Centre for Regenerative Medicine, Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy.
Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy.
Am J Hum Genet. 2021 Feb 4;108(2):295-308. doi: 10.1016/j.ajhg.2021.01.006. Epub 2021 Jan 27.
Retinitis pigmentosa (RP) is a group of progressive retinal degenerations of mostly monogenic inheritance, which cause blindness in about 1:3,500 individuals worldwide. Heterozygous variants in the rhodopsin (RHO) gene are the most common cause of autosomal dominant RP (adRP). Among these, missense variants at C-terminal proline 347, such as p.Pro347Ser, cause severe adRP recurrently in European affected individuals. Here, for the first time, we use CRISPR/Cas9 to selectively target the p.Pro347Ser variant while preserving the wild-type RHO allele in vitro and in a mouse model of adRP. Detailed in vitro, genomic, and biochemical characterization of the rhodopsin C-terminal editing demonstrates a safe downregulation of p.Pro347Ser expression leading to partial recovery of photoreceptor function in a transgenic mouse model treated with adeno-associated viral vectors. This study supports the safety and efficacy of CRISPR/Cas9-mediated allele-specific editing and paves the way for a permanent and precise correction of heterozygous variants in dominantly inherited retinal diseases.
色素性视网膜炎（RP）是一组主要为单基因遗传的进行性视网膜退行性疾病，导致全世界约有 1/3500 的人失明。视紫红质（RHO）基因的杂合变体是常染色体显性遗传 RP（adRP）的最常见原因。在这些变体中，C 末端脯氨酸 347 处的错义变体，如 p.Pro347Ser，经常在欧洲受影响个体中引起严重的 adRP。在这里，我们首次使用 CRISPR/Cas9 在体外和 adRP 的小鼠模型中选择性地靶向 p.Pro347Ser 变体，同时保留野生型 RHO 等位基因。对 rhodopsin C 末端编辑的详细体外、基因组和生化特征表明，p.Pro347Ser 表达的安全下调导致用腺相关病毒载体治疗的转基因小鼠模型中光感受器功能部分恢复。这项研究支持 CRISPR/Cas9 介导的等位基因特异性编辑的安全性和有效性，并为显性遗传性视网膜疾病中杂合变体的永久性和精确校正铺平了道路。
