Duchenne Muscular Dystrophy (DMD) is a rare recessive X-linked disease affecting 1:5000 newborn boys and is caused by mutations in the dystrophin gene. The disease is characterised by progressive muscle wasting and the substitution of muscle tissue with fat/fibrotic and connective tissue. Individuals affected by DMD generally die in their mid-thirties due to cardiac failure.

Gene editing is a powerful technology that allows scientists to make precise changes to the DNA of living organisms. The most widely used gene editing tool is CRISPR/Cas9, which uses a protein called Cas9 to cut DNA at specific locations, allowing researchers to add, remove, or modify specific genes.

In this project, I am using a gene editing application based on CRISPR/Cas9 to permanently modify the dystrophin gene. In particular, the aim is to introduce a repair template carrying a short version of dystrophin, called microdystrophin, within the 5’ end of the dystrophin gene. This study needs the careful design of the RNA guides to drive Cas (the protein cutting the DNA) in a specific region of the DNA. RNA Guides were designed and screened in cellular models. Mouse/human homology regions were targeted so that any guide found to work well in humans can be tested later in the mouse model of DMD where the functional improvement can be assessed.