Medical research: Mending muscles with CRISPR gene editing

The correction of muscle defects in a mouse model of Duchenne muscular dystrophy is demonstrated using novel applications of the CRISPR/Cas9 gene therapy system. The research, reported in Nature Communications this week, expands the gene therapy toolbox to target a wider range of genetic defects causing this disorder.

Duchenne muscular dystrophy is a disease that mainly affects newborn boys, and is caused by defects in a gene coding for a protein called dystrophin. Without dystrophin, skeletal muscles and the heart degenerate. Although gene editing tools such as the CRISPR/Cas9 system have shown some promise for the treatment of Duchenne muscular dystrophy, it has been difficult to create a therapy that can address the numerous genetic mutations that cause defects in dystrophin.

Jeffrey Chamberlain and colleagues expand the CRISPR/Cas9 repertoire to correct multiple defects in dystrophin, and test their approach in mice. The treatment restored dystrophin, both in the muscles and in the heart, to levels that resulted in improved muscle function. These results suggest that CRISPR/Cas9 may be suitable for the treatment of mutations found in a wide range of patients with Duchenne muscular dystrophy, and may similarly be applicable to other degenerative disorders affecting the heart and muscle.