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Molecular Therapy : the Journal of the... Feb 2021Hereditary diseases are caused by mutations in genes, and more than 7,000 rare diseases affect over 30 million Americans. For more than 30 years, hundreds of researchers... (Review)
Review
Hereditary diseases are caused by mutations in genes, and more than 7,000 rare diseases affect over 30 million Americans. For more than 30 years, hundreds of researchers have maintained that genetic modifications would provide effective treatments for many inherited human diseases, offering durable and possibly curative clinical benefit with a single treatment. This review is limited to gene therapy using adeno-associated virus (AAV) because the gene delivered by this vector does not integrate into the patient genome and has a low immunogenicity. There are now five treatments approved for commercialization and currently available, i.e., Luxturna, Zolgensma, the two chimeric antigen receptor T cell (CAR-T) therapies (Yescarta and Kymriah), and Strimvelis (the gammaretrovirus approved for adenosine deaminase-severe combined immunodeficiency [ADA-SCID] in Europe). Dozens of other treatments are under clinical trials. The review article presents a broad overview of the field of therapy by in vivo gene transfer. We review gene therapy for neuromuscular disorders (spinal muscular atrophy [SMA]; Duchenne muscular dystrophy [DMD]; X-linked myotubular myopathy [XLMTM]; and diseases of the central nervous system, including Alzheimer's disease, Parkinson's disease, Canavan disease, aromatic l-amino acid decarboxylase [AADC] deficiency, and giant axonal neuropathy), ocular disorders (Leber congenital amaurosis, age-related macular degeneration [AMD], choroideremia, achromatopsia, retinitis pigmentosa, and X-linked retinoschisis), the bleeding disorder hemophilia, and lysosomal storage disorders.
Topics: Animals; Clinical Studies as Topic; Combined Modality Therapy; Dependovirus; Gene Expression; Genetic Diseases, Inborn; Genetic Therapy; Genetic Vectors; Humans; Organ Specificity; Treatment Outcome
PubMed: 33309881
DOI: 10.1016/j.ymthe.2020.12.007 -
Human Mutation Sep 2020We aimed to unravel the molecular genetic basis of inherited retinal degeneration (IRD) in a comprehensive cohort of patients diagnosed in the largest center for IRD in...
We aimed to unravel the molecular genetic basis of inherited retinal degeneration (IRD) in a comprehensive cohort of patients diagnosed in the largest center for IRD in Germany. A cohort of 2,158 affected patients from 1,785 families diagnosed with IRD was analyzed by targeted next-generation sequencing (NGS). Patients with single-gene disorders (i.e., choroideremia and retinoschisis) were analyzed by Sanger sequencing and multiplex ligation-dependent probe amplification. Our study cohort accounts for ∼7% of the estimated 30,000 patients with IRD in Germany, thereby providing representative data for both the prevalence of IRDs and the mutation spectrum of IRD genes for the population in Germany. We achieved a molecular diagnostic rate of 35-95%, depending on the clinical entities, with a high detection rate for achromatopsia, retinoschisis, and choroideremia, and a low detection rate for central areolar choroidal dystrophy and macular dystrophy. A total of 1,161 distinct variants were identified, including 501 novel variants, reaffirming the known vast genetic heterogeneity of IRD in a mainly outbred European population. This study demonstrates the clinical utility of panel-based NGS in a large and highly heterogeneous cohort from an outbred population and for the first time gives a comprehensive representation of the genetic landscape of IRDs in Germany. The data are valuable and crucial for the scientific community and healthcare providers, but also for the pharmaceutical industry in the progressing field of personalized medicine and gene therapy.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Child; Child, Preschool; Cohort Studies; Female; Germany; High-Throughput Nucleotide Sequencing; Humans; Infant; Infant, Newborn; Male; Middle Aged; Phenotype; Retinal Dystrophies; Young Adult
PubMed: 32531858
DOI: 10.1002/humu.24064 -
Progress in Retinal and Eye Research May 2021X-linked retinopathies represent a significant proportion of monogenic retinal disease. They include progressive and stationary conditions, with and without syndromic... (Review)
Review
X-linked retinopathies represent a significant proportion of monogenic retinal disease. They include progressive and stationary conditions, with and without syndromic features. Many are X-linked recessive, but several exhibit a phenotype in female carriers, which can help establish diagnosis and yield insights into disease mechanisms. The presence of affected carriers can misleadingly suggest autosomal dominant inheritance. Some disorders (such as RPGR-associated retinopathy) show diverse phenotypes from variants in the same gene and also highlight limitations of current genetic sequencing methods. X-linked disease frequently arises from loss of function, implying potential for benefit from gene replacement strategies. We review X-inactivation and X-linked inheritance, and explore burden of disease attributable to X-linked genes in our clinically and genetically characterised retinal disease cohort, finding correlation between gene transcript length and numbers of families. We list relevant genes and discuss key clinical features, disease mechanisms, carrier phenotypes and novel experimental therapies. We consider in detail the following: RPGR (associated with retinitis pigmentosa, cone and cone-rod dystrophy), RP2 (retinitis pigmentosa), CHM (choroideremia), RS1 (X-linked retinoschisis), NYX (complete congenital stationary night blindness (CSNB)), CACNA1F (incomplete CSNB), OPN1LW/OPN1MW (blue cone monochromacy, Bornholm eye disease, cone dystrophy), GPR143 (ocular albinism), COL4A5 (Alport syndrome), and NDP (Norrie disease and X-linked familial exudative vitreoretinopathy (FEVR)). We use a recently published transcriptome analysis to explore expression by cell-type and discuss insights from electrophysiology. In the final section, we present an algorithm for genes to consider in diagnosing males with non-syndromic X-linked retinopathy, summarise current experimental therapeutic approaches, and consider questions for future research.
Topics: Calcium Channels, L-Type; Eye Proteins; Female; Genes, X-Linked; Genetic Diseases, X-Linked; Humans; Male; Mutation; Night Blindness; Phenotype; Retinal Degeneration
PubMed: 32860923
DOI: 10.1016/j.preteyeres.2020.100898 -
The British Journal of Ophthalmology Apr 2020Macular dystrophies (MDs) consist of a heterogeneous group of disorders that are characterised by bilateral symmetrical central visual loss. Advances in genetic testing... (Review)
Review
Macular dystrophies (MDs) consist of a heterogeneous group of disorders that are characterised by bilateral symmetrical central visual loss. Advances in genetic testing over the last decade have led to improved knowledge of the underlying molecular basis. The developments in high-resolution multimodal retinal imaging have also transformed our ability to make accurate and more timely diagnoses and more sensitive quantitative assessment of disease progression, and allowed the design of optimised clinical trial endpoints for novel therapeutic interventions. The aim of this review was to provide an update on MDs, including Stargardt disease, Best disease, X-linked r etinoschisis, pattern dystrophy, Sorsby fundus dystrophy and autosomal dominant drusen. It highlights the range of innovations in retinal imaging, genotype-phenotype and structure-function associations, animal models of disease and the multiple treatment strategies that are currently in clinical trial or planned in the near future, which are anticipated to lead to significant changes in the management of patients with MDs.
Topics: Diagnostic Imaging; Humans; Macular Degeneration; Molecular Biology; Therapeutics
PubMed: 31704701
DOI: 10.1136/bjophthalmol-2019-315086 -
Progress in Retinal and Eye Research Sep 2023Myopic axial elongation is associated with various non-pathological changes. These include a decrease in photoreceptor cell and retinal pigment epithelium (RPE) cell... (Review)
Review
Myopic axial elongation is associated with various non-pathological changes. These include a decrease in photoreceptor cell and retinal pigment epithelium (RPE) cell density and retinal layer thickness, mainly in the retro-equatorial to equatorial regions; choroidal and scleral thinning pronounced at the posterior pole and least marked at the ora serrata; and a shift in Bruch's membrane opening (BMO) occurring in moderately myopic eyes and typically in the temporal/inferior direction. The BMO shift leads to an overhang of Bruch's membrane (BM) into the nasal intrapapillary compartment and BM absence in the temporal region (i.e., parapapillary gamma zone), optic disc ovalization due to shortening of the ophthalmoscopically visible horizontal disc diameter, fovea-optic disc distance elongation, reduction in angle kappa, and straightening/stretching of the papillomacular retinal blood vessels and retinal nerve fibers. Highly myopic eyes additionally show an enlargement of all layers of the optic nerve canal, elongation and thinning of the lamina cribrosa, peripapillary scleral flange (i.e., parapapillary delta zone) and peripapillary choroidal border tissue, and development of circular parapapillary beta, gamma, and delta zone. Pathological features of high myopia include development of macular linear RPE defects (lacquer cracks), which widen to round RPE defects (patchy atrophies) with central BM defects, macular neovascularization, myopic macular retinoschisis, and glaucomatous/glaucoma-like and non-glaucomatous optic neuropathy. BM thickness is unrelated to axial length. Including the change in eye shape from a sphere in emmetropia to a prolate (rotational) ellipsoid in myopia, the features may be explained by a primary BM enlargement in the retro-equatorial/equatorial region leading to axial elongation.
Topics: Humans; Axial Length, Eye; Myopia; Choroid; Optic Disk; Bruch Membrane; Tomography, Optical Coherence
PubMed: 36585290
DOI: 10.1016/j.preteyeres.2022.101156 -
Progress in Retinal and Eye Research May 2024Inherited retinal diseases (IRD) are a leading cause of blindness in the working age population and in children. The scope of this review is to familiarise clinicians... (Review)
Review
Phenotyping and genotyping inherited retinal diseases: Molecular genetics, clinical and imaging features, and therapeutics of macular dystrophies, cone and cone-rod dystrophies, rod-cone dystrophies, Leber congenital amaurosis, and cone dysfunction syndromes.
Inherited retinal diseases (IRD) are a leading cause of blindness in the working age population and in children. The scope of this review is to familiarise clinicians and scientists with the current landscape of molecular genetics, clinical phenotype, retinal imaging and therapeutic prospects/completed trials in IRD. Herein we present in a comprehensive and concise manner: (i) macular dystrophies (Stargardt disease (ABCA4), X-linked retinoschisis (RS1), Best disease (BEST1), PRPH2-associated pattern dystrophy, Sorsby fundus dystrophy (TIMP3), and autosomal dominant drusen (EFEMP1)), (ii) cone and cone-rod dystrophies (GUCA1A, PRPH2, ABCA4, KCNV2 and RPGR), (iii) predominant rod or rod-cone dystrophies (retinitis pigmentosa, enhanced S-Cone syndrome (NR2E3), Bietti crystalline corneoretinal dystrophy (CYP4V2)), (iv) Leber congenital amaurosis/early-onset severe retinal dystrophy (GUCY2D, CEP290, CRB1, RDH12, RPE65, TULP1, AIPL1 and NMNAT1), (v) cone dysfunction syndromes (achromatopsia (CNGA3, CNGB3, PDE6C, PDE6H, GNAT2, ATF6), X-linked cone dysfunction with myopia and dichromacy (Bornholm Eye disease; OPN1LW/OPN1MW array), oligocone trichromacy, and blue-cone monochromatism (OPN1LW/OPN1MW array)). Whilst we use the aforementioned classical phenotypic groupings, a key feature of IRD is that it is characterised by tremendous heterogeneity and variable expressivity, with several of the above genes associated with a range of phenotypes.
Topics: Humans; Cone-Rod Dystrophies; Eye Diseases, Hereditary; Genotype; Leber Congenital Amaurosis; Molecular Biology; Phenotype; Retinal Diseases
PubMed: 38278208
DOI: 10.1016/j.preteyeres.2024.101244 -
Progress in Retinal and Eye Research Nov 2022Besides cystoid macular edema due to a blood-retinal barrier breakdown, another type of macular cystoid spaces referred to as non-vasogenic cystoid maculopathies (NVCM)... (Review)
Review
Besides cystoid macular edema due to a blood-retinal barrier breakdown, another type of macular cystoid spaces referred to as non-vasogenic cystoid maculopathies (NVCM) may be detected on optical coherence tomography but not on fluorescein angiography. Various causes may disrupt retinal cell cohesion or impair retinal pigment epithelium (RPE) and Müller cell functions in the maintenance of retinal dehydration, resulting in cystoid spaces formation. Tractional causes include vitreomacular traction, epiretinal membranes and myopic foveoschisis. Surgical treatment does not always allow cystoid space resorption. In inherited retinal dystrophies, cystoid spaces may be part of the disease as in X-linked retinoschisis or enhanced S-cone syndrome, or occur occasionally as in bestrophinopathies, retinitis pigmentosa and allied diseases, congenital microphthalmia, choroideremia, gyrate atrophy and Bietti crystalline dystrophy. In macular telangiectasia type 2, cystoid spaces and cavitations do not depend on the fluid leakage from telangiectasia. Various causes affecting RPE function may result in NVCM such as chronic central serous chorioretinopathy and paraneoplastic syndromes. Non-exudative age macular degeneration may also be complicated by intraretinal cystoid spaces in the absence of fluorescein leakage. In these diseases, cystoid spaces occur in a context of retinal cell loss. Various causes of optic atrophy, including open-angle glaucoma, result in microcystoid spaces in the inner nuclear layer due to a retrograde transsynaptic degeneration. Lastly, drug toxicity may also induce cystoid maculopathy. Identifying NVCM on multimodal imaging, including fluorescein angiography if needed, allows guiding the diagnosis of the causative disease and choosing adequate treatment when available.
Topics: Humans; Glaucoma, Open-Angle; Macular Edema; Fluorescein Angiography; Macular Degeneration; Tomography, Optical Coherence; Retinal Telangiectasis
PubMed: 35927124
DOI: 10.1016/j.preteyeres.2022.101092 -
Klinische Monatsblatter Fur... Dec 2020This review article gives an overview of the epidemiology, relevant risk factors, clinical characteristics and the diagnostic approach of rhegmatogenous retinal... (Review)
Review
This review article gives an overview of the epidemiology, relevant risk factors, clinical characteristics and the diagnostic approach of rhegmatogenous retinal detachment. Rhegmatogenous retinal detachment is an ophthalmologic emergency needing immediate surgical treatment. Main risk factors are retinal tears, myopia and previous cataract surgery. For patients with symptoms of posterior vitreous detachment, indirect ophthalmoscopy under pupil dilatation is necessary to diagnose retinal tears or retinal detachment. Differential diagnoses are tractive or exudative forms of retinal detachment or retinoschisis.
Topics: Cataract Extraction; Humans; Retinal Detachment; Retinal Perforations; Risk Factors; Vitreous Detachment
PubMed: 33207382
DOI: 10.1055/a-1243-1363 -
Cold Spring Harbor Perspectives in... Sep 2023X-linked retinoschisis (XLRS) is an inherited vitreoretinal dystrophy causing visual impairment in males starting at a young age with an estimated prevalence of 1:5000... (Review)
Review
X-linked retinoschisis (XLRS) is an inherited vitreoretinal dystrophy causing visual impairment in males starting at a young age with an estimated prevalence of 1:5000 to 1:25,000. The condition was first observed in two affected brothers by Josef Haas in 1898 and is clinically diagnosed by characteristic intraretinal cysts arranged in a petaloid "spoke-wheel" pattern centered in the macula. When clinical electroretinogram (ERG) testing began in the 1960s, XLRS was noted to have a characteristic reduction of the dark-adapted b-wave amplitude despite normal or usually nearly normal a-wave amplitudes, which became known as the "electronegative ERG response" of XLRS disease. The causative gene, , was identified on the X-chromosome in 1997 and led to understanding the molecular and cellular basis of the condition, discerning the structure and function of the retinoschisin protein, and generating XLRS murine models. Along with parallel development of gene delivery vectors suitable for targeting retinal diseases, successful gene augmentation therapy was demonstrated by rescuing the XLRS phenotype in mouse. Two human phase I/II therapeutic XLRS gene augmentation studies were initiated; and although these did not yield definitive improvement in visual function, they gave significant new knowledge and experience, which positions the field for further near-term clinical testing with enhanced, next-generation gene therapy for XLRS patients.
Topics: Male; Humans; Animals; Mice; Retinoschisis; Mutation; Electroretinography; Phenotype; Genetic Therapy; Eye Proteins; Retina
PubMed: 36690462
DOI: 10.1101/cshperspect.a041288 -
Eye (London, England) Sep 2021First described by Gaucher and associates in 2008 in eyes with high myopia, dome-shaped maculopathy (DSM) is an anterior convex protrusion of the macula towards the... (Review)
Review
First described by Gaucher and associates in 2008 in eyes with high myopia, dome-shaped maculopathy (DSM) is an anterior convex protrusion of the macula towards the vitreous cavity observable on OCT. This seems to be related to a localized scleral thickness, which might be the result of regional variation in the scleral bio-mechanical properties and the process of emmetropization causing asymmetric scleral growth. The presence of DSM can be associated with an increased risk of complications. The clinical spectrum ranges from being asymptomatic to metamorphopsia and mild-to-moderate gradual visual loss over years. Visual impairment in DSM results from retinal pigment epithelial changes, sub-foveal serous detachment, retinoschisis and myopic choroidal neovascularization. In this review, we compile and review the available information on the pathophysiology, nomenclature, classification, clinical features including imaging, differential diagnosis, complications associated with DSM and the gaps in our understanding of this entity thus far.
Topics: Fluorescein Angiography; Humans; Macula Lutea; Macular Degeneration; Myopia, Degenerative; Retinal Diseases; Retrospective Studies; Tomography, Optical Coherence; Visual Acuity
PubMed: 33875828
DOI: 10.1038/s41433-021-01518-w