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Harding P, Gore S, Malka S, Rajkumar J, Oluonye N, Moosajee M. Real-world clinical and molecular management of 50 prospective patients with microphthalmia, anophthalmia and/or ocular coloboma. Br J Ophthalmol 2023; 107:1925-1935. [PMID: 36192130 DOI: 10.1136/bjo-2022-321991] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 09/22/2022] [Indexed: 11/03/2022]
Abstract
BACKGROUND/AIMS Microphthalmia, anophthalmia and coloboma (MAC) are clinically and genetically heterogenous rare developmental eye conditions, which contribute to a significant proportion of childhood blindness worldwide. Clear understanding of MAC aetiology and comorbidities is essential to providing patients with appropriate care. However, current management is unstandardised and molecular diagnostic rates remain low, particularly in those with unilateral presentation. To further understanding of clinical and genetic management of patients with MAC, we charted their real-world experience to ascertain optimal management pathways and yield from molecular analysis. METHODS A prospective cohort study of consecutive patients with MAC referred to the ocular genetics service at Moorfields Eye Hospital between 2017-2020. RESULTS Clinical analysis of 50 MAC patients (15 microphthalmia; 2 anophthalmia; 11 coloboma; and 22 mixed) from 44 unrelated families found 44% had additional ocular features (complex) and 34% had systemic involvement, most frequently intellectual/developmental delay (8/17). Molecular analysis of 39 families using targeted gene panels, whole genome sequencing and microarray comparative genomic hybridisation identified genetic causes in, 28% including novel variants in six known MAC genes (SOX2, KMT2D, MAB21L2, ALDH1A3, BCOR and FOXE3), and a molecular diagnostic rate of 33% for both bilateral and unilateral cohorts. New phenotypic associations were found for FOXE3 (bilateral sensorineural hearing loss) and MAB21L2 (unilateral microphthalmia). CONCLUSION This study highlights the importance of thorough clinical and molecular phenotyping of MAC patients to provide appropriate multidisciplinary care. Routine genetic testing for both unilateral and bilateral cases in the clinic may increase diagnostic rates in the future, helping elucidate genotype-phenotype correlations and informing genetic counselling.
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Affiliation(s)
- Philippa Harding
- Institute of Ophthalmology, University College London, London, UK
| | - Sri Gore
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Great Ormond Street Hospital For Children NHS Trust, London, UK
| | - Samantha Malka
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | | | - Ngozi Oluonye
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Great Ormond Street Hospital For Children NHS Trust, London, UK
| | - Mariya Moosajee
- Institute of Ophthalmology, University College London, London, UK
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- Great Ormond Street Hospital For Children NHS Trust, London, UK
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Wang X, Tan S, Yang S, Liu X, Lei J, Li H. Activation of Sonic Hedgehog Signaling Pathway Regulates Human Trabecular Meshwork Cell Function. J Ocul Pharmacol Ther 2023; 39:430-438. [PMID: 37307020 DOI: 10.1089/jop.2023.0022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023] Open
Abstract
Purpose: To investigate the effects of Sonic hedgehog (Shh) signaling on primary human trabecular meshwork (HTM) cells. Methods: Primary HTM cells were isolated from healthy donors and cultured. Recombinant Shh (rShh) protein and cyclopamine were used to activate and inhibit the Shh signaling pathway, respectively. A cell viability assay was performed to assess the effects of rShh on the activity of primary HTM cells. Functional assessment of cell adhesion and phagocytosis was also performed. The proportion of apoptotic cells was examined using flow cytometry. Fibronectin (FN) and transforming growth factor beta2 (TGF-β2) protein were detected to assess the influence of rShh on the metabolism of the extracellular matrix (ECM). Real-time polymerase chain reaction (RT-PCR) and western blot analyses were used to examine mRNA and protein expression of Shh signaling pathway-associated factors GLI Family Zinc Finger 1 (GLI1) and Suppressor of Fused (SUFU). Results: rShh significantly enhanced primary HTM cell viability at a concentration of 0.5 μg/mL. rShh increased the adhesion and phagocytic abilities of primary HTM cells, and decreased cell apoptosis. FN and TGF-β2 protein expression increased in primary HTM cells treated with rShh. rShh upregulated the transcriptional activity and protein levels of GLI1, and downregulated those of SUFU. Correspondingly, the rShh-induced GLI1 upexpression was partially blocked by pretreatment with the Shh pathway inhibitor cyclopamine at a concentration of 10 μM. Conclusions: Activation of Shh signaling can regulate the function of primary HTM cells through GLI1. Regulation of Shh signaling may be a potential target for attenuating cell damage in glaucoma.
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Affiliation(s)
- Xiaochen Wang
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Lab of Ophthalmology, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Sisi Tan
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Lab of Ophthalmology, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Shuang Yang
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Lab of Ophthalmology, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Xianmao Liu
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Lab of Ophthalmology, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Junqin Lei
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Lab of Ophthalmology, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
| | - Hong Li
- Department of Ophthalmology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Lab of Ophthalmology, Chongqing Eye Institute, Chongqing Branch of National Clinical Research Center for Ocular Diseases, Chongqing, China
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Jackson D, Moosajee M. The Genetic Determinants of Axial Length: From Microphthalmia to High Myopia in Childhood. Annu Rev Genomics Hum Genet 2023; 24:177-202. [PMID: 37624667 DOI: 10.1146/annurev-genom-102722-090617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/27/2023]
Abstract
The axial length of the eye is critical for normal visual function by enabling light to precisely focus on the retina. The mean axial length of the adult human eye is 23.5 mm, but the molecular mechanisms regulating ocular axial length remain poorly understood. Underdevelopment can lead to microphthalmia (defined as a small eye with an axial length of less than 19 mm at 1 year of age or less than 21 mm in adulthood) within the first trimester of pregnancy. However, continued overgrowth can lead to axial high myopia (an enlarged eye with an axial length of 26.5 mm or more) at any age. Both conditions show high genetic and phenotypic heterogeneity associated with significant visual morbidity worldwide. More than 90 genes can contribute to microphthalmia, and several hundred genes are associated with myopia, yet diagnostic yields are low. Crucially, the genetic pathways underpinning the specification of eye size are only now being discovered, with evidence suggesting that shared molecular pathways regulate under- or overgrowth of the eye. Improving our mechanistic understanding of axial length determination will help better inform us of genotype-phenotype correlations in both microphthalmia and myopia, dissect gene-environment interactions in myopia, and develop postnatal therapies that may influence overall eye growth.
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Affiliation(s)
- Daniel Jackson
- Institute of Ophthalmology, University College London, London, United Kingdom;
| | - Mariya Moosajee
- Institute of Ophthalmology, University College London, London, United Kingdom;
- The Francis Crick Institute, London, United Kingdom
- Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom
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Chesneau B, Ivashchenko V, Habib C, Gaston V, Escudié F, Morel G, Capri Y, Vincent-Delorme C, Calvas P, Chassaing N, Plaisancié J. Evaluation of somatic and/or germline mosaicism in congenital malformation of the eye. Eur J Hum Genet 2023; 31:526-530. [PMID: 36404347 PMCID: PMC10172375 DOI: 10.1038/s41431-022-01234-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/17/2022] [Accepted: 11/01/2022] [Indexed: 11/22/2022] Open
Abstract
Microphthalmia, Anophthalmia and Coloboma (MAC) form a spectrum of congenital eye malformations responsible for severe visual impairment. Despite the exploration of hundreds of genes by High-Throughput Sequencing (HTS), most of the patients remain without genetic diagnosis. One explanation could be the not yet demonstrated involvement of somatic mosaicism (undetected by conventional analysis pipelines) in those patients. Furthermore, the proportion of parental germline mosaicism in presumed de novo variations is still unknown in ocular malformations. Thus, using dedicated bioinformatics pipeline designed to detect mosaic variants, we reanalysed the sequencing data obtained from a 119 ocular development genes panel performed on blood samples of 78 probands with sporadic MAC without genetic diagnosis. Using the same HTS strategy, we sequenced 80 asymptomatic parents of 41 probands carrying a disease-causing variant in an ocular development gene considered de novo after Sanger sequencing of both parents. Reanalysis of the previously sequencing data did not find any mosaic variant in probands without genetic diagnosis. However, HTS of parents revealed undetected SOX2 and PAX6 mosaic variants in two parents. Finally, this work, performed on two large cohorts of patients with MAC spectrum, provides for the first time an overview of the interest of looking for mosaicism in ocular development disorders. Somatic mosaicism does not appear to be frequent in MAC spectrum and might explain only few diagnoses. Thus, other approaches such as whole genome sequencing should be considered in those patients. Parental mosaicism is however not that rare (around 5%) and challenging for genetic counselling.
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Affiliation(s)
- Bertrand Chesneau
- Service de Génétique Médicale, Hôpital Purpan, CHU de Toulouse, Toulouse, France
- Centre de Référence pour les Affections Rares en Génétique Ophtalmologique (CARGO), CHU de Toulouse, Toulouse, France
| | | | - Christophe Habib
- Service de Génétique Médicale, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Véronique Gaston
- Service de Génétique Médicale, Hôpital Purpan, CHU de Toulouse, Toulouse, France
| | - Fréderic Escudié
- Département d'anatomopathologie, IUCT Oncopole, Toulouse, France
| | - Godelieve Morel
- Service de Génétique Médicale, CHU de Rennes, Rennes, France
| | - Yline Capri
- Service de Génétique Médicale, Hôpital Robert Debré, APHP, Paris, France
| | | | - Patrick Calvas
- Service de Génétique Médicale, Hôpital Purpan, CHU de Toulouse, Toulouse, France
- Centre de Référence pour les Affections Rares en Génétique Ophtalmologique (CARGO), CHU de Toulouse, Toulouse, France
| | - Nicolas Chassaing
- Service de Génétique Médicale, Hôpital Purpan, CHU de Toulouse, Toulouse, France
- Centre de Référence pour les Affections Rares en Génétique Ophtalmologique (CARGO), CHU de Toulouse, Toulouse, France
| | - Julie Plaisancié
- Service de Génétique Médicale, Hôpital Purpan, CHU de Toulouse, Toulouse, France.
- Centre de Référence pour les Affections Rares en Génétique Ophtalmologique (CARGO), CHU de Toulouse, Toulouse, France.
- INSERM U1214, ToNIC, Université Toulouse III, Toulouse, France.
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Huang L, Peng J, Xie Y, Zhou Y, Wang X, Wang H, Gui J, Li N. Diversity of clinical phenotypes in a cohort of Han Chinese patients with PAX6 variants. Front Genet 2023; 14:1011060. [PMID: 36816037 PMCID: PMC9934858 DOI: 10.3389/fgene.2023.1011060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 01/20/2023] [Indexed: 02/05/2023] Open
Abstract
The PAX6 gene plays an important role in ocular development. Mutations of the PAX6 gene may result in a series of ocular abnormalities, including congenital aniridia, anterior segment dysgenesis (ASD), progressive corneal opacification, glaucoma, and hypoplasia of the fovea and optic nerve, leading to reduced visual acuity and even blindness. This study aimed to describe the diversity of clinical features caused by PAX6 pathogenic variants in 45 Han Chinese patients from 23 unrelated families. All patients underwent detailed clinical assessment. Genetic testing was performed to identify pathogenic variations in the PAX6 gene by next-generation sequencing, minigene splicing assay, RT-qPCR, and long-range PCR. Twenty pathogenic variations were detected in the PAX6 gene from 12 pedigrees and 11 sporadic patients, of which 12 were previously reported and 8 were novel. The clinical phenotypes obtained as a result of the PAX6 gene mutations were complicated and vary among patients, even among those who carried the same variants. Genetic testing is helpful for differential diagnosis. Our genetic findings will expand the spectrum of pathogenic variations in the PAX6 gene. PAX6 pathogenic variants not only cause defects in ocular tissues, such as the iris and retina, but also lead to maldevelopment of the whole eye, resulting in microphthalmia.
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Affiliation(s)
- Lijuan Huang
- Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China,Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, Beijing, China
| | - Jiajia Peng
- Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, Beijing, China
| | - Yan Xie
- Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, Beijing, China
| | - Yunyu Zhou
- Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, Beijing, China
| | - Xiaolin Wang
- Laboratory of Tumor Immunology, Beijing Children’s Hospital, National Center for Children’s Health, Beijing Pediatric Research Institute, Capital Medical University, Beijing, China
| | - Hui Wang
- Laboratory of Tumor Immunology, Beijing Children’s Hospital, National Center for Children’s Health, Beijing Pediatric Research Institute, Capital Medical University, Beijing, China
| | - Jingang Gui
- Laboratory of Tumor Immunology, Beijing Children’s Hospital, National Center for Children’s Health, Beijing Pediatric Research Institute, Capital Medical University, Beijing, China,*Correspondence: Jingang Gui, ; Ningdong Li,
| | - Ningdong Li
- Department of Ophthalmology, The Second Affiliated Hospital of Fujian Medical University, Quanzhou, China,Department of Ophthalmology, Beijing Children’s Hospital, Capital Medical University, Beijing, China,Department of Ophthalmology, Shanghai General Hospital, Shanghai, China,Department of Ophthalmology, Children’s Hospital, Capital Institute of Pediatrics, Beijing, China,*Correspondence: Jingang Gui, ; Ningdong Li,
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6
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Li W, He XD, Yang ZT, Han DM, Sun Y, Chen YX, Han XT, Guo SC, Ma YT, Jin X, Yang HM, Gao Y, Wang ZS, Li JK, He W. De Novo Mutations Contributes Approximately 7% of Pathogenicity in Inherited Eye Diseases. Invest Ophthalmol Vis Sci 2023; 64:5. [PMID: 36729443 PMCID: PMC9907368 DOI: 10.1167/iovs.64.2.5] [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] [Indexed: 02/03/2023] Open
Abstract
Purpose The purpose of this study was to describe genotype-phenotype associations and novel insights into genetic characteristics in a trio-based cohort of inherited eye diseases (IEDs). Methods To determine the etiological role of de novo mutations (DNMs) and genetic profile in IEDs, we retrospectively reviewed a large cohort of proband-parent trios of Chinese origin. The patients underwent a detailed examination and was clinically diagnosed by an ophthalmologist. Panel-based targeted exome sequencing was performed on DNA extracted from blood samples, containing coding regions of 792 IED-causative genes and their flanking exons. All participants underwent genetic testing. Results All proband-parent trios were divided into 22 subgroups, the overall diagnostic yield was 48.67% (605/1243), ranging from 4% to 94.44% for each of the subgroups. A total of 108 IED-causative genes were identified, with the top 24 genes explaining 67% of the 605 genetically solved trios. The genetic etiology of 6.76% (84/1243) of the trio was attributed to disease-causative DNMs, and the top 3 subgroups with the highest incidence of DNM were aniridia (n = 40%), Marfan syndrome/ectopia lentis (n = 38.78%), and retinoblastoma (n = 37.04%). The top 10 genes have a diagnostic yield of DNM greater than 3.5% in their subgroups, including PAX6 (40.00%), FBN1 (38.78%), RB1 (37.04%), CRX (10.34%), CHM (9.09%), WFS1 (8.00%), RP1L1 (5.88%), RS1 (5.26%), PCDH15 (4.00%), and ABCA4 (3.51%). Additionally, the incidence of DNM in offspring showed a trend of correlation with paternal age at reproduction, but not statistically significant with paternal (P = 0.154) and maternal (P = 0.959) age at reproduction. Conclusions Trios-based genetic analysis has high accuracy and validity. Our study helps to quantify the burden of the full spectrum IED caused by each gene, offers novel potential for elucidating etiology, and plays a crucial role in genetic counseling and patient management.
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Affiliation(s)
- Wei Li
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China,BGI-Shenzhen, Shenzhen, China
| | | | - Zheng-Tao Yang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China,BGI-Shenzhen, Shenzhen, China
| | - Dong-Ming Han
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China,BGI-Shenzhen, Shenzhen, China
| | - Yan Sun
- He University, Shenyang, China
| | - Yan-Xian Chen
- Department of Ophthalmology, Peking University Shenzhen Hospital, Shenzhen Peking University-The Hong Kong University of Science and Technology Medical Center, Shenzhen, China
| | - Xiao-Tong Han
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou, China
| | - Si-Cheng Guo
- BGI-Shenzhen, Shenzhen, China,College of Plant Protection, Hunan Agricultural University, Changsha, Hunan, China
| | - Yu-Ting Ma
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China,BGI-Shenzhen, Shenzhen, China
| | - Xin Jin
- BGI-Shenzhen, Shenzhen, China
| | - Huan-Ming Yang
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China,BGI-Shenzhen, Shenzhen, China
| | - Ya Gao
- BGI-Shenzhen, Shenzhen, China
| | | | | | - Wei He
- He University, Shenyang, China
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Cardozo MJ, Sánchez-Bustamante E, Bovolenta P. Optic cup morphogenesis across species and related inborn human eye defects. Development 2023; 150:286775. [PMID: 36714981 PMCID: PMC10110496 DOI: 10.1242/dev.200399] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The vertebrate eye is shaped as a cup, a conformation that optimizes vision and is acquired early in development through a process known as optic cup morphogenesis. Imaging living, transparent teleost embryos and mammalian stem cell-derived organoids has provided insights into the rearrangements that eye progenitors undergo to adopt such a shape. Molecular and pharmacological interference with these rearrangements has further identified the underlying molecular machineries and the physical forces involved in this morphogenetic process. In this Review, we summarize the resulting scenarios and proposed models that include common and species-specific events. We further discuss how these studies and those in environmentally adapted blind species may shed light on human inborn eye malformations that result from failures in optic cup morphogenesis, including microphthalmia, anophthalmia and coloboma.
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Affiliation(s)
- Marcos J Cardozo
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
| | - Elena Sánchez-Bustamante
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
| | - Paola Bovolenta
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid, c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), c/ Nicolás Cabrera 1, Cantoblanco, Madrid 28049, Spain
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Meng F, Li X, Zhang J, Gao Z, Yang X, Liu Z, Liu Y, Guo T, Wang L, Yang L, Wang Z. Single amino acid variation in MAB21L1 is dominantly associated with congenital eye defects. J Med Genet 2022:jmg-2022-108506. [DOI: 10.1136/jmg-2022-108506] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 10/19/2022] [Indexed: 11/30/2022]
Abstract
BackgroundDiagnosis of a genetic disease and determination of the causative molecular lesion rely on the availability of the disease-associated pedigrees. Microphthalmia is a congenital eye defect due to an insufficiently developed visual system; its prevalence is 1–3 in 10 000 live births.ObjectiveWe analysed a pedigree exhibiting autosomal dominant inheritance of microphthalmia to determine the genetic lesion; used AlphaFold2 to predict the changes in the protein’s 3-Dimensional structure; and compared wild-type and variant proteins in cultured cells or Drosophila model was used to explore the cellular or developmental function of the encoded product.ResultsWe identified a novel missense variation, F52L, in MAB21L1 that is absent in population databases and present exclusively in the individuals diagnosed with microphthalmia in this pedigree. Common structural changes were predicted for the disease-associated variants clustered at amino acids 49–52, and these variant products were also predominantly trapped in the cytoplasm of cultured human lens epithelia. To recapitulate its dominant effect in development, we expressed the Drosophila homologue corresponding to MAB21L1F52Land caused malformation of sensory organs.ConclusionMutations at the residues 49–52 of MAB21L1 compromise eye development. We recommend includingMAB21L1in the genetic testing panel for congenital eye disorders.
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Tang Y, Xu J, Lu Y, Zheng T. Three Novel Mutations of Microphthalmos Identified in Two Chinese Families. PHENOMICS (CHAM, SWITZERLAND) 2022; 2:254-260. [PMID: 36939803 PMCID: PMC9590552 DOI: 10.1007/s43657-022-00053-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 03/03/2022] [Accepted: 03/08/2022] [Indexed: 10/18/2022]
Abstract
Genetic alterations are a major cause of microphthalmos, while novel-related genes and mutations in microphthalmos have rarely been explored. To identify the underlying genetic defect responsible for microphthalmos eyes in two three-generation Chinese families, we screened 425 genes involved in common inherited non-syndromic eye diseases with next-generation sequencing-based target capture sequencing of the two probands of two three-generation Chinese families diagnosed with microphthalmos. Variants were filtered and analyzed to identify possible disease-causing variants before Sanger sequencing validation. We enrolled two families with microphthalmos (Family 1: microphthalmos with congenital ocular coloboma and Family 2: simple microphthalmos). Two novel heterozygous mutations, Peroxidasin (PXDN) c.3165C>T (p.Pro1055Pro) and PXDN c.2640C>G (p.Arg880Arg), were found in Family 1, and Crystallin Beta B2 (CRYBB2) c.481G>A (p.Gly161Arg) was found in Family 2, but none of the mutations were found in the unaffected individuals, who were phenotypically normal. Multiple orthologous sequence alignment (MSA) revealed that the CRYBB2 p.Gly161Arg mutation was a deleterious effect mutation. In conclusion, the three novel mutations found in our study extend our current understanding of the genetic basis of microphthalmos and provide early pre-symptomatic diagnosis and emphasize the significance of genetic diagnosis of microphthalmos.
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Affiliation(s)
- Yating Tang
- grid.411079.a0000 0004 1757 8722Department of Ophthalmology and Eye Research Institute, Eye and ENT Hospital of Fudan University, Shanghai, 200031 China
- grid.506261.60000 0001 0706 7839NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, 200031, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, 200031 China
| | - Jie Xu
- grid.411079.a0000 0004 1757 8722Department of Ophthalmology and Eye Research Institute, Eye and ENT Hospital of Fudan University, Shanghai, 200031 China
- grid.506261.60000 0001 0706 7839NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, 200031, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, 200031 China
| | - Yi Lu
- grid.411079.a0000 0004 1757 8722Department of Ophthalmology and Eye Research Institute, Eye and ENT Hospital of Fudan University, Shanghai, 200031 China
- grid.506261.60000 0001 0706 7839NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, 200031, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, 200031 China
| | - Tianyu Zheng
- grid.411079.a0000 0004 1757 8722Department of Ophthalmology and Eye Research Institute, Eye and ENT Hospital of Fudan University, Shanghai, 200031 China
- grid.506261.60000 0001 0706 7839NHC Key Laboratory of Myopia (Fudan University), Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai, 200031, China
- Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai, 200031 China
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Novel Variant in Exon 3 of the BMP4 Gene Resulted in Ectopic Posterior Pituitary, Craniocervical Junction Dysmorphism and Limb Anomaly. Case Rep Pediatr 2022; 2022:8059409. [PMID: 35633847 PMCID: PMC9135578 DOI: 10.1155/2022/8059409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 04/07/2022] [Accepted: 05/09/2022] [Indexed: 11/29/2022] Open
Abstract
Introduction. Pituitary differentiation involves a large number of transcription factors. In particular, BMP4 expression is fundamental for pituitary gland commitment from the ventral diencephalon, suppressing Shh expression in Rathke's pouch. Pathogenic variants in BMP4 are reported in the literature with a broad phenotypic spectrum, including pituitary and brain malformations. Case Presentation. A five-year-old girl came to medical attention following a mild cervical trauma with onset of cervical pain. On clinical examination at birth, postaxial polydactyly type B of the left hand was observed and removed at 10 months of age. A cervical radiography was performed, and a suspicion of craniocervical junction malformation was made. A magnetic resonance imaging of the cervical spine was made, showing an ectopic posterior pituitary, associated with dysmorphism of the craniocervical junction. The anthropometric parameters were pubertal Tanner stage 1, weight 16 kg (z-score: −1.09), height 107 cm (z-score: −0.76), and BMI 14 kg/m2 (z-score: −0.92). Normal hormonal assessment was detected. Genetic analysis via next generation sequencing showed a novel de novo heterozygous variant (c.277 G > T, p.Glu93∗) in exon 3 of BMP4. Discussion. We described a novel mutation in BMP4, resulting in ectopic posterior pituitary with normal hormonal assessment, associated to craniocervical junction dysmorphism and limb anomaly. It is important to monitor patient's growth and puberty and to screen the onset of symptoms related to the deficiency of one or more anterior as well as posterior pituitary hormones.
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Silva AV, Firmino MO, Costa NL, Louro RO, Paquete CM. Investigation of the Molecular Mechanisms of the Eukaryotic Cytochrome-c Maturation System. Biomolecules 2022; 12:biom12040549. [PMID: 35454139 PMCID: PMC9028165 DOI: 10.3390/biom12040549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 04/04/2022] [Accepted: 04/05/2022] [Indexed: 02/01/2023] Open
Abstract
Cytochromes-c are ubiquitous heme proteins with enormous impact at the cellular level, being key players in metabolic processes such as electron transfer chains and apoptosis. The assembly of these proteins requires maturation systems that catalyse the formation of the covalent thioether bond between two cysteine residues and the vinyl groups of the heme. System III is the maturation system present in Eukaryotes, designated CcHL or HCCS. This System requires a specific amino acid sequence in the apocytochrome to be recognized as a substrate and for heme insertion. To explore the recognition mechanisms of CcHL, the bacterial tetraheme cytochrome STC from Shewanella oneidensis MR-1, which is not a native substrate for System III, was mutated to be identified as a substrate. The results obtained show that it is possible to convert a bacterial cytochrome as a substrate by CcHL, but the presence of the recognition sequence is not the only factor that induces the maturation of a holocytochrome by System III. The location of this sequence in the polypeptide also plays a role in the maturation of the c-type cytochrome. Furthermore, CcHL appears to be able to catalyse the binding of only one heme per polypeptide chain, being unable to assemble multiheme cytochromes c, in contrast with bacterial maturation systems.
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12
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Demographics and histopathological characteristics of enucleated microphthalmic globes. Sci Rep 2022; 12:5283. [PMID: 35347187 PMCID: PMC8960817 DOI: 10.1038/s41598-022-09261-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Accepted: 03/21/2022] [Indexed: 01/25/2023] Open
Abstract
Microphthalmia is a rare ocular anomaly with a poorly understood etiology that is most likely related to heritable and/or environmental factors. Many papers have been published pertaining to the clinical manifestations and management of this condition; however, few reports have reported detailed histopathological findings, which are the focus of this study, in addition to highlighting the basic demographics in these cases. This was a retrospective, observational study of all consecutive enucleated microphthalmic globes (with or without cysts) at 2 tertiary eye hospitals in Riyadh, Saudi Arabia. Globes were classified into 2 groups: severe microphthalmos (axial length or mean diameter less than 10 mm in infancy or 12 mm after age 1 year) and mild microphthalmos based on larger measurements. Clinical and demographic data collected included sex, age at enucleation, eye involvement, nationality/region, consanguinity, family history of eye anomaly, pregnancy, systemic disease, or syndromes. For histopathological data, a descriptive analysis was mostly performed. For correlations of some of our qualitative data, Fisher's exact test was used. Eleven cases (6 mild and 5 severe microphthalmos) were initially identified with a female to male ratio of 4:7. Ten patients were Saudis, 7 of whom were from the central region. Consanguinity was found in 36% (4/11), and 3 of them had other ocular or systemic abnormalities (duodenal atresia, microcephaly, kidney agenesis, cryptophthalmos, and dysmorphic facial features). Histopathological data were available for 10 cases, half of which showed a coloboma and/or anterior segment anomaly. There was no significant correlation among gender, severity of microphthalmos or the presence of coloboma, although severe microphthalmic globes had a higher median of abnormal intraocular structures (9-interquartile range = 2 compared to 6-interquartile range = 1 in the mild group). Aphakia was found in half of the globes with associated anterior segment dysgenesis. We have concluded that microphthalmos is a visually disabling congenital anomaly that can be isolated or associated with other periocular or systemic anomalies, possibly in relation to consanguinity in our cases. Congenital aphakia was found in half of these cases and was mostly associated with absent Descemet's membrane and agenesis of anterior chamber angle structures, supporting previously suggested embryological concepts. These findings necessitate further wider genetic testing and proper premarital counseling in Saudi Arabia.
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13
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Ren X, Gao Y, Lin Y, Fu X, Xiao L, Wang X, Zeng Z, Bao L, Yan N, Zhang M, Tang L. A Novel Mutation in the Membrane Frizzled-Related Protein Gene for Posterior Microphthalmia, Non-pigmented Retinitis Pigmentosa, Optic Nerve Drusen, and Retinoschisis in a Consanguineous Family. Front Med (Lausanne) 2022; 9:835621. [PMID: 35402469 PMCID: PMC8987310 DOI: 10.3389/fmed.2022.835621] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/08/2022] [Indexed: 11/13/2022] Open
Abstract
Background Microphthalmos (MCO) is a rare developmental defect characterized by small malformed eyes. Our study aimed to describe the clinical characteristics of posterior microphthalmos syndrome caused by a novel variant in MFRP gene in a Chinese patient. Methods Complete ophthalmologic examinations were performed for the proband and proband's family members. Whole exon sequencing (WES) and Sanger sequencing were used to identify the mutated genes, and bioinformatic analysis was undertaken to predict the effect of this variant. Results Clinical analysis showed that the proband had reduced axial length (17.95 and 17.98 mm) with normal-size corneas and shallow anterior chamber depth. Fundus photography showed scattered yellowish-white spots in the whole retina with cup-to-disc ratios of 0.95 in both eyes. Retinoschisis in the inner nuclear layer and reduced outer retina thickness were apparent on OCT examination, and optic nerve drusen demonstrated increased autofluorescence in fundus autofluorescence (FAF). Perimeter examination revealed a tubular visual field for the right eye, and electroretinography (ERG) revealed a moderately reduced rod response combined with compromised cone response. Ocular examinations of the patient's family members were unremarkable. WES revealed that the proband had homozygous mutations in c.55-1 (IVS1) G>A in intron 1 for the MFRP gene. Both the proband's parents and offspring were confirmed to be heterozygous by Sanger sequencing. Bioinformatic analysis showed this mutation was deleterious. Conclusion We reported autosomal recessive posterior microphthalmia, atypical retinitis pigmentosa, and retinoschisis caused by a novel mutation in the MFRP gene in this consanguineous marriage family. Our study further broadens the mutation and phenotype spectrum of the MFRP gene in microphthalmia.
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Affiliation(s)
- Xiang Ren
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Yunxia Gao
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Yu Lin
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Xiangyu Fu
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Lirong Xiao
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Xiaoyue Wang
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Zhibing Zeng
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Li Bao
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Naihong Yan
- Research Laboratory of Ophthalmology and Vision Sciences, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Ming Zhang
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- *Correspondence: Ming Zhang
| | - Li Tang
- Ophthalmic Laboratory, Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
- Li Tang
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14
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Boerkoel PK, Dixon K, Fitzsimons C, Shen Y, Huynh S, Schlade-Bartusiak K, Culibrk L, Chan S, Boerkoel CF, Jones SJM, Chin HL. Long-read genome sequencing resolves a complex 13q structural variant associated with syndromic anophthalmia. Am J Med Genet A 2022; 188:1589-1594. [PMID: 35122461 DOI: 10.1002/ajmg.a.62676] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 12/31/2021] [Accepted: 01/08/2022] [Indexed: 11/05/2022]
Abstract
Microphthalmia, anophthalmia, and coloboma (MAC) are a heterogeneous spectrum of anomalous eye development and degeneration with genetic and environmental etiologies. Structural and copy number variants of chromosome 13 have been implicated in MAC; however, the specific loci involved in disease pathogenesis have not been well-defined. Herein we report a newborn with syndromic degenerative anophthalmia and a complex de novo rearrangement of chromosome 13q. Long-read genome sequencing improved the resolution and clinical interpretation of a duplication-triplication/inversion-duplication (DUP-TRP/INV-DUP) and terminal deletion. Sequence features at the breakpoint junctions suggested microhomology-mediated break-induced replication (MMBIR) of the maternal chromosome as the origin. Comparing this rearrangement to previously reported copy number alterations in 13q, we refine a putative dosage-sensitive critical region for MAC that might provide new insights into its molecular etiology.
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Affiliation(s)
- Pierre K Boerkoel
- MD Undergraduate Program, University of British Columbia, Vancouver, British Columbia, Canada
| | - Katherine Dixon
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.,Canada's Michael Smith Genome Sciences Centre, BC Cancer, Vancouver, British Columbia, Canada
| | | | - Yaoqing Shen
- Canada's Michael Smith Genome Sciences Centre, BC Cancer, Vancouver, British Columbia, Canada
| | - Stephanie Huynh
- Provincial Medical Genetics Program, Women's Hospital of British Columbia, Vancouver, British Columbia, Canada
| | - Kamilla Schlade-Bartusiak
- Department of Pathology, BC Children's Hospital, BC Women's Hospital & Health Centre, Vancouver, British Columbia, Canada
| | - Luka Culibrk
- Canada's Michael Smith Genome Sciences Centre, BC Cancer, Vancouver, British Columbia, Canada
| | - Simon Chan
- Canada's Michael Smith Genome Sciences Centre, BC Cancer, Vancouver, British Columbia, Canada
| | - Cornelius F Boerkoel
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.,Provincial Medical Genetics Program, Women's Hospital of British Columbia, Vancouver, British Columbia, Canada
| | - Steven J M Jones
- Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada.,Canada's Michael Smith Genome Sciences Centre, BC Cancer, Vancouver, British Columbia, Canada
| | - Hui-Lin Chin
- Provincial Medical Genetics Program, Women's Hospital of British Columbia, Vancouver, British Columbia, Canada.,Khoo Teck Puat-National University Children's Medical Institute, National University Hospital, Singapore, Singapore
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15
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Fahnehjelm C, Dafgård Kopp E, Wincent J, Güven E, Nilsson M, Olsson M, Teär Fahnehjelm K. Anophthalmia and microphthalmia in children: associated ocular, somatic and genetic morbidities and quality of life. Ophthalmic Genet 2022; 43:172-183. [PMID: 35105264 DOI: 10.1080/13816810.2021.1989600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE To report ocular outcome, somatic co-morbidities, genetics, and quality of life in children born with anophthalmia (A) or microphthalmia (M). METHODS Thirty-five children (19 boys) with A/M underwent ophthalmological examinations and a review of medical records. Parents of 12/22 cases completed the Pediatric Quality of Life Inventory (PedsQL). RESULTS Age at examination ranged from 7 months to 18 years (median 2.3 years). Ten cases were totally blind or had light perception. Isolated A/M occurred in 16/35 cases, while somatic, psychomotor, neuroradiological and/or genetic pathology occurred in 19/35 cases both in the bilateral (7/9) and in the unilateral group (12/26). Among 26 unilateral cases, 4/16 with one normal eye had associated problems compared to 9/10 if the contralateral eye was pathological (p < .01). There was an increased risk for heart defects in children with psychomotor delay (p = .04). Pathogenic genetic abnormalities were identified in 10/24 cases. Neuroimaging demonstrated pathology in 14/20 cases with corpus callosum dysgenesis (6/20) being the most common. The median total PedsQL score of parent reports for ages 2-12 was 52.4 (range 22.6-100). CONCLUSIONS Somatic, psychomotor and/or neuroradiological pathologies were more common in bila-teral than unilateral cases, but the difference was not significant. There was decreased risk in unilateral cases with one normal eye. Genetic defects occurred in both unilateral and bilateral cases. Health-related quality of life was reduced.
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Affiliation(s)
- Cecilia Fahnehjelm
- Department of Paediatrics, Astrid Lindgren Children's Hospital, Karolinska University Hospital, Stockholm, Sweden
| | - Eva Dafgård Kopp
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Oculoplastic and Orbital Services, St. Erik Eye Hospital, Stockholm, Sweden
| | - Josephine Wincent
- Department of Molecular Medicine and Surgery, Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden.,Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Evin Güven
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Paediatric Ophthalmology, Strabismus and Electrophysiology, St. Erik Eye Hospital, Stockholm, Sweden
| | - Mattias Nilsson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Monica Olsson
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Paediatric Ophthalmology, Strabismus and Electrophysiology, St. Erik Eye Hospital, Stockholm, Sweden
| | - Kristina Teär Fahnehjelm
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,Department of Paediatric Ophthalmology, Strabismus and Electrophysiology, St. Erik Eye Hospital, Stockholm, Sweden
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16
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Duester G. Towards a Better Vision of Retinoic Acid Signaling during Eye Development. Cells 2022; 11:cells11030322. [PMID: 35159132 PMCID: PMC8834304 DOI: 10.3390/cells11030322] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/11/2022] [Accepted: 01/17/2022] [Indexed: 02/01/2023] Open
Abstract
Retinoic acid (RA) functions as an essential signal for development of the vertebrate eye by controlling the transcriptional regulatory activity of RA receptors (RARs). During eye development, the optic vesicles and later the retina generate RA as a metabolite of vitamin A (retinol). Retinol is first converted to retinaldehyde by retinol dehydrogenase 10 (RDH10) and then to RA by all three retinaldehyde dehydrogenases (ALDH1A1, ALDH1A2, and ALDH1A3). In early mouse embryos, RA diffuses to tissues throughout the optic placode, optic vesicle, and adjacent mesenchyme to stimulate folding of the optic vesicle to form the optic cup. RA later generated by the retina is needed for further morphogenesis of the optic cup and surrounding perioptic mesenchyme; loss of RA at this stage leads to microphthalmia and cornea plus eyelid defects. RA functions by binding to nuclear RARs at RA response elements (RAREs) that either activate or repress transcription of key genes. Binding of RA to RARs regulates recruitment of transcriptional coregulators such as nuclear receptor coactivator (NCOA) or nuclear receptor corepressor (NCOR), which in turn control binding of the generic coactivator p300 or the generic corepressor PRC2. No genes have been identified as direct targets of RA signaling during eye development, so future studies need to focus on identifying such genes and their RAREs. Studies designed to learn how RA normally controls eye development in vivo will provide basic knowledge valuable for determining how developmental eye defects occur and for improving strategies to treat eye defects.
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Affiliation(s)
- Gregg Duester
- Development, Aging, and Regeneration Program, Sanford Burnham Prebys Medical Discovery Institute, 10901 N. Torrey Pines Road, La Jolla, CA 92037, USA
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17
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Alkhairy S, Baig MM, Pasha UA. Unilateral Anophthalmic Socket Reconstruction With Dermis Fat Graft. Cureus 2021; 13:e18834. [PMID: 34804689 PMCID: PMC8592800 DOI: 10.7759/cureus.18834] [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] [Accepted: 10/16/2021] [Indexed: 11/05/2022] Open
Abstract
A 15-year-old girl presented with the complaint of a cosmetically disfigured right eye since birth. The initial assessment was carried out by way of a history and physical examination. The patient's history revealed no significant findings. Physical examination revealed that the right ophthalmic socket was seemingly devoid of an identifiable globe and ocular tissue, which is described as an anophthalmic socket. The conjunctival fornices appeared short, a finding which was more noticeable in the inferior conjunctival fornix. The patient's orbital volume was decreased. To increase the orbital volume, a dermis fat graft (DFG) was carefully taken from the gluteal region. The graft was then transposed to the anophthalmic socket and sutured to the conjunctiva and Tenon's capsule. A prosthetic eye was placed in the socket. Later, a second surgical intervention was performed to deepen the inferior fornix, for which a mucous membrane graft was taken from the lower lip. As a result of these interventions, all cosmetic and medical concerns of the patient regarding the anophthalmic socket were addressed. The success of this procedure speaks to the efficacy of DFGs in the repair of an anophthalmic socket.
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Affiliation(s)
- Saba Alkhairy
- Ophthalmology, Dow University of Health Sciences, Dow International Medical College, Karachi, PAK
| | - Mahad M Baig
- Ophthalmology, Dow University of Health Sciences, Dow International Medical College, Karachi, PAK
| | - Usman A Pasha
- Ophthalmology, Dow University of Health Sciences, Dow International Medical College, Karachi, PAK
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18
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Rafati M, Mohamadhashem F, Jalilian K, Hoseininasab F, Fakhri L, Hoseini A, Amiri H, Barati Z, Darzi Ramandi S, Mostofinezhad N, Mahmoudi AH, Ghaffari SR. Identification of a novel de novo variant in OTX2 in a patient with congenital microphthalmia using targeted next-generation sequencing followed by prenatal diagnosis. Ophthalmic Genet 2021; 43:262-267. [PMID: 34791963 DOI: 10.1080/13816810.2021.2002915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Next-generation sequencing has been proven to be a reliable method for the detection of genetic causes in heterogeneous ocular disorders. In this report an NGS-based diagnostic approach was taken to uncover the genetic etiology in a patient with coloboma and microphthalmia, a highly heterogeneous disease with intrafamilial phenotypic variability. MATERIALS AND METHODS Next generation sequencing using a targeted panel of 316 genes, was carried out in the proband. Prioritized variants were then identified and confirmed using Sanger sequencing. Prenatal diagnosis of the detected variant was then performed in the family. RESULTS A novel de novo frameshift variant c.157_164delTTCACTCG (p.Phe53fs) in OTX2, leading to a truncated protein, was identified. Prenatal diagnosis identified the same variant in the fetus. CONCLUSIONS This report demonstrates the importance of genetic counseling and underscores the efficiency and effectiveness of targeted NGS as a means of detecting variants in inherited eye disorders.
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Affiliation(s)
- Maryam Rafati
- Comprehensive Genetic Center, Hope Generation Foundation, Tehran, Iran.,Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.,Department of Genomics Gene Clinic, Tehran, Iran
| | - Faezeh Mohamadhashem
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Koosha Jalilian
- Department of Cell and Molecular Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran
| | - Fatemeh Hoseininasab
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Laya Fakhri
- Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran
| | - Azadeh Hoseini
- Comprehensive Genetic Center, Hope Generation Foundation, Tehran, Iran
| | - Hosna Amiri
- Comprehensive Genetic Center, Hope Generation Foundation, Tehran, Iran
| | - Zeinab Barati
- Comprehensive Genetic Center, Hope Generation Foundation, Tehran, Iran
| | | | | | | | - Saeed Reza Ghaffari
- Comprehensive Genetic Center, Hope Generation Foundation, Tehran, Iran.,Reproductive Biotechnology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.,Department of Genomics Gene Clinic, Tehran, Iran
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19
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Trigila AP, Pisciottano F, Franchini LF. Hearing loss genes reveal patterns of adaptive evolution at the coding and non-coding levels in mammals. BMC Biol 2021; 19:244. [PMID: 34784928 PMCID: PMC8594068 DOI: 10.1186/s12915-021-01170-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Accepted: 10/21/2021] [Indexed: 11/26/2022] Open
Abstract
Background Mammals possess unique hearing capacities that differ significantly from those of the rest of the amniotes. In order to gain insights into the evolution of the mammalian inner ear, we aim to identify the set of genetic changes and the evolutionary forces that underlie this process. We hypothesize that genes that impair hearing when mutated in humans or in mice (hearing loss (HL) genes) must play important roles in the development and physiology of the inner ear and may have been targets of selective forces across the evolution of mammals. Additionally, we investigated if these HL genes underwent a human-specific evolutionary process that could underlie the evolution of phenotypic traits that characterize human hearing. Results We compiled a dataset of HL genes including non-syndromic deafness genes identified by genetic screenings in humans and mice. We found that many genes including those required for the normal function of the inner ear such as LOXHD1, TMC1, OTOF, CDH23, and PCDH15 show strong signatures of positive selection. We also found numerous noncoding accelerated regions in HL genes, and among them, we identified active transcriptional enhancers through functional enhancer assays in transgenic zebrafish. Conclusions Our results indicate that the key inner ear genes and regulatory regions underwent adaptive evolution in the basal branch of mammals and along the human-specific branch, suggesting that they could have played an important role in the functional remodeling of the cochlea. Altogether, our data suggest that morphological and functional evolution could be attained through molecular changes affecting both coding and noncoding regulatory regions. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01170-6.
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Affiliation(s)
- Anabella P Trigila
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1428, Buenos Aires, Argentina
| | - Francisco Pisciottano
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1428, Buenos Aires, Argentina.,Current address: Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1428, Buenos Aires, Argentina
| | - Lucía F Franchini
- Instituto de Investigaciones en Ingeniería Genética y Biología Molecular (INGEBI), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1428, Buenos Aires, Argentina.
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20
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Ji Y, Yan T, Zhu S, Wu R, Zhu M, Zhang Y, Guo C, Yao K. The Integrative Analysis of Competitive Endogenous RNA Regulatory Networks in Coronary Artery Disease. Front Cardiovasc Med 2021; 8:647953. [PMID: 34631806 PMCID: PMC8492936 DOI: 10.3389/fcvm.2021.647953] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2020] [Accepted: 08/25/2021] [Indexed: 12/25/2022] Open
Abstract
Background: Coronary artery disease (CAD) is the leading cause of cardiovascular death. The competitive endogenous RNAs (ceRNAs) hypothesis is a new theory that explains the relationship between lncRNAs and miRNAs. The mechanism of ceRNAs in the pathological process of CAD has not been fully elucidated. The objective of this study was to explore the ceRNA mechanism in CAD using the integrative bioinformatics analysis and provide new research ideas for the occurrence and development of CAD. Methods: The GSE113079 dataset was downloaded, and differentially expressed lncRNAs (DElncRNAs) and genes (DEGs) were identified using the limma package in the R language. Weighted gene correlation network analysis (WGCNA) was performed on DElncRNAs and DEGs to explore lncRNAs and genes associated with CAD. Functional enrichment analysis was performed on hub genes in the significant module identified via WGCNA. Four online databases, including TargetScan, miRDB, miRTarBase, and Starbase, combined with an online tool, miRWalk, were used to construct ceRNA regulatory networks. Results: DEGs were clustered into ten co-expression modules with different colors using WGCNA. The brown module was identified as the key module with the highest correlation coefficient. 188 hub genes were identified in the brown module for functional enrichment analysis. DElncRNAs were clustered into sixteen modules, including seven modules related to CAD with the correlation coefficient more than 0.5. Three ceRNA networks were identified, including OIP5-AS1-miR-204-5p/miR-211-5p-SMOC1, OIP5-AS1-miR-92b-3p-DKK3, and OIP5-AS1-miR-25-3p-TMEM184B. Conclusion: Three ceRNA regulatory networks identified in this study may play crucial roles in the occurrence and development of CAD, which provide novel insights into the ceRNA mechanism in CAD.
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Affiliation(s)
- Yuyao Ji
- Department of Cardiology, Zhongshan Hospital, Shanghai Institute of Cardiovascular Diseases, Fudan University, Shanghai, China
| | - Tao Yan
- Department of Cardiovascular Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Shijie Zhu
- Department of Cardiovascular Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Runda Wu
- Department of Cardiology, Zhongshan Hospital, Shanghai Institute of Cardiovascular Diseases, Fudan University, Shanghai, China
| | - Miao Zhu
- Department of Cardiovascular Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Yangyang Zhang
- Department of Cardiovascular Surgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Changfa Guo
- Department of Cardiovascular Surgery, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Kang Yao
- Department of Cardiology, Zhongshan Hospital, Shanghai Institute of Cardiovascular Diseases, Fudan University, Shanghai, China
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21
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Khandwala N, Besirli C, Bohnsack BL. Outcomes and surgical management of persistent fetal vasculature. BMJ Open Ophthalmol 2021; 6:e000656. [PMID: 34013048 PMCID: PMC8094357 DOI: 10.1136/bmjophth-2020-000656] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 03/13/2021] [Accepted: 04/16/2021] [Indexed: 11/11/2022] Open
Abstract
Objective To analyse outcomes in different forms of persistent fetal vasculature (PFV). Methods and analysis Retrospective cohort study at a university-based practice of children presenting with PFV between 2011 and 2020. Exclusion criteria was surgical management outside of our institution and follow-up less than 1 month. Wilcoxon and Student’s t-tests were used for statistical analysis. Results Forty-six eyes of 45 patients presented with PFV at 16.7±31.3 (median 2.8) months old with 32.6±29.8 (median 22.5) months of follow-up. Types of PFV included: mild combined anterior-posterior (23 eyes, 50%), severe combined anterior-posterior (18 eyes, 39%), severe anterior (3 eyes, 7%), mild anterior (1 eye, 2%) and posterior (1 eye, 2%). Thirty-two eyes (70%) underwent PFV surgical correction; lensectomy (13 mild combined), vitrectomy (3 mild combined), sequential lensectomy then vitrectomy (3 severe combined), combined lensectomy-vitrectomy (11 severe anterior or severe combined), laser retinopexy (1 mild combined). Five eyes required additional vitrectomy surgery for retinal detachment, fold or cyclitic membrane. Nine eyes developed glaucoma, six requiring Intraocular pressure (IOP)-lowering surgery. At final follow-up, 32 eyes had at least form vision and 6 eyes were aversive to light. Eight eyes, all which were severe combined, and four that did not undergo PFV surgery, were unable to detect light due to phthisis bulbi (7) and optic nerve hypoplasia (1). Conclusions Classification of PFV is important in determining surgical approach with severe cases often requiring both lensectomy and vitrectomy for optimal anatomic and functional outcomes.
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Affiliation(s)
- Nikhila Khandwala
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - Cagri Besirli
- Department of Ophthalmology and Visual Sciences, University of Michigan, Ann Arbor, Michigan, USA
| | - Brenda L Bohnsack
- Ophthalmology and Visual Sciences, Ann and Robert H Lurie Children's Hospital of Chicago, Chicago, Illinois, USA.,Ophthalmology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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22
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Kougou Ntoutoume AR, Mekyna S, Assila S, Amazouzi A, Cherkaoui O. [Isolated congenital anophthalmia and microphthalmia: Report of 3 cases]. J Fr Ophtalmol 2020; 44:e75-e77. [PMID: 33341290 DOI: 10.1016/j.jfo.2020.04.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Accepted: 04/17/2020] [Indexed: 11/17/2022]
Affiliation(s)
- A R Kougou Ntoutoume
- Faculté de médecine et de pharmacie, université Mohammed V, service ophtalmologie A, CHU Ibn Sina, hôpital des spécialités de Rabat, quartier Souissi, Rabat, Maroc.
| | - S Mekyna
- Faculté de médecine et de pharmacie, université Mohammed V, service ophtalmologie A, CHU Ibn Sina, hôpital des spécialités de Rabat, quartier Souissi, Rabat, Maroc
| | - S Assila
- Faculté de médecine et de pharmacie, université Mohammed V, service ophtalmologie A, CHU Ibn Sina, hôpital des spécialités de Rabat, quartier Souissi, Rabat, Maroc
| | - A Amazouzi
- Faculté de médecine et de pharmacie, université Mohammed V, service ophtalmologie A, CHU Ibn Sina, hôpital des spécialités de Rabat, quartier Souissi, Rabat, Maroc
| | - O Cherkaoui
- Faculté de médecine et de pharmacie, université Mohammed V, service ophtalmologie A, CHU Ibn Sina, hôpital des spécialités de Rabat, quartier Souissi, Rabat, Maroc
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23
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Ghosh S, Carden CF, Juras R, Mendoza MN, Jevit MJ, Castaneda C, Phelps O, Dube J, Kelley DE, Varner DD, Love CC, Raudsepp T. Two Novel Cases of Autosomal Translocations in the Horse: Warmblood Family Segregating t(4;30) and a Cloned Arabian with a de novo t(12;25). Cytogenet Genome Res 2020; 160:688-697. [PMID: 33326979 DOI: 10.1159/000512206] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 10/07/2020] [Indexed: 11/19/2022] Open
Abstract
We report 2 novel autosomal translocations in the horse. In Case 1, a breeding stallion with a balanced t(4p;30) had produced normal foals and those with congenital abnormalities. Of his 9 phenotypically normal offspring, 4 had normal karyotypes, 4 had balanced t(4p;30), and 1 carried an unbalanced translocation with tertiary trisomy of 4p. We argue that unbalanced forms of t(4p;30) are more tolerated and result in viable congenital abnormalities, without causing embryonic death like all other known equine autosomal translocations. In Case 2, two stallions produced by somatic cell nuclear transfer from the same donor were karyotyped because of fertility issues. A balanced translocation t(12q;25) was found in one, but not in the other clone. The findings underscore the importance of routine cytogenetic screening of breeding animals and animals produced by assisted reproductive technologies. These cases will contribute to molecular studies of translocation breakpoints and their genetic consequences in the horse.
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Affiliation(s)
- Sharmila Ghosh
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | | | - Rytis Juras
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Mayra N Mendoza
- Estación Experimental Agraria Chincha, Dirección de Recursos Genéticos y Biotecnología, Instituto Nacional de Innovación Agraria, Ica, Peru
| | - Matthew J Jevit
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Caitlin Castaneda
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Olivia Phelps
- Powder River Veterinary Hospital & Supply, Kaycee, Wyoming, USA
| | - Jessie Dube
- Powder River Veterinary Hospital & Supply, Kaycee, Wyoming, USA
| | - Dale E Kelley
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Dickson D Varner
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Charley C Love
- Department of Large Animal Clinical Sciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA
| | - Terje Raudsepp
- Department of Veterinary Integrative Biosciences, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, USA,
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24
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Taha Najim R, Topa A, Jugård Y, Casslén B, Odersjö M, Andersson Grönlund M. Children and young adults with anophthalmia and microphthalmia: Diagnosis and Management. Acta Ophthalmol 2020; 98:848-858. [PMID: 32436650 DOI: 10.1111/aos.14427] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2019] [Accepted: 03/11/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE Congenital anophthalmia (A) and microphthalmia (M) are rare developmental defects, which could be isolated or syndromic. Our objective was to describe a cohort of children and young adults with A/M treated with ocular prosthesis, emphasizing clinical features, diagnosis, treatment, and follow-up. METHODS Eighteen individuals (10 female) with unilateral A (n = 3) and M (n = 15) with a mean age of 9.5 years (range 0.8-31.8) and treated with ocular prosthesis were included. Data on medical history, clinical examinations and management of ocular prosthesis were collected. Genetic screening with microarray and whole-exome sequencing targeting 121 A/M-related genes was performed. RESULTS A/M appeared isolated (seven cases) or as part of a syndromic condition (11 cases). In 4/16 patients, mutations were detected in TFAP2A, CHD7, FOXE3 and BCOR-genes. In one patient, a possibly causal microdeletion 10q11 was shown. Associated ocular anomalies such as cataract and cysts were found in 16 (89%) of the A/M eyes, and in nine (50%) ophthalmological findings were found in the fellow eyes. The median ages at which the conformer and ocular prosthesis first were initiated were 7.8 months and 1.5 years. 16/17 patients fulfilled satisfactory orbital growth and cosmetic results when treated with ocular prosthesis from an early age. CONCLUSION Based upon our findings, a multidisciplinary approach, including genetic assessment, is necessary to cover all aspects of A/M. Imaging, ultrasound and visual evoked potentials should be included. Early management is crucial for the outcome, in terms of non-ocular findings, vision in the fellow eye, and for facial cosmetic development.
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Affiliation(s)
- Rezhna Taha Najim
- Department of Clinical Neuroscience Institute of Neuroscience and Physiology Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Alexandra Topa
- Region Västra Götaland Department of Clinical Genetics and Genomics Sahlgrenska University Hospital Gothenburg Sweden
- Department of Laboratory Medicine Institute of Biomedicine Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Ylva Jugård
- Region Västra Götaland Department of Ophthalmology Hospital of Södra Älvsborg Borås Sweden
| | - Beatrice Casslén
- Department of Clinical Neuroscience Institute of Neuroscience and Physiology Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Marie Odersjö
- Region Västra Götaland Department of Otolaryngology Sahlgrenska University Hospital Gothenburg Sweden
| | - Marita Andersson Grönlund
- Department of Clinical Neuroscience Institute of Neuroscience and Physiology Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
- Region Västra Götaland Department of Ophthalmology Sahlgrenska University Hospital Mölndal Sweden
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25
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Casslén B, Jugård Y, Taha Najim R, Odersjö M, Topa A, Andersson Grönlund M. Visual function and quality of life in children and adolescents with anophthalmia and microphthalmia treated with ocular prosthesis. Acta Ophthalmol 2020; 98:662-670. [PMID: 32356375 DOI: 10.1111/aos.14424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 03/09/2020] [Indexed: 12/12/2022]
Abstract
PURPOSE To evaluate health-related quality of life (HR-QoL), vision-related (VR-)QoL and perceptual visual dysfunction (PVD) among individuals with anophthalmia (A) and microphthalmia (M) treated with ocular prosthesis. METHODS The study comprised 15 individuals (mean age 6.6 years; range 1.7-14.1) with unilateral A or M. Three validated instruments measuring HR-QoL and VR-QoL were used: The Pediatric QoL Inventory (PedsQL), consisting of physical and psychosocial self-report and parent-proxy report (2-18 years); Children's Visual Function Questionnaire (CVFQ); and Effects of Youngsters' Eyesight on Quality of Life (EYE-Q). Perceptual visual dysfunctions (PVDs) were assessed by history taking according to a specific protocol. RESULTS A/M children and their parents showed low HR-QoL scores (PedsQL total score: 66.3; 69.6) compared with controls (83.0; 87.61) (p = 0.0035 and <0.0001, respectively, unpaired t-test). No differences were found between A/M children and parents, but parents tended to underestimate their children's emotional state. A/M children with subnormal visual acuity (VA) for age scored lower in physical health compared with A/M children with normal VA (p = 0.03, Mann-Whitney U-test). No significant VR-QoL differences between A/M children and references or between A/M children with subnormal or normal VA for age were found. More A/M children than controls exhibited PVDs in ≥1 area (7/11 versus 4/118; p < 0.0001, Fisher's exact test). CONCLUSION A/M individuals show poor HR-QoL and increased PVDs. No difference in QoL was found between children and parents, though the children tended to score lower in emotional well-being. A/M children with subnormal VA showed lower physical health score. These problems indicate the necessity of a thorough multidisciplinary assessment and follow-up of children with A/M.
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Affiliation(s)
- Beatrice Casslén
- Department of Clinical Neuroscience Institute of Neuroscience and Physiology Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Ylva Jugård
- Department of Ophthalmology Södra Älvsborg Hospital Region Västra Götaland Borås Sweden
| | - Rezhna Taha Najim
- Department of Clinical Neuroscience Institute of Neuroscience and Physiology Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Marie Odersjö
- Department of Otolaryngology Sahlgrenska University Hospital Region Västra Götaland Gothenburg Sweden
| | - Alexandra Topa
- Department of Clinical Genetics and Genomics Sahlgrenska University Hospital Region Västra Götaland Gothenburg Sweden
- Department of Laboratory Medicine Institute of Biomedicine Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
| | - Marita Andersson Grönlund
- Department of Clinical Neuroscience Institute of Neuroscience and Physiology Sahlgrenska Academy University of Gothenburg Gothenburg Sweden
- Department of Ophthalmology Sahlgrenska University Hospital Region Västra Götaland Mölndal Sweden
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26
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Wawrocka A, Walczak-Sztulpa J, Pawlak M, Gotz-Wieckowska A, Krawczynski MR. Non-syndromic anophthalmia/microphthalmia can be caused by a PORCN variant inherited in X-linked recessive manner. Am J Med Genet A 2020; 185:250-255. [PMID: 33111437 DOI: 10.1002/ajmg.a.61938] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 09/25/2020] [Accepted: 10/01/2020] [Indexed: 11/10/2022]
Abstract
Anophthalmia and microphthalmia (A/M) represent severe developmental ocular malformations, corresponding, respectively, to absent eyeball or reduced size of the eye. Both anophthalmia and microphthalmia may occur in isolation or as part of a syndrome. Genetic heterogeneity has been demonstrated, and many genes have been reported to be associated with A/M. The advances in high-throughput sequencing have proven highly effective in defining the molecular basis of A/M. Nevertheless, there are still many patients with unsolved genetic background of the disease, who pose a significant challenge in the molecular diagnostics of A/M. Here we describe a family, with three males affected with the non-syndromic A/M. Whole exome-sequencing performed in Patient 1, revealed the presence of a novel probably pathogenic variant c.734A>G, (p.[Tyr245Cys]) in the PORCN gene. Pedigree analysis and segregation of the identified variant in the family confirmed the X-linked recessive pattern of inheritance. This is the first report of X-linked recessive non-syndromic A/M. Until now, pathogenic variants in the PORCN gene have been identified in the patients with Goltz syndrome, but they were inherited in X-linked dominant mode. The ocular phenotype is the only finding observed in the patients, which allows to exclude the diagnosis of Goltz syndrome.
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Affiliation(s)
- Anna Wawrocka
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland
| | | | - Marta Pawlak
- Department of Ophthalmology, Poznan University of Medical Sciences, Poznan, Poland
| | - Anna Gotz-Wieckowska
- Department of Ophthalmology, Poznan University of Medical Sciences, Poznan, Poland
| | - Maciej R Krawczynski
- Department of Medical Genetics, Poznan University of Medical Sciences, Poznan, Poland.,Centers for Medical Genetics GENESIS, Poznan, Poland
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27
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Islam F, Htun S, Lai LW, Krall M, Poranki M, Martin PM, Sobreira N, Wohler ES, Yu J, Moore AT, Slavotinek AM. Exome sequencing in patients with microphthalmia, anophthalmia, and coloboma (MAC) from a consanguineous population. Clin Genet 2020; 98:499-506. [PMID: 32799327 DOI: 10.1111/cge.13830] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Revised: 08/08/2020] [Accepted: 08/10/2020] [Indexed: 12/13/2022]
Abstract
Next-generation sequencing strategies have resulted in mutation detection rates of 21% to 61% in small cohorts of patients with microphthalmia, anophthalmia and coloboma (MAC), but despite progress in identifying novel causative genes, many patients remain without a genetic diagnosis. We studied a cohort of 19 patients with MAC who were ascertained from a population with high rates of consanguinity. Using single nucleotide polymorphism (SNP) arrays and whole exome sequencing (WES), we identified one pathogenic variant in TENM3 in a patient with cataracts in addition to MAC. We also detected novel variants of unknown significance in genes that have previously been associated with MAC, including KIF26B, MICU1 and CDON, and identified variants in candidate genes for MAC from the Wnt signaling pathway, comprising LRP6, WNT2B and IQGAP1, but our findings do not prove causality. Plausible variants were not found for many of the cases, indicating that our current understanding of the pathogenesis of MAC, a highly heterogeneous group of ocular defects, remains incomplete.
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Affiliation(s)
- Farrah Islam
- Department of Ophthalmology, Al-Shifa Eye Trust Hospital, Rawalpindi, Pakistan
| | - Stephanie Htun
- Division of Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
| | - Li-Wen Lai
- Department of Pathology, University of Arizona, Tucson, Arizona, USA
| | - Max Krall
- Division of Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
| | - Menitha Poranki
- Division of Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
| | - Pierre-Marie Martin
- Institute of Human Genetics, University of California San Francisco, San Francisco, California, USA
| | - Nara Sobreira
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Elizabeth S Wohler
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Jingwei Yu
- Department of Laboratory Medicine, University of California San Francisco, San Francisco, California, USA
| | - Anthony T Moore
- Dept. Ophthalmology, University of California San Francisco, San Francisco, California, USA
| | - Anne M Slavotinek
- Division of Genetics, Department of Pediatrics, University of California San Francisco, San Francisco, California, USA
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28
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Eintracht J, Toms M, Moosajee M. The Use of Induced Pluripotent Stem Cells as a Model for Developmental Eye Disorders. Front Cell Neurosci 2020; 14:265. [PMID: 32973457 PMCID: PMC7468397 DOI: 10.3389/fncel.2020.00265] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 07/28/2020] [Indexed: 12/15/2022] Open
Abstract
Approximately one-third of childhood blindness is attributed to developmental eye disorders, of which 80% have a genetic cause. Eye morphogenesis is tightly regulated by a highly conserved network of transcription factors when disrupted by genetic mutations can result in severe ocular malformation. Human-induced pluripotent stem cells (hiPSCs) are an attractive tool to study early eye development as they are more physiologically relevant than animal models, can be patient-specific and their use does not elicit the ethical concerns associated with human embryonic stem cells. The generation of self-organizing hiPSC-derived optic cups is a major advancement to understanding mechanisms of ocular development and disease. Their development in vitro has been found to mirror that of the human eye and these early organoids have been used to effectively model microphthalmia caused by a VSX2 variant. hiPSC-derived optic cups, retina, and cornea organoids are powerful tools for future modeling of disease phenotypes and will enable a greater understanding of the pathophysiology of many other developmental eye disorders. These models will also provide an effective platform for identifying molecular therapeutic targets and for future clinical applications.
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Affiliation(s)
| | - Maria Toms
- UCL Institute of Ophthalmology, London, United Kingdom.,The Francis Crick Institute, London, United Kingdom
| | - Mariya Moosajee
- UCL Institute of Ophthalmology, London, United Kingdom.,The Francis Crick Institute, London, United Kingdom.,Moorfields Eye Hospital NHS Foundation Trust, London, United Kingdom.,Great Ormond Street Hospital for Children NHS Foundation Trust, London, United Kingdom
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29
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The Pathogenesis and Treatment of Complications in Nanophthalmos. J Ophthalmol 2020; 2020:6578750. [PMID: 32765903 PMCID: PMC7387986 DOI: 10.1155/2020/6578750] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 06/09/2020] [Accepted: 07/01/2020] [Indexed: 11/17/2022] Open
Abstract
Microphthalmos is a type of developmental disorder ophthalmopathy, which can occur isolated or combined with other ocular malformations and can occur secondary to a systemic syndrome. Nanophthalmos is one of the clinical phenotypes of microphthalmos. Due to the special and complex structure of nanophthalmic eyes, the disorder is often associated with many complications, including high hyperopia, angle-closure glaucoma, and uveal effusion syndrome. The management of these complications is challenging, and conventional therapeutic methods are often ineffective in treating them. The purpose of this paper was to review the concept of nanophthalmos and present the latest progress in the study of the pathogenesis and treatment of its complications. As it is considerably challenging for ophthalmologists to prevent or treat these nanophthalmos complications, timely diagnosis and a suitable clinical treatment plan are vital to ensure that nanophthalmos patients are treated and managed effectively.
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30
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Eintracht J, Corton M, FitzPatrick D, Moosajee M. CUGC for syndromic microphthalmia including next-generation sequencing-based approaches. Eur J Hum Genet 2020; 28:679-690. [PMID: 31896778 PMCID: PMC7171178 DOI: 10.1038/s41431-019-0565-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 11/26/2019] [Accepted: 12/03/2019] [Indexed: 01/29/2023] Open
Affiliation(s)
| | - Marta Corton
- Department of Genetics, IIS-University Hospital Fundación Jiménez Díaz-CIBERER, Madrid, Spain
| | | | - Mariya Moosajee
- UCL Institute of Ophthalmology, London, UK.
- Moorfields Eye Hospital NHS Foundation Trust, London, UK.
- Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
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31
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Harding P, Brooks BP, FitzPatrick D, Moosajee M. Anophthalmia including next-generation sequencing-based approaches. Eur J Hum Genet 2020; 28:388-398. [PMID: 31358957 PMCID: PMC7029013 DOI: 10.1038/s41431-019-0479-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 06/06/2019] [Accepted: 07/16/2019] [Indexed: 11/09/2022] Open
Abstract
Name of the disease (synonyms) See Table 1, Column 1-"Name of disease" and Column 2-"Alternative names". OMIM# of the disease See Table 1, Column 3-"OMIM# of the disease". Name of the analysed genes or DNA/chromosome segments and OMIM# of the gene(s) Core genes (irrespective of being tested by Sanger sequencing or next-generation sequencing): See Table 1, Column 4-"Cytogenetic location", Column 5-"Associated gene(s)" and Column 6-"OMIM# of associated gene(s)". Additional genes (if tested by next-generation sequencing, including Whole exome/genome sequencing and panel sequencing): See Table 2, Column 1-"Gene", Column 2-"Alternative names", Column 3-"OMIM# of gene" and Column 4-"Cytogenetic location". Review of the analytical and clinical validity as well as of the clinical utility of DNA-based testing for mutations in the gene(s) in diagnostic, predictive and prenatal settings, and for risk assessment in relatives.
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Affiliation(s)
| | - Brian P Brooks
- Ophthalmic Genetics & Visual Function Branch, National Eye Institute, Bethesda, MD, USA
| | | | - Mariya Moosajee
- UCL Institute of Ophthalmology, London, UK. .,Moorfields Eye Hospital NHS Foundation Trust, London, UK. .,Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
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32
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Wawrocka A, Walczak-Sztulpa J, Bukowska-Olech E, Jamsheer A, Jaworski M, Jaworski P, Krawczynski MR. Two sisters with microphthalmia and anterior segment dysgenesis secondary to a PAX6 pathogenic variant with clinically healthy parents: a case of gonadal mosaicism? Jpn J Ophthalmol 2020; 64:134-139. [DOI: 10.1007/s10384-020-00715-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Accepted: 12/09/2019] [Indexed: 01/19/2023]
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33
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Paris JM, Letko A, Häfliger IM, Švara T, Gombač M, Klinc P, Škibin A, Pogorevc E, Drögemüller C. A de novo variant in OTX2 in a lamb with otocephaly. Acta Vet Scand 2020; 62:5. [PMID: 31969185 PMCID: PMC6977343 DOI: 10.1186/s13028-020-0503-z] [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: 10/31/2019] [Accepted: 01/13/2020] [Indexed: 12/03/2022] Open
Abstract
Background Otocephaly is a rare lethal malformation of the first branchial arch. While the knowledge on the causes of otocephaly in animals is limited, different syndromic forms in man are associated with variants of the PRRX1 and OTX2 genes. Case presentation A stillborn male lamb of the Istrian Pramenka sheep breed showed several congenital craniofacial anomalies including microstomia, agnathia, aglossia, and synotia. In addition, the lamb had a cleft palate, a small opening in the ventral neck region, a cystic oesophagus and two hepatic cysts. The brain was normally developed despite the deformed shape of the head. Taken together the findings led to a diagnosis of otocephaly. Whole-genome sequencing was performed from DNA of the affected lamb and both parents revealing a heterozygous single nucleotide variant in the OTX2 gene (Chr7: 71478714G > A). The variant was absent in both parents and therefore due to a de novo mutation event. It was a nonsense variant, XM_015097088.2:c.265C > T; which leads to an early premature stop codon and is predicted to truncate more than 70% of the OTX2 open reading frame (p.Arg89*). Conclusions The genetic findings were consistent with the diagnosis of the otocephaly and provide strong evidence that the identified loss-of-function variant is pathogenic due to OTX2 haploinsufficiency. The benefits of trio-based whole-genome sequencing as an emerging tool in veterinary pathology to confirm diagnosis are highlighted.
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34
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Harding P, Moosajee M. The Molecular Basis of Human Anophthalmia and Microphthalmia. J Dev Biol 2019; 7:jdb7030016. [PMID: 31416264 PMCID: PMC6787759 DOI: 10.3390/jdb7030016] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 08/08/2019] [Accepted: 08/08/2019] [Indexed: 12/16/2022] Open
Abstract
Human eye development is coordinated through an extensive network of genetic signalling pathways. Disruption of key regulatory genes in the early stages of eye development can result in aborted eye formation, resulting in an absent eye (anophthalmia) or a small underdeveloped eye (microphthalmia) phenotype. Anophthalmia and microphthalmia (AM) are part of the same clinical spectrum and have high genetic heterogeneity, with >90 identified associated genes. By understanding the roles of these genes in development, including their temporal expression, the phenotypic variation associated with AM can be better understood, improving diagnosis and management. This review describes the genetic and structural basis of eye development, focusing on the function of key genes known to be associated with AM. In addition, we highlight some promising avenues of research involving multiomic approaches and disease modelling with induced pluripotent stem cell (iPSC) technology, which will aid in developing novel therapies.
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Affiliation(s)
| | - Mariya Moosajee
- UCL Institute of Ophthalmology, London EC1V 9EL, UK.
- Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK.
- Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK.
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35
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Calvas P, Traboulsi EI, Ragge N. Through the looking glass: eye anomalies in the age of molecular science. Hum Genet 2019; 138:795-798. [PMID: 31392423 DOI: 10.1007/s00439-019-02056-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Accepted: 08/01/2019] [Indexed: 11/29/2022]
Affiliation(s)
- Patrick Calvas
- INSERM U1056, Centre de Référence des Anomalies Rares en Génétique Ophtalmologique, Service de Génétique Médicale, Centre Hospitalier Universitaire de Toulouse, Université de Toulouse, Toulouse, France
| | - Elias I Traboulsi
- Center for Genetic Eye Diseases/i32, Cole Eye Institute, The Cleveland Clinic, 9500 Euclid Ave, Cleveland, OH, 44195, USA
| | - Nicola Ragge
- Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, OX3 0BP, UK. .,West Midlands Regional Clinical Genetics Service and Birmingham Health Partners, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, B15 2TG, UK.
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Angelozzi M, Lefebvre V. SOXopathies: Growing Family of Developmental Disorders Due to SOX Mutations. Trends Genet 2019; 35:658-671. [PMID: 31288943 DOI: 10.1016/j.tig.2019.06.003] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 06/12/2019] [Accepted: 06/17/2019] [Indexed: 12/15/2022]
Abstract
The SRY-related (SOX) transcription factor family pivotally contributes to determining cell fate and identity in many lineages. Since the original discovery that SRY deletions cause sex reversal, mutations in half of the 20 human SOX genes have been associated with rare congenital disorders, henceforward called SOXopathies. Mutations are generally de novo, heterozygous, and inactivating, revealing gene haploinsufficiency, but other types, including duplications, have been reported too. Missense variants primarily target the HMG domain, the SOX hallmark that mediates DNA binding and bending, nuclear trafficking, and protein-protein interactions. We here review key clinical and molecular features of SOXopathies and discuss the prospect that the disease family likely involves more SOX genes and larger clinical and genetic spectrums than currently appreciated.
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Affiliation(s)
- Marco Angelozzi
- Department of Surgery/Division of Orthopaedic Surgery, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA
| | - Véronique Lefebvre
- Department of Surgery/Division of Orthopaedic Surgery, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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Ju YT, Pan YT, Tu CF, Hsiao J, Lin YH, Yu PJ, Yu PH, Chi CH, Liu IL. Growth and Behavior of Congenitally Anophthalmic Lee-Sung Pigs. Comp Med 2019; 69:212-220. [PMID: 31171049 DOI: 10.30802/aalas-cm-18-000095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Circadian rhythm is usually regulated by the environmental light-dark cycle. Congenitally anophthalmic miniature pigs provide a valuable model for the study of factors affecting circadian rhythms in the absence of visual exposure to the light-dark cycle. This study investigated the growth and daily behavior patterns of Lee-Sung pigs with congenital anophthalmia. Growth in 5 Lee-Sung pigs (LSP) with congenital anophthalmia (LSP-A) and 10 normally developed pigs (LSP-N) was assessed when they were 1 through 6 mo old. Behavioral studies using digital video recording were completed in 6 sexually mature LSP (3 LSP-A and 3 LSP-N). MRI showed that LSP-A lose their vision because of a lack of retinal input and optic chiasm development. LSP-N and LSP-A did not differ in body weight or size at 2, 4, and 6 mo of age. Behavior and activity pattern studies showed that both LSP-A and LSP-N were active mainly during daylight, but LSP-A spent significantly more time exploring their environment during the day (28%) and night (10%) than did LSP-N. This study revealed that growth performance was similar between LSP-A and normal pigs, but their behavior and activity patterns differed. LSP-A showed circadian rhythm abnormalities similar to those in blind humans. This study provides basic data on LSP-A as a model for studying compensatory cross-modal brain plasticity and hormone regulation in the absence of retinal input is deficient and for understanding the role of circadian rhythm regulation.
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Affiliation(s)
- Yu-Ten Ju
- Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Yu-Ting Pan
- Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan
| | | | - Jan Hsiao
- Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Yi-Hsuan Lin
- Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Pei-Ju Yu
- Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Pin-Huan Yu
- Institute of Veterinary Clinical Science, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - Chau-Hwa Chi
- Institute of Veterinary Clinical Science, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
| | - I-Li Liu
- Institute of Veterinary Clinical Science, School of Veterinary Medicine, National Taiwan University, Taipei, Taiwan
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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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