Usher Syndrome - Prospects For Gene Therapy

Prospects For Gene Therapy

Since Usher syndrome results from the loss of a gene, gene therapy that adds the proper protein back ("gene replacement") may alleviate it, provided that the added protein becomes functional. Recent studies of mouse models have shown that one form of the disease — that associated with a mutation in myosin VIIa — can be alleviated by replacing the mutant gene using a lentivirus. However, some of the mutated genes associated with Usher syndrome encode very large proteins — most notably, the USH2A and GPR98 proteins, which have roughly 6000 amino-acid residues. Gene replacement therapy for such large proteins may be difficult.