Department of Neurology and Institute of Neurology, First Affiliated Hospital, Fujian Medical University, Fuzhou, China.
Eur J Hum Genet. 2020 Jul;28(7):947-955. doi: 10.1038/s41431-020-0578-z. Epub 2020 Feb 11.
The X-linked recessive degenerative disease dystrophinopathy results from variants in the DMD gene. Given the large size and complexity of the DMD gene, molecular diagnosis for all dystrophinopathies remains challenging. Here we identified two cryptic exon retention variants caused by intronic single nucleotide variants in dystrophinopathy patients using combined RNA- and DNA-based methods. As one variant was previously unreported, we explored its likely pathogenic mechanism, via bioinformatic prediction for in silico verification of splicing. Then we constructed a minigene system harboring the variant and used morpholino modified antisense oligonucleotides (ASOs) to induce cryptic exon skipping. ASOs treatment corrected the mis-splicing in the mutant minigene system. Our study defines a novel intronic variant that can cause dystrophinopathy, and illustrates a strategy to overcome the aberrant splicing.
X 连锁隐性退行性疾病肌营养不良症是由 DMD 基因突变引起的。鉴于 DMD 基因的庞大和复杂性，所有肌营养不良症的分子诊断仍然具有挑战性。在这里，我们使用基于 RNA 和 DNA 的联合方法，在肌营养不良症患者中鉴定了两个由内含子单核苷酸变异引起的隐匿性外显子保留变异。由于其中一个变异以前没有报道过，我们通过生物信息学预测对剪接进行了计算机验证，从而探索了其可能的致病机制。然后，我们构建了一个携带该变异的小基因系统，并使用修饰的反义寡核苷酸 (ASO) 来诱导隐匿性外显子跳跃。ASO 处理纠正了突变小基因系统中的错误剪接。我们的研究定义了一种新的可引起肌营养不良症的内含子变异，并说明了克服异常剪接的策略。
