Basamat AlMoallem^1,2

¹Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia
²Department of Ophthalmology, King Saud University Medical City (KSUMC), Riyadh, Saudi Arabia

*Corresponding Author: Basamat AlMoallem, Department of Ophthalmology, College of Medicine, King Saud University, King Abdul-Aziz University Hospital, King Abdul Aziz Rd, Al Malaz, Riyadh, Saudi Arabia.

Received: September 28, 2023; Published: October 23, 2023

Abstract

Purpose: This study aimed to establish phenotype- genotype correlations in a unique cohort of thirteen patients from eight unrelated consanguineous Saudi families with variable inherited retinal phenotypes caused by ABCA4 mutations.

Methods: A detailed ophthalmological assessment followed by next-generation sequencing (NGS) screening using vision panel was performed in the affected patients. Reference sequence (ABCA4): NM_000350.

Results: Clinically, all patients had reduced visual acuity and nystagmus documented in early childhood. A considerable phenotypic variability of ABCA4 associated disease (AAD) was observed including: Stargardt disease in 2/13 (15%), Retinitis Pigmentosa in 5/13 (39%) and Cone- Rod dystrophy in 6/13 (46%) and). Genetically; potentially eight distinct homozygous ABCA4 mutations were identified in all the studied patients (100%), five of which are novel.

Conclusion: Our study represents a unique cohort of patients originating from consanguineous families with variable retinal phenotypes caused by known and novel recessive ABCA4 mutations. This study expands the phenotypic – genotypic spectrum of AAD and provides an accurate genetic diagnosis that paves the gates for the opportunity of gene-based therapies in AAD within the scope of precision medicine

Keywords: ABCA4; Stargardt Disease; Mutation; Cone-Rod Dystrophy; Rapid-Onset Chorioretinopathy

References

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Citation

Citation: Basamat AlMoallem. “Distinct Phenotypic Patterns of ABCA4 Associated Retinal Disease in a Unique Saudi Consanguineous Cohort". Acta Scientific Clinical Case Reports 4.11 (2023): 30-35.

Copyright

Copyright: © 2023 Basamat AlMoallem. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.