DMD is a fatal — and currently incurable — genetic condition that causes the body’s muscles to deteriorate over time.
The disease is always caused by errors in the gene for a muscle protein, called dystrophin. But for 10-15% of patients… the problem is caused by a duplication mutation, where part of the gene appears twice.
[Researcher Ronald] Cohn’s team injected [a model] mouse with a CRISPR molecule, designed to eliminate the mutation and (hopefully) restore the normal function of the gene.
The results were incredible.
Before and after pictures show a dramatic difference between the mouse’s muscle strength and condition. After the CRISPR treatment, signs of weakened muscles disappeared.
Not long ago, gene therapy became a promising treatment for Duchenne muscular dystrophy. But traditional gene therapy is a different process than gene editing. A gene therapy treatment works by injecting harmless, gene-carrying virus into the body to deliver a new, functional copy of a faulty gene. For DMD, that faulty gene is the dystrophin gene.
In the case of DMD caused by a duplication mutation, CRISPR can simply snip away the harmful duplicate gene, which is much simpler than delivering a new gene or replacing the old.