Abstract
Objective
Choroideremia (CHM) is an X-linked chorioretinal dystrophy caused by variants in the CHM gene. The aim of this study was to report the clinical and genetic features of a cohort of affected males with CHM and establish the relationship between best correct visual acuity (BCVA) and age.
Method
Twenty-seven patients from 24 unrelated families underwent detailed ophthalmic examinations and comprehensive molecular genetic analysis. We combined the 27 patients in our own cohort with 68 Chinese patients from six previously reported studies to determine a transition age for BCVA rapid decline in 95 patients.
Results
Twenty-three causal (9 novel) CHM variants were identified in the 27 patients, who had a mean age of 30.5 ± 17.4 years and a mean BCVA (LogMAR) of 0.61 ± 0.79. Patients at different disease stages showed different extents of retinal pigment epithelium (RPE) and choroid abnormalities. Central retinal optical coherence tomography (OCT) scanning revealed defects in the ellipsoid zone and RPE in all patients and outer retinal tubulations in 75%. The 95 patients had a mean age of 33.27 ± 16.27 years and an average (LogMAR) of 0.72 ± 0.82. The BCVA did not decline rapidly before age 25, but decreased at a mean rate of 0.037logMAR/year after that age.
Conclusions
Our results indicated Chinese patients with CHM variants have a younger transition age for rapid BCVA decline than previously reported for other ethnic groups. Central retinal OCT scanning can identify different abnormalities in the retinal structures, and these might be used as other parameters for monitoring disease progression in patients with CHM.
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References
Moosajee M, Ramsden SC, Black GC, Seabra MC, Webster AR, Clinical utility gene card for: choroideremia. Eur J Hum Genet. 2014; 22.
Dimopoulos IS, Radziwon A, St Laurent CD, MacDonald IM. Choroideremia. Curr Opin Ophthalmol. 2017;28:410–5.
Dimopoulos IS, Chan S, MacLaren RE, MacDonald IM. Pathogenic mechanisms and the prospect of gene therapy for choroideremia. Expert Opin Orphan Drugs. 2015;3:787–98.
Murro V, Mucciolo DP, Passerini I, Palchetti S, Sodi A, Virgili G, et al. Retinal dystrophy and subretinal drusenoid deposits in female choroideremia carriers. Graefes Arch Clin Exp Ophthalmol. 2017;255:2099–111.
Corbeel L, Freson K. Rab proteins and Rab-associated proteins: major actors in the mechanism of protein-trafficking disorders. Eur J Pediatr. 2008;167:723–9.
Simunovic MP, Jolly JK, Xue K, Edwards TL, Groppe M, Downes SM, et al. The spectrum of CHM gene mutations in choroideremia and their relationship to clinical phenotype. Invest Ophthalmol Vis Sci. 2016;57:6033–9.
Pennesi ME, Birch DG, Duncan JL, Bennett J, Girach A. Choroideremia: retinal degeneration with an unmet need. Retina. 2019;39:2059–69.
Lam BL, Davis JL, Gregori NZ, MacLaren RE, Girach A, Verriotto JD, et al. Choroideremia gene therapy phase 2 clinical trial: 24-month results. Am J Ophthalmol. 2019;197:65–73.
Roberts MF, Fishman GA, Roberts DK, Heckenlively JR, Weleber RG, Anderson RJ, et al. Retrospective, longitudinal, and cross sectional study of visual acuity impairment in choroideraemia. Br J Ophthalmol. 2002;86:658–62.
Freund PR, Sergeev YV, MacDonald IM. Analysis of a large choroideremia dataset does not suggest a preference for inclusion of certain genotypes in future trials of gene therapy. Mol Genet Genom Med. 2016;4:344–58.
Di Iorio V, Esposito G, De Falco F, Boccia R, Fioretti T, Colucci R, et al. CHM/REP1 transcript expression and loss of visual function in patients affected by choroideremia. Invest Ophthalmol Vis Sci. 2019;60:1547–55.
Shen LL, Ahluwalia A, Sun M, Young BK, Grossetta Nardini HK, Del Priore LV. Long-term natural history of visual acuity in eyes with choroideremia: a systematic review and meta-analysis of data from 1004 individual eyes. Br J Ophthalmol. 2020;105:271–8.
Han X, Wu S, Li H, Zhu T, Wei X, Zhou Q, et al. Cincal charateristic and melecualr genetic analyis of a cohort of Chinese patients with choroideremia. Retina. 2020;40:2240–53.
Cai XB, Huang XF, Tong Y, Lu QK, Jin ZB. Novel CHM mutations identified in Chinese families with Choroideremia. Sci Rep. 2016;6:35360.
Guo H, Li J, Gao F, Li J, Wu X, Liu Q. Whole-exome sequencing reveals a novel CHM gene mutation in a family with choroideremia initially diagnosed as retinitis pigmentosa. BMC Ophthalmol. 2015;15:85.
Lin Y, Liu X, Luo L, Qu B, Jiang S, Yang H, et al. Molecular analysis of the choroideremia gene related clinical findings in two families with choroideremia. Mol Vis. 2011;17:2564–9.
Gao FJ, Tian GH, Hu FY, Wang DD, Li JK, Chang Q, et al. Next-generation sequencing-based clinical diagnosis of choroideremia and comprehensive mutational and clinical analyses. BMC Ophthalmol. 2020;20:212.
Dan H, Li T, Lei X, Huang X, Xing Y, Shen Y. Whole exome sequencing of a family revealed a novel variant in the CHM gene, c.22delG p.(Glu8Serfs*4), which co-segregated with choroideremia. Biosci Rep. 2020;40:BSR20200067.
Krill AE, Hereditary retinal and choroidal diseases. Harper & Row Press: Hagerstown, USA, 1972.
Sun T, Xu K, Ren Y, Xie Y, Zhang X, Tian L, et al. Comprehensive molecular screening in chinese usher syndrome patients. Invest Ophthalmol Vis Sci. 2018;59:1229–37.
Talevich E, Shain AH, Botton T, Bastian BC. CNVkit: genome-wide copy number detection and visualization from targeted DNA sequencing. PLoS Comp Biol. 2016;12:e1004873.
Dong B, Chen J, Zhang X, Pan Z, Bai F, Li Y. Two novel PRP31 premessenger ribonucleic acid processing factor 31 homolog mutations including a complex insertion-deletion identified in Chinese families with retinitis pigmentosa. Mol Vis. 2013;19:2426–35.
Radziwon A, Arno G, D KW, McDonagh EM, Baple EL, Webb-Jones K, et al. Single-base substitutions in the CHM promoter as a cause of choroideremia. Hum Mutat. 2017;38:704–15.
Coussa RG, Kim J, Traboulsi EI. Choroideremia: effect of age on visual acuity in patients and female carriers. Ophthalmic Genet. 2012;33:66–73.
Heon E, Alabduljalil T, McGuigan DB III, Cideciyan AV, Li S, Chen S, et al. Visual function and central retinal structure in choroideremia. Invest Ophthalmol Vis Sci. 2016;57:OCT377–387.
Hayashi T, Kameya S, Mizobuchi K, Kubota D, Kikuchi S, Yoshitake K, et al. Genetic defects of CHM and visual acuity outcome in 24 choroideremia patients from 16 Japanese families. Sci Rep. 2020;10:15883.
van Schuppen SM, Talib M, Bergen AA, Ten Brink JB, Florijn RJ, Boon CJF, et al. Long-term follow-up of patients with choroideremia with scleral pits and tunnels as a novel observation. Retina. 2018;38:1713–24.
Li Q, Li Y, Zhang X, Xu Z, Zhu X, Ma K, et al. Utilization of fundus autofluresence, spectral domain optical coherence tomography, and enhanced depth images in the charaterization of Bietti crystalline dystrophy in different stages. Retina. 2015;35:2074–84.
Khan KN, Islam F, Moore AT, Michaelides M. Clinical and genetic features of choroideremia in childhood. Ophthalmology. 2016;123:2158–65.
Ramsden SC, O’Grady A, Fletcher T, O’Sullivan J, Hart-Holden N, Barton SJ, et al. A clinical molecular genetic service for United Kingdom families with choroideraemia. Eur J Med Genet. 2013;56:432–8.
van den Hurk JA, Schwartz M, van Bokhoven H, van de Pol TJ, Bogerd L, Pinckers AJ, et al. Molecular basis of choroideremia (CHM): mutations involving the Rab escort protein-1 (REP-1) gene. Hum Mutat. 1997;9:110–7.
Acknowledgements
This study was supported by the National Key R&D Program of China (2017YFA0104103) and the High-level Talents training plan of the health system of Beijing (No. 2013-2-021). The funding organizations had no role in designing or conducting this research.
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YS participated in study design, data collection and analysis, and manuscript preparation. CC contributed in collecting clinical data of patients, performing molecular experiments analysis, YX, TS, and XK participated in data collection and analysis. YL participated in the study design and revised the manuscript critically for important intellectual content. All authors approved the final version.
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Song, Y., Chen, C., Xie, Y. et al. Clinical and genetic findings in a Chinese cohort with choroideremia. Eye 37, 459–466 (2023). https://doi.org/10.1038/s41433-022-01950-6
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DOI: https://doi.org/10.1038/s41433-022-01950-6