Novel BEST1 Mutations and Special Clinical Features of Best Vitelliform Macular Dystrophy

Purpose: To describe the clinical features and to analyze BEST1 mutations in patients with Best vitelliform macular dystrophy (BVMD). Methods: Thirteen individuals affected by BVMD from 6 unrelated Chinese families were studied. Complete ophthalmological examinations were performed, and the BEST1 gene was screened in all participants and 100 controls. Follow-ups were arranged within 12 months. Results: All 6 probands showed typical fundus appearances of BVMD. One of the 6 had a history of angle closure glaucoma, and another showed a unilateral focal choroidal excavation on optical coherence tomography. One patient experienced progression of the macular lesion during the follow-up. The asymptomatic mutation carriers had normal fundus but abnormal Arden ratios on electro-oculograms. Besides 4 previously reported mutations (p.Ser16Phe, p.Ser144Asn, p.Glu292Lys, p.Glu300Lys), 2 novel disease-causing mutations (p.Thr307Asp, p.Arg47His) were identified, of which p.Arg47His has been reported in adult-onset vitelliform macular dystrophy. Conclusions: Our findings have expanded the mutational and clinical spectrum of BVMD in a Chinese population. Clinical presentations of angle closure glaucoma and/or focal choroidal excavation may be related to BVMD, underlining the necessity of multimodal studies and risk assessment of angle closure glaucoma in BEST1 mutation carriers. BVMD and adult-onset vitelliform macular dystrophy may share a common etiology in some cases.