Department of Ophthalmology and Vision Science, Eye and ENT Hospital of Fudan University, 83 Fenyang Rd, Shanghai, 200031, China.
Key Laboratory of Myopia of State Health Ministry, and Key Laboratory of Visual Impairment and Restoration of Shanghai, Shanghai, China.
Hum Genomics. 2024 Mar 1;18(1):22. doi: 10.1186/s40246-024-00589-6.
To report newly found TSPAN12 mutations with a unique form of familial exudative vitreoretinopathy (FEVR) and find out the possible mechanism of a repeated novel intronic variant in TSPAN12 led to FEVR.
Nine TSPAN12 mutations with a unique form of FEVR were detected by panel-based NGS. MINI-Gene assay showed two splicing modes of mRNA that process two different bands A and B, and mutant-type shows replacement with the splicing mode of Exon11 hopping. Construction of wild-type and mutant TSPAN12 vector showed the appearance of premature termination codons (PTC). In vitro expression detection showed significant down-regulated expression level of TSPAN12 mRNAs and proteins in cells transfected with mutant vectors compared with in wild-type group. On the contrary, translation inhibitor CHX and small interfering RNA of UPF1 (si-UPF1) significantly increased mRNA or protein expression of TSPAN12 in cells transfected with the mutant vectors.
Nine mutations in TSPAN12 gene are reported in 9 FEVR patients with a unique series of ocular abnormalities. The three novel TSPAN12 mutations trigger NMD would cause the decrease of TSPAN12 proteins that participate in biosynthesis and assembly of microfibers, which might lead to FEVR, and suggest that intronic sequence analysis might be a vital tool for genetic counseling and prenatal diagnoses.
报道一种具有独特表现形式的家族性渗出性玻璃体视网膜病变（FEVR）的新发现 TSPAN12 突变，并找出 TSPAN12 中重复出现的新型内含子变异导致 FEVR 的可能机制。
通过基于面板的 NGS 检测到 9 个具有独特 FEVR 形式的 TSPAN12 突变。MINI-Gene 检测显示两种不同大小的 mRNA 剪接模式 A 和 B，突变型显示外显子 11 跳跃的剪接模式替代。野生型和突变型 TSPAN12 载体的构建显示出提前终止密码子（PTC）的出现。体外表达检测显示，与野生型组相比，转染突变载体的细胞中 TSPAN12 mRNA 和蛋白的表达水平显著下调。相反，翻译抑制剂 CHX 和 UPF1 的小干扰 RNA（si-UPF1）显著增加了转染突变载体的细胞中 TSPAN12 的 mRNA 或蛋白表达。
在 9 名具有独特眼部异常系列的 FEVR 患者中报告了 9 个 TSPAN12 基因中的突变。三个新的 TSPAN12 突变触发 NMD 会导致参与微纤维生物合成和组装的 TSPAN12 蛋白减少，这可能导致 FEVR，并表明内含子序列分析可能是遗传咨询和产前诊断的重要工具。
