Researchers have found what may be a permanent cure for Duchenne muscular dystrophy, a disabling and eventually fatal genetic condition that affects approximately one in 5,000 boys worldwide.
The disease, also called DMD, causes the body to make a defective copy of a skeletal protein called dystrophin that holds muscles together.
That defective protein causes muscles to weaken and wither to the point that boys with Duchennes end up wheelchair-bound, and usually die of heart or respiratory failure in their 20s and 30s.
It's an X chromosome-linked disorder, meaning the defective gene that makes dystrophin is passed on to sons by their mothers.
Girls have two copies of the X chromosome, instead of one, so they are spared the disabling condition even if they inherit the genetic mutation from their mother.
Cutting out the bad
Using the so-called CRISPR gene-editing technique, three independent groups of U.S. researchers literally cut out the defective portions of the dystrophin gene in mice, so the remaining unaffected DNA was able to make healthy copies of the essential muscle protein.
"We're able to cut in a very specific place, so it's directly cutting,” said Rhonda Bassel-Duby, a molecular biologist at the University of Texas Southwestern Medical Center who participated in the research, “and we're able to remove the mutant [DNA] and hook it up in a way that you will get functional dystrophin being made."
The treatment has to be performed only one time for it to permanently halt DMD progression.
Investigators described in the journal Science how they used a harmless virus to carry the editing machinery into the muscles.
However, much more research is needed before CRISPR becomes a reality for treating DMD, warned Bassel-Duby, though she remained optimistic.
"You know, I think this is really something that we can hopefully bring into clinics one day,” she said. “That is my dream."