Genetics of retinal degeneration in 2023

Authors

  • Elise Héon, MD, FRCPC
  • Ajoy Vincent, MBBS, MS, FRCSC
  • Alaa Tayyib, MD

DOI:

https://doi.org/10.58931/cect.2023.2122

Abstract

Inherited retinal degenerations (IRDs) are of great interest with the development of novel therapies, thereby allowing this group of conditions to be “actionable” for the first time.

A molecular diagnosis can be obtained in nearly 70% of cases of IRD, with over 300 IRD-linked genes having been identified to date. Numerous animal models of different genetic subtypes of IRDs replicated the human phenotypes enough to develop and test novel therapies to improve outcomes for IRD patients. The first gene replacement therapy indicated for IRD, Luxturna (voretigene neparvovec-rzyl), was approved by Health Canada in October 2020 and is now available to patients with vision loss due to inherited retinal dystrophy caused by confirmed biallelic RPE65 mutations. Clinicians from Ontario, Quebec and Alberta can now access this treatment through their province’s public health plan.

This article aims to review some basic information and present new knowledge about IRDs to allow clinicians to better understand diagnosis and disease management.

Author Biographies

Elise Héon, MD, FRCPC

Dr. Elise Héon has been staff ophthalmologist at SickKids since 1996. Her career focusses on inherited eye disorders, now mostly on inherited retinal diseases. She directs the Ocular Genetics program providing comprehensive assessment, genetic testing and counseling of patients affected with inherited retinal disorders. She became Chief of Ophthalmology in 2003 when her laboratory was moved from the Toronto Western to SickKids Research Institute. She has trained numerous students of various academic levels from around the world. Dr. Héon’s current research focusses on the genetic characterization of inherited retinal disorders when clinical genetic testing did not identify the disease-causing variant(s). Using Genome sequencing and sophisticated analytical protocol, her group has been successful in deciphering nearly 80% of cases. Dr. Héon has a specific interest in disease cause by genes affecting cilia, ciliopathy, namely Bardet Biedl syndrome. Using cells from patients and high throughput drug screening through the SPARC facility, her groups is trying to identify small molecules that may improve patient outcome. Lastly, Dr. Héon is exploring patient reported outcome measures (PROM) for IRD and especially in children, which would best represent the impact of the visual impairment on the patient daily living.

Ajoy Vincent, MBBS, MS, FRCSC

Dr. Ajoy Vincent is trained in the field of Eye Genetics and Electrophysiology. He cares for patients with isolated and complex inherited retinal dystrophies (IRDs). He also serves as the Medical Director of Visual Electrophysiology Unit (VEU) at SickKids. He is actively involved in teaching Ophthalmology residents and fellows at SickKids. Dr. Vincent’s research endeavors include discovering novel genes underlying inherited retinal dystrophies (IRDs), characterizing novel genotype-phenotype correlations in IRDs, uncovering disease pathways and mechanisms in IRDs, and conducting innovative pediatric clinical trials; all with the aim of improving patient outcomes.

Alaa Tayyib, MD

Dr. Alaa Tayyib earned her Bachelor of Medicine and Surgery from King Abdulaziz University in Saudi Arabia, followed by her ophthalmology residency training at the Saudi Ophthalmology Residency Program. She is currently completing her clinical ocular genetics and inherited retinal diseases fellowship at the University of Toronto.

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Published

2023-02-01

How to Cite

1.
Héon E, Vincent A, Tayyib A. Genetics of retinal degeneration in 2023. Can Eye Care Today [Internet]. 2023 Feb. 1 [cited 2024 May 15];2(1):15–24. Available from: https://canadianeyecaretoday.com/article/view/2-1-3

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Volume 2, Issue 1, February 2023

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