# Clinical and Genetic Features of Autosomal Recessive Bestrophinopathy: A Case Series from a Vietnamese Cohort

## TL;DR

This study reports on nine Vietnamese patients with a rare eye disease, identifying common symptoms and new genetic mutations linked to the condition.

## Contribution

The study expands the known genetic variants of autosomal recessive bestrophinopathy, including a novel BEST1 mutation in a Vietnamese cohort.

## Key findings

- All nine patients showed vitelliform lesions, subretinal deposits, and retinal fluid.
- The most common BEST1 gene variants were p.(A195V) and p.(R200*), with a novel variant p.(K289*) identified.
- Clinical features included diffuse macular hyperfluorescence and hyperopia in most patients.

## Abstract

Objectives: This study aims to describe the clinical features and genetic findings of nine Vietnamese patients with autosomal recessive bestrophinopathy. Methods: This retrospective and cross-sectional study included individuals diagnosed with autosomal recessive bestrophinopathy at the Eye Clinic, Vietnam National Geriatric Hospital between May 2024 and April 2025. The patients underwent a visual acuity assessment, retinal multimodal imaging, and molecular testing through BEST1 gene sequencing. Results: Nine patients from seven unrelated families were included. The mean age was 38.6 years (range: 14.1–79.6). Visual acuity ranged from 20/20 to 20/125. All patients showed vitelliform lesions, subretinal deposits, and both intraretinal and subretinal fluid. Other main features included diffuse macular hyperfluorescence and hyperopia. Less common clinical features encompassed glaucoma, retinoschisis, outer retinal thinning, serous retinal detachment, retinal thickening, and thinning of the retinal pigment epithelium. Compound heterozygous or homozygous variants were detected in all patients. Among the five identified BEST1 variants, the most frequent were p.(A195V) and p.(R200*). One novel variant, p.(K289*), was detected. Conclusions: The main clinical retinal features of nine Vietnamese patients with autosomal recessive bestrophinopathy included vitelliform lesions, subretinal deposits, retinal fluid, and diffuse macular hyperfluorescence. The most common variants were p.(A195V) and p.(R200*). Additionally, the identification of various compound heterozygotes and a novel BEST1 variant expands the mutation spectrum of the disease.