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Scientists from UT Southwestern Medical Center have stopped the progression of Duchenne muscular dystrophy (DMD) in young mice with a novel gene-editing method. If it can be adapted for human use, it will be the first "genome editing treatment" for a disease that is said to be the most common and form of muscular dystrophy in young boys.

DMD breaks down muscle fibers and replaces them with fibrous or fatty tissue that weakens muscles gradually and boosts heart muscle disease.

"This is different from other therapeutic approaches, because it eliminates the cause of the disease," Eric Olson, senior author of the study, explained in a press release.

Scientists thus use a CRISPR gene-editing method in order to correct the DMD mutation, stimulating it in younger mice, with the help of the adeno-associated virus 9 (AAV9). This is used to boost the production of dystrophin protein. It would lead on to improved skeletal muscle structure and function over a period.

"AAV9 can efficiently infect humans in a tissue-specific manner, but it does not cause human disease or toxicity. It's a molecular missile for gene therapy," said Leonela Amoasii, co-lead author of the study with Chengzu Long.

"The CRISPR/Cas9 system is an adaptive immune system of single-celled organisms against the invading virus," added Long. "Ironically, this system was hijacked, we packaged it into a nonpathogenic virus, and corrected a genetic mutation in an animal model."

The gene-editing technique is being tried on human DMD patients, in order to test the efficacy further in larger preclinical animal models.

"The recent groundbreaking discoveries from the Olson laboratory using genome editing to correct the genetic mutation that causes DMD have accelerated the race to find a cure for this deadly disease," said Pradeep Mammen, Co-Director of the UTSW Wellstone Center, which helped fund the research. "The challenge now lies before Wellstone Center researchers to translate these discoveries in the mouse model of DMD into a therapy for patients with DMD."

The study was published in the Dec. 31 issue of Science.