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Gour A, Tibrewal S, Garg A, Vohra M, Ratna R, Sangwan VS. New horizons in aniridia management: Clinical insights and therapeutic advances. Taiwan J Ophthalmol 2023; 13:467-478. [PMID: 38249501 PMCID: PMC10798387 DOI: 10.4103/tjo.tjo-d-23-00140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 10/11/2023] [Indexed: 01/23/2024] Open
Abstract
Congenital aniridia is a rare genetic eye disorder characterized by the complete or partial absence of the iris from birth. Various theories and animal models have been proposed to understand and explain the pathogenesis of aniridia. In the majority of cases, aniridia is caused by a mutation in the PAX6 gene, which affects multiple structures within the eye. Treating these ocular complications is challenging and carries a high risk of side effects. However, emerging approaches for the treatment of aniridia-associated keratopathy, iris abnormalities, cataract abnormalities, and foveal hypoplasia show promise for improved outcomes. Genetic counseling plays a very important role to make informed choices. We also provide an overview of the newer diagnostic and therapeutic approaches such as next generation sequencing, gene therapy, in vivo silencing, and miRNA modulation.
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Affiliation(s)
- Abha Gour
- Department of Cornea and Anterior Segment, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
- Eicher-Shroff Centre for Stem Cell Research, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
| | - Shailaja Tibrewal
- Department of Pediatric Ophthalmology and Strabismus, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
- Department of Ocular Genetics, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
| | - Aastha Garg
- Department of Cornea and Anterior Segment, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
| | - Mehak Vohra
- Eicher-Shroff Centre for Stem Cell Research, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
| | - Ria Ratna
- Department of Ocular Genetics, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
| | - Virender Singh Sangwan
- Department of Cornea and Anterior Segment, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
- Eicher-Shroff Centre for Stem Cell Research, Dr. Shroff’s Charity Eye Hospital, New Delhi, India
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2
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Daruich A, Duncan M, Robert MP, Lagali N, Semina EV, Aberdam D, Ferrari S, Romano V, des Roziers CB, Benkortebi R, De Vergnes N, Polak M, Chiambaretta F, Nischal KK, Behar-Cohen F, Valleix S, Bremond-Gignac D. Congenital aniridia beyond black eyes: From phenotype and novel genetic mechanisms to innovative therapeutic approaches. Prog Retin Eye Res 2023; 95:101133. [PMID: 36280537 PMCID: PMC11062406 DOI: 10.1016/j.preteyeres.2022.101133] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2022] [Revised: 09/27/2022] [Accepted: 10/03/2022] [Indexed: 11/05/2022]
Abstract
Congenital PAX6-aniridia, initially characterized by the absence of the iris, has progressively been shown to be associated with other developmental ocular abnormalities and systemic features making congenital aniridia a complex syndromic disorder rather than a simple isolated disease of the iris. Moreover, foveal hypoplasia is now recognized as a more frequent feature than complete iris hypoplasia and a major visual prognosis determinant, reversing the classical clinical picture of this disease. Conversely, iris malformation is also a feature of various anterior segment dysgenesis disorders caused by PAX6-related developmental genes, adding a level of genetic complexity for accurate molecular diagnosis of aniridia. Therefore, the clinical recognition and differential genetic diagnosis of PAX6-related aniridia has been revealed to be much more challenging than initially thought, and still remains under-investigated. Here, we update specific clinical features of aniridia, with emphasis on their genotype correlations, as well as provide new knowledge regarding the PAX6 gene and its mutational spectrum, and highlight the beneficial utility of clinically implementing targeted Next-Generation Sequencing combined with Whole-Genome Sequencing to increase the genetic diagnostic yield of aniridia. We also present new molecular mechanisms underlying aniridia and aniridia-like phenotypes. Finally, we discuss the appropriate medical and surgical management of aniridic eyes, as well as innovative therapeutic options. Altogether, these combined clinical-genetic approaches will help to accelerate time to diagnosis, provide better determination of the disease prognosis and management, and confirm eligibility for future clinical trials or genetic-specific therapies.
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Affiliation(s)
- Alejandra Daruich
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France; INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France
| | - Melinda Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE, USA
| | - Matthieu P Robert
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France; Borelli Centre, UMR 9010, CNRS-SSA-ENS Paris Saclay-Paris Cité University, Paris, France
| | - Neil Lagali
- Division of Ophthalmology, Department of Biomedical and Clinical Sciences, Faculty of Medicine, Linköping University, 581 83, Linköping, Sweden; Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway
| | - Elena V Semina
- Department of Pediatrics, Children's Research Institute at the Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI, 53226, USA
| | - Daniel Aberdam
- INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France
| | - Stefano Ferrari
- Fondazione Banca degli Occhi del Veneto, Via Paccagnella 11, Venice, Italy
| | - Vito Romano
- Department of Medical and Surgical Specialties, Radiolological Sciences, and Public Health, Ophthalmology Clinic, University of Brescia, Italy
| | - Cyril Burin des Roziers
- INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France; Service de Médecine Génomique des Maladies de Système et d'Organe, APHP. Centre Université de Paris, Fédération de Génétique et de Médecine Génomique Hôpital Cochin, 27 rue du Fbg St-Jacques, 75679, Paris Cedex 14, France
| | - Rabia Benkortebi
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France
| | - Nathalie De Vergnes
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France
| | - Michel Polak
- Pediatric Endocrinology, Gynecology and Diabetology, Hôpital Universitaire Necker Enfants Malades, AP-HP, Paris Cité University, INSERM U1016, Institut IMAGINE, France
| | | | - Ken K Nischal
- Division of Pediatric Ophthalmology, Strabismus, and Adult Motility, UPMC Children's Hospital of Pittsburgh, Pittsburgh, PA, USA; UPMC Eye Center, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - Francine Behar-Cohen
- INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France
| | - Sophie Valleix
- INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France; Service de Médecine Génomique des Maladies de Système et d'Organe, APHP. Centre Université de Paris, Fédération de Génétique et de Médecine Génomique Hôpital Cochin, 27 rue du Fbg St-Jacques, 75679, Paris Cedex 14, France
| | - Dominique Bremond-Gignac
- Ophthalmology Department, Necker-Enfants Malades University Hospital, AP-HP, Paris Cité University, Paris, France; INSERM, UMRS1138, Team 17, From Physiopathology of Ocular Diseases to Clinical Development, Sorbonne Paris Cité University, Centre de Recherche des Cordeliers, Paris, France.
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3
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Landsend ECS, Lagali N, Utheim TP. Congenital aniridia - A comprehensive review of clinical features and therapeutic approaches. Surv Ophthalmol 2021; 66:1031-1050. [PMID: 33675823 DOI: 10.1016/j.survophthal.2021.02.011] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2020] [Revised: 02/16/2021] [Accepted: 02/23/2021] [Indexed: 12/13/2022]
Abstract
Congenital aniridia is a rare genetic eye disorder with total or partial absence of the iris from birth. In most cases the genetic origin of aniridia is a mutation in the PAX6 gene, leading to involvement of most eye structures. Hypoplasia of the fovea is usually present and is associated with reduced visual acuity and nystagmus. Aniridia-associated keratopathy, glaucoma, and cataract are serious and progressive complications that can further reduce visual function. Treatment of the ocular complications of aniridia is challenging and has a high risk of side effects. New approaches such as stem cell therapy may, however, offer better prognoses. We describe the various ocular manifestations of aniridia, with a special focus on conditions that commonly require treatment. We also review the growing literature reporting systemic manifestations of the disease.
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Affiliation(s)
| | - Neil Lagali
- Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden
| | - Tor P Utheim
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway; Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
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4
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Grant MK, Bobilev AM, Branch A, Lauderdale JD. Structural and functional consequences of PAX6 mutations in the brain: Implications for aniridia. Brain Res 2021; 1756:147283. [PMID: 33515537 DOI: 10.1016/j.brainres.2021.147283] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 12/15/2020] [Accepted: 01/05/2021] [Indexed: 12/27/2022]
Abstract
The paired-box 6 (PAX6) gene encodes a highly conserved transcription factor essential for the proper development of the eye and brain. Heterozygous loss-of-function mutations in PAX6 are causal for a condition known as aniridia in humans and the Small eye phenotype in mice. Aniridia is characterized by iris hypoplasia and other ocular abnormalities, but recent evidence of neuroanatomical, sensory, and cognitive impairments in this population has emerged, indicating brain-related phenotypes as a prevalent feature of the disorder. Determining the neurophysiological origins of brain-related phenotypes in this disorder presents a substantial challenge, as the majority of extra-ocular traits in aniridia demonstrate a high degree of heterogeneity. Here, we summarize and integrate findings from human and rodent model studies, which have focused on neuroanatomical and functional consequences of PAX6 mutations. We highlight novel findings from PAX6 central nervous system studies in adult mammals, and integrate these findings into what we know about PAX6's role in development of the central nervous system. This review presents the current literature in the field in order to inform clinical application, discusses what is needed in future studies, and highlights PAX6 as a lens through which to understand genetic disorders affecting the human nervous system.
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Affiliation(s)
- Madison K Grant
- Department of Cellular Biology, The University of Georgia, Athens, GA 30602, USA.
| | - Anastasia M Bobilev
- Neuroscience Division of the Biomedical and Health Sciences Institute, The University of Georgia, Athens, GA 30602, USA; Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Audrey Branch
- Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21218, USA.
| | - James D Lauderdale
- Department of Cellular Biology, The University of Georgia, Athens, GA 30602, USA; Neuroscience Division of the Biomedical and Health Sciences Institute, The University of Georgia, Athens, GA 30602, USA.
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5
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Cole JD, Rodriguez C, Norat P, Gao J, Provencio I, Netland PA, Liu X. Neural damage and neuroprotection with glaucoma development in aniridia. CURRENT NEUROBIOLOGY 2021; 12:14-19. [PMID: 38125639 PMCID: PMC10732493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Affiliation(s)
- James D Cole
- Department of Biology, University of Virginia, Charlottesville, VA, USA
- Neuroscience Graduate Program, University of Virginia, Charlottesville, VA, USA
| | - Carlos Rodriguez
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Pedro Norat
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Jingyi Gao
- Department of Biology, University of Virginia, Charlottesville, VA, USA
| | - Ignacio Provencio
- Department of Biology, University of Virginia, Charlottesville, VA, USA
- Department of Ophthalmology, University of Virginia, Charlottesville, VA, USA
| | - Peter A Netland
- Department of Ophthalmology, University of Virginia, Charlottesville, VA, USA
| | - Xiaorong Liu
- Department of Biology, University of Virginia, Charlottesville, VA, USA
- Department of Ophthalmology, University of Virginia, Charlottesville, VA, USA
- Department of Psychology, University of Virginia, Charlottesville, VA, USA
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6
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Grant MK, Bobilev AM, Rasys AM, Branson Byers J, Schriever HC, Hekmatyar K, Lauderdale JD. Global and age-related neuroanatomical abnormalities in a Pax6-deficient mouse model of aniridia suggests a role for Pax6 in adult structural neuroplasticity. Brain Res 2020; 1732:146698. [PMID: 32014531 PMCID: PMC10712278 DOI: 10.1016/j.brainres.2020.146698] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/14/2020] [Accepted: 01/30/2020] [Indexed: 12/29/2022]
Abstract
PAX6 encodes a highly conserved transcription factor necessary for normal development of the eyes and central nervous system. Heterozygous loss-of-function mutations in PAX6 cause the disorder aniridia in humans and the Small eye trait in mice. Aniridia is a congenital and progressive disorder known for ocular phenotypes; however, recently, consequences of PAX6 haploinsufficiency in the brains of aniridia patients have been identified. These findings span structural and functional abnormalities, including deficits in cognitive and sensory processing. Furthermore, some of these abnormalities are accelerated as aniridia patients age. Although some functional abnormalities may be explained by structural changes, variability of results remain, and the effects of PAX6 heterozygous loss-of-function mutations on neuroanatomy, particularly with regard to aging, have yet to be resolved. Our study used high-resolution magnetic resonance imaging (MRI) and histology to investigate structural consequences of such mutations in the adult brain of our aniridia mouse model, Small eye Neuherberg allele (Pax6SeyNeu/+), at two adult age groups. Using both MRI and histology enables a direct comparison with human studies, while providing higher resolution for detection of more subtle changes. We show volumetric changes in major brain regions of the the Pax6SeyNeu/+ mouse compared to wild-type including genotype- and age-related olfactory bulb differences, age-related cerebellum differences, and genotype-related eye differences. We also show alterations in thickness of major interhemispheric commissures, particularly those anteriorly located within the brain including the optic chiasm, corpus callosum, and anterior commissure. Together, these genotype and age related changes to brain volumes and structures suggest a global decrease in adult brain structural plasticity in our Pax6SeyNeu/+ mice.
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Affiliation(s)
- Madison K Grant
- Department of Cellular Biology, University of Georgia, 250B Coverdell Center, 500 D.W. Brooks Drive, Athens, GA 30602, United States.
| | - Anastasia M Bobilev
- Department of Psychiatry, UT Southwestern Medical Center, 5323 Harry Hines Blvd., Dallas, TX, United States; Neuroscience Division of the Biomedical and Health Sciences Institute, The University of Georgia, Athens, GA 30602, United States.
| | - Ashley M Rasys
- Department of Cellular Biology, University of Georgia, 250B Coverdell Center, 500 D.W. Brooks Drive, Athens, GA 30602, United States.
| | - J Branson Byers
- Department of Cellular Biology, University of Georgia, 250B Coverdell Center, 500 D.W. Brooks Drive, Athens, GA 30602, United States.
| | - Hannah C Schriever
- Department of Cellular Biology, University of Georgia, 250B Coverdell Center, 500 D.W. Brooks Drive, Athens, GA 30602, United States.
| | - Khan Hekmatyar
- Bio-imaging Research Center, University of Georgia, Coverdell Center, 500 D.W. Brooks Drive, Athens, GA 30602, United States.
| | - James D Lauderdale
- Department of Cellular Biology, University of Georgia, 250B Coverdell Center, 500 D.W. Brooks Drive, Athens, GA 30602, United States; Neuroscience Division of the Biomedical and Health Sciences Institute, The University of Georgia, Athens, GA 30602, United States.
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Bobilev AM, Hudgens-Haney ME, Hamm JP, Oliver WT, McDowell JE, Lauderdale JD, Clementz BA. Early and late auditory information processing show opposing deviations in aniridia. Brain Res 2019; 1720:146307. [PMID: 31247203 DOI: 10.1016/j.brainres.2019.146307] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2018] [Revised: 06/12/2019] [Accepted: 06/23/2019] [Indexed: 01/29/2023]
Abstract
Aniridia is a congenital disorder, predominantly caused by heterozygous mutations of the PAX6 gene. While ocular defects have been extensively characterized in this population, brain-related anatomical and functional abnormalities are emerging as a prominent feature of the disorder. Individuals with aniridia frequently exhibit auditory processing deficits despite normal audiograms. While previous studies have reported hypoplasia of the anterior commissure and corpus callosum in some of these individuals, the neurophysiological basis of these impairments remains unexplored. This study provides direct assessment of neural activity related to auditory processing in aniridia. Participants were presented with tones designed to elicit an auditory steady-state response (ASSR) at 22 Hz, 40 Hz, and 84 Hz, and infrequent broadband target tones to maintain attention during electroencephalography (EEG) recording. Persons with aniridia showed increased early cortical responses (P50 AEP) in response to all tones, and increased high-frequency oscillatory entrainment (84 Hz ASSR). In contrast, this group showed a decreased cortical integration response (P300 AEP to target tones) and reduced neural entrainment to cortical beta-band stimuli (22 Hz ASSR). Collectively, our results suggest that subcortical and early cortical auditory processing is augmented in aniridia, while functional cortical integration of auditory information is deficient in this population.
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Affiliation(s)
- Anastasia M Bobilev
- Department of Cellular Biology, Bio-Imaging Research Center, University of Georgia, Athens, GA, United States; Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX, United States.
| | - Matthew E Hudgens-Haney
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX, United States; Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, United States
| | - Jordan P Hamm
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, United States; Neuroscience Institute, Georgia State University, Petit Science Center, Atlanta, GA, United States; Center for Neuroinflammation and Cardiometabolic Diseases, Georgia State University, Petit Science Center, Atlanta, GA, United States
| | - William T Oliver
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, United States
| | - Jennifer E McDowell
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, United States
| | - James D Lauderdale
- Department of Cellular Biology, Bio-Imaging Research Center, University of Georgia, Athens, GA, United States
| | - Brett A Clementz
- Departments of Psychology and Neuroscience, Bio-Imaging Research Center, University of Georgia, Athens, GA, United States
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8
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Microstructural differences in visual white matter tracts in people with aniridia. Neuroreport 2018; 29:1473-1478. [DOI: 10.1097/wnr.0000000000001135] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Zic4-Lineage Cells Increase Their Contribution to Visual Thalamic Nuclei during Murine Embryogenesis If They Are Homozygous or Heterozygous for Loss of Pax6 Function. eNeuro 2018; 5:eN-CFN-0367-18. [PMID: 30406191 PMCID: PMC6220585 DOI: 10.1523/eneuro.0367-18.2018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 09/22/2018] [Indexed: 12/22/2022] Open
Abstract
Our aim was to study the mechanisms that contribute to the development of discrete thalamic nuclei during mouse embryogenesis (both sexes included). We characterized the expression of the transcription factor coding gene Zic4 and the distribution of cells that expressed Zic4 in their lineage. We used genetic fate mapping to show that Zic4-lineage cells mainly contribute to a subset of thalamic nuclei, in particular the lateral geniculate nuclei (LGNs), which are crucial components of the visual pathway. We observed that almost all Zic4-lineage diencephalic progenitors express the transcription factor Pax6 at variable location-dependent levels. We used conditional mutagenesis to delete either one or both copies of Pax6 from Zic4-lineage cells. We found that Zic4-lineage cells carrying either homozygous or heterozygous loss of Pax6 contributed in abnormally high numbers to one or both of the main lateral geniculate nuclei (LGNs). This could not be attributed to a change in cell production and was likely due to altered sorting of thalamic cells. Our results indicate that positional information encoded by the levels of Pax6 in diencephalic progenitors is an important determinant of the eventual locations of their daughter cells.
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Grant MK, Bobilev AM, Pierce JE, DeWitte J, Lauderdale JD. Structural brain abnormalities in 12 persons with aniridia. F1000Res 2017; 6:255. [PMID: 29034075 PMCID: PMC5615777 DOI: 10.12688/f1000research.11063.2] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/27/2017] [Indexed: 02/04/2023] Open
Abstract
Background: Aniridia is a disorder predominately caused by heterozygous loss-of-function mutations of the
PAX6 gene, which is a transcriptional regulator necessary for normal eye and brain development. The ocular abnormalities of aniridia have been well characterized, but mounting evidence has implicated brain-related phenotypes as a prominent feature of this disorder as well. Investigations using neuroimaging in aniridia patients have shown reductions in discrete brain structures and changes in global grey and white matter. However, limited sample sizes and substantive heterogeneity of structural phenotypes in the brain remain a challenge.
Methods: Here, we examined brain structure in a new population sample in an effort to add to the collective understanding of anatomical abnormalities in aniridia. The current study used 3T magnetic resonance imaging to acquire high-resolution structural data in 12 persons with aniridia and 12 healthy demographically matched comparison subjects.
Results: We examined five major structures: the anterior commissure, the posterior commissure, the pineal gland, the corpus callosum, and the optic chiasm. The most consistent reductions were found in the anterior commissure and the pineal gland; however, abnormalities in all of the other structures examined were present in at least one individual.
Conclusions: Our results indicate that the anatomical abnormalities in aniridia are variable and largely individual-specific. These findings suggest that future studies investigate this heterogeneity further, and that normal population variation should be considered when evaluating structural abnormalities.
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Affiliation(s)
- Madison K Grant
- Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA
| | - Anastasia M Bobilev
- Neuroscience Division of the Biomedical and Health Sciences Institute, University of Georgia, Athens, GA, 30602, USA
| | - Jordan E Pierce
- Department of Psychology, University of Georgia, Athens, GA, 30602, USA
| | - Jon DeWitte
- Athens Radiology Associates, Athens, GA, 30604, USA
| | - James D Lauderdale
- Department of Cellular Biology, University of Georgia, Athens, GA, 30602, USA.,Neuroscience Division of the Biomedical and Health Sciences Institute, University of Georgia, Athens, GA, 30602, USA
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11
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Yoshizaki K, Furuse T, Kimura R, Tucci V, Kaneda H, Wakana S, Osumi N. Paternal Aging Affects Behavior in Pax6 Mutant Mice: A Gene/Environment Interaction in Understanding Neurodevelopmental Disorders. PLoS One 2016; 11:e0166665. [PMID: 27855195 PMCID: PMC5113965 DOI: 10.1371/journal.pone.0166665] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2016] [Accepted: 11/01/2016] [Indexed: 12/26/2022] Open
Abstract
Neurodevelopmental disorders such as autism spectrum disorder (ASD) and attention deficit and hyperactivity disorder (ADHD) have increased over the last few decades. These neurodevelopmental disorders are characterized by a complex etiology, which involves multiple genes and gene-environmental interactions. Various genes that control specific properties of neural development exert pivotal roles in the occurrence and severity of phenotypes associated with neurodevelopmental disorders. Moreover, paternal aging has been reported as one of the factors that contribute to the risk of ASD and ADHD. Here we report, for the first time, that paternal aging has profound effects on the onset of behavioral abnormalities in mice carrying a mutation of Pax6, a gene with neurodevelopmental regulatory functions. We adopted an in vitro fertilization approach to restrict the influence of additional factors. Comprehensive behavioral analyses were performed in Sey/+ mice (i.e., Pax6 mutant heterozygotes) born from in vitro fertilization of sperm taken from young or aged Sey/+ fathers. No body weight changes were found in the four groups, i.e., Sey/+ and wild type (WT) mice born to young or aged father. However, we found important differences in maternal separation-induced ultrasonic vocalizations of Sey/+ mice born from young father and in the level of hyperactivity of Sey/+ mice born from aged fathers in the open-field test, respectively, compared to WT littermates. Phenotypes of anxiety were observed in both genotypes born from aged fathers compared with those born from young fathers. No significant difference was found in social behavior and sensorimotor gating among the four groups. These results indicate that mice with a single genetic risk factor can develop different phenotypes depending on the paternal age. Our study advocates for serious considerations on the role of paternal aging in breeding strategies for animal studies.
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Affiliation(s)
- Kaichi Yoshizaki
- Department of Developmental Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Tamio Furuse
- Technology and Development Team for Mouse Phenotype Analysis, The Japan Mouse Clinic, RIKEN BRC, Tsukuba, Ibaraki, Japan
| | - Ryuichi Kimura
- Department of Developmental Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Valter Tucci
- Department of Neuroscience and Brain Technologies. Istituto Italiano di Tecnologia, Genova, Italy
| | - Hideki Kaneda
- Technology and Development Team for Mouse Phenotype Analysis, The Japan Mouse Clinic, RIKEN BRC, Tsukuba, Ibaraki, Japan
| | - Shigeharu Wakana
- Technology and Development Team for Mouse Phenotype Analysis, The Japan Mouse Clinic, RIKEN BRC, Tsukuba, Ibaraki, Japan
| | - Noriko Osumi
- Department of Developmental Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- * E-mail:
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