1. Novel CACNA1F pathogenic variant in pediatric incomplete X-linked CSNB: integrating portable ERG and genetic analysis.
- Author
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Wen L, Liu Y, Yang Z, Mei S, Xin Y, and Li S
- Abstract
Purpose: To report a novel hemizygous nonsense variant in the CACNA1F gene associated with congenital stationary night blindness (CSNB) in a pediatric patient, emphasizing the utility of portable electroretinography (ERG) and genetic testing in diagnosing unexplained visual impairments., Methods: The patient, a 5-year-old male, underwent comprehensive clinical evaluation, including detailed anterior segment and fundus examinations, full-field electroretinogram (ffERG) using a RETeval™ portable device, and whole exome sequencing (WES) to elucidate the genetic basis of his visual impairment. Structural modeling of the mutated protein was performed using SWISS-MODEL and PYMOL., Results: Best-corrected visual acuity was 0.4 logMAR bilaterally, with unremarkable anterior segment and fundus examinations. FFERG revealed significant abnormalities consistent with incomplete CSNB: severely reduced rod response in dark-adapted (DA) 0.01, negative waveform with b/a wave ratio < 1.0 in DA 3.0, and diminished cone response in light-adapted ERG. WES identified a novel pathogenic variant in the CACNA1F gene (c.1234G > T, p.E412*), inherited maternally. This variant introduces a premature stop codon at position 412, likely resulting in a truncated CACNA1F protein., Conclusions: This case highlights the importance of comprehensive clinical assessments and genetic testing in pediatric patients with unexplained visual impairments, revealing a novel CACNA1F variant that expands our understanding of CSNB. The use of a portable ERG device proved particularly valuable in assessing retinal function in this young patient. Further investigations are warranted to elucidate the clinical implications of this novel pathogenic variant., Competing Interests: Declarations. Conflict of Interest: The authors declare that they have no competing interests. Informed consent: Informed consent was obtained from the patient’s parents. Human rights: The study received approval from the Medical Ethics Committee of Xiang'an Hospital of Xiamen University (XAHLL2022028, March 7, 2022), in accordance with the Declaration of Helsinki., (© 2024. The Author(s).)
- Published
- 2024
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