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Navigating MARRVEL, a Web-Based Tool that Integrates Human Genomics and Model Organism Genetics Information
Published on: August 15, 2019
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The phenotypic spectrum of CEP250 gene variants
Cécile Courdier1, Claire-Marie Dhaenens2, Olivier Grunewald2
1Service de Génétique Médicale, CHU de Bordeaux, Bordeaux, France.
Ophthalmic Genetics
|November 29, 2024
Summary
Pathogenic variants in CEP250 cause atypical Usher syndrome, characterized by sensorineural hearing loss and photoreceptor dysfunction. This study details 7 cases, highlighting the disease
Area of Science:
- Genetics
- Ophthalmology
- Audiology
Background:
- Usher syndrome classically involves hearing loss, retinitis pigmentosa, and vestibular issues.
- Atypical Usher syndrome linked to CEP250 variants presents with hearing loss and photoreceptor dysfunction, lacking vestibular signs.
- Only 19 cases of CEP250-related disease have been previously reported.
Purpose of the Study:
- To provide detailed clinical and genetic descriptions of 7 individuals with CEP250-related disease.
- To review existing literature on CEP250-related disease to better understand its severity and progression.
- To offer new insights into the clinical spectrum and natural history of CEP250-related disorders.
Main Methods:
- Retrospective recruitment of 7 unrelated individuals with CEP250 pathogenic variants.
- Genetic testing including targeted gene panels and whole genome sequencing.
- Clinical data collection and literature review.
Main Results:
- Five out of seven patients presented with both retinal dystrophy and sensorineural hearing loss (SNHL).
- Two patients showed isolated hearing loss or visual impairment, requiring further investigation for non-syndromic presentations.
- All analyzed patients carried isolated truncating variants in CEP250.
Conclusions:
- CEP250 variants are linked to post-lingual SNHL and progressive photoreceptor dysfunction.
- Disease onset can manifest as either ocular or auditory symptoms.
- Genetic testing for Usher-related genes and ophthalmological/audiological evaluations are recommended for suspected cases.
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