Department of Ophthalmology, Eye and ENT Hospital, Fudan University, 83 Fenyang Rd., Shanghai 200031, China.
Eye Institute, Eye and ENT Hospital, Fudan University, Shanghai, China.
Eur J Ophthalmol. 2024 Nov;34(6):1750-1760. doi: 10.1177/11206721241240503. Epub 2024 Mar 28.
Relative anterior microphthalmos (RAM) is a rare congenital defect associated with severe vision impairment that is primarily caused by genetic alterations. The purpose of this study was to identify the causative genetic variants in two Chinese families with RAM with an autosomal recessive inheritance pattern.
DNA samples were obtained from two probands and their family members. Targeted next-generation sequencing (NGS) was used to screen 425 genes associated with inherited eye diseases to identify possible disease-causing variants in the two patients. Sanger sequencing was subsequently used to validate the results in both families.
The targeted NGS panel identified potentially causative novel variants of the latent transforming growth factor beta binding protein 2 () gene in the two RAM families: a missense variant (c.2771C > T; p.Ala924Val) and an intronic variant (c.4582 + 9A > G) in Family A and a different missense variant (c.5239C > A; p.Arg1747Ser) and a synonymous variant (c.951G > A; p.Pro317Pro) in Family B. These four novel variants all cosegregated with the disease phenotype.
To our knowledge, this is the first study to report novel gene variants related to RAM. Considering the importance of LTBP2 in ocular development, we provide initial insights into the potential pathogenic mechanisms of LTBP2 in RAM.
相对前小眼球症(RAM)是一种罕见的先天性缺陷,与严重的视力损害有关,主要由遗传改变引起。本研究的目的是在两个具有常染色体隐性遗传模式的 RAM 中国家系中鉴定导致这种疾病的遗传变异。
从两个先证者及其家系成员中获取 DNA 样本。采用靶向下一代测序(NGS)对与遗传性眼病相关的 425 个基因进行筛选,以鉴定两个患者中可能的致病变异。随后对两个家系进行 Sanger 测序以验证结果。
靶向 NGS 面板在两个 RAM 家系中鉴定出潜伏转化生长因子β结合蛋白 2(LTBP2)基因的潜在致病新变异:家系 A 中的错义变异(c.2771C>T;p.Ala924Val)和内含子变异(c.4582+9A>G),以及家系 B 中的不同错义变异(c.5239C>A;p.Arg1747Ser)和同义变异(c.951G>A;p.Pro317Pro)。这四个新变异均与疾病表型共分离。
据我们所知,这是首次报道与 RAM 相关的新 LTBP2 基因变异。鉴于 LTBP2 在眼发育中的重要性,我们初步探讨了 LTBP2 在 RAM 中的潜在致病机制。