AN RNA 鈥渂andage鈥� that masks genetic mutations has prompted boys with Duchenne muscular dystrophy (DMD) to make a missing, muscle-strengthening protein throughout their bodies for the first time.
Around 1 in 3500 boys are born with DMD, the result of mutations in a gene on the X chromosome for the protein dystrophin. Boys with DMD tend to need wheelchairs by age 12 and die of cardiac or respiratory failure before they reach 30.
鈥淲丑别苍 the dystrophin gene was identified 24 years ago, there were very high hopes that gene therapy would correct the condition,鈥� says of the University of Western Australia in Perth. But hopes fell when the gene鈥檚 complexity and size became clear 鈥� it is the largest known in humans. 鈥淩eintroducing a healthy gene was not as simple or straightforward as anticipated.鈥�
Advertisement
鈥淩eintroducing a healthy gene was not as simple or straightforward as anticipated鈥�
Rather than trying to correct the genetic defects, Wilton鈥檚 team created nucleic acid snippets that bind to sections of messenger RNA corresponding to the DMD mutations. If injected, these bandages cause the mutations, which normally prevent dystrophin production, to be skipped over during protein-making.
In 2003 the approach seemed to work in mice. In 2009, injecting the snippets into the foot muscle of seven boys with DMD triggered dystrophin production there. Now the team has injected the snippets into the blood of 20 boys with DMD.
Last week, Wilton told the in Melbourne, Australia, that tissue biopsies suggest dystrophin is being produced throughout the bodies of boys who received high doses of the bandage.
It is not yet clear if the dystrophin will increase the boys鈥� muscle strength, but Wilton points out it did in animals. The protein resembles the version found in men with the milder Becker鈥檚 MD, who live into their 60s.
鈥淭his is the most promising therapeutic option for Duchenne鈥檚,鈥� says of the University of Sydney.
