-
Eye (London, England) Aug 2021Typical ocular coloboma is caused by defective closure of the embryonal fissure. The occurrence of coloboma can be sporadic, hereditary (known or unknown gene defects)... (Review)
Review
Typical ocular coloboma is caused by defective closure of the embryonal fissure. The occurrence of coloboma can be sporadic, hereditary (known or unknown gene defects) or associated with chromosomal abnormalities. Ocular colobomata are more often associated with systemic abnormalities when caused by chromosomal abnormalities. The ocular manifestations vary widely. At one extreme, the eye is hardly recognisable and non-functional-having been compressed by an orbital cyst, while at the other, one finds minimalistic involvement that hardly affects the structure and function of the eye. In the fundus, the variability involves the size of the coloboma (anteroposterior and transverse extent) and the involvement of the optic disc and fovea. The visual acuity is affected when coloboma involves disc and fovea, or is complicated by occurrence of retinal detachment, choroidal neovascular membrane, cataract, amblyopia due to uncorrected refractive errors, etc. While the basic birth anomaly cannot be corrected, most of the complications listed above are correctable to a great extent. Current day surgical management of coloboma-related retinal detachments has evolved to yield consistently good results. Cataract surgery in these eyes can pose a challenge due to a combination of microphthalmos and relatively hard lenses, resulting in increased risk of intra-operative complications. Prophylactic laser retinopexy to the border of choroidal coloboma appears to be an attractive option for reducing risk of coloboma-related retinal detachment. However, a majority of the eyes have the optic disc within the choroidal coloboma, thus making it difficult to safely administer a complete treatment.
Topics: Coloboma; Humans; Microphthalmos; Optic Disk; Retinal Detachment; Visual Acuity
PubMed: 33746210
DOI: 10.1038/s41433-021-01501-5 -
The Journal of Pathology Jun 2022GPNMB (glycoprotein nonmetastatic B) and other TFE3/TFEB transcriptional targets have been proposed as markers for microphthalmia (MiT) translocation renal cell...
GPNMB (glycoprotein nonmetastatic B) and other TFE3/TFEB transcriptional targets have been proposed as markers for microphthalmia (MiT) translocation renal cell carcinomas (tRCCs). We recently demonstrated that constitutive mTORC1 activation via TSC1/2 loss leads to increased activity of TFE3/TFEB, suggesting that the pathogenesis and molecular markers for tRCCs and TSC1/2-associated tumors may be overlapping. We examined GPNMB expression in human kidney and angiomyolipoma (AML) cell lines with TSC2 and/or TFE3/TFEB loss produced using CRISPR-Cas9 genome editing as well as in a mouse model of Tsc2 inactivation-driven renal tumorigenesis. Using an automated immunohistochemistry (IHC) assay for GPNMB, digital image analysis was employed to quantitatively score expression in clear cell RCC (ccRCC, n = 87), papillary RCC (papRCC, n = 53), chromophobe RCC (chRCC, n = 34), oncocytoma (n = 4), TFE3- or TFEB-driven tRCC (n = 56), eosinophilic solid and cystic RCC (ESC, n = 6), eosinophilic vacuolated tumor (EVT, n = 4), and low-grade oncocytic tumor (LOT, n = 3), as well as AML (n = 29) and perivascular epithelioid cell tumors (PEComas, n = 8). In cell lines, GPNMB was upregulated following TSC2 loss in a MiT/TFE- and mTORC1-dependent fashion. Renal tumors in Tsc2 A/J mice showed upregulation of GPNMB compared with normal kidney. Mean GPNMB expression was significantly higher in tRCC than in ccRCC (p < 0.0001), papRCC (p < 0.0001), and chRCC (p < 0.0001). GPNMB expression in TSC1/2/MTOR alteration-associated renal tumors (including ESC, LOT, AML, and PEComa) was comparable to that in tRCC. The immunophenotype of tRCC and TSC1/2/MTOR alteration-associated renal tumors is highly overlapping, likely due to the increased activity of TFE3/TFEB in both, revealing an important caveat regarding the use of TFE3/TFEB-transcriptional targets as diagnostic markers. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Topics: Animals; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Biomarkers, Tumor; Carcinoma, Renal Cell; Eye Proteins; Female; Humans; Kidney Neoplasms; Leukemia, Myeloid, Acute; Male; Mechanistic Target of Rapamycin Complex 1; Membrane Glycoproteins; Mice; Microphthalmos; Perivascular Epithelioid Cell Neoplasms; TOR Serine-Threonine Kinases; Transcription Factors; Translocation, Genetic; Tuberous Sclerosis
PubMed: 35072947
DOI: 10.1002/path.5875 -
Eye (London, England) Jul 2019To report the customized approach of patients with anophthalmia or microphthalmia with bespoke ocular prosthesis.
PURPOSE
To report the customized approach of patients with anophthalmia or microphthalmia with bespoke ocular prosthesis.
METHODS
Retrospective analysis of case series.
RESULTS
The study included cases with anophthalmia with upper eyelid deformity (one patient), microphthalmia and contralateral corectopia (one patient), microphthalmia with contralateral corneal graft (one patient), and congenital clinical anophthalmia with contralateral sclerocornea (one patient). Using techniques of embedded autologous hair and coating of adhesive pigment emulsion in the ocular prosthesis, the physical appearance of, respectively, an upper eyelid, corectopia, corneal graft, and sclerocornea was reproduced.
CONCLUSION
Tailoring the ocular prosthesis to the distinct condition of the anophthalmic socket and contralateral eye adds to the success of rehabilitative prosthetic treatment of the patient.
Topics: Adult; Aged; Anophthalmos; Eye, Artificial; Female; Humans; Infant; Male; Microphthalmos; Middle Aged; Prosthesis Design
PubMed: 30837709
DOI: 10.1038/s41433-019-0385-3 -
Indian Journal of Ophthalmology Mar 2016Oculodentodigital dysplasia is a rare, autosomal dominant disorder with high penetrance and variable expressivity, caused by mutations in the connexin 43 or gap junction...
Oculodentodigital dysplasia is a rare, autosomal dominant disorder with high penetrance and variable expressivity, caused by mutations in the connexin 43 or gap junction protein alpha-1 gene. It has been diagnosed in fewer than 300 people worldwide with an incidence of around 1 in 10 million. It affects many parts of the body, particularly eyes (oculo), teeth (dento), and fingers and/or toes (digital). The common clinical features include facial dysmorphism with thin nose, microphthalmia, syndactyly, tooth anomalies such as enamel hypoplasia, anodontia, microdontia, early tooth loss and conductive deafness. Other less common features are abnormalities of the skin and its appendages, such as brittle nails, sparse hair, and neurological abnormalities. To prevent this syndrome from being overlooked, awareness of possible symptoms is necessary. Early recognition can prevent blindness, dental problems and learning disabilities. Described here is the case of a 21-year-old male who presented to the ophthalmology outpatient department with a complaint of bilateral progressive loss of vision since childhood.
Topics: Abnormalities, Multiple; Craniofacial Abnormalities; Eye Abnormalities; Foot Deformities, Congenital; Humans; Male; Microphthalmos; Syndactyly; Tooth Abnormalities; Vision, Low; Visual Acuity; Young Adult
PubMed: 27146935
DOI: 10.4103/0301-4738.180191 -
Journal of Medical Genetics Aug 1993A new classification of microphthalmos and coloboma is proposed to bring order to the complexity of clinical and aetiological heterogeneity of these conditions. A... (Review)
Review
A new classification of microphthalmos and coloboma is proposed to bring order to the complexity of clinical and aetiological heterogeneity of these conditions. A phenotypic classification is presented which may help the clinician to give a systematic description of the anomalies. The phenotype does not predict the aetiology but a systematic description of ocular and systemic anomalies improves syndrome identification. There are two major classes, total and partial microphthalmos, and a subclassification which follows the embryology of the anomalies. The aetiological classification consists of three classes: (1) genetic (monogenic and chromosomal), (2) prenatally acquired (teratological agents and intrauterine deformations), and (3) associations. Genetic disorders give rise to malformations; prenatally acquired anomalies are disruptions or deformations. The aetiological classification can be applied to other congenital birth defects and improves counselling of families. Recurrence risks vary considerably between the classes.
Topics: Coloboma; Humans; Microphthalmos; Phenotype
PubMed: 8411053
DOI: 10.1136/jmg.30.8.664 -
Nature Communications Dec 2022Microphthalmia transcription factor (MiT) family translocation renal cell carcinoma (tRCC) is a rare type of kidney cancer, which is not well characterized. Here we show...
Microphthalmia transcription factor (MiT) family translocation renal cell carcinoma (tRCC) is a rare type of kidney cancer, which is not well characterized. Here we show the comprehensive proteogenomic analysis of tRCC tumors and normal adjacent tissues to elucidate the molecular landscape of this disease. Our study reveals that defective DNA repair plays an important role in tRCC carcinogenesis and progression. Metabolic processes are markedly dysregulated at both the mRNA and protein levels. Proteomic and phosphoproteome data identify mTOR signaling pathway as a potential therapeutic target. Moreover, molecular subtyping and immune infiltration analysis characterize the inter-tumoral heterogeneity of tRCC. Multi-omic integration reveals the dysregulation of cellular processes affected by genomic alterations, including oxidative phosphorylation, autophagy, transcription factor activity, and proteasome function. This study represents a comprehensive proteogenomic analysis of tRCC, providing valuable insights into its biological mechanisms, disease diagnosis, and prognostication.
Topics: Humans; Carcinoma, Renal Cell; Proteogenomics; Transcription Factors; Microphthalmos; Proteomics; Kidney Neoplasms; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors; Translocation, Genetic
PubMed: 36470859
DOI: 10.1038/s41467-022-34460-w -
The British Journal of Ophthalmology Dec 1946
Topics: Humans; Microphthalmos; Retina; Retinal Detachment
PubMed: 18170283
DOI: 10.1136/bjo.30.12.709 -
Genes Feb 2020Facioscapulohumeral muscular dystrophy (FSHD) has been associated with the genetic and epigenetic molecular features of the CpG-rich D4Z4 repeat tandem array at 4q35.... (Review)
Review
Facioscapulohumeral muscular dystrophy (FSHD) has been associated with the genetic and epigenetic molecular features of the CpG-rich D4Z4 repeat tandem array at 4q35. Reduced DNA methylation of D4Z4 repeats is considered part of the FSHD mechanism and has been proposed as a reliable marker in the FSHD diagnostic procedure. We considered the assessment of D4Z4 DNA methylation status conducted on distinct cohorts using different methodologies. On the basis of the reported results we conclude that the percentage of DNA methylation detected at D4Z4 does not correlate with the disease status. Overall, data suggest that in the case of FSHD1, D4Z4 hypomethylation is a consequence of the chromatin structure present in the contracted allele, rather than a proxy of its function. Besides, CpG methylation at D4Z4 DNA is reduced in patients presenting diseases unrelated to muscle progressive wasting, like Bosma Arhinia and Microphthalmia syndrome, a developmental disorder, as well as ICF syndrome. Consistent with these observations, the analysis of epigenetic reprogramming at the D4Z4 locus in human embryonic and induced pluripotent stem cells indicate that other mechanisms, independent from the repeat number, are involved in the control of the epigenetic structure at D4Z4.
Topics: Choanal Atresia; CpG Islands; DNA Methylation; Epigenesis, Genetic; Face; Homeodomain Proteins; Humans; Microphthalmos; Muscle Weakness; Muscular Dystrophy, Facioscapulohumeral; Nose; Primary Immunodeficiency Diseases; Protein Processing, Post-Translational; Tandem Repeat Sequences
PubMed: 32121044
DOI: 10.3390/genes11030258 -
Orphanet Journal of Rare Diseases Nov 2007Anophthalmia and microphthalmia describe, respectively, the absence of an eye and the presence of a small eye within the orbit. The combined birth prevalence of these... (Review)
Review
Anophthalmia and microphthalmia describe, respectively, the absence of an eye and the presence of a small eye within the orbit. The combined birth prevalence of these conditions is up to 30 per 100,000 population, with microphthalmia reported in up to 11% of blind children. High-resolution cranial imaging, post-mortem examination and genetic studies suggest that these conditions represent a phenotypic continuum. Both anophthalmia and microphthalmia may occur in isolation or as part of a syndrome, as in one-third of cases. Anophthalmia/microphthalmia have complex aetiology with chromosomal, monogenic and environmental causes identified. Chromosomal duplications, deletions and translocations are implicated. Of monogenic causes only SOX2 has been identified as a major causative gene. Other linked genes include PAX6, OTX2, CHX10 and RAX. SOX2 and PAX6 mutations may act through causing lens induction failure. FOXE3 mutations, associated with lens agenesis, have been observed in a few microphthalmic patients. OTX2, CHX10 and RAX have retinal expression and may result in anophthalmia/microphthalmia through failure of retinal differentiation. Environmental factors also play a contributory role. The strongest evidence appears to be with gestational-acquired infections, but may also include maternal vitamin A deficiency, exposure to X-rays, solvent misuse and thalidomide exposure. Diagnosis can be made pre- and post-natally using a combination of clinical features, imaging (ultrasonography and CT/MR scanning) and genetic analysis. Genetic counselling can be challenging due to the extensive range of genes responsible and wide variation in phenotypic expression. Appropriate counselling is indicated if the mode of inheritance can be identified. Differential diagnoses include cryptophthalmos, cyclopia and synophthalmia, and congenital cystic eye. Patients are often managed within multi-disciplinary teams consisting of ophthalmologists, paediatricians and/or clinical geneticists, especially for syndromic cases. Treatment is directed towards maximising existing vision and improving cosmesis through simultaneous stimulation of both soft tissue and bony orbital growth. Mild to moderate microphthalmia is managed conservatively with conformers. Severe microphthalmia and anophthalmia rely upon additional remodelling strategies of endo-orbital volume replacement (with implants, expanders and dermis-fat grafts) and soft tissue reconstruction. The potential for visual development in microphthalmic patients is dependent upon retinal development and other ocular characteristics.
Topics: Anophthalmos; HMGB Proteins; Humans; Magnetic Resonance Imaging; Microphthalmos; Mutation; Prevalence; SOXB1 Transcription Factors; Transcription Factors; Vitamin A Deficiency
PubMed: 18039390
DOI: 10.1186/1750-1172-2-47 -
Clinical Genetics May 2020Nanophthalmos and posterior microphthalmos are ocular abnormalities in which both eyes are abnormally small, and typically associated with extreme hyperopia. We...
Nanophthalmos and posterior microphthalmos are ocular abnormalities in which both eyes are abnormally small, and typically associated with extreme hyperopia. We recruited 40 individuals from 13 kindreds with nanophthalmos or posterior microphthalmos, with 12 probands subjected to exome sequencing. Nine probands (69.2%) were assigned a genetic diagnosis, with variants in MYRF, TMEM98, MFRP, and PRSS56. Two of four PRSS56 families harbored the previously described c.1066dupC variant implicated in over half of all reported PRSS56 kindreds, with different surrounding haplotypes in each family suggesting a mutational hotspot. Individuals with a genetic diagnosis had shorter mean axial lengths and higher hyperopia than those without, with recessive forms associated with the most extreme phenotypes. These findings detail the genetic architecture of nanophthalmos and posterior microphthalmos in a cohort of predominantly European ancestry, their relative clinical phenotypes, and highlight the shared genetic architecture of rare and common disorders of refractive error.
Topics: Australia; Cohort Studies; Eye; Eye Diseases, Hereditary; Female; Frameshift Mutation; Glaucoma, Angle-Closure; Humans; Hyperopia; Male; Membrane Proteins; Microphthalmos; Pedigree; Serine Proteases; Transcription Factors
PubMed: 32052405
DOI: 10.1111/cge.13722