Bascom Palmer Eye Institute, University of Miami, Miami, Florida, USA.
Ophthalmic Genet. 2023 Dec;44(6):602-605. doi: 10.1080/13816810.2023.2175873. Epub 2023 Feb 7.
The aim of the study is to present a rare case of Foveal Hypoplasia, Optic Nerve Decussation defects, and Anterior segment dysgenesis (FHONDA) confirmed by genetic testing with two separate pathogenic mutations in the gene.
This was a case report.
A 3-month-old female presented to a neuro-ophthalmology clinic with nystagmus. Her past medical and family history was unremarkable. Her examination demonstrated horizontal pendular nystagmus and small optic nerves with foveal hypoplasia bilaterally. Neuroimaging was unremarkable. She underwent an examination under anesthesia and electroretinogram (ERG). Her anterior segment examination was normal, and dilated fundus examination demonstrated foveal hypoplasia with diffuse pigment granularity. The ERG was normal. Genetic testing revealed two mutations in the gene, p.Glu233Lys:c.697 G>A (pathogenic) and p.Asp283Ala:c.848A>C (likely pathogenic) with positive parental segregation analysis. Therefore, she was diagnosed with FHONDA.
To our knowledge, this is the first report of a patient with FHONDA who is compound heterozygous for these two mutations, which represents an expansion of the known mutational spectrum associated with this syndrome. Moreover, it may provide guidance into genetic counseling for patients and parents with these mutations.
本研究旨在报告一例经基因检测证实的伴有 基因中两个独立致病性突变的 Foveal Hypoplasia、Optic Nerve Decussation 缺陷和前节发育不良（FHONDA）的罕见病例。
这是一例病例报告。
一名 3 月龄女性因眼球震颤就诊于神经眼科诊所。其既往病史和家族史无明显异常。她的检查显示水平摆动性眼球震颤和双侧小视神经伴黄斑发育不良。神经影像学无明显异常。她接受了全身麻醉下检查和视网膜电图（ERG）检查。她的前节检查正常，散瞳眼底检查显示黄斑发育不良伴弥漫性色素颗粒。ERG 正常。基因检测显示 基因中存在两个突变，p.Glu233Lys：c.697G>A（致病性）和 p.Asp283Ala：c.848A>C（可能致病性），并经阳性父母分离分析证实。因此，她被诊断为 FHONDA。
据我们所知，这是首例报告的 FHONDA 患者，其为这两个 突变的复合杂合子，这扩大了与该综合征相关的已知突变谱。此外，它可能为携带这些突变的患者及其父母提供遗传咨询指导。
