ATGEN

GSD Type1A occurs when the G6PC enzyme can’t function properly as a result of over 100mutations in the G6PC gene. Instead of focusing on these mutations individually, we‘ll transfer the functional G6PC gene to the mutated cells to create a treatment. Alternatively, we’ll transfer a more active isoform of G6PC(S298C) and use the more effective one in our project by comparing two of them. We chose lentiviral vectors with high carrying capacity to transfer the gene at once. We used integrase defective 3rd generation lentiviral vectors to avoid oncogenic effects of lentiviral vectors. To avoid decreasing of effectiveness of the episomal genetic treatment over time, we’ll integrate the G6PC gene into the genome using the CRISPR/dCas9-FokI, which has the least risk of off-target mutations. We plan to put the G6PC gene into the G6PC gene region or the safe harbor region AAVS1. We decided the intravenous(IV) route is more practical and effective for in-vivo gene therapy. However, since the intravenous route isn’t local, our vector may spread different tissues and G6PC synthesize in unwanted tissues and cause metabolic disorders. Therefore, we designed the envelope proteins of lentiviral vectors, and added miRNA target regions, so that our treatment will be specific to the liver. In addition, we used tetracycline dependent liver specific promoters to minimize the potential risks of continuous systems. By adhering to the ‘Primum Non Nocere’ principle, we made designs to increase the safety of our project at every stage, and planned to treat GSD Type1A ideally.