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Having devoted over 35 years of my professional life to various projects on choroideremia (CHM), I began to reflect on the many lessons that I learned along the way. One of the most important is: we should pay careful attention to possible, unintended psychological harm in clinical research. This lesson was learned early and then reinforced when I engaged CHM patients in an investigator-sponsored Phase IB clinical trial of ocular gene therapy for choroideremia. My second lesson came from the trial itself in that preliminary data may not be sufficient to predict the risks to patients in a clinical trial. In the significant push to begin a gene therapy trial for CHM patients, writing grants, recruiting personnel, interacting with regulatory authorities, acquiring research equipment to test outcome measures, I missed a third lesson. There is significant bias when the principal investigator of an investigator-sponsored clinical trial is also the treating physician in the trial. Ideally, those two roles should be kept separate. Finally, having completed the clinical trial, I learned that gene replacement with an AAV vector may not be the only genetic therapy for CHM; an antisense oligonucleotide therapy may be possible in select cases. [ABSTRACT FROM AUTHOR]

Retinitis pigmentosa 1–like 1 (RP1L1) is a component of the photoreceptor cilium. Pathogenic variants in RP1L1 lead to photoreceptor disease, suggesting an important role for RP1L1 in photoreceptor biology, though its exact function is unknown. To date, RP1L1 variants have been associated with occult macular dystrophy (a cone degeneration) and retinitis pigmentosa (a rod disease). Here, we summarize reported RP1L1 -associated photoreceptor conditions and disease-causing RP1L1 variants. We also discuss novel associations between RP1L1 and additional photoreceptor conditions—besides occult macular dystrophy and retinitis pigmentosa—and fit RP1L1 into the broader scope of photoreceptor disease. RP1L1 appears to have a complex relationship with other photoreceptor proteins and may modify disease phenotype. Ultimately, further exploration of the relationship between RP1L1 , other cilium components, and their impact on photoreceptor health is needed. [ABSTRACT FROM AUTHOR]

Pseudoxanthoma elasticum (PXE) is an autosomal recessive condition caused by mutations in the ABCC6 gene. Ocular features include angioid streaks, peau d'orange fundus, and drusen. We report a novel ABCC6 mutation causing PXE in a patient with a mixed phenotype of PXE and retinitis pigmentosa (RP). A 37-year-old female presented with decreased peripheral vision and nyctalopia. Ocular imaging revealed angioid streaks emanating from the optic nerve as well as peripheral pigmentary changes and bone spicules. Genetic testing revealed two mutations in ABCC6 in trans. No other mutation was identified. We present a rare case with ocular findings of PXE and RP in a patient with a novel ABCC6 mutation. The patient presented both with peripheral pigmentary changes and angioid streaks. Further investigation into this novel mutation would be beneficial to determine if the mutation is involved in the RP phenotype. [ABSTRACT FROM AUTHOR]

Purpose: To test the effect of docosahexanoic acid (DHA) dietary supplementation on macular function in patients with Stargardt disease. Materials and Methods: A single center, double-masked, randomized placebo-controlled trial of 11 subjects (2 males, 9 females) with Stargardt disease in a crossover design (NCT00060749). Six participants were randomized to two sequences of three month periods of DHA supplementation (2000 mg/day) followed by three months of placebo. Five participants were randomized to the opposite sequence. All participants were evaluated with a food frequency and NEI-VF25 questionnaires, complete ophthalmic examination, multifocal electroretinography (ERG, primary outcome), 30-Hz flicker ERG, Humphrey 10-2 visual field, D15 color tests and serum lipid analysis. Results: During periods of DHA supplementation, serum rose and then fell with transition to periods of placebo. None of the participants experienced greater than 20% change from baseline values of the mfERG during periods of DHA supplementation or placebo, while the average change in peak amplitude and phase angle of the flicker ERG remained similar at all visits. No significant change was observed for any of the secondary outcome measures. Eight adverse events occurred but these were not considered to be due to the treatment. Conclusions: No perceived effect of DHA supplementation on macular function was observed in a small sample of Stargardt patients who were compliant with the protocol as estimated by changes in serum DHA. This study will help design future studies of the effect of DHA supplementation on retinal function in cohorts with retinal dystrophies. [ABSTRACT FROM AUTHOR]

Introduction: Usher syndrome is a genetically heterogeneous condition and represents the most common cause of inherited combined vision and hearing loss. Deficits manifest as sensorineural hearing loss that typically develops at a young age and retinitis pigmentosa that can lead to peripheral vision loss and night blindness. As a result, this syndrome can have a significant impact on a patient's quality of life. Previous studies have described an association between Usher syndrome and Fuchs' heterochromic iridocyclitis, a form of non-granulomatous uveitis that generally presents in a unilateral manner. We present a rare finding of bilateral uveitis and, to the best of our knowledge, the first report of granulomatous uveitis as a feature in a patient with Usher syndrome. Case presentation: A 45-year-old Caucasian woman with a known history of retinitis pigmentosa presented to our clinic with suspected Usher syndrome, given her report of long-standing hearing loss. Aside from a mild loss in visual acuity, our patient was otherwise asymptomatic. Visual field testing, audiology and electroretinography findings supported the diagnosis of Usher syndrome. With slit lamp examination she was found to have bilateral keratic precipitates, with large, greasy-white, mutton-fat keratic precipitates on the endothelial surface of her left eye. A thorough work-up that included blood tests and imaging was negative for an alternative cause of her uveitis. Conclusion: We present a rare finding of bilateral uveitis and what we believe to be the first reported instance of mutton-fat keratic precipitates and granulomatous uveitis as a feature in a patient with Usher syndrome. By identifying atypical presentations of the disease, we hope to contribute to the range of ophthalmic conditions that may be seen in association with Usher syndrome. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the possibility of duplications or deletions within the CHM gene as a cause of choroideremia (CHM). Materials and Methods: Eight males and one female subject were identified in whom clinical features were consistent with a clinical diagnosis of CHM. In all cases, sequencing of the coding region and adjacent intronic splice sites did not identify a mutation. In some cases, supplemental immunoblot analysis of protein from peripheral blood leukocytes with anti-REP-1 antibody confirmed absence of Rab escort protein-1, REP-1. A multiplex ligation-dependent probe amplification assay (MLPA) for the CHM gene was developed to test for deletions and duplications within the CHM gene. Results: A duplication of exons 3-8 of the CHM gene (NM_000390.2) was identified in one case. Discussion: While likely an uncommon event, duplication within the CHM gene could be considered as an explanation for CHM cases in which no mutation is found by sequence analysis. [ABSTRACT FROM AUTHOR]

Purpose: To describe the phenotype and genotype of patients with autosomal recessive bestrophinopathy. Methodology: The phenotype of the subjects was described after a complete ophthalmological examination, and in various cases, ancillary testing of the visual field, optical coherent tomography, full field electroretinography and electrophysiology. Genetic analysis was carried out by screening the Bestrophin-1 ( BEST1) gene for mutations by dideoxy sequencing and segregation analysis. Results: We identified three previously described mutations (Ala195Val, Leu191Pro and Arg141His) and two potentially pathogenic changes (Trp93Pro and Trp287Ter) in the Best-1 gene. Two patients carried compound heterozygous mutations, Trp93Pro/Ala195Val, and Leu191Pro/Trp287Ter. Two sisters were homozygous for an Arg141His mutation. All individuals with Best1 gene mutations had signs of maculopathy. Conclusions: Our observations expand the limited number of phenotypes associated with mutations in the Best1 gene. Patients with compound heteroyzygous Best1 mutations developed atypical forms of Best disease. Two siblings with homozygous Arg141His mutation developed symptoms of typical Best vitelliform dystrophy while their parents had clinical features of mild maculopathy. [ABSTRACT FROM AUTHOR]

Abstract: Histopathology of young individuals affected by choroideremia is rarely available to allow correlation with the clinical presentation. A 30-year-old man with choroideremia died in a motor vehicle accident and one eye was subjected to histopathological examination. Immunoblot analysis of protein derived from white blood cells of a living brother, also affected with choroideremia, confirmed the absence of Rab escort protein-1, the normal CHM gene product. Direct sequencing of the coding region and adjacent splice sites of the CHM gene was undertaken on genomic DNA from the living brother and revealed a transition mutation, C to T, in exon 6 (R253X) which resulted in a stop codon and was predicted to truncate the protein product. Histopathological examination of the eye of the deceased brother showed relative independent degeneration of choriocapillaris, retinal pigment epithelium, and retina, similar to observations in the mouse model of choroideremia. In addition, mild T-lymphocytic infiltration was found within the choroid. The ophthalmic features and the pathology of choroideremia are discussed in light of new findings in the current case. [Copyright &y& Elsevier]

Purpose: To review the current literature on the detection and measurement of antiretinal antibodies.Design: Collaborative essay.Methods: Literature review and interpretation.Results: There is strong evidence to suggest a role for antiretinal antibodies, particularly those targeting recoverin and alpha-enolase, in the pathogenesis of autoimmune retinopathy (AIR). Additionally, numerous other autoantibodies have been described as putative mediators of retinal degeneration and more remain to be discovered. However, assay methods described in the literature by many laboratories for the detection of circulating antiretinal antibodies have been varied and diverse, making it difficult to interpret and compare their results.Conclusions: There is currently little standardization of laboratory methods used to detect and monitor antiretinal antibodies. To measure and monitor levels of circulating antiretinal antibodies optimally in patients with AIR, development of standardized assays with stringent internal controls is required. A multicenter collaborative and validation effort is encouraged to reach a consensus on this issue. [ABSTRACT FROM AUTHOR]

Over the past decade, there has been an exponential increase in our knowledge of heritable eye conditions. Coincidentally, our ability to provide accurate genetic diagnoses has allowed appropriate counseling to patients and families. A summary of our current understanding of ocular genetics will prove useful to clinicians, researchers, and students as an introduction to the subject. [Copyright &y& Elsevier]

Exotropia in a patient with CPEO was managed with bilateral medial rectus resections. Molecular genetic analysis of DNA from a skeletal muscle biopsy confirmed a deletion of the mitochondrial DNA. The resected muscle tendon was subjected to transmission electron microscopy, revealing muscle fibre variability and ragged red fibres with mitochondrial abnormalities. [ABSTRACT FROM AUTHOR]

Alterations to cilia are responsible for a wide range of severe disease; however, understanding of the transcriptional control of ciliogenesis remains incomplete. In this study we investigated whether altered cilia-mediated signaling contributes to the pleiotropic phenotypes caused by the Forkhead transcription factor FOXC1. Here, we show that patients with FOXC1-attributable Axenfeld–Rieger Syndrome (ARS) have a prevalence of ciliopathy-associated phenotypes comparable to syndromic ciliopathies. We demonstrate that altering the level of Foxc1 protein, via shRNA mediated inhibition, CRISPR/Cas9 mutagenesis and overexpression, modifies cilia length in vitro. These structural changes were associated with substantially perturbed cilia-dependent signaling [Hedgehog (Hh) and PDGFRα], and altered ciliary compartmentalization of the Hh pathway transcription factor, Gli2. Consistent with these data, in primary cultures of murine embryonic meninges, cilia length was significantly reduced in heterozygous and homozygous Foxc1 mutants compared to controls. Meningeal expression of the core Hh signaling components Gli1, Gli3 and Sufu was dysregulated, with comparable dysregulation of Pdgfrα signaling evident from significantly altered Pdgfrα and phosphorylated Pdgfrα expression. On the basis of these clinical and experimental findings, we propose a model that altered cilia-mediated signaling contributes to some FOXC1-induced phenotypes. [ABSTRACT FROM AUTHOR]

Zebrafish are an instrumental system for the generation of photoreceptor degeneration models, which can be utilized to determine underlying causes of photoreceptor dysfunction and death, and for the analysis of potential therapeutic compounds, as well as the characterization of regenerative responses. We review the wealth of information from existing zebrafish models of photoreceptor disease, specifically as they relate to currently accepted taxonomic classes of human rod and cone disease. We also highlight that rich, detailed information can be derived from studying photoreceptor development, structure, and function, including behavioural assessments and in vivo imaging of zebrafish. Zebrafish models are available for a diversity of photoreceptor diseases, including cone dystrophies, which are challenging to recapitulate in nocturnal mammalian systems. Newly discovered models of photoreceptor disease and drusenoid deposit formation may not only provide important insights into pathogenesis of disease, but also potential therapeutic approaches. Zebrafish have already shown their use in providing pre-clinical data prior to testing genetic therapies in clinical trials, such as antisense oligonucleotide therapy for Usher syndrome. [ABSTRACT FROM AUTHOR]

Purpose: To report a case of initial cone dystrophy that advanced to a cone-rod dystrophy with homozygous variants in the POC1B gene. Methods: Retinal structure and visual function assessments were performed using fundoscopy, spectral-domain optical coherence tomography, full field electroretinography, semi-kinetic perimetry, and Ishihara plate testing. A DNA sample was collected and sent for diagnostic molecular genetic testing with a cone-rod dystrophy panel. Results: Clinical examination and electroretinography confirmed a clinical diagnosis of cone dystrophy. Molecular genetic testing revealed homozygous variants in POC1B (c.1355 G > A, p.(Arg452Gln)). Follow-up three years later showed progression to a cone-rod dystrophy. Conclusion: Our case describes an ophthalmological phenotype associated with a homozygous POC1B missense variant and provides clinical support for variant classification. [ABSTRACT FROM AUTHOR]

Stargardt-like macular dystrophy (STGD3) represents an early onset, autosomal dominant form of macular degeneration. (e) Pentacam corneal topography of both eyes at the initial visit revealed normal corneal thickness in the left eye and mild thinning temporally in the right eye. In order to verify the hypothesis of an association of STGD3 disease with dry eyes, future evaluation of the tear film stability of STGD3 patients, especially in older patients may be instructive. [Extracted from the article]

Presents a letter to the editor about age-related macular degeneration.

Introduction: Usher syndrome is a genetically heterogeneous condition and represents the most common cause of inherited combined vision and hearing loss. Deficits manifest as sensorineural hearing loss that typically develops at a young age and retinitis pigmentosa that can lead to peripheral vision loss and night blindness. As a result, this syndrome can have a significant impact on a patient's quality of life. Previous studies have described an association between Usher syndrome and Fuchs' heterochromic iridocyclitis, a form of non-granulomatous uveitis that generally presents in a unilateral manner. We present a rare finding of bilateral uveitis and, to the best of our knowledge, the first report of granulomatous uveitis as a feature in a patient with Usher syndrome.Case Presentation: A 45-year-old Caucasian woman with a known history of retinitis pigmentosa presented to our clinic with suspected Usher syndrome, given her report of long-standing hearing loss. Aside from a mild loss in visual acuity, our patient was otherwise asymptomatic. Visual field testing, audiology and electroretinography findings supported the diagnosis of Usher syndrome. With slit lamp examination she was found to have bilateral keratic precipitates, with large, greasy-white, mutton-fat keratic precipitates on the endothelial surface of her left eye. A thorough work-up that included blood tests and imaging was negative for an alternative cause of her uveitis.Conclusion: We present a rare finding of bilateral uveitis and what we believe to be the first reported instance of mutton-fat keratic precipitates and granulomatous uveitis as a feature in a patient with Usher syndrome. By identifying atypical presentations of the disease, we hope to contribute to the range of ophthalmic conditions that may be seen in association with Usher syndrome. [ABSTRACT FROM AUTHOR]

Introduction. Choroideremia is an X-linked progressive chorioretinal degenerative disease that affects 1 in 50,000 males. Clinically, patients with choroideremia present with nightblindness and progressive loss of peripheral vision; however, typically central vision and colour vision is maintained. Choroideremia arises from a dysfunctional Rab escort protein-1 (REP-1) which is encoded by the CHM gene. The absence of REP-1 in the eye, results in the gradual degeneration of the retina, retinal pigment epithelium, and choroid causing the ocular manifestations common in affected individuals. The exact pathogenesis, however, has yet to be determined. Through genetic studies, we have determined that choroideremia can arise from deletions in the CHM gene but deletions alone do not account for all cases of choroideremia. Our study delves into the biochemical genetics of the CHM gene to determine whether other genetic mutations such as copy number variants play a role in choroideremia pathogenesis. Methods. We designed a multiplex ligation-dependent probe amplification (MLPA) assay kit for the detection of copy number variants in the CHM gene. Using our MLPA assay kit, we tested the DNA of several choroideremia patients that screened negative for genetic deletions in their CHM gene. Results. A duplication of several consecutive exons of the CHM gene was determined in one particular patient DNA sample. Discussion. Prior to this study, only deletions in the CHM gene have been linked to choroideremia pathology. The duplication in the CHM gene observed in this study represents a novel pathological mutation and potentially a novel mechanism of pathogenesis. We hope that this discovery will help us further understand the pathogenesis of choroideremia. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Reestablishing the researchers-patient compact," by I. S. Kohane and colleagues in the May 11, 2007 issue.

Photoreceptor dysfunctions and degenerative diseases are significant causes of vision loss in patients, with few effective treatments available. Targeted interventions to prevent or reverse photoreceptor-related vision loss are not possible without a thorough understanding of the underlying mechanism leading to disease, which is exceedingly difficult to accomplish in the human system. Cone diseases are particularly challenging to model, as some popular genetically modifiable model animals are nocturnal with a rod-dominant visual system and cones that have dissimilarities to human cones. As a result, cone diseases, which affect visual acuity, colour perception, and central vision in patients, are generally poorly understood in terms of pathology and mechanism. Zebrafish (Danio rerio) provide the opportunity to model photoreceptor diseases in a diurnal vertebrate with a cone-rich retina which develops many macular degeneration-like pathologies. Zebrafish undergo external development, allowing early-onset retinal diseases to be detected and studied, and many ophthalmic tools are available for zebrafish visual assessment during development and adulthood. There are numerous zebrafish models of photoreceptor disease, spanning the various types of photoreceptor disease (developmental, rod, cone, and mixed photoreceptor diseases) and genetic/molecular cause. In this review, we explore the features of zebrafish that make them uniquely poised to model cone diseases, summarize the established zebrafish models of inherited photoreceptor disease, and discuss how disease in these models compares to the human presentation, where applicable. Further, we highlight the contributions of these zebrafish models to our understanding of photoreceptor biology and disease, and discuss future directions for utilising and investigating these diverse models. [ABSTRACT FROM AUTHOR]

Background Choroideremia ( CHM) is an X-linked degeneration of the retinal pigment epithelium, photoreceptors, and choroid, which causes nyctalopia and progressive constriction of visual fields leading to blindness. The CHM gene encodes Rab escort protein 1 ( REP-1). In this work, we reviewed the phenotypes and genotypes of affected males with the purpose of understanding the functional effects of CHM mutations and their relationship with the phenotypes. Methods A retrospective review of 128 affected males was performed analyzing the onset of symptoms, visual acuity, and visual fields with respect to their mutations in the CHM gene. Results In rank order, reflecting data from this report, the most common mutations found in the CHM gene were nonsense mutations (41%), exon deletions (37%), and splice sites (14%) associated with a loss of functional protein. In the pool of 106 CHM mutations, we discovered four novel missense mutations (c.238C>T; p.L80F, c.819G>T; p.Q273H, c.1327A>G; p.M443V, and c.1370C>T; p.L457P) predicted to be severe changes affecting protein stability and folding with the effect similar to that of other types of mutations. No significant genotype-phenotype correlation was found with respect to the onset of nyctalopia, the onset of other visual symptoms, visual acuity, or width of visual fields. Conclusion There is no evidence to support exclusion of CHM patients from clinical trials based on their genotypes or any potential genotype-phenotype correlations. [ABSTRACT FROM AUTHOR]

Purpose: To identify challenges and pose solutions for communications about ocular gene therapy between patients and clinicians as clinical research progresses. Design: Literature review with recommendations. Methods: Literature review of science communication best practices to inform recommendations for patient-clinician discussions about ocular gene therapy. Results: Clinicians need to employ communications about ocular gene therapy that are both attentive to patient priorities and concerns and responsive to other sources of information, including overly positive news media and the Internet. Coverage often conflates research with therapy--clinical trials are experimental and are not risk free. If proven safe and efficacious, gene therapy may present a treatment but not a cure for patients who have already experienced vision loss. Clinicians can assist patients by providing realistic estimates for lengthy clinical development timelines and positioning current research within models of clinical translation. This enables patients to weigh future therapeutic options when making current disease management decisions. Conclusions: Ocular gene therapy clinical trials are raising hopes for treating a myriad of hereditary retinopathies, but most such therapies are many years in the future. Clinicians should be prepared to counter overly positive messaging, found in news media and on the Internet, with optimism tempered by evidence to support the ethical translation of gene therapy and other novel biotherapeutics. [ABSTRACT FROM AUTHOR]

Dilated cardiomyopathy with ataxia syndrome (DCMA) is a rare mitochondrial condition associated with early onset cardiomyopathy and non-progressive ataxia. The cardiac manifestations may be progressive and often severe, resulting in significant morbidity and mortality. While optic nerve atrophy has been described in patients with DCMA, to our knowledge, there have been no reports of additional ocular phenotypes. We present two related Dariusleut Hutterite patients with documented DCMA syndrome and disorders of ocular motility: poor smooth pursuit and difficulty initiating saccadic eye movements and maintaining target fixation. We thus report the first cases of oculomotor apraxia in DCMA syndrome. By identifying these associated findings early in life, we hope to improve both the clinical diagnostic accuracy and timeliness of intervention in cases of DCMA. [ABSTRACT FROM PUBLISHER]

PURPOSE: To review what progress has been made towards the application of ocular gene therapy to prevent progressive vision loss in patients affected by choroideremia. DESIGN: A Perspective based on the collective opinions of researchers and clinicians actively engaged in vision research on choroideremia and a review of current literature. METHODS: Researchers from Europe, Canada, Australia, and the United States were convened to the first International Choroideremia Research Symposium held in Sommie`res, France in September 2011. Attendees shared their collective understanding of the pathophysiology of choroideremia and current trends in the development of treatments, with an emphasis on the potential of gene therapy as an achievable approach. Supplemental perspectives are provided along with an update of progress made since the meeting. RESULTS: The complexity of treating a retinal disease such as choroideremia that affects multiple tissue layers has been brought to light. The genetic basis of choroideremia must be thoroughly deciphered and appropriate clinical tests selected to follow disease progression and evaluate the efficiency of treatments. CONCLUSIONS: Whereas the time frame for the development of therapies for some retinal dystrophies may be in the years hence, gene therapy trials for choroideremia have started in the United Kingdom and results are pending. These first trials may help resolve the remaining issues associated with the treatment of this disease. [ABSTRACT FROM AUTHOR]

Marked progress has been made over the past 15 years in defining the specific biochemical defects and underlying molecular mechanisms of oxidative phosphorylation disorders, but limited information is currently available on the development and evaluation of effective treatment approaches. Metabolic therapies that have been reported to produce a positive effect include coenzyme Q10 (ubiquinone), other antioxidants such as ascorbic acid and vitamin E, riboflavin, thiamine, niacin, vitamin K (phylloquinone and menadione), and carnitine. The goal of these therapies is to increase mitochondrial ATP production, and to slow or arrest the progression of clinical symptoms. In the present study, we demonstrate for the first time that there is a significant increase in ATP synthetic capacity in lymphocytes from patients undergoing cofactor treatment. We also examined in vitro cofactor supplementation in control lymphocytes in order to determine the effect of the individual components of the cofactor treatment on ATP synthesis. A dose-dependent increase in ATP synthesis with CoQ10 incubation was demonstrated, which supports the proposal that CoQ10 may have a beneficial effect in the treatment of oxidative phosphorylation (OXPHOS) disorders. [Copyright &y& Elsevier]

A 28-year old woman had an ocular syndrome consisting of congenital lid and punctal anomalies, and corneal and chorioretinal dystrophy without facial dysmorphism. These combined malformations of the ocular adnexae and both anterior and posterior ocular segments have not been previously described and appear to represent a novel syndrome. Direct sequencing of PAX6 and the DNA-binding domain of FOXC1 failed to detect a mutation. [ABSTRACT FROM AUTHOR]

Biochemical analysis of oxidative phosphorylation (OXPHOS) disorders is traditionally carried out on muscle biopsies, cultured fibroblasts, and transformed lymphocytes. Here we present a new screening technique using lymphocytes to identify OXPHOS dysfunction and initially avoid an invasive diagnostic procedure. Lymphocytes represent an easily obtainable source of tissue that presents advantages over the use of fibroblasts or lymphoblast cell lines. The time delay in culturing skin fibroblasts and the interactions between cell transformation and mitochondrial activity are avoided in this methodology. The method requires a small amount of blood (<5 mL); can be completed in a few hours, and allows for repeated measurements. Our assay has been adapted from published methods utilizing cultured fibroblasts and transformed lymphocytes, and our data suggest that measurement of ATP synthesis in lymphocytes is an effective screening tool for diagnosing OXPHOS disorders. This method may also provide an objective tool for monitoring response to treatment and evaluating progression of disease. [Copyright &y& Elsevier]

Background: Canavan disease is an autosomal recessive, neurodegenerative disorder caused by mutations in ASPA, a gene encoding the enzyme aspartoacylase. Patients present with macrocephaly, developmental delay, hypotonia, vision impairment and accumulation of N-acetylaspartic acid. Progressive white matter changes occur in the central nervous system. The disorder is often fatal in early childhood, but milder forms exist. Materials and methods: Case report. Results: We present the case of a 31-year-old male with mild/juvenile Canavan disease who had severe vision loss due to a retinal degeneration resembling retinitis pigmentosa. Prior to this case, vision loss in Canavan disease had been attributed to optic atrophy based on fundoscopic evidence of optic nerve pallor. Investigations for an alternative cause for our patient's retinal degeneration were non-revealing. Conclusion: We wonder if retinal degeneration may not have been previously recognized as a feature of Canavan disease. We highlight findings from animal models of Canavan disease to further support the association between Canavan disease and retinal degeneration. [ABSTRACT FROM AUTHOR]

An 11-month-old infant girl presented with right-sided features of aplasia cutis congenita of the scalp, unilateral epibulbar dermoids, eccentric pupil, coloboma of the right upper eyelid, and depigmentation of the fundus surrounding the right optic nerve. These findings were similar to the oculoectodermal syndrome reported by other clinicians and researchers. [ABSTRACT FROM AUTHOR]

Purpose: To describe outcomes of combined rituximab and bortezomib treatment for non-paraneoplastic autoimmune retinopathy.Case: A 37-year-old female developed photopsias and reduced vision. Electroretinography, optical coherence tomography, and positive serum anti-retinal antibodies were consistent with autoimmune retinopathy. A negative malignancy work-up specified her non-paraneoplastic presentation. Given absence of response to periocular steroids, azathioprine, and methotrexate, a combination of rituximab and bortezomib was initiated as fifth-line therapy.Results: There was no significant improvement in the patient's symptoms or visual function following treatment. The full field electroretinogram amplitudes were reduced with progressive outer retinal degeneration evident on optical coherence tomography. Post-treatment anti-retinal antibody testing demonstrated the persistence of antibodies and revealed additional antibodies not previously detected.Conclusion: Combined rituximab and bortezomib treatment did not result in significant clinical improvement and there was evidence of disease progression. Further prospective studies are required to assess the efficacy of immunotherapy in patients with autoimmune retinopathy. [ABSTRACT FROM AUTHOR]

Choroideremia is an X-linked retinal disease characterized by progressive atrophy of the choroid and retinal pigment epithelium caused by mutations in the CHM gene. SVA (SINE-R/VNTR/Alu) elements are a type of non-autonomous retrotransposon that occasionally self-replicate, reinsert randomly into a gene, and cause disease. Intragenic SVA insertions have been reported as the mechanism underlying a number of diseases including a syndromic form of retinal dystrophy, but have never been found in CHM. Here we identified and characterized a novel hemizygous SVA insertion, c.97_98inSVA (p.Arg33insSVA), in exon 2 of CHM in a male choroideremia patient. The SVA insertion's impact was evaluated by establishing a patient-derived lymphoblastoid cell line as a source of RNA for mRNA analysis of the CHM transcript, and protein for immunoblot analysis of Rab Escort Protein 1 (REP-1). Immunoblot analysis revealed the absence of REP-1 protein, while a smaller than expected PCR product was amplified from cDNA. Sequencing of this PCR product showed skipping of exon 2, denoted r.50_116del. Ophthalmic examination including psychophysical tests, visual electrophysiology, and fundus imaging showed the patient's phenotype was consistent with severe early manifestations of choroideremia. This case is the first report of a SVA insertion in the CHM gene causing choroideremia. [ABSTRACT FROM AUTHOR]

Purpose: To discuss progress in research on choroideremia (CHM) and related retinopathies with special emphasis on gene therapy approaches. Methods: Biomedical and clinical researchers from across the world as well as representatives of the social science research community were convened to the 2nd International Scientific Symposium for Choroideremia in Denver, Colorado in June 2014 to enhance our understanding of CHM and accelerate the translation of research to clinical application for the benefit of those affected by CHM. Results: Pre-clinical research using cell and animal models continues to further our understanding in the pathogenesis of CHM as well as to demonstrate proof-of-concept for gene transfer strategies. With the advent of modern imaging technology, better outcome measures are being defined for upcoming clinical trials. Results from the first gene therapy trial in CHM show promise, w ith sustained visual improvement over 6 months post-treatment. Current and next-generation gene transfer approaches may make targeted vector delivery possible in the future for CHM and other inherited retinal diseases. Conclusions: While no accepted therapies exist for CHM, promising approaches using viral-vectored gene therapy and cell therapies are entering clinical trials for eye diseases, with gene therapy trials underway for CHM. [ABSTRACT FROM AUTHOR]

Purpose To examine the prevalence of systemic and ocular disease among choroideremia patients and carriers. Methods A cross-sectional analysis was performed on responses from affected males with choroideremia, female carriers, and unaffected brothers to an Internet-based survey made available from September 2009 to November 2010. Affected males were classified into two groups, those with or without functional vision. Carrier females were classified into those with and without symptoms. Comparisons were made between these groups. Results There was a higher prevalence of dry eye in our respondents than the North American population. The prevalence of dry eye, cataract, hypertension, diabetes, psychological problems and hypercholesterolemia were higher in choroideremia males without functional vision compared to those with functional vision. Likewise, statin intake was more prevalent among the affected males without functional vision than those with functional vision. After age adjustment, any differences between the two subgroups of male patients (with and without functional vision) were not significant. Conclusion Age plays an important role in determining the onset of severe visual impairment with loss of functional vision in male subjects affected by choroideremia. Although Internet surveys have limitations such as the use of self-reported diagnoses and the possibility that the responses may not be representative of the population as a whole, this study shows that such surveys can provide data quickly and easily, and for rare diseases such as choroideremia, with relatively large numbers of responses. [ABSTRACT FROM AUTHOR]

Congenital stationary night blindness (CSNB) is a nonprogressive retinal disorder that can be associated with impaired night vision. The last decade has witnessed huge progress in ophthalmic genetics, including the identification of three genes implicated in the pathogenicity of autosomal-recessive CSNB. However, not all patients studied could be associated with mutations in these genes and thus other genes certainly underlie this disorder. Here, we report a large multigeneration family with five affected individuals manifesting symptoms of night blindness. A genome-wide scan localized the disease interval to chromosome 15q, and recombination events in affected individuals refined the critical interval to a 10.41 cM (6.53 Mb) region that harbors SLC24A1, a member of the solute carrier protein superfamily. Sequencing of all the coding exons identified a 2 bp deletion in exon 2: c.1613_1614del, which is predicted to result in a frame shift that leads to premature termination of SLC24A1 (p.F538CfsX23) and segregates with the disorder under an autosomal-recessive model. Expression analysis using mouse ocular tissues shows that Slc24a1 is expressed in the retina around postnatal day 7. In situ and immunohistological studies localized both SLC24A1 and Slc24a1 to the inner segment, outer and inner nuclear layers, and ganglion cells of the retina, respectively. Our data expand the genetic basis of CSNB and highlight the indispensible function of SLC24A1 in retinal function and/or maintenance in humans. [ABSTRACT FROM AUTHOR]

Background: Choroideremia (CHM) is a progressive X-linked retinopathy caused by mutations in the CHM gene, which encodes Rab escort protein-1 (REP-1), an escort protein involved in the prenylation of Rabs. Under-prenylation of certain Rabs, as a result of loss of function mutations in REP-1, could affect vesicular trafficking, exocytosis and secretion in peripheral cells of CHM patients. Methodology/Principal Findings: To evaluate this hypothesis, intracellular vesicle transport, lysosomal acidification and rates of proteolytic degradation were studied in monocytes (CD14+ fraction) and primary skin fibroblasts from the nine agematched controls and thirteen CHM patients carrying 10 different loss-of-function mutations. With the use of pHrodo™ BioParticles® conjugated with E. coli, collagen I coated FluoSpheres beads and fluorescent DQ™ ovalbumin with BODYPY FL dye, we demonstrated for the first time that lysosomal pH was increased inmonocytes of CHM patients and, as a consequence, the rates of proteolytic degradation were slowed. Microarray analysis of gene expression revealed that some genes involved in the immune response, small GTPase regulation, transcription, cell adhesion and the regulation of exocytosis were significantly up and down regulated in cells from CHM patients compared to controls. Finally, CHM fibroblasts secreted significantly lower levels of cytokine/growth factors such as macrophage chemoattractant protein-1 (MCP-1), pigment epithelial derived factor (PEDF), tumor necrosis factor (TNF) alpha, fibroblast growth factor (FGF) beta and interleukin (lL)-8. Conclusions/Significance: We demonstrated for the first time that peripheral cells of CHM patients had increased pH levels in lysosomes, reduced rates of proteolytic degradation and altered secretion of cytokines. Peripheral cells from CHM patients expose characteristics that were not previously recognized and could used as an alternative models to study the effects of different mutations in the REP-1 gene on mechanism of CHM development in human population. [ABSTRACT FROM AUTHOR]

Background: Thirty-nine patients have been described with deletions involving chromosome 6p25. However, relatively few of these deletions have had molecular characterization. Common phenotypes of 6p25 deletion syndrome patients include hydrocephalus, hearing loss, and ocular, craniofacial, skeletal, cardiac, and renal malformations. Molecular characterization of deletions can identify genes that are responsible for these phenotypes. Methods: We report the clinical phenotype of seven patients with terminal deletions of chromosome 6p25 and compare them to previously reported patients. Molecular characterization of the deletions was performed using polymorphic marker analysis to determine the extents of the deletions in these seven 6p25 deletion syndrome patients. Results: Our results, and previous data, show that ocular dysgenesis and hearing impairment are the two most highly penetrant phenotypes of the 6p25 deletion syndrome. While deletion of the forkhead box C1 gene (FOXC1) probably underlies the ocular dysgenesis, no gene in this region is known to be involved in hearing impairment. Conclusions: Ocular dysgenesis and hearing impairment are the two most common phenotypes of 6p25 deletion syndrome. We conclude that a locus for dominant hearing loss is present at 6p25 and that this locus is restricted to a region distal to D6S1617. Molecular characterization of more 6p25 deletion patients will aid in refinement of this locus and the identification of a gene involved in dominant hearing loss. [ABSTRACT FROM AUTHOR]

: PurposeTo reexamine a large Albertan family previously reported with a progressive cone dystrophy with variable phenotype and to map the disorder using molecular genetic techniques.: DesignObservational case series.: ParticipantsTwenty-nine subjects (10 affected) from four generations of a large kindred were clinically examined. Twenty-three of these individuals, as well as two unaffected spouses, were included in the molecular genetic study. Subject ages ranged from 17 to 91 years of age.: MethodsDisease status and associated ocular abnormalities were assessed primarily by measurement of visual acuity, color vision, fundus photography, and both full-field and multifocal electroretinography (ERG and mfERG). Linkage of the disorder to the rhodopsin gene was studied using microsatellites. A mutational screen of the CRX gene was performed to identify coding sequence changes.: Main outcome measuresVisual acuity and color discrimination were reduced in clinically affected individuals; full-field flash ERG was used to measure function of both cones and rods. mfERG and fundus photography allowed documentation of the observed macular changes.: ResultsWe noted a variable, adult-onset macular dystrophy, progressing in some cases to a retinitis pigmentosa-like phenotype. Both photopic and scotopic full-field ERG amplitudes were reduced by approximately 50%, demonstrating involvement of both photoreceptor systems. A reduced b-wave amplitude with a relatively preserved a-wave was observed at both cone and rod levels. Macular involvement was confirmed by mfERG. The rhodopsin locus was excluded by haplotype analysis. A novel frameshift mutation was detected in exon III of the CRX retinal homeobox gene. ERG and molecular genetic findings were consistent with the reclassification of this disease as an autosomal dominant cone-rod dystrophy (CRD): ConclusionsWe report a novel CRX mutation causing autosomal dominant CRD. Observed ERG changes suggest that this mutation primarily impairs inner retinal function. Because retinal expression of CRX is limited to photoreceptors, this dysfunction may be the result of faulty photoreceptor communication with second-order retinal neurons. We propose misexpression of gated cation channels caused by altered CRX activity as one putative mechanism by which a sole photoreceptor defect may selectively impair neurotransmission without disrupting the upstream events of phototransduction. [Copyright &y& Elsevier]

Choroideremia is an incurable X-linked retinal degeneration caused by mutations in the gene encoding Rab escort protein-1. A group of clinically defined and genotyped patients were studied to determine: (1) the degree of rod and cone dysfunction and structural abnormality in the central retina and the level of macular pigment; and (2) the response of macular pigment and foveal vision to a 6month trial of supplementation with oral lutein (at 20 mg per day). Rod and cone-mediated function was measured with dark-adapted static perimetry; in vivo retinal structure was determined with optical coherence tomography; and macular pigment optical density was measured with heterochromatic flicker photometry. In this cohort of patients (ages 15–65 years), both rod- and cone-mediated central function declined with age as did central retinal thickness. Macular pigment levels did not differ between patients and male control subjects. Supplementation of oral lutein in a subset of patients led to an increase in serum lutein and macular pigment levels; absolute foveal sensitivity did not change. It is concluded that macular pigment density can be augmented by oral intake of lutein in patients with choroideremia. There was no short-term change in the central vision of the patients on the supplement, but long-term influences of lutein supplementation on disease natural history warrant further study. [ABSTRACT FROM AUTHOR]

Stargardt-like macular dystrophy (STGD3, MIM 600110) and autosomal dominant macular dystrophy (adMD) are inherited forms of macular degeneration characterized by decreased visual acuity, macular atrophy and extensive fundus flecks. Genetic mapping data suggest that mutations in a single gene may be responsible for both conditions, already known to bear clinical resemblance. Here we limit the minimum genetic region for STGD3 and adMD to a 0.6-cM interval by recombination breakpoint mapping and identify a single 5-bp deletion within the protein-coding region of a new retinal photoreceptor-specific gene, ELOVL4, in all affected members of STGD3 and adMD families. Bioinformatic analysis of ELOVL4 revealed that it has homology to a group of yeast proteins that function in the biosynthesis of very long chain fatty acids. Our results are therefore the first to implicate the biosynthesis of fatty acids in the pathogenesis of inherited macular degeneration. [ABSTRACT FROM AUTHOR]

Photoreceptor disease results in irreparable vision loss and blindness, which has a dramatic impact on quality of life. Pathogenic mutations in RP1L1 lead to photoreceptor degenerations such as occult macular dystrophy and retinitis pigmentosa. RP1L1 is a component of the photoreceptor axoneme, the backbone structure of the photoreceptor's light-sensing outer segment. We generated an rp1l1 zebrafish mutant using CRISPR/Cas9 genome editing. Mutant animals had progressive photoreceptor functional defects as determined by electrophysiological assessment. Optical coherence tomography showed gaps in the photoreceptor layer, disrupted photoreceptor mosaics, and thinner retinas. Mutant retinas had disorganized photoreceptor outer segments and lipid-rich subretinal drusenoid deposits between the photoreceptors and retinal pigment epithelium. Our mutant is a novel model of RP1L1-associated photoreceptor disease and the first zebrafish model of photoreceptor degeneration with reported subretinal drusenoid deposits, a feature of age-related macular degeneration. [ABSTRACT FROM AUTHOR]

: PurposeTo investigate severe unilateral vision loss in a choroideremia carrier.: DesignCase report.: MethodsOcular examination, genetic testing, Humphrey visual fields, full-field and multifocal (mf) electroretinogram (ERG) tests were used to study a family with choroideremia.: ResultsIn a carrier with unilateral central vision loss, mfERG showed severely reduced amplitudes which correlated with a band of retinal pigment epithelial and choroidal atrophy in the macula, a dense central scotoma on Humphrey visual fields testing, and decreased ERG amplitudes.: ConclusionsMultifocal ERG may be a sensitive tool to measure functional abnormalities in choroideremia carriers. Mosaic inactivation of the normal gene may cause expression of the mutation with severe vision loss in choroideremia carriers. [Copyright &y& Elsevier]

Purpose: To analyze the variability of clinical and electrophysiological characteristics in X-linked choroideremia and provide the first report of a negative electroretinogram in choroideremia. Design: Retrospective study. Participants: The records of 18 male patients with choroideremia and 8 female carriers were evaluated. Methods: The data were reviewed regarding visual acuity (VA), color vision, perimetry, fundus autofluorescence, and full-field electroretinography (according to standards of the International Society for Clinical Electrophysiology of Vision). Main Outcome Measures: Morphological and functional phenotype characteristics, fundus autofluorescence, electroretinography, and Rab escort protein 1 (REP-1) mutations. Results: Four unrelated families with choroideremia (9 affected males, 7 carriers) and 10 unrelated individuals (9 affected males, 1 carrier) were included. Mutational analysis, performed in 2 families and 3 individual males, revealed REP-1 mutations in all except 1 male. The age of the males ranged from 5.9 to 63.0 years (mean, 33.9), and VA ranged from hand movements to 1.0 (median, 0.7). Fundus autofluorescence (n = 7) showed defects in the retinal pigment epithelium in all males. Electroretinography (n = 13) was almost undetectable in 6 males and reduced in 6, indicating a rod–cone dystrophy. A further male showed a negative electroretinogram, with a b:a wave ratio of 0.5. Visual acuity of the 8 carriers (age, 4.8–56.8 years [mean, 24.0]) ranged from light perception to 1.2 (median, 1.0). Light perception was present in 1 carrier manifesting choroideremia with distinct chorioretinal atrophy. Pigmentary stippling, seen in the other carriers, was seen in fundus autofluorescence (n = 1) with a distinct speckled pattern. Electroretinograms were normal in 6 of 7 and reduced in the manifesting carrier. Defects in color vision and visual field were found in affected males and in the female carriers. Conclusions: The phenotype of choroideremia presents with high variability. In addition to the previously reported findings, we observed a negative electroretinogram, indicating a postreceptoral retinal dysfunction, in 1 affected male; severe course of choroideremia with early blindness in 1 manifesting carrier; color vision deficits in the majority of affected males and carriers; and characteristic alterations in fundus autofluorescence. [Copyright &y& Elsevier]