos III, Ministerio de Economía y Competitividad; Madrid Spain
| | - Belén Fernández
- Servicio de Neonatología; Hospital Universitario Central de Asturias; Oviedo (Asturias) Spain
| | - Alexandra MacDonald
- Spanish Collaborative Study of Congenital Malformations (ECEMC); CIAC (Research Center on Congenital Anomalies), Instituto de Salud Carlos III; Madrid Spain
| | - Joaquín Fernández-Toral
- Servicio de Genética, Hospital Universitario Central de Asturias, Facultad de Medicina; Universidad de Oviedo; Oviedo (Asturias) Spain
| | - María Luisa Martínez-Frías
- CIBER de Enfermedades Raras (CIBERER) (U724); Instituto de Salud Carlos III, Ministerio de Economía y Competitividad; Madrid Spain
- Spanish Collaborative Study of Congenital Malformations (ECEMC); CIAC (Research Center on Congenital Anomalies), Instituto de Salud Carlos III; Madrid Spain
- Departamento de Farmacología, Facultad de Medicina; Universidad Complutense de Madrid; Madrid Spain
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9
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Lumaka A, Van Hole C, Casteels I, Ortibus E, De Wolf V, Vermeesch JR, Lukusa T, Devriendt K. Variability in expression of a familial 2.79 Mb microdeletion in chromosome14q22.1-22.2. Am J Med Genet A 2012; 158A:1381-7. [DOI: 10.1002/ajmg.a.35353] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2011] [Accepted: 01/29/2012] [Indexed: 01/09/2023]
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10
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Pearce ZD, Droste PJ, Aaberg TM, Hassan AS. Ophthalmic and Systemic Findings in Interstitial Deletions of Chromosome 14q: A Case Feport and Literature Review. Ophthalmic Genet 2012; 33:161-6. [DOI: 10.3109/13816810.2012.655359] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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11
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Di Iorgi N, Allegri AEM, Napoli F, Bertelli E, Olivieri I, Rossi A, Maghnie M. The use of neuroimaging for assessing disorders of pituitary development. Clin Endocrinol (Oxf) 2012; 76:161-76. [PMID: 21955099 DOI: 10.1111/j.1365-2265.2011.04238.x] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Magnetic resonance imaging (MRI) is the radiological examination method of choice for evaluating hypothalamo-pituitary-related endocrine disease and is considered essential in the assessment of patients with suspected hypothalamo-pituitary pathology. Physicians involved in the care of such patients have, in MRI, a valuable tool that can aid them in determining the pathogenesis of their patients' underlying pituitary conditions. Indeed, the use of MRI has led to an enormous increase in our knowledge of pituitary morphology, improving, in particular, the differential diagnosis of hypopituitarism. Specifically, MRI allows detailed and precise anatomical study of the pituitary gland by differentiating between the anterior and posterior pituitary lobes. MRI recognition of pituitary hyperintensity in the posterior part of the sella, now considered a marker of neurohypophyseal functional integrity, has been the most striking finding in the diagnosis and understanding of certain forms of 'idiopathic' and permanent growth hormone deficiency (GHD). Published data show a number of correlations between pituitary abnormalities as observed on MRI and a patient's endocrine profile. Indeed, several trends have emerged and have been confirmed: (i) a normal MRI or anterior pituitary hypoplasia generally indicates isolated growth hormone deficiency that is mostly transient and resolves upon adult height achievement; (ii) patients with multiple pituitary hormone deficiencies (MPHD) seldom show a normal pituitary gland; and (iii) the classic triad of ectopic posterior pituitary, pituitary stalk hypoplasia/agenesis and anterior pituitary hypoplasia is more frequently reported in MPHD patients and is generally associated with permanent GHD. Pituitary abnormalities have also been reported in patients with hypopituitarism carrying mutations in several genes encoding transcription factors. Establishing endocrine and MRI phenotypes is extremely useful for the selection and management of patients with hypopituitarism, both in terms of possible genetic counselling and in the early diagnosis of evolving anterior pituitary hormone deficiencies. Going forward, neuroimaging techniques are expected to progressively expand and improve our knowledge and understanding of pituitary diseases.
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Affiliation(s)
- Natascia Di Iorgi
- Department of Paediatrics, IRCCS G. Gaslini, University of Genova, Genova, Italy
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12
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Abstract
PURPOSE OF REVIEW To summarize recent breakthroughs regarding the genes known to play a role in normal ocular development in humans and to elucidate the role mutations in these genes play in anophthalmia and microphthalmia. RECENT FINDINGS The main themes discussed within this article are the various documented genetic advances in identifying the various causes of anophthalmia and microphthalmia. In addition, the complex interplay of these genes during critical embryonic development will be addressed. SUMMARY The recent identification of many eye development genes has changed the ability to identify a cause of anophthalmia and microphthalmia in many individuals. Syndrome identification and the availability of genetic testing underscores the desirability of evaluation by a geneticist for all individuals with anophthalmia and microphthalmia in order to provide appropriate management, long-term guidance, and genetic counseling.
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13
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Peca D, Petrini S, Tzialla C, Boldrini R, Morini F, Stronati M, Carnielli VP, Cogo PE, Danhaive O. Altered surfactant homeostasis and recurrent respiratory failure secondary to TTF-1 nuclear targeting defect. Respir Res 2011; 12:115. [PMID: 21867529 PMCID: PMC3179724 DOI: 10.1186/1465-9921-12-115] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Accepted: 08/25/2011] [Indexed: 01/30/2023] Open
Abstract
Background Mutations of genes affecting surfactant homeostasis, such as SFTPB, SFTPC and ABCA3, lead to diffuse lung disease in neonates and children. Haploinsufficiency of NKX2.1, the gene encoding the thyroid transcription factor-1 (TTF-1) - critical for lung, thyroid and central nervous system morphogenesis and function - causes a rare form of progressive respiratory failure designated brain-lung-thyroid syndrome. Molecular mechanisms involved in this syndrome are heterogeneous and poorly explored. We report a novel TTF-1 molecular defect causing recurrent respiratory failure episodes in an infant. Methods The subject was an infant with severe neonatal respiratory distress syndrome followed by recurrent respiratory failure episodes, hypopituitarism and neurological abnormalities. Lung histology and ultrastructure were assessed by surgical biopsy. Surfactant-related genes were studied by direct genomic DNA sequencing and array chromatine genomic hybridization (aCGH). Surfactant protein expression in lung tissue was analyzed by confocal immunofluorescence microscopy. For kinetics studies, surfactant protein B and disaturated phosphatidylcholine (DSPC) were isolated from serial tracheal aspirates after intravenous administration of stable isotope-labeled 2H2O and 13C-leucine; fractional synthetic rate was derived from gas chromatography/mass spectrometry 2H and 13C enrichment curves. Six intubated infants with no primary lung disease were used as controls. Results Lung biopsy showed desquamative interstitial pneumonitis and lamellar body abnormalities suggestive of genetic surfactant deficiency. Genetic studies identified a heterozygous ABCA3 mutation, L941P, previously unreported. No SFTPB, SFTPC or NKX2.1 mutations or deletions were found. However, immunofluorescence studies showed TTF-1 prevalently expressed in type II cell cytoplasm instead of nucleus, indicating defective nuclear targeting. This pattern has not been reported in human and was not found in two healthy controls and in five ABCA3 mutation carriers. Kinetic studies demonstrated a marked reduction of SP-B synthesis (43.2 vs. 76.5 ± 24.8%/day); conversely, DSPC synthesis was higher (12.4 vs. 6.3 ± 0.5%/day) compared to controls, although there was a marked reduction of DSPC content in tracheal aspirates (29.8 vs. 56.1 ± 12.4% of total phospholipid content). Conclusion Defective TTF-1 signaling may result in profound surfactant homeostasis disruption and neonatal/pediatric diffuse lung disease. Heterozygous ABCA3 missense mutations may act as disease modifiers in other genetic surfactant defects.
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Affiliation(s)
- Donatella Peca
- Department of Medical and Surgical Neonatology, Bambino Gesù Children's Hospital IRCCS, Rome, Italy
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14
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Pericentric inversion, inv(14)(p11.2q22.3), in a 9-month old with features of Goldenhar syndrome. Clin Dysmorphol 2010; 19:185-189. [DOI: 10.1097/mcd.0b013e3283359386] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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15
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Dateki S, Kosaka K, Hasegawa K, Tanaka H, Azuma N, Yokoya S, Muroya K, Adachi M, Tajima T, Motomura K, Kinoshita E, Moriuchi H, Sato N, Fukami M, Ogata T. Heterozygous orthodenticle homeobox 2 mutations are associated with variable pituitary phenotype. J Clin Endocrinol Metab 2010; 95:756-64. [PMID: 19965921 DOI: 10.1210/jc.2009-1334] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
CONTEXT Although recent studies have suggested a positive role of OTX2 in pituitary as well as ocular development and function, detailed pituitary phenotypes in OTX2 mutations and OTX2 target genes for pituitary function other than HESX1 and POU1F1 remain to be determined. OBJECTIVE We aimed to examine such unresolved issues. SUBJECTS We studied 94 Japanese patients with various ocular or pituitary abnormalities. RESULTS We identified heterozygous p.K74fsX103 in case 1, p.A72fsX86 in case 2, p.G188X in two unrelated cases (3 and 4), and a 2,860,561-bp microdeletion involving OTX2 in case 5. Clinical studies revealed isolated GH deficiency in cases 1 and 5; combined pituitary hormone deficiency in case 3; abnormal pituitary structures in cases 1, 3, and 5; and apparently normal pituitary function in cases 2 and 4, together with ocular anomalies in cases 1-5. The wild-type Orthodenticle homeobox 2 (OTX2) protein transactivated the GNRH1 promoter as well as the HESX1, POU1F1, and IRBP (interstitial retinoid-binding protein) promoters, whereas the p.K74fsX103-OTX2 and p.A72fsX86-OTX2 proteins had no transactivation functions and the p.G188X-OTX2 protein had reduced ( approximately 50%) transactivation functions for the four promoters, with no dominant-negative effect. cDNA screening identified positive OTX2 expression in the hypothalamus. CONCLUSIONS The results imply that OTX2 mutations are associated with variable pituitary phenotype, with no genotype-phenotype correlations, and that OTX2 can transactivate GNRH1 as well as HESX1 and POU1F1.
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Affiliation(s)
- Sumito Dateki
- Department of Endocrinology and Metabolism, National Research Institute for Child Health and Development, 2-10-1 Ohkura, Setagaya, Tokyo 157-8535, Japan
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Al-Gazali L, Shather B, Kaplan W, Algawi K, Ali BR. Anterior segment anomalies of the eye, growth retardation associated with hypoplastic pituitary gland and endocrine abnormalities: Jung syndrome or a new syndrome? Am J Med Genet A 2009; 149A:251-6. [PMID: 19161143 DOI: 10.1002/ajmg.a.32626] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
We report on two children from an inbred Arab family with anterior segment anomalies of the eyes, growth retardation, associated with small pituitary gland, and endocrine abnormalities. The features in the sibs in this report are similar to those described in Peters-plus syndrome. However, small pituitary gland associated with growth hormone deficiency has not been reported in Peters-plus syndrome. In addition, sequencing of the B3GALTL gene, the gene implicated in Peters-plus syndrome did not reveal any mutation in the sibs reported here. The association of anterior segment anomalies of the eye, growth retardation, and endocrine problems has previously been described by Jung et al. in 1995. We suggest that the features in the children in this report could represent variable manifestation of this syndrome or previously not described syndrome.
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Affiliation(s)
- Lihadh Al-Gazali
- Department of Paediatrics and Pathology, Faculty of Medicine & Health Sciences, UAE University, Al Ain, UAE.
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Mihelec M, St Heaps L, Flaherty M, Billson F, Rudduck C, Tam PPL, Grigg JR, Peters GB, Jamieson RV. Chromosomal rearrangements and novel genes in disorders of eye development, cataract and glaucoma. Twin Res Hum Genet 2009; 11:412-21. [PMID: 18637741 DOI: 10.1375/twin.11.4.412] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Disorders of eye development such as microphthalmia and anophthalmia (small and absent eyes respectively), anterior segment dysgenesis where there may be pupillary and iris anomalies, and associated cataract and glaucoma, often lead to visual impairment or blindness. Currently treatment options are limited, as much is unknown about the molecular pathways that control normal eye development and induce the aberrant processes that lead to ocular defects. Mutation detection rates in most of the known genes are generally low, emphasizing the genetic heterogeneity of developmental ocular defects. Identification of the disease genes in these conditions improves the clinical information available for affected individuals and families, and provides new insights into the underlying biological processes for facilitation of better treatment options. Investigation of chromosomal rearrangements associated with an ocular phenotype has been especially powerful for disease gene identification. Molecular characterization of such rearrangements, which pinpoints the region by physically disrupting the causative gene or its regulatory sequences, allows for rapid elucidation of underlying genetic factors that contribute to the phenotype. Genes including PAX6, PITX2, FOXC1, MAF, TMEM114, SOX2, OTX2 and BMP4 have been identified in this way to be associated with developmental eye disorders. More recently, new methods in chromosomal analysis such as comparative genomic hybridization (CGH) microarray, have also enhanced our ability in disease gene identification.
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Affiliation(s)
- Marija Mihelec
- Eye Genetics Research Group, Children's Medical Research Institute, The Children's Hospital at Westmead and Save Sight Institute, Sydney, Australia
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Hayashi S, Okamoto N, Makita Y, Hata A, Imoto I, Inazawa J. Heterozygous deletion at 14q22.1-q22.3 including the BMP4 gene in a patient with psychomotor retardation, congenital corneal opacity and feet polysyndactyly. Am J Med Genet A 2008; 146A:2905-10. [PMID: 18925664 DOI: 10.1002/ajmg.a.32519] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Here we report on a 1-year-old Japanese girl with psychomotor retardation, bilateral congenital corneal opacity and bilateral postaxial polysyndactyly of the feet. Although she had a normal female karyotype, our in-house bacterial artificial chromosome (BAC)-based array-CGH analysis successfully detected at least a 2.7-Mb heterozygous deletion at 14q22.1-q22.3 harboring 18 protein-coding genes. Among the genes, BMP4 was a candidate for the gene causing the abnormalities of both the eye and digits. It was previously reported that the BMP family was correlated with the morphogenesis of digits and ocular development, and Bmp4 heterozygous null mice revealed skeletal abnormalities including polydactyly and ocular anterior segment abnormalities. Patients with a deletion including BMP4 also hadabnormalities of the eye and digits. These previous reports support that a haplo-insufficiency of the BMP4 gene likely caused the congenital ocular and digit abnormalities. Moreover, among the other genes contained in the deletion, GMFB is a candidate for the gene responsible for the psychomotor retardation.
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Affiliation(s)
- Shin Hayashi
- Department of Molecular Cytogenetics, Medical Research Institute and School of Biomedical Science, Tokyo Medical and Dental University, Tokyo, Japan
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Dateki S, Fukami M, Sato N, Muroya K, Adachi M, Ogata T. OTX2 mutation in a patient with anophthalmia, short stature, and partial growth hormone deficiency: functional studies using the IRBP, HESX1, and POU1F1 promoters. J Clin Endocrinol Metab 2008; 93:3697-702. [PMID: 18628516 DOI: 10.1210/jc.2008-0720] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
Abstract
CONTEXT OTX2 is a transcription factor gene essential for eye development. Although recent studies suggest the involvement of OTX2 in pituitary function, there is no report demonstrating a positive role of OTX2 in the pituitary function. OBJECTIVE The objective of the study was to report the results of functional studies indicating the relevance of OTX2 to pituitary function. PATIENT A Japanese female patient with bilateral anophthalmia was found to have short stature (height, -3.3 sd) and isolated partial GH deficiency (peak serum GH 3.1 and 9.7 mug/liter after insulin and arginine stimulations, respectively; serum IGF-I 37 ng/ml) at 3 yr 9 months of age. Magnetic resonance imaging delineated apparently normal pituitary gland. RESULTS Mutation analysis showed a de novo heterozygous frameshift mutation (c.402insC) that is predicted to retain the homeodomain but lose the transactivation domain. Functional studies revealed that the wild-type and mutant OTX2 proteins localized to the nucleus and bound to the target sequences within the IRBP (interstitial retinoid-binding protein), HESX1 (HESX homeobox 1), and POU1F1 promoters. Furthermore, the wild-type OTX2 protein markedly transactivated the promoters of IRBP ( approximately 27-fold), HESX1 ( approximately 4.5-fold), and POU1F1 ( approximately 19-fold), whereas the mutant OTX2 protein barely retained the transactivation activities and had no dominant-negative effects. CONCLUSIONS The results provide direct evidence for OTX2 being involved in the pituitary function. It is likely that the heterozygous severe OTX2 loss-of-function mutation caused GH deficiency and short stature, primarily because of decreased transactivation function for HESX1 and POU1F1.
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Affiliation(s)
- Sumito Dateki
- Department of Endocrinology and Metabolism, National Research Institute for Child Health and Development, 2-10-1 Ohkura, Setagaya, Tokyo 157-8535, Japan
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20
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Ou Z, Martin DM, Bedoyan JK, Cooper ML, Chinault AC, Stankiewicz P, Cheung SW. Branchiootorenal syndrome and oculoauriculovertebral spectrum features associated with duplication ofSIX1,SIX6, andOTX2resulting from a complex chromosomal rearrangement. Am J Med Genet A 2008; 146A:2480-9. [DOI: 10.1002/ajmg.a.32398] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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21
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Bakrania P, Efthymiou M, Klein JC, Salt A, Bunyan DJ, Wyatt A, Ponting CP, Martin A, Williams S, Lindley V, Gilmore J, Restori M, Robson AG, Neveu MM, Holder GE, Collin JRO, Robinson DO, Farndon P, Johansen-Berg H, Gerrelli D, Ragge NK. Mutations in BMP4 cause eye, brain, and digit developmental anomalies: overlap between the BMP4 and hedgehog signaling pathways. Am J Hum Genet 2008; 82:304-19. [PMID: 18252212 DOI: 10.1016/j.ajhg.2007.09.023] [Citation(s) in RCA: 191] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Revised: 09/18/2007] [Accepted: 09/24/2007] [Indexed: 11/28/2022] Open
Abstract
Developmental ocular malformations, including anophthalmia-microphthalmia (AM), are heterogeneous disorders with frequent sporadic or non-Mendelian inheritance. Recurrent interstitial deletions of 14q22-q23 have been associated with AM, sometimes with poly/syndactyly and hypopituitarism. We identify two further cases of AM (one with associated pituitary anomalies) with a 14q22-q23 deletion. Using a positional candidate gene approach, we analyzed the BMP4 (Bone Morphogenetic Protein-4) gene and identified a frameshift mutation (c.226del2, p.S76fs104X) that segregated with AM, retinal dystrophy, myopia, brain anomalies, and polydactyly in a family and a nonconservative missense mutation (c.278A-->G, p.E93G) in a highly conserved base in another family. MR imaging and tractography in the c.226del2 proband revealed a primary brain developmental disorder affecting thalamostriatal and callosal pathways, also present in the affected grandmother. Using in situ hybridization in human embryos, we demonstrate expression of BMP4 in optic vesicle, developing retina and lens, pituitary region, and digits strongly supporting BMP4 as a causative gene for AM, pituitary, and poly/syndactyly. Because BMP4 interacts with HH signaling genes in animals, we evaluated gene expression in human embryos and demonstrate cotemporal and cospatial expression of BMP4 and HH signaling genes. We also identified four cases, some of whom had retinal dystrophy, with "low-penetrant" mutations in both BMP4 and HH signaling genes: SHH (Sonic Hedgehog) or PTCH1 (Patched). We propose that BMP4 is a major gene for AM and/or retinal dystrophy and brain anomalies and may be a candidate gene for myopia and poly/syndactyly. Our finding of low-penetrant variants in BMP4 and HH signaling partners is suggestive of an interaction between the two pathways in humans.
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Affiliation(s)
- Preeti Bakrania
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX1 3QX, UK
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22
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Hever AM, Williamson KA, van Heyningen V. Developmental malformations of the eye: the role of PAX6, SOX2 and OTX2. Clin Genet 2007; 69:459-70. [PMID: 16712695 DOI: 10.1111/j.1399-0004.2006.00619.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Eye development initiates as an evagination of the early neural plate, before the closure of the neural tube. Structural malformations of the eye such as anophthalmia and microphthalmia arise very early in development. It is not surprising therefore that three of the genes currently identified to play a significant role in these developmental eye anomalies are also major players in brain development and regionalization. However, as has been emerging for a high proportion of transcriptional regulators studied, these genes have evolved to play multiple roles throughout development, and perhaps even in adult tissue maintenance. This complex spatiotemporal expression pattern requires elaborate regulatory systems which we are beginning to unravel. A major component of these complex regulatory networks is a series of cis-acting elements, highly conserved through evolution, which spread large distances from the coding region of each gene. We describe how cross regulation for PAX6, SOX2 and perhaps OTX2 has now been uncovered, pointing to the mechanisms that can fine-tune the expression of such essential developmental components. These interactions also help us understand why there is significant phenotypic overlap between mutations at these three loci.
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Affiliation(s)
- A M Hever
- MRC Human Genetics Unit, Western General Hospital, Edinburgh, UK
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23
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The level of BMP4 signaling is critical for the regulation of distinct T-box gene expression domains and growth along the dorso-ventral axis of the optic cup. BMC DEVELOPMENTAL BIOLOGY 2006; 6:62. [PMID: 17173667 PMCID: PMC1764729 DOI: 10.1186/1471-213x-6-62] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/03/2006] [Accepted: 12/15/2006] [Indexed: 12/30/2022]
Abstract
BACKGROUND Polarised gene expression is thought to lead to the graded distribution of signaling molecules providing a patterning mechanism across the embryonic eye. Bone morphogenetic protein 4 (Bmp4) is expressed in the dorsal optic vesicle as it transforms into the optic cup. Bmp4 deletions in human and mouse result in failure of eye development, but little attempt has been made to investigate mammalian targets of BMP4 signaling. In chick, retroviral gene overexpression studies indicate that Bmp4 activates the dorsally expressed Tbx5 gene, which represses ventrally expressed cVax. It is not known whether the Tbx5 related genes, Tbx2 and Tbx3, are BMP4 targets in the mammalian retina and whether BMP4 acts at a distance from its site of expression. Although it is established that Drosophila Dpp (homologue of vertebrate Bmp4) acts as a morphogen, there is little evidence that BMP4 gradients are interpreted to create domains of BMP4 target gene expression in the mouse. RESULTS Our data show that the level of BMP4 signaling is critical for the regulation of distinct Tbx2, Tbx3, Tbx5 and Vax2 gene expression domains along the dorso-ventral axis of the mouse optic cup. BMP4 signaling gradients were manipulated in whole mouse embryo cultures during optic cup development, by implantation of beads soaked in BMP4, or the BMP antagonist Noggin, to provide a local signaling source. Tbx2, Tbx3 and Tbx5, showed a differential response to alterations in the level of BMP4 along the entire dorso-ventral axis of the optic cup, suggesting that BMP4 acts across a distance. Increased levels of BMP4 caused expansion of Tbx2 and Tbx3, but not Tbx5, into the ventral retina and repression of the ventral marker Vax2. Conversely, Noggin abolished Tbx5 expression but only shifted Tbx2 expression dorsally. Increased levels of BMP4 signaling caused decreased proliferation, reduced retinal volume and altered the shape of the optic cup. CONCLUSION Our findings suggest the existence of a dorsal-high, ventral-low BMP4 signaling gradient across which distinct domains of Tbx2, Tbx3, Tbx5 and Vax2 transcription factor gene expression are set up. Furthermore we show that the correct level of BMP4 signaling is critical for normal growth of the mammalian embryonic eye.
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Abstract
The adenohypophysis and neurohypophysis originate from the combination of 2 events occurring during the fourth week of life, the development of Rathke pouch and of a neuroectodermal evagination of tissue from the floor of the diencephalon. Congenital pathology of the pituitary gland and parasellar regions derives from abnormalities of these coordinated events. In this article, we review the pathogenesis, clinical presentation, and imaging features of common and rare congenital disorders of the region of the sella turcica.
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Affiliation(s)
- M Vittoria Spampinato
- Department of Radiology, Medical University of South Carolina, Charleston, SC 29425, USA.
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25
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Nolen LD, Amor D, Haywood A, St Heaps L, Willcock C, Mihelec M, Tam P, Billson F, Grigg J, Peters G, Jamieson RV. Deletion at 14q22-23 indicates a contiguous gene syndrome comprising anophthalmia, pituitary hypoplasia, and ear anomalies. Am J Med Genet A 2006; 140:1711-8. [PMID: 16835935 DOI: 10.1002/ajmg.a.31335] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Anophthalmia and pituitary gland hypoplasia are both debilitating conditions where the underlying genetic defect is unknown in the majority of cases. We identified a patient with bilateral anophthalmia and absence of the optic nerves, chiasm and tracts, as well as pituitary gland hypoplasia and ear anomalies with a de novo apparently balanced chromosomal translocation, 46,XY,t(3;14)(q28;q23.2). Translocation breakpoint analysis using FISH and high-resolution microarray comparative genomic hybridization (CGH) has identified a 9.66 Mb deleted region on the long arm of chromosome 14 which includes the genes BMP4, OTX2, RTN1, SIX6, SIX1, and SIX4. Three other patients with interstitial deletions involving 14q22-23 have been described, all with bilateral anophthalmia, pituitary abnormalities, ear anomalies, and a facial phenotype similar to our patient. OTX2 is involved in ocular developmental defects, and the severity of the ocular phenotype in our patient and the other 14q22-23 deletion patients, suggests this genomic region harbors other gene/s involved in ocular development. BMP4 haploinsufficiency is predicted to contribute to the ocular phenotype on the basis of its expression pattern and observed murine mutant phenotypes. In addition, deletion of BMP4 and SIX6 is likely to contribute to the abnormal pituitary development, and SIX1 deletion may contribute to the ear and other craniofacial features. This indicates that contiguous gene deletion may contribute to the phenotypic features in the 14q22-23 deletion patients.
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Affiliation(s)
- Leisha D Nolen
- Eye Genetics Research Group, Children's Medical Research Institute, The Children's Hospital at Westmead and Save Sight Institute, Sydney, New South Wales, Australia
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26
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McConnell V, Derham R, McManus D, Morrison PJ. Mosaic monosomy 14: clinical features and recognizable facies. Clin Dysmorphol 2004; 13:155-160. [PMID: 15194951 DOI: 10.1097/01.mcd.0000126137.29572.59] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
A 1-year-old child with clinical features of monosomy 14 is reported. She has dysmorphic facial features including ocular colobomata, dolichocephaly and microcephaly, retinal pigmentation, severe seizures, fair curly hair and tapering fingers. There was severe mental retardation. This is the first reported case of severe mosaic monosomy 14, with up to 30% mosaicism. A recognizable facial gestalt is present in children with 14q deletions or partial monosomy 14, as well as susceptibility to infection, feeding difficulties, seizures and retinal pigmentation.
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Affiliation(s)
- V McConnell
- Department of Medical Genetics, Belfast City Hospital Trust, Belfast, UK Department of Obstetrics and Gynaecology, University College Galway, Galway, Ireland
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27
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Gallardo ME, Rodríguez De Córdoba S, Schneider AS, Dwyer MA, Ayuso C, Bovolenta P. Analysis of the developmentalSIX6homeobox gene in patients with anophthalmia/microphthalmia. Am J Med Genet A 2004; 129A:92-4. [PMID: 15266624 DOI: 10.1002/ajmg.a.30126] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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28
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Bacino CA. Re: Clinical report by Ahmad et al. 14q(22) deletion in a familial case of anophthalmia with polydactyly. ACTA ACUST UNITED AC 2004; 126A:109; author reply 110. [PMID: 15039983 DOI: 10.1002/ajmg.a.20522] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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29
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Ahmad ME, Dada R, Dada T, Kucheria K. 14q(22) deletion in a familial case of anophthalmia with polydactyly. Am J Med Genet A 2003; 120A:117-22. [PMID: 12794703 DOI: 10.1002/ajmg.a.10146] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
We report a family of anophthalmia with ocular and extraocular manifestations. The proband, his three sisters, and two sons had anophthalmia and preaxial polydactyly in the right hand. Cytogenetic analysis was done for the proband and two of his sons, one of whom was affected. Another male child was affected but was not available for cytogenetic analysis. Karyotypes of both affected individuals showed deletion on long arm of 14q22q23. Literature review shows four cases of anophthalmia with extra ocular anomalies associated with 14q (q22q23) deletion. Recently it has been suggested that the human homeobox gene, SIX6, and the BMP-4 gene are responsible for eye development. Both are located in the chromosome 14q22.3-q23 region. Deletion in this region has been known to be associated with anophthalmia and pituitary anomalies. This is the first family of anophthalmia, which showed polydactyly with a chromosomal deletion in the 14q22-q23 region and its familial transmission in two generations with a total of six affected individuals.
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Affiliation(s)
- M E Ahmad
- Genetics Division, Department of Anatomy, All India Institute of Medical Sciences, New Delhi 110029, India
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Laclef C, Souil E, Demignon J, Maire P. Thymus, kidney and craniofacial abnormalities in Six 1 deficient mice. Mech Dev 2003; 120:669-79. [PMID: 12834866 DOI: 10.1016/s0925-4773(03)00065-0] [Citation(s) in RCA: 168] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Six genes are widely expressed during vertebrate embryogenesis, suggesting that they are implicated in diverse differentiation processes. To determine the functions of the Six1 gene, we constructed Six1-deficient mice by replacing its first exon by the beta-galactosidase gene. We have previously shown that mice lacking Six1 die at birth due to thoracic skeletal defects and severe muscle hypoplasia affecting most of the body muscles. Here, we report that Six1(-/-) neonates also lack a kidney and thymus, as well as displaying a strong disorganisation of craniofacial structures, namely the inner ear, the nasal cavity, the craniofacial skeleton, and the lacrimal and parotid glands. These organ defects can be correlated with Six1 expression in the embryonic primordium structures as revealed by X-Gal staining at different stages of embryogenesis. Thus, the fetal abnormalities of Six1(-/-) mice appear to result from the absence of the Six 1 homeoprotein during early stages of organogenesis. Interestingly, these Six1 defects are very similar to phenotypes caused by mutations of Eya 1, which are responsible for the BOR syndrome in humans. Close comparison of Six1 and Eya 1 deficient mice strongly suggests a functional link between these two factors. Pax gene mutations also lead to comparable phenotypes, suggesting that a regulatory network including the Pax, Six and Eya genes is required for several types of organogenesis in mammals.
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Affiliation(s)
- Christine Laclef
- Département Génétique, Développement et Pathologie Moléculaire, Université Paris V, 24 Rue du Faubourg Saint Jacques, 75014 Paris, France
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31
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Hoover-Fong JE, Cai J, Cargile CB, Thomas GH, Patel A, Griffin CA, Jabs EW, Hamosh A. Facial dysgenesis: a novel facial syndrome with chromosome 7 deletion p15.1-21.1. Am J Med Genet A 2003; 117A:47-56. [PMID: 12548740 DOI: 10.1002/ajmg.a.10046] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
We describe a female neonate with a unique constellation of features including anophthalmia and cryptophthalmos, temporal remnant "eye tags," bilateral cleft lip, unilateral cleft palate, a proboscis with absent nasal septum, choanal atresia, micrognathia, square stoma, and bilateral external auditory canal atresia. Gross brain structure, pituitary function, limbs, trunk, and genitalia were normal. Skeletal survey, echocardiogram and abdominal viscera were unremarkable except for a split central sinus of the right kidney. BAER exam indicated she could hear and temporal CT confirmed the presence of cochlea and possible ossicles. Cytogenetic evaluation revealed an interstitial deletion at chromosome 7p15.1-21.1. TWIST, a gene encoding a transcription factor involved in craniofacial development, is deleted by FISH analysis. The absence of a mutation on the non-deleted allele of TWIST as determined by sequencing virtually eliminates complete loss of the TWIST gene as the cause of this patient's severe phenotype. The HOXA gene cluster also encodes transcription factors that are crucial for directing cephalad to caudad somatic fetal development. HOXA1, the most telomeric of the 13 members of the HOXA gene cluster, is located at the centromeric boundary of the patient's chromosome 7 deletion. By FISH analysis, neither allele of HOXA1 is deleted and sequencing reveals no mutations. Haploinsufficiency or complete loss of the HOXA1 gene also does not appear to cause this patient's severe phenotype. Previous reports of chromosome 7p15-21 deletions do not have phenotypes similar to this patient.
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Affiliation(s)
- Julie E Hoover-Fong
- McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University, Baltimore, Maryland 21287, USA.
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Szavay PO, Schliephake H, Hubert O, Glüer S. Colon atresia, facial hemiaplasia, and anophthalmia: a case report. J Pediatr Surg 2002; 37:1498-500. [PMID: 12378467 DOI: 10.1053/jpsu.2002.35431] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A case of a newborn with atresia of the transverse colon and right facial hemiaplasia, anophthalmia, and cerebral dysfunction is reported. Colon atresia is a rare cause of congenital bowel obstruction and often associated with other malformations such as abdominal wall defects, gastrointestinal, cardiac, urogenital, and musculosceletal lesions. Facial hemiaplasia may arise in frame of chromosomal defects or as a result of neurovascular compromise caused by congenital amniotic bands. However, the combination of colon atresia and facial hemiaplasia has not been reported before.
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Affiliation(s)
- Philipp O Szavay
- Department of Pediatric Surgery, Medical School Hannover, Hannover, Germany
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Rauchman M, Hoffman WH, Hanna JD, Kulharya AS, Figueroa RE, Yang J, Tuck-Miller CM. Exclusion of SIX6 hemizygosity in a child with anophthalmia, panhypopituitarism and renal failure. AMERICAN JOURNAL OF MEDICAL GENETICS 2001; 104:31-6. [PMID: 11746024 DOI: 10.1002/ajmg.10016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We report a patient who presented with anophthalmia, panhypopituitarism, early onset of end stage renal failure, and craniofacial abnormalities. MRI at age 3 revealed that the pituitary was absent and renal biopsy demonstrated nephronophthisis as the cause of the renal failure. A similar syndrome has been associated with interstitial deletions of chromosome 14q22 and in one case hemizygosity for SIX6 was demonstrated. The patient reported here had a normal karyotype and Southern blot did not reveal loss of one copy of SIX6. We discuss other possible candidate genes that could be implicated in this syndrome.
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Affiliation(s)
- M Rauchman
- Renal Division, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, MO 63110, USA.
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Sutton VR, Shaffer LG. Search for imprinted regions on chromosome 14: comparison of maternal and paternal UPD cases with cases of chromosome 14 deletion. AMERICAN JOURNAL OF MEDICAL GENETICS 2000; 93:381-7. [PMID: 10951461 DOI: 10.1002/1096-8628(20000828)93:5<381::aid-ajmg7>3.0.co;2-9] [Citation(s) in RCA: 92] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Over the past few years, regions of genomic imprinting have been identified on a small number of chromosomes through a search for the etiology of various disorders. Distinct phenotypes have been associated with both maternal and paternal uniparental disomy (UPD) for chromosome 14. This observation indicates that there are imprinted genes present on chromosome 14, although none have been identified to date. In order to focus the search for imprinted genes on chromosome 14, we analyzed cases of maternal and paternal UPD 14 and compared them with cases of chromosome 14 deletions. Cases of paternal UPD were compared with maternal deletions and maternal UPD compared with paternal deletions. The paternal UPD anomalies seen in maternal deletion cases allowed us to associate the following features and chromosomal regions: Hirsute forehead: del(14)(q12q13. 3) and del(14)(q32); blepharophimosis: del(14)(q32); small thorax: del(14)(q11.2q13); and joint contractures: del(14)(q11.2q13) and del(14)(q31). Comparison of maternal UPD and paternal deletion cases revealed fleshy nasal tip to be most often associated with del(14)(q32), scoliosis with del(14) (q23q24.2), and del(14)(q32. 11qter) and small size at birth to be associated with del(14)(q11q13) and del(14)(q32). Our study, in conjunction with a prior study of UPD 14 and partial trisomy 14 cases, and what is known of imprinting in regions of mouse chromosomes homologous to human chromosome 14, leads us to conclude that 14q23-q32 is likely an area where imprinted genes may reside.
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Affiliation(s)
- V R Sutton
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.
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Abstract
The pituitary gland, the "master gland" of the body, is composed of endocrine cells, which secrete hormones essential for homeostasis. The gland consists of the adenohypophysis (anterior pituitary) and the neurohypophysis (posterior pituitary), two unique structures that differ anatomically and functionally. The neurohypophysis is innervated by nerve cells in the hypothalamus and forms the connection between it and the pituitary gland. The hypothalamus stimulates release and inhibition of pituitary hormones. The neurohypophysis secretes oxytocin and antidiuretic hormone. The adenohypophysis is composed of three structures: the pars distalis, the pars intermedia, and the pars tuberalis. The anterior pituitary (pars distalis) is responsible for the release of hormones that include growth hormone, prolactin, thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone, adrenocorticotropic hormone, and melanocyte-stimulating hormone. Disorders of the pituitary are predominately those of insufficient hormone release and may have profound effects on the neonate. The potential causes of and clinical symptomatology that may accompany pituitary hormone insufficiency in the neonatal period are explored.
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Affiliation(s)
- A M Dorton
- Rush University College of Nursing, Armour Academic Center, Suite 1022, 600 S. Paulina Street, Chicago, IL 60612-3832, USA.
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Gallardo ME, Lopez-Rios J, Fernaud-Espinosa I, Granadino B, Sanz R, Ramos C, Ayuso C, Seller MJ, Brunner HG, Bovolenta P, Rodríguez de Córdoba S. Genomic cloning and characterization of the human homeobox gene SIX6 reveals a cluster of SIX genes in chromosome 14 and associates SIX6 hemizygosity with bilateral anophthalmia and pituitary anomalies. Genomics 1999; 61:82-91. [PMID: 10512683 DOI: 10.1006/geno.1999.5916] [Citation(s) in RCA: 111] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Drosophila gene sine oculis (so), a nuclear homeoprotein that is required for eye development, has several homologues in vertebrates (the SIX gene family). Among them, SIX3 is considered to be the functional orthologue of so because it is strongly expressed in the developing eye. However, embryonic SIX3 expression is not limited to the eye field, and SIX3 has been found to be mutated in some patients with holoprosencephaly type 2 (HPE2), suggesting that SIX3 has wide implications in head development. We report here the cloning and characterization of SIX6, a novel human SIX gene that is the homologue of the chick Six6(Optx2) gene. SIX6 is closely related to SIX3 and is expressed in the developing and adult human retina. Data from chick and mouse suggest that the human SIX6 gene is also expressed in the hypothalamic and the pituitary regions. SIX6 spans 2567 bp of genomic DNA and is split in two exons that are transcribed into a 1393-nucleotide-long mRNA. Chromosomal mapping of SIX6 revealed that it is closely linked to SIX1 and SIX4 in human chromosome 14q22.3-q23, which provides clues about the origin and evolution of the vertebrate SIX family. Recently three independent reports have associated interstitial deletions at 14q22.3-q23 with bilateral anophthalmia and pituitary anomalies. Genomic analyses of one of these cases demonstrated SIX6 hemizygosity, strongly suggesting that SIX6 haploinsufficiency is responsible for these developmental disorders.
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Affiliation(s)
- M E Gallardo
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Científicas, Velázquez 144, Madrid, 28006, Spain
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Sankaranarayanan K. Ionizing radiation and genetic risks. X. The potential "disease phenotypes" of radiation-induced genetic damage in humans: perspectives from human molecular biology and radiation genetics. Mutat Res 1999; 429:45-83. [PMID: 10434024 DOI: 10.1016/s0027-5107(99)00100-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Estimates of genetic risks of radiation exposure of humans are traditionally expressed as expected increases in the frequencies of genetic diseases (single-gene, chromosomal and multifactorial) over and above those of naturally-occurring ones in the population. An important assumption in expressing risks in this manner is that gonadal radiation exposures can cause an increase in the frequency of mutations and that this would result in an increase in the frequency of genetic diseases under study. However, despite compelling evidence for radiation-induced mutations in experimental systems, no increases in the frequencies of genetic diseases of concern or other adverse effects (i.e., those which are not formally classified as genetic diseases), have been found in human studies involving parents who have sustained radiation exposures. The known differences between spontaneous mutations that underlie naturally-occurring single-gene diseases and radiation-induced mutations studied in experimental systems now permit us to address and resolve these issues to some extent. The fact that spontaneous mutations (among which are point mutations and DNA deletions generally restricted to the gene) originate through a number of different mechanisms and that the latter are intimately related to the DNA organization of the genes, are now well-documented. Further, spontaneous mutations include those that cause diseases through loss of function as well as gain of function of genes. In contrast, most radiation-induced mutations studied in experimental systems (although identified through the phenotypes of the marker genes) are predominantly multigene deletions which cause loss of function; the recoverability of an induced deletion in a livebirth seems dependent on whether the gene and the genomic region in which it is located can tolerate heterozygosity for the deletion and yet be compatible with viability. In retrospect, the successful mutation test systems (such as the mouse specific locus test) used in radiation studies have involved genes which are non-essential for survival and are also located in genomic regions, likewise non-essential for survival. In contrast, most of the human genes at which induced mutations have been looked for, do not seem to have these attributes. The inference therefore is that the failure to find induced germline mutations in humans is not due to the resistance of human genes to induced mutations but due to the structural and functional constraints associated with their recoverability in livebirths. Since the risk of inducible genetic diseases in humans is estimated using rates of "recovered" mutations in mice, there is a need to introduce appropriate correction factors to bridge the gap between these rates and the rates at which mutations causing diseases are potentially recoverable in humans. Since the whole genome is the "target" for radiation-induced genetic damage, the failure to find increases in the frequencies of specific single-gene diseases of societal concern does not imply that there are no genetic risks of radiation exposures: the problem lies in delineating the phenotypes of recoverable genetic damage that are recognizable in livebirths. Data from studies of naturally-occurring microdeletion syndromes in humans and those from mouse radiation studies are instructive in this regard. They (i) support the view that growth retardation, mental retardation and multisystem developmental abnormalities are likely to be among the quantitatively more important adverse effects of radiation-induced genetic damage than mutations in a few selected genes and (ii) underscore the need to expand the focus in risk estimation from known genetic diseases (as has been the case thus far) to include these induced adverse developmental effects although most of these are not formally classified as "genetic diseases". (ABSTRACT TRUNCATED)
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Affiliation(s)
- K Sankaranarayanan
- MGC, Department of Radiation Genetics and Chemical Mutagenesis, Leiden University Medical Centre, Sylvius Laboratories, Wassenaarseweg 72, 2333 AL, Leiden, Netherlands.
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