Novel Gene-editing technique capable of stopping progression of DMD

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Researchers from UT Southwestern Medical Center have developed a new gene technology that has stopped the progression of Duchenne muscular dystrophy (DMD) in young mice. If the technique is advanced then the technique could lead to one of the successful genome-editing based treatments for the disease.

DMD takes place due to mutations in the X-linked DMD gene that encodes the protein dystrophin. The disease, which is the most common and severe form of muscular dystrophy among boys, affects one in 3,500 to 5,000 boys. As per the Centers for Disease Control and Prevention, the disease leads to premature death by the early 30s.

For past three decades, the genetic reason of the disease is known but no effective treatment is available for the same. DMD leads to break down of muscle fibers and replaces them with fatty tissues leading weak muscles. The condition can lead to heart muscle disease.

The researchers have used a gene-editing technique to permanently correct the DMD mutation that leads to the disease in young mice. Study’s senior author Dr. Eric Olson, Chairman of Molecular Biology, said that the technique is different from other approaches.

The technique called CRISPR/Cas9-mediated genome editing corrects the mutation in the germ line of mice and prevents muscular dystrophy. Though the technique is promising, it has also raised many challenges for clinical applications among humans. One of the main reasons is that germ line editing is not possible in humans. Therefore, strategies would have to be developed to deliver gene-editing parts to postnatal tissues.

In an experiment, the researchers have delivered the gene-editing components in mice through adeno-associated virus 9 (AAV9). The mice treated with the technique produced dystrophin protein and significant improvements came in the structure and function of skeletal muscle and heart.

Study’s co-researcher Dr. Leonela Amoasii from the Olson lab said, “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”. Dr. Olson said that the strategy can be used in many types of mutations within the human DMD patients.

The BBC notes that, researchers in the US have used gene editing to treat mice with Duchenne muscular dystrophy. A team at Duke University used a system known as CRISPR-Cas9 to delete DNA that was preventing cells from producing a protein essential for muscle function.

And a virus was used to deliver DNA alterations into the cells of mice.

In other news Sciencemag reported, the red-hot genome editing tool known as CRISPR has scored another achievement: Researchers have used it to treat a severe form of muscular dystrophy in mice. Three groups report today in Science that they wielded CRISPR to snip out part of a defective gene in mice with Duchenne muscular dystrophy (DMD), allowing the animals to make an essential muscle protein. The approach is the first time CRISPR has been successfully delivered throughout the body to treat grown animals with a genetic disease.

In a statement provided to UPI News, Scientists used the CRISPR/Cas9 method of gene editing to correct a mutation causing Duchenne muscular dystrophy, reversing the progressive disease in the experiments with mice, according to a new study.

DMD is the most common, and severe, form of muscular dystrophy among boys. The progressive disease is caused by a mutation in the x-linked DMD gene that encodes the protein dystrophin.