Molecular scalpel hope for muscular dystrophy
The gene for the protein dystrophin is damaged in people with Duchenne muscular dystrophy. Now, a drug trial on 19 children, published in `The Lancet` journal, used the new "scalpel" to remove damage and restore dystrophin production.
Duchenne muscular dystrophy affects one in every 3,500 newborn boys. Throughout life the muscle wastes away and children can need a wheelchair by the age of 10. The condition can become life-threatening before age of 30, when it affects the muscles needed to breathe and pump blood around the body.
The instructions for making a protein are in the genetic code, but this can be disrupted by mutations or deletions in the code. Stem cell and gene therapy research has tried to find ways of introducing functional dystrophin gene.
The study tried to do the best it could with the damaged code, say the scientists at the Institute of Child Health at University College London injected tailored pieces of antisense RNA — the scalpel.
This removed a piece of the genetic code allowing it to be matched up either side of the mutation. The result is a shorter, but still functional, dystrophin.
In the trial, seven out of the 19 children had some degree of dystrophin production restored — all of them were receiving the highest doses.
Lead scientist Prof Francesco Muntoni told the `BBC`: "The best result was 20% of normal dystrophin levels. That is quite remarkable considering the study was for 12 weeks.
"I`ve worked with patients with Duchenne muscular dystrophy for many years and this is the first time we can say with confidence that we`ve made a significant breakthrough towards finding a targeted treatment."
However, he said that as the scalpel was tailored to a specific mutation it could not benefit everyone, in this case around 13 per cent of patients. "The second most common mutation affects 11 per cent — which needs another scalpel."