How gene therapy and CRISPR are helping to eye diseases?
Sara Taghizadeh1 , Seyed Farzad Mohammadi1 *
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences
Abstract: Clustered regularly interspaced short palindromic repeat-associated 9 (CRISPR-Cas9) nuclease is a recently discovered, robust gene-editing platform derived from a bacterial adaptive immune defense system. This system can be efficiently programmed to modify the genome of eukaryotic cells via an RNA-guided DNA cleavage module and has emerged as a potential alternative to conventional gene therapy methods (ZFNs and TALENs) to induce targeted genetic modifications.
Methods: Gene therapy involves inserting the correct copy of a gene into cells that have a mistake in the genetic sequence of that gene, recovering the normal function of the protein in the cell. The eye is an ideal organ for testing new therapeutic approaches, including CRISPR. That is because the eye is the most exposed part of our brain and thus is easily accessible.
The second reason is that retinal tissue in the eye is shielded from the body’s defense mechanism, which would otherwise consider the injected material used in gene therapy as foreign and mount a defensive attack response. Such a response would destroy the benefits associated with the treatment.
Results: In recent years, with the advancement of gene sequencing technology, it is more explicit to make the genetic diagnosis of a variety of hereditary eye diseases, such as congenital cataract, congenital glaucoma, retinitis pigmentosa (RP), congenital corneal dystrophy, Leber congenital amaurosis (LCA), retinoblastoma (RB), and Usher syndrome.
Also, CRISPR/Cas9 has already been used to generate animal models of some hereditary eye diseases.
Furthermore, breakthrough gene therapy studies paved the way to the first-ever Food and Drug Administration-approved gene therapy drug, Luxturna TM, for a devastating childhood blindness disease, Leber congenital amaurosis Type 2.
Conclusion: Genome editing has extended our ability to elucidate the contribution of genetics to disease by promoting the creation of more accurate cellular and animal models of pathological processes and has begun to show extraordinary potential in a variety of fields, ranging from basic research to applied biotechnology and biomedical research.
