Antisense Oligonucleotide-based Splice Correction for USH2A-associated Retinal Degeneration Caused by a Frequent...

Area of Science:

• Genetics and Molecular Biology
• Ophthalmology
• Neurology

Background:

• Usher syndrome (USH) is the leading cause of inherited deaf-blindness.
• Mutations in the USH2A gene account for up to 50% of USH cases worldwide.
• Vision loss in USH is currently untreatable, while hearing loss can be managed.

Purpose of the Study:

• To investigate the therapeutic potential of antisense oligonucleotides (AONs) for Usher syndrome.
• To correct aberrant pre-mRNA splicing caused by the deep-intronic USH2A mutation c.7595-2144A>G.
• To explore AONs as a potential treatment for USH2A-associated retinitis pigmentosa.

Main Methods:

• Utilized engineered 2'-O-methylphosphorothioate antisense oligonucleotides (AONs).
• Targeted the PE40 pseudoexon splice acceptor site and exonic splice enhancer regions.
• Employed patient-derived fibroblasts and a minigene splice assay to evaluate splicing correction.

Main Results:

• AONs demonstrated significant potential in correcting USH2A pre-mRNA splicing defects.
• Splice correction was observed in both patient fibroblasts and the minigene assay.
• A non-binding sense oligonucleotide showed no effect on splicing, confirming AON specificity.

Conclusions:

• AON-based splice correction is a viable strategy for treating USH2A-associated retinitis pigmentosa.
• This approach offers a promising avenue for developing future therapies for Usher syndrome.
• Targeting the c.7595-2144A>G mutation with AONs could restore functional USH2A protein production.