Genome editing therapeutics for the treatment of aortic aneurysm in Marfan Syndrome

About This Grant

PROJECT SUMMARY Gene editing offers the prospect of directly modifying any nucleotide(s) in the genome, including correction of pathogenic variants underlying disease. These technologies could form the basis of cures for currently untreatable genetic conditions. The work proposed in this application aims to identify genome editing strategies to prevent aortic pathology in Marfan syndrome (MFS). MFS is the most prevalent hereditary connective tissue disorder and is associated with significantly increased morbidity and mortality due to life-limiting thoracic aortic aneurysm and dissection. MFS is caused by heterozygous pathogenic variants in FBN1, the gene encoding the main structural component of extracellular microfibrils, fibrillin-1. Microfibrils are essential for providing structural elasticity and resilience, in addition to having a signaling role, and defects in both features are thought to contribute to elastic lamina fragmentation and aortic wall weakness. We hypothesize that gene editing correction of FBN1 pathogenic variants or genome editing-based upregulation of the structurally related protein FBN2 within aortic vascular smooth muscle will reduce risk of aortic root dilation and dissection, thereby limiting the major cause of morbidity and mortality in this disease. In the first aim, the candidate will identify a prime editing strategy to correct the Fbn1 C1041G pathogenic variant in aortic vascular smooth muscle of a murine model of MFS and will test this therapeutic strategy by monitoring aortic aneurysm. In the second aim, a machine learning model will be used to identify promoter variants, putative enhancers, and transcription factor binding site motifs within the FBN2 promoter region that are predicted to augment FBN2 expression. These elements will be functionally evaluated in a massively parallel reporter assay (MPRA). Finally, in vivo genome editing will be used to introduce an optimized FBN2 upregulatory strategy established through these analyses in the Fbn1C1041G/+ mouse model of MFS for correction of aortic pathology. In addition to establishing potential gene editing treatment strategies for aortic aneurysm in Marfan syndrome, these studies will enable the candidate to obtain expertise in the design and application of state-of-the-art gene editing tools that can be used to generate disease models and investigate therapies for many different genetic disorders, which he plans to pursue throughout his career as a physician-scientist.