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DeLuca AP, Whitmore SS, Tatro NJ, Andorf JL, Faga BP, Faga LA, Colins MM, Luse MA, Fenner BJ, Stone EM, Scheetz TE. Using Goldmann Visual Field Volume to Track Disease Progression in Choroideremia. OPHTHALMOLOGY SCIENCE 2023; 3:100397. [PMID: 38025158 PMCID: PMC10630671 DOI: 10.1016/j.xops.2023.100397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/18/2023] [Revised: 08/31/2023] [Accepted: 09/06/2023] [Indexed: 12/01/2023]
Abstract
Purpose Choroideremia is an X-linked choroidopathy caused by pathogenic variants in the CHM gene. It is characterized by the early appearance of multiple scotomas in the peripheral visual field that spread and coalesce, usually sparing central vision until late in the disease. These features make quantitative monitoring of visual decline particularly challenging. Here, we describe a novel computational approach to convert Goldmann visual field (GVF) data into quantitative volumetric measurements. With this approach, we analyzed visual field loss in a longitudinal, retrospective cohort of patients with choroideremia. Design Single-center, retrospective, cohort study. Participants We analyzed data from 238 clinic visits of 56 molecularly-confirmed male patients with choroideremia from 41 families (range, 1-27 visits per patient). Patients had a median follow up of 4 years (range, 0-56 years) with an age range of 5 to 76 years at the time of their visits. Methods Clinical data from molecularly-confirmed patients with choroideremia, including GVF data, were included for analysis. Goldmann visual field records were traced using a tablet-based application, and the 3-dimensional hill of vision was interpolated for each trace. This procedure allowed quantification of visual field loss from data collected over decades with differing protocols, including different or incomplete isopters. Visual acuity (VA) data were collected and converted to logarithm of the minimum angle of resolution values. A delayed exponential mixed-effects model was used to evaluate the loss of visual field volume over time. Main Outcome Measures Visual acuity and GVF volume. Results The estimated mean age at disease onset was 12.6 years (standard deviation, 9.1 years; 95% quantile interval, 6.5-36.4 years). The mean field volume loss was 6.8% per year (standard deviation, 4.5%; 95% quantile interval, 1.9%-18.8%) based on exponential modeling. Field volume was more strongly correlated between eyes (r2 = 0.935) than best-corrected VA (r2 = 0.285). Conclusions Volumetric analysis of GVF data enabled quantification of peripheral visual function in patients with choroideremia and evaluation of disease progression. The methods presented here may facilitate the analysis of historical GVF data from patients with inherited retinal disease and other diseases associated with visual field loss. This work informs the creation of appropriate outcome measures in choroideremia therapeutic trials, particularly in trial designs. Financial Disclosures Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
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Affiliation(s)
- Adam P. DeLuca
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - S. Scott Whitmore
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Nicole J. Tatro
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Jeaneen L. Andorf
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Ben P. Faga
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Laurel A. Faga
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Malia M. Colins
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Meagan A. Luse
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Beau J. Fenner
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
- Department of Medical Retina, Singapore National Eye Centre, Singapore
- Singapore Eye Research Institute, Singapore
- Ophthalmology and Visual Sciences Academic Clinical Programme, SingHealth Duke-NUS Academic Medical Centre, Duke-NUS Graduate Medical School, Singapore
| | - Edwin M. Stone
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
| | - Todd E. Scheetz
- The University of Iowa Institute for Vision Research & Department of Ophthalmology and Visual Sciences, Carver College of Medicine, The University of Iowa, Iowa City, Iowa
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Ang JL, Wright AF, Dhillon B, Cackett P. Choroidal neovascularisation in a predicted female choroideraemia carrier treated with intravitreal anti-vascular endothelial growth factor. Eur J Ophthalmol 2021; 31:4-10. [PMID: 33884923 DOI: 10.1177/1120672120965495] [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: 11/15/2022]
Abstract
PURPOSE To report a case of choroidal neovascularisation and leakage in a myopic female predicted to be a choroideraemia carrier treated with intravitreal anti-vascular endothelial growth factor (anti-VEGF). METHODS Case report. RESULTS A female magazine editor presented with sudden decrease in vision in her right eye, with Snellen visual acuities (VAs) of 1/60 and 3/60 in the right and left eyes respectively. She was diagnosed with choroidal neovascularisation (CNV) formation and subretinal haemorrhage in her right eye. This is on a background of previous presentations, the first of which was 20 years ago for declining left eye vision. She was subsequently found to be a predicted choroideraemia carrier. However, she also has high myopia, and it is unclear whether the predicted choroideraemia carrier status or high myopia is the main underlying cause of her CNV, although we believe that the former is more likely. The first episode of CNV in her right eye was treated successfully with intravitreal anti-VEGF. However, she experienced four further CNV reactivations in her right eye, all of which were treated successfully with anti-VEGF. At her last follow-up visit to date, Snellen VAs were 6/9 and 3/60 in her right and left eye respectively. CONCLUSION This is a unique case of CNV formation in a predicted choroideraemia carrier who also has co-existent high myopia. Prompt treatment of CNV activity with anti-VEGF has been efficacious in prevention of subretinal fibrosis and irreversible vision loss and allowed the patient to continue working in her chosen career.
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Affiliation(s)
| | - Alan F Wright
- MRC Institute of Genetics and Molecular Medicine, Edinburgh, UK
| | - Baljean Dhillon
- Princess Alexandra Eye Pavilion, Edinburgh, UK.,The University of Edinburgh, Edinburgh, UK
| | - Peter Cackett
- Princess Alexandra Eye Pavilion, Edinburgh, UK.,The University of Edinburgh, Edinburgh, UK
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Hagag AM, Mitsios A, Narayan A, Abbouda A, Webster AR, Dubis AM, Moosajee M. Prospective deep phenotyping of choroideremia patients using multimodal structure-function approaches. Eye (Lond) 2021; 35:838-852. [PMID: 32467628 PMCID: PMC8027673 DOI: 10.1038/s41433-020-0974-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2020] [Revised: 05/13/2020] [Accepted: 05/13/2020] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To investigate the retinal changes in choroideremia (CHM) patients to determine correlations between age, structure and function. SUBJECTS/METHODS Twenty-six eyes from 13 male CHM patients were included in this prospective longitudinal study. Participants were divided into <50-year (n = 8) and ≥50-year (n = 5) old groups. Patients were seen at baseline, 6-month, and 1-year visits. Optical coherence tomography (OCT), OCT angiography, and fundus autofluorescence were performed to measure central foveal (CFT) and subfoveal choroidal thickness (SCT), as well as areas of preserved choriocapillaris (CC), ellipsoid zone (EZ), and autofluorescence (PAF). Patients also underwent functional investigations including visual acuity (VA), contrast sensitivity (CS), colour testing, microperimetry, dark adaptometry, and handheld electroretinogram (ERG). Vision-related quality-of-life was assessed by using the NEI-VFQ-25 questionnaire. RESULTS Over the 1-year follow-up period, progressive loss was detected in SCT, EZ, CC, PAF, and CFT. Those ≥50-years exhibited more structural and functional defects with SCT, EZ, CC, and PAF showing strong correlation with patient age (rho ≤ -0.47, p ≤ 0.02). CS and VA did not change over the year, but CS was significantly correlated with age (rho = -0.63, p = 0.001). Delayed to unmeasurable dark adaptation, decreased colour discrimination and no detectable ERG activity were observed in all patients. Minimal functional deterioration was observed over one year with a general trend of slower progression in the ≥50-years group. CONCLUSIONS Quantitative structural parameters including SCT, CC, EZ, and PAF are most useful for disease monitoring in CHM. Extended follow-up studies are required to determine longitudinal functional changes.
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Affiliation(s)
- Ahmed M Hagag
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, London, UK
| | - Andreas Mitsios
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, London, UK
| | | | - Alessandro Abbouda
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, London, UK
| | - Andrew R Webster
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, London, UK
| | - Adam M Dubis
- Moorfields Eye Hospital NHS Foundation Trust, London, UK
- UCL Institute of Ophthalmology, London, UK
| | - Mariya Moosajee
- Moorfields Eye Hospital NHS Foundation Trust, London, UK.
- UCL Institute of Ophthalmology, London, UK.
- Department of Ophthalmology, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK.
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Jauregui R, Park KS, Tanaka AJ, Cho A, Paavo M, Zernant J, Francis JH, Allikmets R, Sparrow JR, Tsang SH. Spectrum of Disease Severity and Phenotype in Choroideremia Carriers. Am J Ophthalmol 2019; 207:77-86. [PMID: 31181178 DOI: 10.1016/j.ajo.2019.06.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 05/31/2019] [Accepted: 06/01/2019] [Indexed: 10/26/2022]
Abstract
PURPOSE To characterize and bring awareness to the disease spectrum of female choroideremia patients, as severity can vary from mild to severe disease, comparable to that observed in male patients. DESIGN Retrospective cohort study. METHODS Twelve female carriers of disease-causing variants in the CHM gene confirmed by molecular genetic sequencing were characterized clinically and imaged with short-wave fundus autofluorescence (SW-FAF), spectral-domain optical coherence tomography (OCT), and color fundus imaging. RESULTS Twelve unrelated female patients with a clinical and genetic diagnosis of choroideremia carriers were included in this study. Disease severity among these phenotypes ranged from mild to severe, resembling the typical presentation of choroideremia in male patients. Mild disease presented with retinal pigment epithelium mottling, a patchy pattern of hypoautofluorescent speckles on SW-FAF, and intact retinal layers on spectral-domain OCT. Severe disease presented with widespread chorioretinal atrophy as shown by SW-FAF and spectral-domain OCT. Each of the identified genetic variants in CHM was predicted to be disease-causing according to in silico prediction software. Disease progression analysis of 4 patients with follow-up showed a decline in visual acuity for 2 patients, with progression observed on spectral-domain OCT in 1 of the patients. No significant disease progression on SW-FAF was observed for any of the patients. CONCLUSIONS Female carriers of choroideremia can present with a wide range of clinical phenotypes and disease severity, from mild to severe disease, similar to male subjects. Symptomatic female subjects should be considered for current and upcoming gene replacement therapy clinical trials.
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Suzuki K, Gocho K, Akeo K, Kikuchi S, Kubota D, Katagiri S, Fujinami K, Tsunoda K, Iwata T, Yamaki K, Igarashi T, Nakano T, Takahashi H, Hayashi T, Kameya S. High-Resolution Retinal Imaging Reveals Preserved Cone Photoreceptor Density and Choroidal Thickness in Female Carriers of Choroideremia. Ophthalmic Surg Lasers Imaging Retina 2019; 50:76-85. [DOI: 10.3928/23258160-20190129-03] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2018] [Accepted: 11/02/2018] [Indexed: 11/20/2022]
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Ouyang P, Li Y, Zhang F, Zhu C, Zou B, Le J, Zhang L. A frameshift mutation in the CHM gene causes choroideremia with acute angle‑closure glaucoma. Mol Med Rep 2018; 17:7918-7924. [PMID: 29620233 DOI: 10.3892/mmr.2018.8851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Accepted: 03/22/2018] [Indexed: 11/06/2022] Open
Abstract
Choroideremia is an X‑linked recessive chorioretinal degenerative disease that is characterized by progressive centripetal loss of the photoreceptor, retinal pigment epithelium (RPE), and choriocapillaris layers. The CHM gene [choroideremia (Rab escort protein 1)] has been identified as the pathogenic gene in choroideremia. The aim of the present study was to describe the clinical and genetic characteristics of a family with choroideremia family. In the present study, a family with choroideremia presenting with serious chorioretinal atrophy and pigment proliferation, shallow anterior chambers, angle closure and high intraocular pressure (IOP) were recruited. The affected family members underwent a complete ophthalmologic examination. DNA samples obtained from the proband II:1 and the patient II:2 were used for targeted exome sequencing of the CHM gene. PCR amplification and Sanger sequencing were used to validate the variations exhibited in family members and controls. A novel frameshift mutation c.280delA (p.Thr94LeufsTer32), in CHM was identified in the male proband, the normal carrier I:2 and the phenotyped carrier II:2, which was absent in the normal individual II:3 as well as in 200 normal controls. Comparing the amino acid sequences of CHM between multiple species through Clustal Omega indicated conserved amino acids in these mutant sites. Additionally, an X‑chromosome inactivation (XCI) assay was performed in the female carriers in the family, in which DNA of the abnormal carrier II:2 and normal carrier I:2 showed a random XCI pattern. To conclude, the present findings strongly indicate that the c.280delA mutation is a disease‑causing mutation in our choroideremia pedigree with acute angle‑closure glaucoma.
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Affiliation(s)
- Pingbo Ouyang
- School of Information Science and Engineering, Central South University, Changsha, Hunan 410083, P.R. China
| | - Yun Li
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Feng Zhang
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Chengzhang Zhu
- School of Information Science and Engineering, Central South University, Changsha, Hunan 410083, P.R. China
| | - Beiji Zou
- School of Information Science and Engineering, Central South University, Changsha, Hunan 410083, P.R. China
| | - Jianlan Le
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Lusi Zhang
- Department of Ophthalmology, The Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
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7
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Yang L, Ijaz I, Cheng J, Wei C, Tan X, Khan MA, Fu X, Fu J. Evaluation of amplification refractory mutation system (ARMS) technique for quick and accurate prenatal gene diagnosis of CHM variant in choroideremia. APPLICATION OF CLINICAL GENETICS 2017; 11:1-8. [PMID: 29296092 PMCID: PMC5741072 DOI: 10.2147/tacg.s144383] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Choroideremia is a rare X-linked recessive inherited disorder that causes chorioretinal dystrophy leading to visual impairment in its early stages which finally causes total blindness in the affected person. It is caused due to mutations in the CHM gene. In this study, we have recruited a pedigree with choroideremia and detected a nonsense variant (c.C799T:p.R267X) in CHM of the proband (I:1). Different primer sets for amplification refractory mutation system (ARMS) were designed and PCR conditions were optimized. Then, we evaluated the sequence variant in the patient, carrier, and a fetus by using ARMS technique to identify if they inherited the pathogenic gene from parental generation; we used amniotic fluid DNA for the diagnosis of the gene in the fetus. The primer pairs, WT2+C and MT+C, amplified high specific products in different DNAs which were verified by Sanger sequencing. Based on our results, ARMS technique is fast, accurate, and reliable prenatal gene diagnostic tool to assess CHM variants. Taken together, our study indicates that ARMS technique can be used as a potential molecular tool in the diagnosis of prenatal mutation for choroideremia as well as other genetic diseases in undeveloped and developing countries, where there might be shortage of medical resources and supplies.
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Affiliation(s)
- Lisha Yang
- Key Laboratory of Epigenetics and Oncology, the Research Center for Precision Medicine, Southwest Medical University, Luzhou
| | - Iqra Ijaz
- Key Laboratory of Epigenetics and Oncology, the Research Center for Precision Medicine, Southwest Medical University, Luzhou
| | - Jingliang Cheng
- Key Laboratory of Epigenetics and Oncology, the Research Center for Precision Medicine, Southwest Medical University, Luzhou.,Department of Pathology, Hunan Normal University College of Medicine, Changsha
| | - Chunli Wei
- Key Laboratory of Epigenetics and Oncology, the Research Center for Precision Medicine, Southwest Medical University, Luzhou.,State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (SAR)
| | - Xiaojun Tan
- Reproductive and Genetic Center, the Central Hospital of Xiangtan City, Xiangtan
| | - Md Asaduzzaman Khan
- Key Laboratory of Epigenetics and Oncology, the Research Center for Precision Medicine, Southwest Medical University, Luzhou
| | - Xiaodong Fu
- Department of Obstetrics and Gynecology, First Affiliated Hospital of Southwest Medical University, Luzhou, People's Republic of China
| | - Junjiang Fu
- Key Laboratory of Epigenetics and Oncology, the Research Center for Precision Medicine, Southwest Medical University, Luzhou.,Department of Pathology, Hunan Normal University College of Medicine, Changsha.,State Key Laboratory of Quality Research in Chinese Medicine, Macau University of Science and Technology, Macau (SAR)
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Zhou Q, Yao F, Han X, Li H, Yang L, Sui R. Rep1 copy number variation is an important genetic cause of choroideremia in Chinese patients. Exp Eye Res 2017; 164:64-73. [DOI: 10.1016/j.exer.2017.07.016] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 07/08/2017] [Accepted: 07/25/2017] [Indexed: 12/29/2022]
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Battu R, Jeyabalan N, Murthy P, Reddy KS, Schouten JS, Webers CA. Genetic analysis and clinical phenotype of two Indian families with X-linked choroideremia. Indian J Ophthalmol 2017; 64:924-929. [PMID: 28112135 PMCID: PMC5322709 DOI: 10.4103/0301-4738.198866] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose: This study aims to describe the phenotype and genotype of two Indian families affected with X-linked choroideremia (CHM). Materials and Methods: In these two families, the affected individuals and unaffected family members underwent a comprehensive ophthalmic examination including an optical coherence tomography (OCT) and electroretinogram. Blood samples were collected from the families for genetic analysis. Next generation sequencing (NGS) was done using a panel of 184 genes, which covered previously associated genes with retinal dystrophies. Sequencing data were analyzed for the CHM, RPGR, and RP2 genes that have been implicated in CHM and X-linked retinitis pigmentosa (XLRP), respectively. The identified variants were confirmed by Sanger sequencing in available individuals and unrelated controls. Results: In two unrelated male patients, NGS analysis revealed a previously reported 3’-splice site change c.820-1G>C in the CHM gene in the first family and hemizygous mutation c.653G>C (p.Ser218X) in the second family. The asymptomatic family members were carriers for these mutations. Spectral domain-OCT showed loss of outer retina, preservation of the inner retina, and choroidal thinning in the affected males and retinal pigment epithelial changes in the asymptomatic carriers. The identified mutations were not present in 100 controls of Indian origin. There were no potential mutations found in XLRP-associated (RPGR and RP2) genes. Conclusion: This report describes the genotype and phenotype findings in patients with CHM from India. The identified genetic mutation leads to lack of Rab escort protein-1 (REP-1) or affects the production of a REP-1 protein that is likely to cause retinal abnormalities in patients.
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Affiliation(s)
- Rajani Battu
- Department of Vitreoretina, Narayana Nethralaya, Bengaluru, Karnataka, India
| | - Nallathambi Jeyabalan
- Department of Molecular Signaling and Gene Therapy, Grow Research Laboratory, Narayana Nethralaya Foundation, Narayana Nethralaya, Bengaluru, Karnataka, India
| | - Praveen Murthy
- Department of Vitreoretina, Vittala International Institute of Ophthalmology, Bengaluru, Karnataka, India
| | - Kavita S Reddy
- Department of Genetics, Strand Life Sciences Pvt. Limited, Bengaluru, Karnataka, India
| | - Jan Sag Schouten
- Department of Ophthalmology, Maastricht University, Maastricht, The Netherlands
| | - Caroll A Webers
- Department of Ophthalmology, Maastricht University, Maastricht, The Netherlands
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PHENOTYPING CHOROIDEREMIA AND ITS CARRIER STATE WITH MULTIMODAL IMAGING TECHNIQUES. Retin Cases Brief Rep 2017; 11 Suppl 1:S178-S181. [PMID: 27599108 DOI: 10.1097/icb.0000000000000419] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To describe findings in a patient with choroideremia (CHM) and his mother, an obligate CHM carrier. METHODS Case report. RESULTS A 25-year-old man with nyctalopia and poor peripheral vision since childhood, as well as a family history consistent with an X-linked retinal disorder was diagnosed with CHM. His asymptomatic 50-year-old mother, an obligate carrier, was also examined. Fundus examination of the affected man showed significant atrophy of the choroid and retinal pigment epithelium, whereas the carrier woman showed patchy pigmentary mottling. Imaging of the affected man showed diffuse retinal pigment epithelium atrophy on optical coherence tomography and extensive areas of decreased choriocapillaris flow on optical coherence tomography angiography. By contrast, the carrier woman showed subtle retinal pigment epithelium changes on optical coherence tomography and mild flow alterations on optical coherence tomography angiography. CONCLUSION This case demonstrates the findings seen in CHM, and while CHM carrier women are often asymptomatic, they may exhibit a mosaic pattern of pigmentary change on fundus examination. Optical coherence tomography angiography may show mild choroidal flow abnormalities. This finding serves to further characterize the extent of dysfunction in CHM and its carrier state.
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11
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Cai XB, Huang XF, Tong Y, Lu QK, Jin ZB. Novel CHM mutations identified in Chinese families with Choroideremia. Sci Rep 2016; 6:35360. [PMID: 27739455 PMCID: PMC5064415 DOI: 10.1038/srep35360] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 09/28/2016] [Indexed: 11/28/2022] Open
Abstract
Choroideremia is a bilateral and progressive X-linked inherited disease characterized by widespread chorioretinal atrophy with relative sparing of the macular region. It is caused by mutations in the ubiquitously expressed CHM gene, which lead to the absence of the Rab escort protein 1 (REP-1), resulting in prenylation deficiency. Typical fundus appearances for choroideremia were found in 3 probands from three unrelated Chinese families in our study. We firstly used the targeted exome sequencing (TES) technology to detect mutations in CHM gene. Based on an established filtering strategy of data analyses, along with confirmation by co-segregation, a previously reported mutation (c.1584_1587del TGTT, p.V529Hfs*7) was identified in one family, while two novel mutations (c.227_232delinsTGTCATTTCA, p.Q76Lfs*7; c.710dupA, p.Y237_S238delinsX) were identified in the other two families. These findings not only expands the currently limited spectrum of Chinese disease-causing variants in CHM gene, but also increases our understanding of the phenotypic and genotypic correlations of choroideremia, and may potentially lead to improved genetic counseling and specific treatment for families with choroideremia as well.
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Affiliation(s)
- Xue-Bi Cai
- The Eye Hospital of Wenzhou Medical University, The State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou 325027, China
| | - Xiu-Feng Huang
- The Eye Hospital of Wenzhou Medical University, The State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou 325027, China
| | - Yi Tong
- Fuzhou Southeastern Eye Hospital, Fuzhou, 350000, China
| | - Qin-Kang Lu
- Department of Ophthalmology, Yinzhou People's Hospital, Medical School of Ningbo University, Ningbo, 315040, China
| | - Zi-Bing Jin
- The Eye Hospital of Wenzhou Medical University, The State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health, Wenzhou 325027, China
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Jolly JK, Groppe M, Birks J, Downes SM, MacLaren RE. Functional Defects in Color Vision in Patients With Choroideremia. Am J Ophthalmol 2015; 160:822-31.e3. [PMID: 26133251 DOI: 10.1016/j.ajo.2015.06.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2015] [Revised: 06/23/2015] [Accepted: 06/23/2015] [Indexed: 12/13/2022]
Abstract
PURPOSE To characterize defects in color vision in patients with choroideremia. DESIGN Prospective cohort study. METHODS Thirty patients with choroideremia (41 eyes) and 10 age-matched male controls (19 eyes) with visual acuity of ≥6/36 attending outpatient clinics in Oxford Eye Hospital underwent color vision testing with the Farnsworth-Munsell 100 hue test, visual acuity testing, and autofluorescence imaging. To exclude changes caused by degeneration of the fovea, a subgroup of 14 patients with a visual acuity ≥6/6 was analyzed. Calculated color vision total error scores were compared between the groups and related to a range of factors using a random-effects model. RESULTS Mean color vision total error scores were 120 (95% confidence interval [CI] 92, 156) in the ≥6/6 choroideremia group, 206 (95% CI 161, 266) in the <6/6 visual acuity choroideremia group, and 47 (95% CI 32, 69) in the control group. Covariate analysis showed a significant difference in color vision total error score between the groups (P < .001 between each group). CONCLUSIONS Patients with choroideremia have a functional defect in color vision compared with age-matched controls. The color vision defect deteriorates as the degeneration encroaches on the fovea. The presence of an early functional defect in color vision provides a useful biomarker against which to assess successful gene transfer in gene therapy trials.
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Dimopoulos IS, Chan S, MacLaren RE, MacDonald IM. Pathogenic mechanisms and the prospect of gene therapy for choroideremia. Expert Opin Orphan Drugs 2015; 3:787-798. [PMID: 26251765 PMCID: PMC4522943 DOI: 10.1517/21678707.2015.1046434] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
INTRODUCTION Choroideremia is a rare, X-linked disorder recognized by its specific ocular phenotype as a progressive degenerative retinopathy resulting in blindness. New therapeutic approaches, primarily based on genetic mechanisms, have emerged that aim to prevent the progressive vision loss. AREAS COVERED This article will review the research that has progressed incrementally over the past two decades from mapping to gene discovery, uncovering the presumed mechanisms triggering the retinopathy to preclinical testing of potential therapies. EXPERT OPINION While still in an evaluative phase, the introduction of gene replacement as a potential therapy has been greeted with great enthusiasm by patients, advocacy groups and the medical community.
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Affiliation(s)
- Ioannis S Dimopoulos
- University of Alberta, Department of Ophthalmology and Visual Sciences, Edmonton, Alberta, Canada
| | - Stephanie Chan
- University of Alberta, Department of Ophthalmology and Visual Sciences, Edmonton, Alberta, Canada
| | - Robert E MacLaren
- Oxford Eye Hospital and Nuffield Laboratory of Ophthalmology, John Radcliffe Hospital, Oxford, UK
- Moorfields Eye Hospital Foundation Trust, NIHR Ophthalmology Biomedical Research Centre, London, UK
| | - Ian M MacDonald
- University of Alberta, Department of Ophthalmology and Visual Sciences, Edmonton, Alberta, Canada
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14
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Zhou Q, Weis E, Ye M, Benjaminy S, MacDonald IM. An internet-based health survey on the co-morbidities of choroideremia patients. Ophthalmic Physiol Opt 2013; 33:157-63. [PMID: 23297843 DOI: 10.1111/opo.12023] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2011] [Accepted: 12/09/2012] [Indexed: 01/13/2023]
Abstract
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.
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Affiliation(s)
- Qi Zhou
- Department of Ophthalmology, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, China
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15
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Huang AS, Kim LA, Fawzi AA. Clinical characteristics of a large choroideremia pedigree carrying a novel CHM mutation. ACTA ACUST UNITED AC 2012; 130:1184-9. [PMID: 22965595 DOI: 10.1001/archophthalmol.2012.1117] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To describe a large family with a novel mutation in CHM. METHODS Family members were characterized using clinical examination, wide-field fundus photography, wide-field autofluorescence, and spectral domain optical coherence tomography. The CHM mutation was identified with the National Institutes of Health-sponsored eyeGene program. RESULTS A novel nonsense CHM mutation (T1194G), resulting in a premature stop (Y398X) and loss of the final one-third C-terminal portion of the protein, was identified. A large pedigree was generated from information provided by the twice-married proband. Seven men (aged 27-39 years) and 7 women (aged 22-89 years) were evaluated. Affected men showed characteristic peripheral chorioretinal atrophy with islands of macular sparing. Female carriers exhibited a wide range of variability, from mild pigmentary alterations to significant chorioretinal atrophy with severe vision loss. Older women tended to have a more severe phenotype. Autofluorescence demonstrating subfoveal loss or absence of retinal pigment epithelium correlated with vision loss in both sexes. Spectral domain optical coherence tomography demonstrated dynamic changes and remodeling of the outer retina over time, including focal thickening, drusenlike deposits, and disruption to photoreceptor inner segment and outer segment junctions in young female carriers. CONCLUSIONS CHM (T1194G) is a novel mutation that manifests a wide range of phenotypic variability in a single family with a trend toward more severe phenotypes in older female carriers. Our findings emphasize the importance of considering X-linked diseases by carefully evaluating pedigrees in women with severe manifestations of disease. CLINICAL RELEVANCE These findings demonstrate a novel CHM mutation that emphasizes severe posterior pole carrier phenotypes, age-related changes, and early choroideremia disease.
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Affiliation(s)
- Alex S Huang
- Doheny Eye Institute, Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, USA
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16
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Serum Biomarkers and Trafficking Defects in Peripheral Tissues Reflect the Severity of Retinopathy in Three Brothers Affected by Choroideremia. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2011; 723:381-7. [DOI: 10.1007/978-1-4614-0631-0_49] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
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17
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Perez-Cano HJ, Garnica-Hayashi RE, Zenteno JC. CHM gene molecular analysis and X-chromosome inactivation pattern determination in two families with choroideremia. Am J Med Genet A 2009; 149A:2134-40. [PMID: 19764077 DOI: 10.1002/ajmg.a.32727] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Choroideremia is an X-linked recessive retinal dystrophy characterized by progressive loss of the photoreceptor, the retinal pigment epithelium, and the choriocapillaris layers which ultimately can result in blindness by the fifth decade of life. The disease is caused by mutations in the gene CHM, which encodes a protein involved in the regulation of intracellular vesicular traffic. Typically, hemizygous males are affected by the disease and female carriers are asymptomatic with only a diffuse mottled pattern of hyperpigmentation on funduscopy. Uncommon instances of fully affected females have been described previously and these cases are proposed to arise from an skewed Lyonization mechanism preferentially inactivating the X chromosome carrying the normal CHM allele. In this work, the clinical and molecular features of two Mexican families with choroideremia are described. A novel and a previously described CHM mutation were identified. X-chromosome inactivation assays were performed in a total of 12 heterozygous carriers from the two families. In an affected female from family A, a random X-inactivation pattern was demonstrated; on the other hand, in a female carrier from family B displaying a conspicuous pattern of pigment epithelium mottling at the peripheral retina, a skewed X-inactivation pattern was found. However, the X-chromosome preferentially inactivated in this female was the one carrying the mutated allele. Our results add to the genotypic spectrum in choroideremia and does not support a correlation between X-inactivation status and abnormal retinal phenotype in heterozygous female carriers from these two families.
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Affiliation(s)
- Hector J Perez-Cano
- Research Unit, Institute of Ophthalmology Conde De Valenciana, Mexico City, Mexico
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18
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Preising M, Ayuso C. Rab escort protein 1 (REP1) in intracellular traffic: a functional and pathophysiological overview. Ophthalmic Genet 2009; 25:101-10. [PMID: 15370541 DOI: 10.1080/13816810490514333] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The intracellular distribution of proteins, compartments, substrates, and products is an active process called intracellular traffic. Control of intracellular traffic is established by small GTP-binding proteins (Rab proteins). Rab proteins are modified by geranyl-geranyl moieties necessary for membrane association and target-protein recognition. Geranyl-geranyl groups are transferred to Rab proteins by geranyl-geranyl transferase 2 (GGTase2). GGTase2 requires Rab escort protein 1 (REP1) to bind Rab proteins. REP1 null mutations underlie an X-linked retinal degeneration called choroideremia (CHM). This review summarizes the current biochemical and clinical knowledge on REP1 and CHM.
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Affiliation(s)
- Markus Preising
- Department of Pediatric Ophthalmology, Strabismology and Ophthalmogenetics, Klinikum, University of Regensburg, Germany.
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19
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Preising MN, Wegscheider E, Friedburg C, Poloschek CM, Wabbels BK, Lorenz B. Fundus Autofluorescence in Carriers of Choroideremia and Correlation with Electrophysiologic and Psychophysical Data. Ophthalmology 2009; 116:1201-9.e1-2. [DOI: 10.1016/j.ophtha.2009.01.016] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2008] [Revised: 12/12/2008] [Accepted: 01/15/2009] [Indexed: 10/20/2022] Open
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20
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Vajaranant TS, Fishman GA, Szlyk JP, Grant-Jordan P, Lindeman M, Seiple W. Detection of Mosaic Retinal Dysfunction in Choroideremia Carriers Electroretinographic and Psychophysical Testing. Ophthalmology 2008; 115:723-9. [DOI: 10.1016/j.ophtha.2007.07.032] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2007] [Revised: 06/28/2007] [Accepted: 07/30/2007] [Indexed: 11/30/2022] Open
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21
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Lai TYY, Chan WM, Lai RYK, Ngai JWS, Li H, Lam DSC. The clinical applications of multifocal electroretinography: a systematic review. Surv Ophthalmol 2007; 52:61-96. [PMID: 17212991 DOI: 10.1016/j.survophthal.2006.10.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Multifocal electroretinography (mfERG) is an investigation that can simultaneously measure multiple electroretinographic responses at different retinal locations by cross-correlation techniques. mfERG therefore allows topographic mapping of retinal function in the central 40-50 degrees of the retina. The strength of mfERG lies in its ability to provide objective assessment of the central retinal function at different retinal areas within a short duration of time. Since the introduction of mfERG in 1992, mfERG has been applied in a large variety of clinical settings. This article reviews the clinical applications of mfERG based on the currently available evidence. mfERG has been found to be useful in the assessment of localized retinal dysfunction caused by various acquired or hereditary retinal disorders. The use of mfERG also enabled clinicians to objectively monitor the treatment outcomes as the changes in visual functions might not be reflected by subjective methods of assessment. By changing the stimulus, recording, and analysis parameters, investigation of specific retinal electrophysiological components can be performed topographically. Further developments and consolidations of these parameters will likely broaden the use of mfERG in the clinical setting.
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Affiliation(s)
- Timothy Y Y Lai
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, People's Republic of China
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22
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Bozbeyoglu S, Fishman GA, Stone EM, MacDonald IM, Streb LM. De novo mutation in a choroideremia carrier. Retin Cases Brief Rep 2007; 1:182-184. [PMID: 25390790 DOI: 10.1097/icb.0b013e31804d1de0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE To describe a de novo gene mutation in a female patient with clinically characteristic findings of choroideremia (CHM). METHODS Determination of best-corrected visual acuity, fundus examination, visual field analysis, and electroretinography were performed on a female patient with an advanced CHM phenotype. Blood samples were obtained from the patient and both her parents, and direct genomic sequencing for DNA analysis was performed on the blood samples. RESULTS A single base-pair sequence change was identified in codon 293 in exon 7 (R293X) of the CHM gene in the proband. This mutation was not found to occur in her clinically unaffected parents. CONCLUSION These findings document that a de novo point mutation should be considered when an isolated female family member is found to have CHM.
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Affiliation(s)
- Simge Bozbeyoglu
- From the *Department of Ophthalmology and Visual Sciences, University of Illinois at Chicago, Chicago, Illinois; the †Department of Ophthalmology and Visual Sciences, and ‡The Howard Hughes Medical Institute at the University of Iowa, Iowa City, Iowa; and the §Department of Ophthalmology, University of Alberta, Edmonton, Alberta, Canada
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23
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Renner AB, Kellner U, Cropp E, Preising MN, MacDonald IM, van den Hurk JAJM, Cremers FPM, Foerster MH. Choroideremia: variability of clinical and electrophysiological characteristics and first report of a negative electroretinogram. Ophthalmology 2006; 113:2066.e1-10. [PMID: 16935340 DOI: 10.1016/j.ophtha.2006.05.045] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2005] [Revised: 03/30/2006] [Accepted: 05/26/2006] [Indexed: 10/24/2022] Open
Abstract
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.
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Affiliation(s)
- Agnes B Renner
- Department of Ophthalmology, Charité Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany.
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Tolmachova T, Anders R, Abrink M, Bugeon L, Dallman MJ, Futter CE, Ramalho JS, Tonagel F, Tanimoto N, Seeliger MW, Huxley C, Seabra MC. Independent degeneration of photoreceptors and retinal pigment epithelium in conditional knockout mouse models of choroideremia. J Clin Invest 2006; 116:386-94. [PMID: 16410831 PMCID: PMC1326146 DOI: 10.1172/jci26617] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2005] [Accepted: 11/01/2005] [Indexed: 01/09/2023] Open
Abstract
Choroideremia (CHM) is an X-linked degeneration of the retinal pigment epithelium (RPE), photoreceptors, and choroid, caused by loss of function of the CHM/REP1 gene. REP1 is involved in lipid modification (prenylation) of Rab GTPases, key regulators of intracellular vesicular transport and organelle dynamics. To study the pathogenesis of CHM and to develop a model for assessing gene therapy, we have created a conditional mouse knockout of the Chm gene. Heterozygous-null females exhibit characteristic hallmarks of CHM: progressive degeneration of the photoreceptors, patchy depigmentation of the RPE, and Rab prenylation defects. Using tamoxifen-inducible and tissue-specific Cre expression in combination with floxed Chm alleles, we show that CHM pathogenesis involves independently triggered degeneration of photoreceptors and the RPE, associated with different subsets of defective Rabs.
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Affiliation(s)
- Tanya Tolmachova
- Molecular and Cellular Medicine Section, Division of Biomedical Sciences, Imperial College London, London, United Kingdom
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