USH2A Antisense Oligonucleotides for Exon Skipping Under AAV Packaging Limits
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Solution Overview
Problem
Current treatments for Usher syndrome caused by USH2A mutations are limited, particularly due to the large size of the usherin-encoding sequence exceeding the packaging capacity of conventional gene delivery vectors, and there is a need for effective therapies to address progressive vision loss and hearing impairment.
Innovation Solution
Development of antisense oligonucleotides (ASOs) that specifically target and skip exons 30 and 31 of the USH2A gene, encoded by sequences such as SEQ ID NO: 1, to modulate splicing and produce a functional usherin protein, using viral vectors like AAV for delivery.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional gene augmentation therapy using AAV or LV vectors is used, then the packaging capacity is limited to 4.7 kb or 8 kb respectively, but the usherin-encoding sequence is 15.6 kb which exceeds this capacity
Solution Approach 1:
The invention segments the 15.6 kb usherin-encoding sequence by using antisense oligonucleotides to induce skipping of specific exons (exons 30-31), thereby producing a shortened usherin protein that fits within the packaging capacity of conventional AAV or LV vectors while still retaining functional domains
Solution Approach 2:
The invention extracts and removes specific exons (30-31) from the usherin-encoding sequence through ASO-mediated exon skipping, eliminating the repetitive fibronectin type III domain to reduce the overall sequence length to fit viral vector packaging limits
2Quantity of substance
If ASO-induced exon skipping is used to reduce sequence size, then the usherin protein can be packaged in conventional vectors, but the protein structure is altered by removing fibronectin type III domains
Solution Approach 1:
The invention applies local quality by selectively removing only the repetitive fibronectin type III domains (exons 30-31) while preserving other critical functional domains of usherin, thereby maintaining local structural integrity where needed while reducing overall size
Solution Approach 2:
The invention changes the parameter of protein length by inducing exon skipping to produce a shortened usherin isoform that lacks specific domains but retains essential functional regions, balancing size reduction with structural preservation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The dual exon skipping approach with ASOs results in a shortened usherin protein lacking a repetitive fibronectin type III domain, showing promise in halting or delaying progressive vision loss in USH2A-associated retinitis pigmentosa.
Implementation Method 1
antisense oligonucleotides (ASOs) that specifically target and skip exons 30 and 31 of the USH2A gene
Implementation Method 2
ASOs are applied to correct aberrant pre-mRNA splicing or to remove native in-frame exons harboring recurrent loss-of-function mutations
Data Source
AI summary
The invention relates to the fields of medicine and immunology. In particular, it relates to novel antisense oligonucleotides that may be used in the treatment, prevention and/or delay of an USH2A related disease or condition.